fiscal_core/xml_builder/

det.rs

//! Build `<det>` (item detail) elements of the NF-e XML.

use crate::FiscalError;
use crate::format_utils::{format_cents, format_decimal, format_rate4};
use crate::newtypes::{Cents, Rate, Rate4};
use crate::tax_ibs_cbs;
use crate::tax_icms::{self, IcmsCsosn, IcmsCst, IcmsTotals, IcmsVariant};
use crate::tax_is;
use crate::tax_issqn;
use crate::tax_pis_cofins_ipi::{self, CofinsData, IiData, IpiData, PisData};
use crate::types::{
    CombData, InvoiceBuildData, InvoiceItemData, InvoiceModel, SefazEnvironment, TaxRegime,
};
use crate::xml_utils::{TagContent, tag};

/// Constant used when emitting NFC-e in homologation environment (first item only).
const HOMOLOGATION_XPROD: &str =
    "NOTA FISCAL EMITIDA EM AMBIENTE DE HOMOLOGACAO - SEM VALOR FISCAL";

/// Result from building a single `<det>` element.
#[derive(Debug, Clone)]
pub struct DetResult {
    /// The serialised `<det>` XML string.
    pub xml: String,
    /// Accumulated ICMS totals contributed by this item.
    pub icms_totals: IcmsTotals,
    /// IPI value in cents contributed by this item.
    pub v_ipi: i64,
    /// PIS value in cents contributed by this item.
    pub v_pis: i64,
    /// COFINS value in cents contributed by this item.
    pub v_cofins: i64,
    /// II (import tax) value in cents contributed by this item.
    pub v_ii: i64,
    /// Freight value in cents for this item.
    pub v_frete: i64,
    /// Insurance value in cents for this item.
    pub v_seg: i64,
    /// Discount value in cents for this item.
    pub v_desc: i64,
    /// Other expenses value in cents for this item.
    pub v_outro: i64,
    /// Whether this item counts towards the invoice total (indTot).
    pub ind_tot: u8,
    /// Approximate total tax for this item (`vTotTrib`). Optional.
    pub v_tot_trib: i64,
    /// IPI devolution value in cents contributed by this item.
    pub v_ipi_devol: i64,
    /// PIS-ST value in cents contributed by this item (only when indSomaPISST = 1).
    pub v_pis_st: i64,
    /// COFINS-ST value in cents contributed by this item (only when indSomaCOFINSST = 1).
    pub v_cofins_st: i64,
    /// Whether this item has indDeduzDeson = 1 (desoneration deduction applies).
    pub ind_deduz_deson: bool,
    /// Whether this item uses ISSQN instead of ICMS.
    pub has_issqn: bool,
}

/// Map an invoice item's ICMS fields to the correct typed [`IcmsVariant`].
fn build_icms_variant(
    item: &InvoiceItemData,
    is_simples: bool,
) -> Result<IcmsVariant, FiscalError> {
    let orig = item.orig.clone().unwrap_or_else(|| "0".to_string());

    if is_simples {
        let csosn_code = if item.icms_cst.is_empty() {
            "102"
        } else {
            item.icms_cst.as_str()
        };

        let csosn = match csosn_code {
            "101" => IcmsCsosn::Csosn101 {
                orig,
                csosn: csosn_code.to_string(),
                p_cred_sn: item.icms_p_cred_sn.ok_or_else(|| {
                    FiscalError::MissingRequiredField {
                        field: "pCredSN".to_string(),
                    }
                })?,
                v_cred_icms_sn: item.icms_v_cred_icms_sn.ok_or_else(|| {
                    FiscalError::MissingRequiredField {
                        field: "vCredICMSSN".to_string(),
                    }
                })?,
            },
            "102" => IcmsCsosn::Csosn102 {
                orig,
                csosn: csosn_code.to_string(),
            },
            "103" => IcmsCsosn::Csosn103 {
                orig,
                csosn: csosn_code.to_string(),
            },
            "300" => IcmsCsosn::Csosn300 {
                orig,
                csosn: csosn_code.to_string(),
            },
            "400" => IcmsCsosn::Csosn400 {
                orig,
                csosn: csosn_code.to_string(),
            },
            "201" => IcmsCsosn::Csosn201 {
                orig,
                csosn: csosn_code.to_string(),
                mod_bc_st: item.icms_mod_bc_st.map(|v| v.to_string()).ok_or_else(|| {
                    FiscalError::MissingRequiredField {
                        field: "modBCST".to_string(),
                    }
                })?,
                p_mva_st: item.icms_p_mva_st,
                p_red_bc_st: item.icms_red_bc_st,
                v_bc_st: item
                    .icms_v_bc_st
                    .ok_or_else(|| FiscalError::MissingRequiredField {
                        field: "vBCST".to_string(),
                    })?,
                p_icms_st: item.icms_p_icms_st.ok_or_else(|| {
                    FiscalError::MissingRequiredField {
                        field: "pICMSST".to_string(),
                    }
                })?,
                v_icms_st: item.icms_v_icms_st.ok_or_else(|| {
                    FiscalError::MissingRequiredField {
                        field: "vICMSST".to_string(),
                    }
                })?,
                v_bc_fcp_st: item.icms_v_bc_fcp_st,
                p_fcp_st: item.icms_p_fcp_st,
                v_fcp_st: item.icms_v_fcp_st,
                p_cred_sn: item.icms_p_cred_sn,
                v_cred_icms_sn: item.icms_v_cred_icms_sn,
            },
            "202" => IcmsCsosn::Csosn202 {
                orig,
                csosn: csosn_code.to_string(),
                mod_bc_st: item.icms_mod_bc_st.map(|v| v.to_string()).ok_or_else(|| {
                    FiscalError::MissingRequiredField {
                        field: "modBCST".to_string(),
                    }
                })?,
                p_mva_st: item.icms_p_mva_st,
                p_red_bc_st: item.icms_red_bc_st,
                v_bc_st: item
                    .icms_v_bc_st
                    .ok_or_else(|| FiscalError::MissingRequiredField {
                        field: "vBCST".to_string(),
                    })?,
                p_icms_st: item.icms_p_icms_st.ok_or_else(|| {
                    FiscalError::MissingRequiredField {
                        field: "pICMSST".to_string(),
                    }
                })?,
                v_icms_st: item.icms_v_icms_st.ok_or_else(|| {
                    FiscalError::MissingRequiredField {
                        field: "vICMSST".to_string(),
                    }
                })?,
                v_bc_fcp_st: item.icms_v_bc_fcp_st,
                p_fcp_st: item.icms_p_fcp_st,
                v_fcp_st: item.icms_v_fcp_st,
            },
            "203" => IcmsCsosn::Csosn203 {
                orig,
                csosn: csosn_code.to_string(),
                mod_bc_st: item.icms_mod_bc_st.map(|v| v.to_string()).ok_or_else(|| {
                    FiscalError::MissingRequiredField {
                        field: "modBCST".to_string(),
                    }
                })?,
                p_mva_st: item.icms_p_mva_st,
                p_red_bc_st: item.icms_red_bc_st,
                v_bc_st: item
                    .icms_v_bc_st
                    .ok_or_else(|| FiscalError::MissingRequiredField {
                        field: "vBCST".to_string(),
                    })?,
                p_icms_st: item.icms_p_icms_st.ok_or_else(|| {
                    FiscalError::MissingRequiredField {
                        field: "pICMSST".to_string(),
                    }
                })?,
                v_icms_st: item.icms_v_icms_st.ok_or_else(|| {
                    FiscalError::MissingRequiredField {
                        field: "vICMSST".to_string(),
                    }
                })?,
                v_bc_fcp_st: item.icms_v_bc_fcp_st,
                p_fcp_st: item.icms_p_fcp_st,
                v_fcp_st: item.icms_v_fcp_st,
            },
            "500" => IcmsCsosn::Csosn500 {
                orig,
                csosn: csosn_code.to_string(),
                v_bc_st_ret: None,
                p_st: None,
                v_icms_substituto: item.icms_v_icms_substituto,
                v_icms_st_ret: None,
                v_bc_fcp_st_ret: None,
                p_fcp_st_ret: None,
                v_fcp_st_ret: None,
                p_red_bc_efet: None,
                v_bc_efet: None,
                p_icms_efet: None,
                v_icms_efet: None,
            },
            "900" => IcmsCsosn::Csosn900 {
                orig,
                csosn: csosn_code.to_string(),
                mod_bc: item.icms_mod_bc.map(|v| v.to_string()),
                v_bc: Some(item.total_price),
                p_red_bc: item.icms_red_bc,
                p_icms: Some(item.icms_rate),
                v_icms: Some(item.icms_amount),
                mod_bc_st: item.icms_mod_bc_st.map(|v| v.to_string()),
                p_mva_st: item.icms_p_mva_st,
                p_red_bc_st: item.icms_red_bc_st,
                v_bc_st: item.icms_v_bc_st,
                p_icms_st: item.icms_p_icms_st,
                v_icms_st: item.icms_v_icms_st,
                v_bc_fcp_st: item.icms_v_bc_fcp_st,
                p_fcp_st: item.icms_p_fcp_st,
                v_fcp_st: item.icms_v_fcp_st,
                p_cred_sn: item.icms_p_cred_sn,
                v_cred_icms_sn: item.icms_v_cred_icms_sn,
            },
            other => return Err(FiscalError::UnsupportedIcmsCsosn(other.to_string())),
        };
        Ok(csosn.into())
    } else {
        let cst_code = item.icms_cst.as_str();
        let cst = match cst_code {
            "00" => IcmsCst::Cst00 {
                orig,
                mod_bc: item
                    .icms_mod_bc
                    .map(|v| v.to_string())
                    .unwrap_or_else(|| "3".to_string()),
                v_bc: item.total_price,
                p_icms: item.icms_rate,
                v_icms: item.icms_amount,
                p_fcp: item.icms_p_fcp,
                v_fcp: item.icms_v_fcp,
            },
            "10" => IcmsCst::Cst10 {
                orig,
                mod_bc: item
                    .icms_mod_bc
                    .map(|v| v.to_string())
                    .unwrap_or_else(|| "3".to_string()),
                v_bc: item.total_price,
                p_icms: item.icms_rate,
                v_icms: item.icms_amount,
                v_bc_fcp: item.icms_v_bc_fcp,
                p_fcp: item.icms_p_fcp,
                v_fcp: item.icms_v_fcp,
                mod_bc_st: item.icms_mod_bc_st.map(|v| v.to_string()).ok_or_else(|| {
                    FiscalError::MissingRequiredField {
                        field: "modBCST".to_string(),
                    }
                })?,
                p_mva_st: item.icms_p_mva_st,
                p_red_bc_st: item.icms_red_bc_st,
                v_bc_st: item
                    .icms_v_bc_st
                    .ok_or_else(|| FiscalError::MissingRequiredField {
                        field: "vBCST".to_string(),
                    })?,
                p_icms_st: item.icms_p_icms_st.ok_or_else(|| {
                    FiscalError::MissingRequiredField {
                        field: "pICMSST".to_string(),
                    }
                })?,
                v_icms_st: item.icms_v_icms_st.ok_or_else(|| {
                    FiscalError::MissingRequiredField {
                        field: "vICMSST".to_string(),
                    }
                })?,
                v_bc_fcp_st: item.icms_v_bc_fcp_st,
                p_fcp_st: item.icms_p_fcp_st,
                v_fcp_st: item.icms_v_fcp_st,
                v_icms_st_deson: None,
                mot_des_icms_st: None,
            },
            "20" => IcmsCst::Cst20 {
                orig,
                mod_bc: item
                    .icms_mod_bc
                    .map(|v| v.to_string())
                    .unwrap_or_else(|| "3".to_string()),
                p_red_bc: item.icms_red_bc.unwrap_or(Rate(0)),
                v_bc: item.total_price,
                p_icms: item.icms_rate,
                v_icms: item.icms_amount,
                v_bc_fcp: item.icms_v_bc_fcp,
                p_fcp: item.icms_p_fcp,
                v_fcp: item.icms_v_fcp,
                v_icms_deson: item.icms_v_icms_deson,
                mot_des_icms: item.icms_mot_des_icms.map(|v| v.to_string()),
                ind_deduz_deson: item.icms_ind_deduz_deson.clone(),
            },
            "30" => IcmsCst::Cst30 {
                orig,
                mod_bc_st: item.icms_mod_bc_st.map(|v| v.to_string()).ok_or_else(|| {
                    FiscalError::MissingRequiredField {
                        field: "modBCST".to_string(),
                    }
                })?,
                p_mva_st: item.icms_p_mva_st,
                p_red_bc_st: item.icms_red_bc_st,
                v_bc_st: item
                    .icms_v_bc_st
                    .ok_or_else(|| FiscalError::MissingRequiredField {
                        field: "vBCST".to_string(),
                    })?,
                p_icms_st: item.icms_p_icms_st.ok_or_else(|| {
                    FiscalError::MissingRequiredField {
                        field: "pICMSST".to_string(),
                    }
                })?,
                v_icms_st: item.icms_v_icms_st.ok_or_else(|| {
                    FiscalError::MissingRequiredField {
                        field: "vICMSST".to_string(),
                    }
                })?,
                v_bc_fcp_st: item.icms_v_bc_fcp_st,
                p_fcp_st: item.icms_p_fcp_st,
                v_fcp_st: item.icms_v_fcp_st,
                v_icms_deson: item.icms_v_icms_deson,
                mot_des_icms: item.icms_mot_des_icms.map(|v| v.to_string()),
                ind_deduz_deson: item.icms_ind_deduz_deson.clone(),
            },
            "40" => IcmsCst::Cst40 {
                orig,
                v_icms_deson: item.icms_v_icms_deson,
                mot_des_icms: item.icms_mot_des_icms.map(|v| v.to_string()),
                ind_deduz_deson: item.icms_ind_deduz_deson.clone(),
            },
            "41" => IcmsCst::Cst41 {
                orig,
                v_icms_deson: item.icms_v_icms_deson,
                mot_des_icms: item.icms_mot_des_icms.map(|v| v.to_string()),
                ind_deduz_deson: item.icms_ind_deduz_deson.clone(),
            },
            "50" => IcmsCst::Cst50 {
                orig,
                v_icms_deson: item.icms_v_icms_deson,
                mot_des_icms: item.icms_mot_des_icms.map(|v| v.to_string()),
                ind_deduz_deson: item.icms_ind_deduz_deson.clone(),
            },
            "51" => IcmsCst::Cst51 {
                orig,
                mod_bc: item.icms_mod_bc.map(|v| v.to_string()),
                p_red_bc: item.icms_red_bc,
                c_benef_rbc: None,
                v_bc: Some(item.total_price),
                p_icms: Some(item.icms_rate),
                v_icms_op: None,
                p_dif: None,
                v_icms_dif: None,
                v_icms: Some(item.icms_amount),
                v_bc_fcp: item.icms_v_bc_fcp,
                p_fcp: item.icms_p_fcp,
                v_fcp: item.icms_v_fcp,
                p_fcp_dif: None,
                v_fcp_dif: None,
                v_fcp_efet: None,
            },
            "60" => IcmsCst::Cst60 {
                orig,
                v_bc_st_ret: None,
                p_st: None,
                v_icms_substituto: item.icms_v_icms_substituto,
                v_icms_st_ret: None,
                v_bc_fcp_st_ret: None,
                p_fcp_st_ret: None,
                v_fcp_st_ret: None,
                p_red_bc_efet: None,
                v_bc_efet: None,
                p_icms_efet: None,
                v_icms_efet: None,
            },
            "70" => IcmsCst::Cst70 {
                orig,
                mod_bc: item
                    .icms_mod_bc
                    .map(|v| v.to_string())
                    .unwrap_or_else(|| "3".to_string()),
                p_red_bc: item.icms_red_bc.unwrap_or(Rate(0)),
                v_bc: item.total_price,
                p_icms: item.icms_rate,
                v_icms: item.icms_amount,
                v_bc_fcp: item.icms_v_bc_fcp,
                p_fcp: item.icms_p_fcp,
                v_fcp: item.icms_v_fcp,
                mod_bc_st: item.icms_mod_bc_st.map(|v| v.to_string()).ok_or_else(|| {
                    FiscalError::MissingRequiredField {
                        field: "modBCST".to_string(),
                    }
                })?,
                p_mva_st: item.icms_p_mva_st,
                p_red_bc_st: item.icms_red_bc_st,
                v_bc_st: item
                    .icms_v_bc_st
                    .ok_or_else(|| FiscalError::MissingRequiredField {
                        field: "vBCST".to_string(),
                    })?,
                p_icms_st: item.icms_p_icms_st.ok_or_else(|| {
                    FiscalError::MissingRequiredField {
                        field: "pICMSST".to_string(),
                    }
                })?,
                v_icms_st: item.icms_v_icms_st.ok_or_else(|| {
                    FiscalError::MissingRequiredField {
                        field: "vICMSST".to_string(),
                    }
                })?,
                v_bc_fcp_st: item.icms_v_bc_fcp_st,
                p_fcp_st: item.icms_p_fcp_st,
                v_fcp_st: item.icms_v_fcp_st,
                v_icms_deson: item.icms_v_icms_deson,
                mot_des_icms: item.icms_mot_des_icms.map(|v| v.to_string()),
                ind_deduz_deson: item.icms_ind_deduz_deson.clone(),
                v_icms_st_deson: None,
                mot_des_icms_st: None,
            },
            "90" => IcmsCst::Cst90 {
                orig,
                mod_bc: item.icms_mod_bc.map(|v| v.to_string()),
                v_bc: Some(item.total_price),
                p_red_bc: item.icms_red_bc,
                c_benef_rbc: None,
                p_icms: Some(item.icms_rate),
                v_icms_op: None,
                p_dif: None,
                v_icms_dif: None,
                v_icms: Some(item.icms_amount),
                v_bc_fcp: item.icms_v_bc_fcp,
                p_fcp: item.icms_p_fcp,
                v_fcp: item.icms_v_fcp,
                p_fcp_dif: None,
                v_fcp_dif: None,
                v_fcp_efet: None,
                mod_bc_st: item.icms_mod_bc_st.map(|v| v.to_string()),
                p_mva_st: item.icms_p_mva_st,
                p_red_bc_st: item.icms_red_bc_st,
                v_bc_st: item.icms_v_bc_st,
                p_icms_st: item.icms_p_icms_st,
                v_icms_st: item.icms_v_icms_st,
                v_bc_fcp_st: item.icms_v_bc_fcp_st,
                p_fcp_st: item.icms_p_fcp_st,
                v_fcp_st: item.icms_v_fcp_st,
                v_icms_deson: item.icms_v_icms_deson,
                mot_des_icms: item.icms_mot_des_icms.map(|v| v.to_string()),
                ind_deduz_deson: item.icms_ind_deduz_deson.clone(),
                v_icms_st_deson: None,
                mot_des_icms_st: None,
            },
            other => return Err(FiscalError::UnsupportedIcmsCst(other.to_string())),
        };
        Ok(cst.into())
    }
}

/// Build a `<det nItem="N">` element for one invoice item.
pub(crate) fn build_det(
    item: &InvoiceItemData,
    data: &InvoiceBuildData,
) -> Result<DetResult, FiscalError> {
    // Validate NVE: up to 8 per item
    if item.nve.len() > 8 {
        return Err(FiscalError::InvalidTaxData(format!(
            "Item {}: NVE limited to 8 entries, got {}",
            item.item_number,
            item.nve.len()
        )));
    }

    let is_simples = matches!(
        data.issuer.tax_regime,
        TaxRegime::SimplesNacional | TaxRegime::SimplesExcess
    );

    let has_issqn = item.issqn.is_some();

    // Build ICMS (skipped when item has ISSQN)
    let mut icms_totals = IcmsTotals::default();
    let icms_xml = if has_issqn {
        String::new()
    } else {
        let icms_variant = build_icms_variant(item, is_simples)?;
        tax_icms::build_icms_xml(&icms_variant, &mut icms_totals)?
    };

    // Build ISSQN (optional — only when item.issqn is set)
    let issqn_xml = if let Some(ref issqn_data) = item.issqn {
        tax_issqn::build_issqn_xml(issqn_data)
    } else {
        String::new()
    };

    // Build PIS
    let pis_xml = tax_pis_cofins_ipi::build_pis_xml(&PisData {
        cst: item.pis_cst.clone(),
        v_bc: item.pis_v_bc.or(Some(Cents(0))),
        p_pis: item.pis_p_pis.or(Some(Rate4(0))),
        v_pis: item.pis_v_pis.or(Some(Cents(0))),
        q_bc_prod: item.pis_q_bc_prod,
        v_aliq_prod: item.pis_v_aliq_prod,
    });

    // Build COFINS
    let cofins_xml = tax_pis_cofins_ipi::build_cofins_xml(&CofinsData {
        cst: item.cofins_cst.clone(),
        v_bc: item.cofins_v_bc.or(Some(Cents(0))),
        p_cofins: item.cofins_p_cofins.or(Some(Rate4(0))),
        v_cofins: item.cofins_v_cofins.or(Some(Cents(0))),
        q_bc_prod: item.cofins_q_bc_prod,
        v_aliq_prod: item.cofins_v_aliq_prod,
    });

    // Build IPI (optional)
    let mut ipi_xml = String::new();
    let mut v_ipi = 0i64;
    if let Some(ref ipi_cst) = item.ipi_cst {
        ipi_xml = tax_pis_cofins_ipi::build_ipi_xml(&IpiData {
            cst: ipi_cst.clone(),
            c_enq: item.ipi_c_enq.clone().unwrap_or_else(|| "999".to_string()),
            v_bc: item.ipi_v_bc,
            p_ipi: item.ipi_p_ipi,
            v_ipi: item.ipi_v_ipi,
            q_unid: item.ipi_q_unid,
            v_unid: item.ipi_v_unid,
            ..IpiData::default()
        });
        v_ipi = item.ipi_v_ipi.map(|c| c.0).unwrap_or(0);
    }

    // Build II (optional)
    let mut ii_xml = String::new();
    let mut v_ii = 0i64;
    if let Some(ii_vbc) = item.ii_v_bc {
        ii_xml = tax_pis_cofins_ipi::build_ii_xml(&IiData {
            v_bc: ii_vbc,
            v_desp_adu: item.ii_v_desp_adu.unwrap_or(Cents(0)),
            v_ii: item.ii_v_ii.unwrap_or(Cents(0)),
            v_iof: item.ii_v_iof.unwrap_or(Cents(0)),
        });
        v_ii = item.ii_v_ii.map(|c| c.0).unwrap_or(0);
    }

    // Build prod options (rastro, veicProd, med, arma, comb, nRECOPI)
    let prod_options = build_prod_options(item);

    // Build PIS-ST (optional)
    let mut v_pis_st = 0i64;
    if let Some(ref pis_st_data) = item.pis_st {
        // Accumulate only when indSomaPISST == 1 (matches PHP)
        if pis_st_data.ind_soma_pis_st == Some(1) {
            v_pis_st = pis_st_data.v_pis.0;
        }
    }

    // Build COFINS-ST (optional)
    let mut v_cofins_st = 0i64;
    if let Some(ref cofins_st_data) = item.cofins_st {
        // Accumulate only when indSomaCOFINSST == 1 (matches PHP)
        if cofins_st_data.ind_soma_cofins_st == Some(1) {
            v_cofins_st = cofins_st_data.v_cofins.0;
        }
    }

    // Detect indDeduzDeson from item ICMS data
    let item_ind_deduz_deson = item
        .icms_ind_deduz_deson
        .as_deref()
        .map(|v| v == "1")
        .unwrap_or(false);

    // Build det-level extras (infAdProd, obsItem, DFeReferenciado)
    let det_extras = build_det_extras(item);

    // Assemble imposto
    let mut imposto_children: Vec<String> = Vec::new();
    if !icms_xml.is_empty() {
        imposto_children.push(icms_xml);
    }
    if !ipi_xml.is_empty() {
        imposto_children.push(ipi_xml);
    }
    // PIS or PISST (mutually exclusive per PHP sped-nfe)
    if let Some(ref pis_st) = item.pis_st {
        imposto_children.push(tax_pis_cofins_ipi::build_pis_st_xml(pis_st));
    } else {
        imposto_children.push(pis_xml);
    }
    // COFINS or COFINSST (mutually exclusive per PHP sped-nfe)
    if let Some(ref cofins_st) = item.cofins_st {
        imposto_children.push(tax_pis_cofins_ipi::build_cofins_st_xml(cofins_st));
    } else {
        imposto_children.push(cofins_xml);
    }
    if !ii_xml.is_empty() {
        imposto_children.push(ii_xml);
    }
    if !issqn_xml.is_empty() {
        imposto_children.push(issqn_xml);
    }

    // Build IS (Imposto Seletivo) -- optional, inside <imposto>
    // Only emitted when schema is PL_010 or later (matching PHP: $this->schema > 9)
    if data.schema_version.is_pl010() {
        if let Some(ref is_data) = item.is_data {
            imposto_children.push(tax_is::build_is_xml(is_data));
        }

        // Build IBS/CBS -- optional, inside <imposto>
        if let Some(ref ibs_cbs_data) = item.ibs_cbs {
            imposto_children.push(tax_ibs_cbs::build_ibs_cbs_xml(ibs_cbs_data));
        }
    }

    // Assemble prod
    let fc2 = |c: i64| format_cents(c, 2);
    let fc10 = |c: i64| format_cents(c, 10);
    let fd4 = |v: f64| format_decimal(v, 4);

    let mut prod_children = vec![
        tag("cProd", &[], TagContent::Text(&item.product_code)),
        tag(
            "cEAN",
            &[],
            TagContent::Text(item.c_ean.as_deref().unwrap_or("SEM GTIN")),
        ),
    ];
    if let Some(ref cb) = item.c_barra {
        prod_children.push(tag("cBarra", &[], TagContent::Text(cb)));
    }
    prod_children.push(tag(
        "xProd",
        &[],
        TagContent::Text(
            // PHP substitutes xProd for item 1 of NFC-e in homologation
            if item.item_number == 1
                && data.environment == SefazEnvironment::Homologation
                && data.model == InvoiceModel::Nfce
            {
                HOMOLOGATION_XPROD
            } else {
                &item.description
            },
        ),
    ));
    prod_children.push(tag("NCM", &[], TagContent::Text(&item.ncm)));
    for nve_code in &item.nve {
        prod_children.push(tag("NVE", &[], TagContent::Text(nve_code)));
    }
    if let Some(ref cest) = item.cest {
        prod_children.push(tag("CEST", &[], TagContent::Text(cest)));
        if let Some(ref ind) = item.cest_ind_escala {
            prod_children.push(tag("indEscala", &[], TagContent::Text(ind)));
        }
        if let Some(ref fab) = item.cest_cnpj_fab {
            prod_children.push(tag("CNPJFab", &[], TagContent::Text(fab)));
        }
    }
    if let Some(ref cb) = item.c_benef {
        prod_children.push(tag("cBenef", &[], TagContent::Text(cb)));
    }
    // gCred (crédito presumido ICMS) — up to 4 per item, inside <prod>
    for gc in item.g_cred.iter().take(4) {
        let p_str = format_rate4(gc.p_cred_presumido.0);
        let mut gc_children = vec![
            tag(
                "cCredPresumido",
                &[],
                TagContent::Text(&gc.c_cred_presumido),
            ),
            tag("pCredPresumido", &[], TagContent::Text(&p_str)),
        ];
        if let Some(v) = gc.v_cred_presumido {
            let v_str = format_cents(v.0, 2);
            gc_children.push(tag("vCredPresumido", &[], TagContent::Text(&v_str)));
        }
        prod_children.push(tag("gCred", &[], TagContent::Children(gc_children)));
    }
    if let Some(ref ex) = item.extipi {
        prod_children.push(tag("EXTIPI", &[], TagContent::Text(ex)));
    }
    prod_children.extend([
        tag("CFOP", &[], TagContent::Text(&item.cfop)),
        tag("uCom", &[], TagContent::Text(&item.unit_of_measure)),
        tag("qCom", &[], TagContent::Text(&fd4(item.quantity))),
        tag("vUnCom", &[], TagContent::Text(&fc10(item.unit_price.0))),
        tag("vProd", &[], TagContent::Text(&fc2(item.total_price.0))),
        tag(
            "cEANTrib",
            &[],
            TagContent::Text(item.c_ean_trib.as_deref().unwrap_or("SEM GTIN")),
        ),
    ]);
    if let Some(ref cbt) = item.c_barra_trib {
        prod_children.push(tag("cBarraTrib", &[], TagContent::Text(cbt)));
    }
    let u_trib = item
        .taxable_unit
        .as_deref()
        .unwrap_or(&item.unit_of_measure);
    let q_trib = item.taxable_quantity.unwrap_or(item.quantity);
    let v_un_trib = item
        .taxable_unit_price
        .map(|c| c.0)
        .unwrap_or(item.unit_price.0);
    prod_children.extend([
        tag("uTrib", &[], TagContent::Text(u_trib)),
        tag("qTrib", &[], TagContent::Text(&fd4(q_trib))),
        tag("vUnTrib", &[], TagContent::Text(&fc10(v_un_trib))),
    ]);
    if let Some(v) = item.v_frete {
        prod_children.push(tag("vFrete", &[], TagContent::Text(&fc2(v.0))));
    }
    if let Some(v) = item.v_seg {
        prod_children.push(tag("vSeg", &[], TagContent::Text(&fc2(v.0))));
    }
    if let Some(v) = item.v_desc {
        prod_children.push(tag("vDesc", &[], TagContent::Text(&fc2(v.0))));
    }
    if let Some(v) = item.v_outro {
        prod_children.push(tag("vOutro", &[], TagContent::Text(&fc2(v.0))));
    }
    let ind_tot_str = match item.ind_tot {
        Some(v) => v.to_string(),
        None => "1".to_string(),
    };
    prod_children.push(tag("indTot", &[], TagContent::Text(&ind_tot_str)));
    if item.ind_bem_movel_usado == Some(true) {
        prod_children.push(tag("indBemMovelUsado", &[], TagContent::Text("1")));
    }
    // DI (Declaração de Importação) — after indTot, before detExport
    if let Some(ref dis) = item.di {
        for di in dis.iter().take(100) {
            prod_children.push(build_di_xml(di));
        }
    }
    // detExport — after DI, before xPed
    if let Some(ref exports) = item.det_export {
        for dex in exports.iter().take(500) {
            prod_children.push(build_det_export_xml(dex));
        }
    }
    if let Some(ref xped) = item.x_ped {
        prod_children.push(tag("xPed", &[], TagContent::Text(xped)));
    }
    if let Some(ref nip) = item.n_item_ped {
        prod_children.push(tag("nItemPed", &[], TagContent::Text(nip)));
    }
    if let Some(ref nfci) = item.n_fci {
        prod_children.push(tag("nFCI", &[], TagContent::Text(nfci)));
    }
    prod_children.extend(prod_options);

    // impostoDevol (after imposto, before infAdProd)
    let mut v_ipi_devol = 0i64;
    let imposto_devol_xml = if let Some(ref devol) = item.imposto_devol {
        v_ipi_devol = devol.v_ipi_devol.0;
        let p_devol_str = format_decimal(devol.p_devol.0 as f64 / 100.0, 2);
        let v_ipi_devol_str = format_cents(devol.v_ipi_devol.0, 2);
        tag(
            "impostoDevol",
            &[],
            TagContent::Children(vec![
                tag("pDevol", &[], TagContent::Text(&p_devol_str)),
                tag(
                    "IPI",
                    &[],
                    TagContent::Children(vec![tag(
                        "vIPIDevol",
                        &[],
                        TagContent::Text(&v_ipi_devol_str),
                    )]),
                ),
            ]),
        )
    } else {
        String::new()
    };

    // Assemble det
    let nitem = item.item_number.to_string();
    let mut det_children = vec![
        tag("prod", &[], TagContent::Children(prod_children)),
        tag("imposto", &[], TagContent::Children(imposto_children)),
    ];
    if !imposto_devol_xml.is_empty() {
        det_children.push(imposto_devol_xml);
    }
    det_children.extend(det_extras);

    let xml = tag(
        "det",
        &[("nItem", &nitem)],
        TagContent::Children(det_children),
    );

    Ok(DetResult {
        xml,
        icms_totals,
        v_ipi,
        v_pis: item.pis_v_pis.map(|c| c.0).unwrap_or(0),
        v_cofins: item.cofins_v_cofins.map(|c| c.0).unwrap_or(0),
        v_ii,
        v_frete: item.v_frete.map(|c| c.0).unwrap_or(0),
        v_seg: item.v_seg.map(|c| c.0).unwrap_or(0),
        v_desc: item.v_desc.map(|c| c.0).unwrap_or(0),
        v_outro: item.v_outro.map(|c| c.0).unwrap_or(0),
        ind_tot: item.ind_tot.unwrap_or(1),
        v_tot_trib: item.v_tot_trib.map(|c| c.0).unwrap_or(0),
        v_ipi_devol,
        v_pis_st,
        v_cofins_st,
        ind_deduz_deson: item_ind_deduz_deson,
        has_issqn,
    })
}

fn build_prod_options(item: &InvoiceItemData) -> Vec<String> {
    let mut opts = Vec::new();

    // rastro (batch tracking)
    if let Some(ref rastros) = item.rastro {
        for r in rastros.iter().take(500) {
            let mut rastro_children = vec![
                tag("nLote", &[], TagContent::Text(&r.n_lote)),
                tag("qLote", &[], TagContent::Text(&format_decimal(r.q_lote, 3))),
                tag("dFab", &[], TagContent::Text(&r.d_fab)),
                tag("dVal", &[], TagContent::Text(&r.d_val)),
            ];
            if let Some(ref agreg) = r.c_agreg {
                rastro_children.push(tag("cAgreg", &[], TagContent::Text(agreg)));
            }
            opts.push(tag("rastro", &[], TagContent::Children(rastro_children)));
        }
    }

    // CHOICE group: veicProd, med, arma, nRECOPI (mutually exclusive)
    if let Some(ref v) = item.veic_prod {
        opts.push(tag(
            "veicProd",
            &[],
            TagContent::Children(vec![
                tag("tpOp", &[], TagContent::Text(&v.tp_op)),
                tag("chassi", &[], TagContent::Text(&v.chassi)),
                tag("cCor", &[], TagContent::Text(&v.c_cor)),
                tag("xCor", &[], TagContent::Text(&v.x_cor)),
                tag("pot", &[], TagContent::Text(&v.pot)),
                tag("cilin", &[], TagContent::Text(&v.cilin)),
                tag("pesoL", &[], TagContent::Text(&v.peso_l)),
                tag("pesoB", &[], TagContent::Text(&v.peso_b)),
                tag("nSerie", &[], TagContent::Text(&v.n_serie)),
                tag("tpComb", &[], TagContent::Text(&v.tp_comb)),
                tag("nMotor", &[], TagContent::Text(&v.n_motor)),
                tag("CMT", &[], TagContent::Text(&v.cmt)),
                tag("dist", &[], TagContent::Text(&v.dist)),
                tag("anoMod", &[], TagContent::Text(&v.ano_mod)),
                tag("anoFab", &[], TagContent::Text(&v.ano_fab)),
                tag("tpPint", &[], TagContent::Text(&v.tp_pint)),
                tag("tpVeic", &[], TagContent::Text(&v.tp_veic)),
                tag("espVeic", &[], TagContent::Text(&v.esp_veic)),
                tag("VIN", &[], TagContent::Text(&v.vin)),
                tag("condVeic", &[], TagContent::Text(&v.cond_veic)),
                tag("cMod", &[], TagContent::Text(&v.c_mod)),
                tag("cCorDENATRAN", &[], TagContent::Text(&v.c_cor_denatran)),
                tag("lota", &[], TagContent::Text(&v.lota)),
                tag("tpRest", &[], TagContent::Text(&v.tp_rest)),
            ]),
        ));
    } else if let Some(ref m) = item.med {
        let mut med_children = Vec::new();
        if let Some(ref code) = m.c_prod_anvisa {
            med_children.push(tag("cProdANVISA", &[], TagContent::Text(code)));
        }
        if let Some(ref reason) = m.x_motivo_isencao {
            med_children.push(tag("xMotivoIsencao", &[], TagContent::Text(reason)));
        }
        med_children.push(tag(
            "vPMC",
            &[],
            TagContent::Text(&format_cents(m.v_pmc.0, 2)),
        ));
        opts.push(tag("med", &[], TagContent::Children(med_children)));
    } else if let Some(ref arms) = item.arma {
        for a in arms.iter().take(500) {
            opts.push(tag(
                "arma",
                &[],
                TagContent::Children(vec![
                    tag("tpArma", &[], TagContent::Text(&a.tp_arma)),
                    tag("nSerie", &[], TagContent::Text(&a.n_serie)),
                    tag("nCano", &[], TagContent::Text(&a.n_cano)),
                    tag("descr", &[], TagContent::Text(&a.descr)),
                ]),
            ));
        }
    } else if let Some(ref recopi) = item.n_recopi {
        if !recopi.is_empty() {
            opts.push(tag("nRECOPI", &[], TagContent::Text(recopi)));
        }
    }

    // comb — fuel product data (after the CHOICE group, per NF-e schema order)
    if let Some(ref comb) = item.comb {
        opts.push(build_comb_xml(comb));
    }

    opts
}

/// Build a single `<DI>` element with its nested `<adi>` children.
fn build_di_xml(di: &crate::types::DiData) -> String {
    let mut children = vec![
        tag("nDI", &[], TagContent::Text(&di.n_di)),
        tag("dDI", &[], TagContent::Text(&di.d_di)),
        tag("xLocDesemb", &[], TagContent::Text(&di.x_loc_desemb)),
        tag("UFDesemb", &[], TagContent::Text(&di.uf_desemb)),
        tag("dDesemb", &[], TagContent::Text(&di.d_desemb)),
        tag("tpViaTransp", &[], TagContent::Text(&di.tp_via_transp)),
    ];
    if let Some(ref v) = di.v_afrmm {
        children.push(tag("vAFRMM", &[], TagContent::Text(&format_cents(v.0, 2))));
    }
    children.push(tag(
        "tpIntermedio",
        &[],
        TagContent::Text(&di.tp_intermedio),
    ));
    if let Some(ref cnpj) = di.cnpj {
        children.push(tag("CNPJ", &[], TagContent::Text(cnpj)));
    } else if let Some(ref cpf) = di.cpf {
        children.push(tag("CPF", &[], TagContent::Text(cpf)));
    }
    if let Some(ref uf) = di.uf_terceiro {
        children.push(tag("UFTerceiro", &[], TagContent::Text(uf)));
    }
    children.push(tag("cExportador", &[], TagContent::Text(&di.c_exportador)));
    // adi children (up to 999 per DI)
    for adi in di.adi.iter().take(999) {
        let mut adi_children = Vec::new();
        if let Some(ref n) = adi.n_adicao {
            adi_children.push(tag("nAdicao", &[], TagContent::Text(n)));
        }
        adi_children.push(tag("nSeqAdic", &[], TagContent::Text(&adi.n_seq_adic)));
        adi_children.push(tag("cFabricante", &[], TagContent::Text(&adi.c_fabricante)));
        if let Some(ref v) = adi.v_desc_di {
            adi_children.push(tag("vDescDI", &[], TagContent::Text(&format_cents(v.0, 2))));
        }
        if let Some(ref n) = adi.n_draw {
            adi_children.push(tag("nDraw", &[], TagContent::Text(n)));
        }
        children.push(tag("adi", &[], TagContent::Children(adi_children)));
    }
    tag("DI", &[], TagContent::Children(children))
}

/// Build a single `<detExport>` element with optional `<exportInd>`.
fn build_det_export_xml(dex: &crate::types::DetExportData) -> String {
    let mut children = Vec::new();
    if let Some(ref n) = dex.n_draw {
        children.push(tag("nDraw", &[], TagContent::Text(n)));
    }
    if dex.n_re.is_some() || dex.ch_nfe.is_some() || dex.q_export.is_some() {
        let mut exp_ind_children = Vec::new();
        if let Some(ref n) = dex.n_re {
            exp_ind_children.push(tag("nRE", &[], TagContent::Text(n)));
        }
        if let Some(ref ch) = dex.ch_nfe {
            exp_ind_children.push(tag("chNFe", &[], TagContent::Text(ch)));
        }
        if let Some(q) = dex.q_export {
            exp_ind_children.push(tag("qExport", &[], TagContent::Text(&format_decimal(q, 4))));
        }
        children.push(tag(
            "exportInd",
            &[],
            TagContent::Children(exp_ind_children),
        ));
    }
    tag("detExport", &[], TagContent::Children(children))
}

/// Build the `<comb>` element for fuel products.
///
/// Follows the PHP sped-nfe `tagcomb` / `tagencerrante` / `tagorigComb`
/// structure exactly: cProdANP, descANP, pGLP, pGNn, pGNi, vPart, CODIF,
/// qTemp, UFCons, CIDE, encerrante, pBio, origComb[].
fn build_comb_xml(comb: &CombData) -> String {
    let mut children = vec![
        tag("cProdANP", &[], TagContent::Text(&comb.c_prod_anp)),
        tag("descANP", &[], TagContent::Text(&comb.desc_anp)),
    ];

    if let Some(ref v) = comb.p_glp {
        children.push(tag("pGLP", &[], TagContent::Text(v)));
    }
    if let Some(ref v) = comb.p_gn_n {
        children.push(tag("pGNn", &[], TagContent::Text(v)));
    }
    if let Some(ref v) = comb.p_gn_i {
        children.push(tag("pGNi", &[], TagContent::Text(v)));
    }
    if let Some(ref v) = comb.v_part {
        children.push(tag("vPart", &[], TagContent::Text(v)));
    }
    if let Some(ref v) = comb.codif {
        children.push(tag("CODIF", &[], TagContent::Text(v)));
    }
    if let Some(ref v) = comb.q_temp {
        children.push(tag("qTemp", &[], TagContent::Text(v)));
    }

    children.push(tag("UFCons", &[], TagContent::Text(&comb.uf_cons)));

    // CIDE (conditional — only when qBCProd is present)
    if let Some(ref cide) = comb.cide {
        let cide_children = vec![
            tag("qBCProd", &[], TagContent::Text(&cide.q_bc_prod)),
            tag("vAliqProd", &[], TagContent::Text(&cide.v_aliq_prod)),
            tag("vCIDE", &[], TagContent::Text(&cide.v_cide)),
        ];
        children.push(tag("CIDE", &[], TagContent::Children(cide_children)));
    }

    // encerrante
    if let Some(ref enc) = comb.encerrante {
        let mut enc_children = vec![tag("nBico", &[], TagContent::Text(&enc.n_bico))];
        if let Some(ref bomba) = enc.n_bomba {
            enc_children.push(tag("nBomba", &[], TagContent::Text(bomba)));
        }
        enc_children.push(tag("nTanque", &[], TagContent::Text(&enc.n_tanque)));
        enc_children.push(tag("vEncIni", &[], TagContent::Text(&enc.v_enc_ini)));
        enc_children.push(tag("vEncFin", &[], TagContent::Text(&enc.v_enc_fin)));
        children.push(tag("encerrante", &[], TagContent::Children(enc_children)));
    }

    // pBio
    if let Some(ref v) = comb.p_bio {
        children.push(tag("pBio", &[], TagContent::Text(v)));
    }

    // origComb (may be multiple)
    if let Some(ref origins) = comb.orig_comb {
        for orig in origins {
            let orig_children = vec![
                tag("indImport", &[], TagContent::Text(&orig.ind_import)),
                tag("cUFOrig", &[], TagContent::Text(&orig.c_uf_orig)),
                tag("pOrig", &[], TagContent::Text(&orig.p_orig)),
            ];
            children.push(tag("origComb", &[], TagContent::Children(orig_children)));
        }
    }

    tag("comb", &[], TagContent::Children(children))
}

fn build_det_extras(item: &InvoiceItemData) -> Vec<String> {
    let mut extras = Vec::new();

    if let Some(ref info) = item.inf_ad_prod {
        extras.push(tag("infAdProd", &[], TagContent::Text(info)));
    }

    if let Some(ref obs) = item.obs_item {
        let mut obs_children = Vec::new();
        if let Some(ref cont) = obs.obs_cont {
            obs_children.push(tag(
                "obsCont",
                &[("xCampo", &cont.x_campo)],
                TagContent::Children(vec![tag("xTexto", &[], TagContent::Text(&cont.x_texto))]),
            ));
        }
        if let Some(ref fisco) = obs.obs_fisco {
            obs_children.push(tag(
                "obsFisco",
                &[("xCampo", &fisco.x_campo)],
                TagContent::Children(vec![tag("xTexto", &[], TagContent::Text(&fisco.x_texto))]),
            ));
        }
        extras.push(tag("obsItem", &[], TagContent::Children(obs_children)));
    }

    if let Some(ref dfe) = item.dfe_referenciado {
        let mut dfe_children = vec![tag("chaveAcesso", &[], TagContent::Text(&dfe.chave_acesso))];
        if let Some(ref n) = dfe.n_item {
            dfe_children.push(tag("nItem", &[], TagContent::Text(n)));
        }
        extras.push(tag(
            "DFeReferenciado",
            &[],
            TagContent::Children(dfe_children),
        ));
    }

    extras
}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::newtypes::{Cents, IbgeCode, Rate, Rate4};
    use crate::tax_issqn::IssqnData as TaxIssqnData;
    use crate::types::{
        ArmaData, CideData, CombData, EncerranteData, GCredData, InvoiceItemData, InvoiceModel,
        IssuerData, MedData, OrigCombData, RastroData, SefazEnvironment, TaxRegime, VeicProdData,
    };

    fn sample_build_data() -> InvoiceBuildData {
        let issuer = IssuerData::new(
            "12345678000199",
            "123456789",
            "Test Company",
            TaxRegime::SimplesNacional,
            "SP",
            IbgeCode("3550308".to_string()),
            "Sao Paulo",
            "Av Paulista",
            "1000",
            "Bela Vista",
            "01310100",
        );

        InvoiceBuildData {
            schema_version: crate::types::SchemaVersion::PL009,
            model: InvoiceModel::Nfe,
            series: 1,
            number: 1,
            emission_type: crate::types::EmissionType::Normal,
            environment: SefazEnvironment::Homologation,
            issued_at: chrono::Utc::now()
                .with_timezone(&chrono::FixedOffset::west_opt(3 * 3600).expect("valid offset")),
            operation_nature: "VENDA".to_string(),
            issuer,
            recipient: None,
            items: Vec::new(),
            payments: Vec::new(),
            change_amount: None,
            payment_card_details: None,
            contingency: None,
            exit_at: None,
            operation_type: None,
            purpose_code: None,
            intermediary_indicator: None,
            emission_process: None,
            consumer_type: None,
            buyer_presence: None,
            print_format: None,
            references: None,
            transport: None,
            billing: None,
            withdrawal: None,
            delivery: None,
            authorized_xml: None,
            additional_info: None,
            intermediary: None,
            ret_trib: None,
            tech_responsible: None,
            purchase: None,
            export: None,
            issqn_tot: None,
            cana: None,
            agropecuario: None,
            compra_gov: None,
            pag_antecipado: None,
            is_tot: None,
            ibs_cbs_tot: None,
            destination_indicator: None,
            ver_proc: None,
            only_ascii: false,
            calculation_method: crate::types::CalculationMethod::V2,
        }
    }

    fn sample_item() -> InvoiceItemData {
        InvoiceItemData::new(
            1,
            "001",
            "Gasolina Comum",
            "27101259",
            "5102",
            "LT",
            50.0,
            Cents(599),
            Cents(29950),
            "102",
            Rate(0),
            Cents(0),
            "99",
            "99",
        )
    }

    // ── Combustíveis ────────────────────────────────────────────────────────

    #[test]
    fn comb_minimal_produces_correct_xml() {
        let comb = CombData::new("210203001", "GLP", "SP");
        let xml = build_comb_xml(&comb);

        assert_eq!(
            xml,
            "<comb>\
                <cProdANP>210203001</cProdANP>\
                <descANP>GLP</descANP>\
                <UFCons>SP</UFCons>\
            </comb>"
        );
    }

    #[test]
    fn comb_with_glp_percentages() {
        let comb = CombData::new("210203001", "GLP", "SP")
            .p_glp("60.0000")
            .p_gn_n("25.0000")
            .p_gn_i("15.0000")
            .v_part("3.50");

        let xml = build_comb_xml(&comb);

        assert_eq!(
            xml,
            "<comb>\
                <cProdANP>210203001</cProdANP>\
                <descANP>GLP</descANP>\
                <pGLP>60.0000</pGLP>\
                <pGNn>25.0000</pGNn>\
                <pGNi>15.0000</pGNi>\
                <vPart>3.50</vPart>\
                <UFCons>SP</UFCons>\
            </comb>"
        );
    }

    #[test]
    fn comb_with_codif_and_qtemp() {
        let comb = CombData::new("320102001", "GASOLINA COMUM", "PR")
            .codif("123456789")
            .q_temp("1000.0000");

        let xml = build_comb_xml(&comb);

        assert_eq!(
            xml,
            "<comb>\
                <cProdANP>320102001</cProdANP>\
                <descANP>GASOLINA COMUM</descANP>\
                <CODIF>123456789</CODIF>\
                <qTemp>1000.0000</qTemp>\
                <UFCons>PR</UFCons>\
            </comb>"
        );
    }

    #[test]
    fn comb_with_cide() {
        let cide = CideData::new("1000.0000", "0.0700", "70.00");
        let comb = CombData::new("320102001", "GASOLINA COMUM", "SP").cide(cide);

        let xml = build_comb_xml(&comb);

        assert_eq!(
            xml,
            "<comb>\
                <cProdANP>320102001</cProdANP>\
                <descANP>GASOLINA COMUM</descANP>\
                <UFCons>SP</UFCons>\
                <CIDE>\
                    <qBCProd>1000.0000</qBCProd>\
                    <vAliqProd>0.0700</vAliqProd>\
                    <vCIDE>70.00</vCIDE>\
                </CIDE>\
            </comb>"
        );
    }

    #[test]
    fn comb_with_encerrante() {
        let enc = EncerranteData::new("1", "1", "1234.567", "1284.567").n_bomba("2");
        let comb = CombData::new("320102001", "GASOLINA COMUM", "SP").encerrante(enc);

        let xml = build_comb_xml(&comb);

        assert_eq!(
            xml,
            "<comb>\
                <cProdANP>320102001</cProdANP>\
                <descANP>GASOLINA COMUM</descANP>\
                <UFCons>SP</UFCons>\
                <encerrante>\
                    <nBico>1</nBico>\
                    <nBomba>2</nBomba>\
                    <nTanque>1</nTanque>\
                    <vEncIni>1234.567</vEncIni>\
                    <vEncFin>1284.567</vEncFin>\
                </encerrante>\
            </comb>"
        );
    }

    #[test]
    fn comb_encerrante_without_bomba() {
        let enc = EncerranteData::new("3", "2", "5000.000", "5050.000");
        let comb = CombData::new("320102001", "GASOLINA COMUM", "RJ").encerrante(enc);

        let xml = build_comb_xml(&comb);

        assert_eq!(
            xml,
            "<comb>\
                <cProdANP>320102001</cProdANP>\
                <descANP>GASOLINA COMUM</descANP>\
                <UFCons>RJ</UFCons>\
                <encerrante>\
                    <nBico>3</nBico>\
                    <nTanque>2</nTanque>\
                    <vEncIni>5000.000</vEncIni>\
                    <vEncFin>5050.000</vEncFin>\
                </encerrante>\
            </comb>"
        );
    }

    #[test]
    fn comb_with_pbio() {
        let comb = CombData::new("810102001", "OLEO DIESEL B S10", "SP").p_bio("15.0000");

        let xml = build_comb_xml(&comb);

        assert_eq!(
            xml,
            "<comb>\
                <cProdANP>810102001</cProdANP>\
                <descANP>OLEO DIESEL B S10</descANP>\
                <UFCons>SP</UFCons>\
                <pBio>15.0000</pBio>\
            </comb>"
        );
    }

    #[test]
    fn comb_with_orig_comb_single() {
        let orig = OrigCombData::new("0", "35", "100.0000");
        let comb = CombData::new("320102001", "GASOLINA COMUM", "SP").orig_comb(vec![orig]);

        let xml = build_comb_xml(&comb);

        assert_eq!(
            xml,
            "<comb>\
                <cProdANP>320102001</cProdANP>\
                <descANP>GASOLINA COMUM</descANP>\
                <UFCons>SP</UFCons>\
                <origComb>\
                    <indImport>0</indImport>\
                    <cUFOrig>35</cUFOrig>\
                    <pOrig>100.0000</pOrig>\
                </origComb>\
            </comb>"
        );
    }

    #[test]
    fn comb_with_orig_comb_multiple() {
        let orig1 = OrigCombData::new("0", "35", "70.0000");
        let orig2 = OrigCombData::new("1", "99", "30.0000");
        let comb = CombData::new("320102001", "GASOLINA COMUM", "SP").orig_comb(vec![orig1, orig2]);

        let xml = build_comb_xml(&comb);

        assert_eq!(
            xml,
            "<comb>\
                <cProdANP>320102001</cProdANP>\
                <descANP>GASOLINA COMUM</descANP>\
                <UFCons>SP</UFCons>\
                <origComb>\
                    <indImport>0</indImport>\
                    <cUFOrig>35</cUFOrig>\
                    <pOrig>70.0000</pOrig>\
                </origComb>\
                <origComb>\
                    <indImport>1</indImport>\
                    <cUFOrig>99</cUFOrig>\
                    <pOrig>30.0000</pOrig>\
                </origComb>\
            </comb>"
        );
    }

    #[test]
    fn comb_full_with_all_fields() {
        let cide = CideData::new("500.0000", "0.0700", "35.00");
        let enc = EncerranteData::new("1", "1", "10000.000", "10050.000").n_bomba("1");
        let orig = OrigCombData::new("0", "35", "100.0000");

        let comb = CombData::new("210203001", "GLP", "SP")
            .p_glp("60.0000")
            .p_gn_n("25.0000")
            .p_gn_i("15.0000")
            .v_part("3.50")
            .codif("999888777")
            .q_temp("500.0000")
            .cide(cide)
            .encerrante(enc)
            .p_bio("12.0000")
            .orig_comb(vec![orig]);

        let xml = build_comb_xml(&comb);

        assert_eq!(
            xml,
            "<comb>\
                <cProdANP>210203001</cProdANP>\
                <descANP>GLP</descANP>\
                <pGLP>60.0000</pGLP>\
                <pGNn>25.0000</pGNn>\
                <pGNi>15.0000</pGNi>\
                <vPart>3.50</vPart>\
                <CODIF>999888777</CODIF>\
                <qTemp>500.0000</qTemp>\
                <UFCons>SP</UFCons>\
                <CIDE>\
                    <qBCProd>500.0000</qBCProd>\
                    <vAliqProd>0.0700</vAliqProd>\
                    <vCIDE>35.00</vCIDE>\
                </CIDE>\
                <encerrante>\
                    <nBico>1</nBico>\
                    <nBomba>1</nBomba>\
                    <nTanque>1</nTanque>\
                    <vEncIni>10000.000</vEncIni>\
                    <vEncFin>10050.000</vEncFin>\
                </encerrante>\
                <pBio>12.0000</pBio>\
                <origComb>\
                    <indImport>0</indImport>\
                    <cUFOrig>35</cUFOrig>\
                    <pOrig>100.0000</pOrig>\
                </origComb>\
            </comb>"
        );
    }

    #[test]
    fn comb_in_det_xml() {
        let comb = CombData::new("320102001", "GASOLINA COMUM", "SP");
        let item = sample_item().comb(comb);
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        // <comb> appears inside <prod>
        let prod_start = result.xml.find("<prod>").expect("<prod> must exist");
        let prod_end = result.xml.find("</prod>").expect("</prod> must exist");
        let prod_section = &result.xml[prod_start..prod_end];

        assert!(prod_section.contains("<comb>"));
        assert!(prod_section.contains("<cProdANP>320102001</cProdANP>"));
        assert!(prod_section.contains("<descANP>GASOLINA COMUM</descANP>"));
        assert!(prod_section.contains("<UFCons>SP</UFCons>"));
        assert!(prod_section.contains("</comb>"));
    }

    // ── ISSQN ───────────────────────────────────────────────────────────────

    #[test]
    fn issqn_item_produces_issqn_tag_not_icms() {
        let issqn_data = TaxIssqnData::new(10000, 500, 500, "3550308", "14.01")
            .ind_iss("1")
            .ind_incentivo("2");
        let item = sample_item().issqn(issqn_data);
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        // ISSQN tag present inside <imposto>
        assert!(result.xml.contains("<ISSQN>"));
        assert!(result.xml.contains("<vBC>100.00</vBC>"));
        assert!(result.xml.contains("<vAliq>5.0000</vAliq>"));
        assert!(result.xml.contains("<vISSQN>5.00</vISSQN>"));
        assert!(result.xml.contains("<cMunFG>3550308</cMunFG>"));
        assert!(result.xml.contains("<cListServ>14.01</cListServ>"));
        assert!(result.xml.contains("<indISS>1</indISS>"));
        assert!(result.xml.contains("<indIncentivo>2</indIncentivo>"));
        assert!(result.xml.contains("</ISSQN>"));

        // ICMS should NOT be present for ISSQN items
        assert!(!result.xml.contains("<ICMS>"));
        assert!(!result.xml.contains("</ICMS>"));
        assert!(result.has_issqn);
    }

    #[test]
    fn issqn_item_with_all_optional_fields() {
        let issqn_data = TaxIssqnData::new(20000, 300, 600, "3304557", "07.02")
            .v_deducao(1000)
            .v_outro(500)
            .v_desc_incond(200)
            .v_desc_cond(100)
            .v_iss_ret(300)
            .ind_iss("1")
            .c_servico("1234")
            .c_mun("3304557")
            .c_pais("1058")
            .n_processo("ABC123")
            .ind_incentivo("1");

        let item = sample_item().issqn(issqn_data);
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<vBC>200.00</vBC>"));
        assert!(result.xml.contains("<vAliq>3.0000</vAliq>"));
        assert!(result.xml.contains("<vISSQN>6.00</vISSQN>"));
        assert!(result.xml.contains("<vDeducao>10.00</vDeducao>"));
        assert!(result.xml.contains("<vOutro>5.00</vOutro>"));
        assert!(result.xml.contains("<vDescIncond>2.00</vDescIncond>"));
        assert!(result.xml.contains("<vDescCond>1.00</vDescCond>"));
        assert!(result.xml.contains("<vISSRet>3.00</vISSRet>"));
        assert!(result.xml.contains("<cServico>1234</cServico>"));
        assert!(result.xml.contains("<cMun>3304557</cMun>"));
        assert!(result.xml.contains("<cPais>1058</cPais>"));
        assert!(result.xml.contains("<nProcesso>ABC123</nProcesso>"));
        assert!(result.xml.contains("<indIncentivo>1</indIncentivo>"));
        assert!(result.has_issqn);
    }

    #[test]
    fn non_issqn_item_has_icms_and_no_issqn() {
        let item = sample_item();
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<ICMS"));
        assert!(!result.xml.contains("<ISSQN>"));
        assert!(!result.has_issqn);
    }

    // ── Declaração de Importação (DI) ──────────────────────────────────────

    #[test]
    fn di_minimal_with_one_adi() {
        use crate::types::{AdiData, DiData};

        let adi = AdiData::new("1", "FABRICANTE_X").n_adicao("001");
        let di = DiData::new(
            "1234567890",
            "2025-01-15",
            "Santos",
            "SP",
            "2025-01-20",
            "1",
            "1",
            "EXP001",
            vec![adi],
        );
        let xml = build_di_xml(&di);

        assert_eq!(
            xml,
            "<DI>\
                <nDI>1234567890</nDI>\
                <dDI>2025-01-15</dDI>\
                <xLocDesemb>Santos</xLocDesemb>\
                <UFDesemb>SP</UFDesemb>\
                <dDesemb>2025-01-20</dDesemb>\
                <tpViaTransp>1</tpViaTransp>\
                <tpIntermedio>1</tpIntermedio>\
                <cExportador>EXP001</cExportador>\
                <adi>\
                    <nAdicao>001</nAdicao>\
                    <nSeqAdic>1</nSeqAdic>\
                    <cFabricante>FABRICANTE_X</cFabricante>\
                </adi>\
            </DI>"
        );
    }

    #[test]
    fn di_with_all_optional_fields() {
        use crate::types::{AdiData, DiData};

        let adi = AdiData::new("1", "FAB_Y")
            .n_adicao("002")
            .v_desc_di(Cents(15000))
            .n_draw("20259999999");
        let di = DiData::new(
            "DI-2025-001",
            "2025-03-01",
            "Paranagua",
            "PR",
            "2025-03-05",
            "1",
            "2",
            "EXP002",
            vec![adi],
        )
        .v_afrmm(Cents(5000))
        .cnpj("12345678000199")
        .uf_terceiro("RJ");

        let xml = build_di_xml(&di);

        assert_eq!(
            xml,
            "<DI>\
                <nDI>DI-2025-001</nDI>\
                <dDI>2025-03-01</dDI>\
                <xLocDesemb>Paranagua</xLocDesemb>\
                <UFDesemb>PR</UFDesemb>\
                <dDesemb>2025-03-05</dDesemb>\
                <tpViaTransp>1</tpViaTransp>\
                <vAFRMM>50.00</vAFRMM>\
                <tpIntermedio>2</tpIntermedio>\
                <CNPJ>12345678000199</CNPJ>\
                <UFTerceiro>RJ</UFTerceiro>\
                <cExportador>EXP002</cExportador>\
                <adi>\
                    <nAdicao>002</nAdicao>\
                    <nSeqAdic>1</nSeqAdic>\
                    <cFabricante>FAB_Y</cFabricante>\
                    <vDescDI>150.00</vDescDI>\
                    <nDraw>20259999999</nDraw>\
                </adi>\
            </DI>"
        );
    }

    #[test]
    fn di_with_cpf_instead_of_cnpj() {
        use crate::types::{AdiData, DiData};

        let adi = AdiData::new("1", "FAB_Z");
        let di = DiData::new(
            "DI-CPF",
            "2025-06-01",
            "Recife",
            "PE",
            "2025-06-03",
            "7",
            "3",
            "EXP003",
            vec![adi],
        )
        .cpf("12345678901");

        let xml = build_di_xml(&di);
        assert!(xml.contains("<CPF>12345678901</CPF>"));
        assert!(!xml.contains("<CNPJ>"));
    }

    #[test]
    fn di_with_multiple_adi() {
        use crate::types::{AdiData, DiData};

        let adi1 = AdiData::new("1", "FAB_A").n_adicao("001");
        let adi2 = AdiData::new("2", "FAB_B").n_adicao("001");
        let di = DiData::new(
            "DI-MULTI",
            "2025-01-01",
            "Santos",
            "SP",
            "2025-01-05",
            "1",
            "1",
            "EXP-M",
            vec![adi1, adi2],
        );
        let xml = build_di_xml(&di);

        // Both adi elements present
        let count = xml.matches("<adi>").count();
        assert_eq!(count, 2, "expected 2 <adi> elements, got {count}");
        assert!(xml.contains("<nSeqAdic>1</nSeqAdic>"));
        assert!(xml.contains("<nSeqAdic>2</nSeqAdic>"));
        assert!(xml.contains("<cFabricante>FAB_A</cFabricante>"));
        assert!(xml.contains("<cFabricante>FAB_B</cFabricante>"));
    }

    #[test]
    fn di_in_det_xml_between_ind_tot_and_xped() {
        use crate::types::{AdiData, DiData};

        let adi = AdiData::new("1", "FAB").n_adicao("001");
        let di = DiData::new(
            "DI-001",
            "2025-01-15",
            "Santos",
            "SP",
            "2025-01-20",
            "1",
            "1",
            "EXP",
            vec![adi],
        );
        let item = sample_item().di(vec![di]).x_ped("PO-123");
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        let xml = &result.xml;
        let ind_tot_pos = xml.find("</indTot>").expect("</indTot> must exist");
        let di_pos = xml.find("<DI>").expect("<DI> must exist");
        let xped_pos = xml.find("<xPed>").expect("<xPed> must exist");

        assert!(di_pos > ind_tot_pos, "DI must come after indTot");
        assert!(xped_pos > di_pos, "xPed must come after DI");
    }

    // ── Detalhe de Exportação (detExport) ──────────────────────────────────

    #[test]
    fn det_export_with_n_draw_only() {
        use crate::types::DetExportData;

        let dex = DetExportData::new().n_draw("20250000001");
        let xml = build_det_export_xml(&dex);

        assert_eq!(
            xml,
            "<detExport>\
                <nDraw>20250000001</nDraw>\
            </detExport>"
        );
    }

    #[test]
    fn det_export_with_export_ind() {
        use crate::types::DetExportData;

        let dex = DetExportData::new()
            .n_draw("20250000002")
            .n_re("123456789012")
            .ch_nfe("12345678901234567890123456789012345678901234")
            .q_export(100.5);
        let xml = build_det_export_xml(&dex);

        assert_eq!(
            xml,
            "<detExport>\
                <nDraw>20250000002</nDraw>\
                <exportInd>\
                    <nRE>123456789012</nRE>\
                    <chNFe>12345678901234567890123456789012345678901234</chNFe>\
                    <qExport>100.5000</qExport>\
                </exportInd>\
            </detExport>"
        );
    }

    #[test]
    fn det_export_empty() {
        use crate::types::DetExportData;

        let dex = DetExportData::new();
        let xml = build_det_export_xml(&dex);

        assert_eq!(xml, "<detExport></detExport>");
    }

    #[test]
    fn det_export_in_det_xml_between_ind_tot_and_xped() {
        use crate::types::DetExportData;

        let dex = DetExportData::new().n_draw("20250000001");
        let item = sample_item().det_export(vec![dex]).x_ped("PO-456");
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        let xml = &result.xml;
        let ind_tot_pos = xml.find("</indTot>").expect("</indTot> must exist");
        let det_exp_pos = xml.find("<detExport>").expect("<detExport> must exist");
        let xped_pos = xml.find("<xPed>").expect("<xPed> must exist");

        assert!(
            det_exp_pos > ind_tot_pos,
            "detExport must come after indTot"
        );
        assert!(xped_pos > det_exp_pos, "xPed must come after detExport");
    }

    // ── Imposto Devolvido (impostoDevol) ───────────────────────────────────

    #[test]
    fn imposto_devol_produces_correct_xml() {
        use crate::types::ImpostoDevolData;

        let devol = ImpostoDevolData::new(Rate(10000), Cents(5000));
        let item = sample_item().imposto_devol(devol);
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains(
            "<impostoDevol>\
                <pDevol>100.00</pDevol>\
                <IPI>\
                    <vIPIDevol>50.00</vIPIDevol>\
                </IPI>\
            </impostoDevol>"
        ));
        assert_eq!(result.v_ipi_devol, 5000);
    }

    #[test]
    fn imposto_devol_50_percent() {
        use crate::types::ImpostoDevolData;

        let devol = ImpostoDevolData::new(Rate(5000), Cents(2500));
        let item = sample_item().imposto_devol(devol);
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<pDevol>50.00</pDevol>"));
        assert!(result.xml.contains("<vIPIDevol>25.00</vIPIDevol>"));
        assert_eq!(result.v_ipi_devol, 2500);
    }

    #[test]
    fn imposto_devol_after_imposto_before_inf_ad_prod() {
        use crate::types::ImpostoDevolData;

        let devol = ImpostoDevolData::new(Rate(10000), Cents(1000));
        let item = sample_item().imposto_devol(devol).inf_ad_prod("test info");
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        let imposto_end = result
            .xml
            .find("</imposto>")
            .expect("</imposto> must exist");
        let devol_pos = result
            .xml
            .find("<impostoDevol>")
            .expect("<impostoDevol> must exist");
        let inf_ad_pos = result
            .xml
            .find("<infAdProd>")
            .expect("<infAdProd> must exist");

        assert!(
            devol_pos > imposto_end,
            "impostoDevol must come after </imposto>"
        );
        assert!(
            inf_ad_pos > devol_pos,
            "infAdProd must come after impostoDevol"
        );
    }

    #[test]
    fn no_imposto_devol_when_none() {
        let item = sample_item();
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(!result.xml.contains("<impostoDevol>"));
        assert_eq!(result.v_ipi_devol, 0);
    }

    // ── NVE (Nomenclatura de Valor Aduaneiro e Estatística) ──────────────

    #[test]
    fn nve_single_code_produces_correct_xml() {
        let item = sample_item().nve("AA0001");
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<NVE>AA0001</NVE>"));
        // NVE must appear after NCM
        let ncm_pos = result.xml.find("<NCM>").expect("<NCM> must exist");
        let nve_pos = result
            .xml
            .find("<NVE>AA0001</NVE>")
            .expect("<NVE> must exist");
        assert!(nve_pos > ncm_pos, "NVE must come after NCM");
    }

    #[test]
    fn nve_multiple_codes_produces_correct_xml() {
        let item = sample_item().nve("AA0001").nve("BB0002").nve("CC0003");
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<NVE>AA0001</NVE>"));
        assert!(result.xml.contains("<NVE>BB0002</NVE>"));
        assert!(result.xml.contains("<NVE>CC0003</NVE>"));
        // Verify order: AA0001 before BB0002 before CC0003
        let pos_a = result.xml.find("<NVE>AA0001</NVE>").expect("AA0001");
        let pos_b = result.xml.find("<NVE>BB0002</NVE>").expect("BB0002");
        let pos_c = result.xml.find("<NVE>CC0003</NVE>").expect("CC0003");
        assert!(pos_a < pos_b, "NVE codes must preserve insertion order");
        assert!(pos_b < pos_c, "NVE codes must preserve insertion order");
    }

    #[test]
    fn nve_eight_codes_is_valid() {
        let item = sample_item()
            .nve("AA0001")
            .nve("AA0002")
            .nve("AA0003")
            .nve("AA0004")
            .nve("AA0005")
            .nve("AA0006")
            .nve("AA0007")
            .nve("AA0008");
        let data = sample_build_data();
        let result = build_det(&item, &data);
        assert!(result.is_ok(), "8 NVE codes should be valid");
        let xml = result.expect("valid").xml;
        assert_eq!(xml.matches("<NVE>").count(), 8);
    }

    #[test]
    fn nve_nine_codes_returns_error() {
        let item = sample_item()
            .nve("AA0001")
            .nve("AA0002")
            .nve("AA0003")
            .nve("AA0004")
            .nve("AA0005")
            .nve("AA0006")
            .nve("AA0007")
            .nve("AA0008")
            .nve("AA0009");
        let data = sample_build_data();
        let result = build_det(&item, &data);
        assert!(result.is_err(), "9 NVE codes should be rejected");
        let err = result.unwrap_err();
        assert_eq!(
            err,
            FiscalError::InvalidTaxData("Item 1: NVE limited to 8 entries, got 9".to_string())
        );
    }

    #[test]
    fn nve_empty_vec_produces_no_nve_tags() {
        let item = sample_item();
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(!result.xml.contains("<NVE>"));
    }

    #[test]
    fn nve_appears_before_cest() {
        let item = sample_item().nve("AA0001").cest("1234567");
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        let nve_pos = result
            .xml
            .find("<NVE>AA0001</NVE>")
            .expect("<NVE> must exist");
        let cest_pos = result.xml.find("<CEST>").expect("<CEST> must exist");
        assert!(nve_pos < cest_pos, "NVE must come before CEST");
    }

    // ── gCred (crédito presumido ICMS) ──────────────────────────────────────

    #[test]
    fn gcred_single_with_value_produces_correct_xml() {
        let gc = GCredData::new("SP000001", Rate4(50000)).v_cred_presumido(Cents(1500));
        let item = sample_item().g_cred(vec![gc]);
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains(
            "<gCred><cCredPresumido>SP000001</cCredPresumido>\
             <pCredPresumido>5.0000</pCredPresumido>\
             <vCredPresumido>15.00</vCredPresumido></gCred>"
        ));
    }

    #[test]
    fn gcred_without_value_omits_v_cred_presumido() {
        let gc = GCredData::new("RJ000002", Rate4(120000));
        let item = sample_item().g_cred(vec![gc]);
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains(
            "<gCred>\
                <cCredPresumido>RJ000002</cCredPresumido>\
                <pCredPresumido>12.0000</pCredPresumido>\
            </gCred>"
        ));
        assert!(!result.xml.contains("<vCredPresumido>"));
    }

    #[test]
    fn gcred_multiple_entries_up_to_four() {
        let entries = vec![
            GCredData::new("SP000001", Rate4(10000)).v_cred_presumido(Cents(100)),
            GCredData::new("SP000002", Rate4(20000)).v_cred_presumido(Cents(200)),
            GCredData::new("SP000003", Rate4(30000)).v_cred_presumido(Cents(300)),
            GCredData::new("SP000004", Rate4(40000)).v_cred_presumido(Cents(400)),
        ];
        let item = sample_item().g_cred(entries);
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(
            result
                .xml
                .contains("<cCredPresumido>SP000001</cCredPresumido>")
        );
        assert!(
            result
                .xml
                .contains("<cCredPresumido>SP000002</cCredPresumido>")
        );
        assert!(
            result
                .xml
                .contains("<cCredPresumido>SP000003</cCredPresumido>")
        );
        assert!(
            result
                .xml
                .contains("<cCredPresumido>SP000004</cCredPresumido>")
        );
    }

    #[test]
    fn gcred_truncates_at_four_entries() {
        let entries = vec![
            GCredData::new("SP000001", Rate4(10000)),
            GCredData::new("SP000002", Rate4(20000)),
            GCredData::new("SP000003", Rate4(30000)),
            GCredData::new("SP000004", Rate4(40000)),
            GCredData::new("SP000005", Rate4(50000)),
        ];
        let item = sample_item().g_cred(entries);
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(
            result
                .xml
                .contains("<cCredPresumido>SP000004</cCredPresumido>")
        );
        assert!(
            !result
                .xml
                .contains("<cCredPresumido>SP000005</cCredPresumido>")
        );
    }

    #[test]
    fn gcred_positioned_after_cbenef_before_cfop() {
        let gc = GCredData::new("MG000001", Rate4(50000)).v_cred_presumido(Cents(1000));
        let item = sample_item().c_benef("SEM CBENEF").g_cred(vec![gc]);
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        let cbenef_pos = result.xml.find("<cBenef>").expect("cBenef should exist");
        let gcred_pos = result.xml.find("<gCred>").expect("gCred should exist");
        let cfop_pos = result.xml.find("<CFOP>").expect("CFOP should exist");

        assert!(gcred_pos > cbenef_pos, "gCred must come after cBenef");
        assert!(gcred_pos < cfop_pos, "gCred must come before CFOP");
    }

    #[test]
    fn gcred_empty_vec_produces_no_gcred_tags() {
        let item = sample_item();
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(!result.xml.contains("<gCred>"));
    }

    // ── Helper: Normal tax regime build data ─────────────────────────────

    fn normal_build_data() -> InvoiceBuildData {
        let mut data = sample_build_data();
        data.issuer.tax_regime = TaxRegime::Normal;
        data
    }

    fn pl010_build_data() -> InvoiceBuildData {
        let mut data = sample_build_data();
        data.schema_version = crate::types::SchemaVersion::PL010;
        data
    }

    // ── CSOSN variants (Simples Nacional) ────────────────────────────────

    #[test]
    fn csosn_101_produces_correct_xml() {
        let item = InvoiceItemData::new(
            1,
            "001",
            "Produto",
            "27101259",
            "5102",
            "UN",
            1.0,
            Cents(1000),
            Cents(1000),
            "101",
            Rate(1800),
            Cents(180),
            "99",
            "99",
        )
        .icms_p_cred_sn(Rate(500))
        .icms_v_cred_icms_sn(Cents(50));
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<ICMSSN101>"));
        assert!(result.xml.contains("<CSOSN>101</CSOSN>"));
        assert!(result.xml.contains("<pCredSN>"));
        assert!(result.xml.contains("<vCredICMSSN>"));
    }

    #[test]
    fn csosn_101_missing_p_cred_sn_returns_error() {
        let item = InvoiceItemData::new(
            1,
            "001",
            "Produto",
            "27101259",
            "5102",
            "UN",
            1.0,
            Cents(1000),
            Cents(1000),
            "101",
            Rate(0),
            Cents(0),
            "99",
            "99",
        )
        .icms_v_cred_icms_sn(Cents(50));
        let data = sample_build_data();
        let result = build_det(&item, &data);
        assert!(result.is_err());
    }

    #[test]
    fn csosn_101_missing_v_cred_icms_sn_returns_error() {
        let item = InvoiceItemData::new(
            1,
            "001",
            "Produto",
            "27101259",
            "5102",
            "UN",
            1.0,
            Cents(1000),
            Cents(1000),
            "101",
            Rate(0),
            Cents(0),
            "99",
            "99",
        )
        .icms_p_cred_sn(Rate(500));
        let data = sample_build_data();
        let result = build_det(&item, &data);
        assert!(result.is_err());
    }

    #[test]
    fn csosn_empty_defaults_to_102() {
        // When icms_cst is empty for Simples, it should default to "102"
        let item = InvoiceItemData::new(
            1,
            "001",
            "Produto",
            "27101259",
            "5102",
            "UN",
            1.0,
            Cents(1000),
            Cents(1000),
            "",
            Rate(0),
            Cents(0),
            "99",
            "99",
        );
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<ICMSSN102>"));
        assert!(result.xml.contains("<CSOSN>102</CSOSN>"));
    }

    #[test]
    fn csosn_103_produces_correct_xml() {
        let item = InvoiceItemData::new(
            1,
            "001",
            "Produto",
            "27101259",
            "5102",
            "UN",
            1.0,
            Cents(1000),
            Cents(1000),
            "103",
            Rate(0),
            Cents(0),
            "99",
            "99",
        );
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");
        // 102, 103, 300, 400 all share the ICMSSN102 tag name
        assert!(result.xml.contains("<ICMSSN102>"));
        assert!(result.xml.contains("<CSOSN>103</CSOSN>"));
    }

    #[test]
    fn csosn_300_produces_correct_xml() {
        let item = InvoiceItemData::new(
            1,
            "001",
            "Produto",
            "27101259",
            "5102",
            "UN",
            1.0,
            Cents(1000),
            Cents(1000),
            "300",
            Rate(0),
            Cents(0),
            "99",
            "99",
        );
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");
        assert!(result.xml.contains("<ICMSSN102>"));
        assert!(result.xml.contains("<CSOSN>300</CSOSN>"));
    }

    #[test]
    fn csosn_400_produces_correct_xml() {
        let item = InvoiceItemData::new(
            1,
            "001",
            "Produto",
            "27101259",
            "5102",
            "UN",
            1.0,
            Cents(1000),
            Cents(1000),
            "400",
            Rate(0),
            Cents(0),
            "99",
            "99",
        );
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");
        assert!(result.xml.contains("<ICMSSN102>"));
        assert!(result.xml.contains("<CSOSN>400</CSOSN>"));
    }

    #[test]
    fn csosn_201_produces_correct_xml() {
        let item = InvoiceItemData::new(
            1,
            "001",
            "Produto",
            "27101259",
            "5102",
            "UN",
            1.0,
            Cents(1000),
            Cents(1000),
            "201",
            Rate(1800),
            Cents(180),
            "99",
            "99",
        )
        .icms_mod_bc_st(4)
        .icms_v_bc_st(Cents(1200))
        .icms_p_icms_st(Rate(1200))
        .icms_v_icms_st(Cents(144))
        .icms_p_mva_st(Rate(5000))
        .icms_red_bc_st(Rate(1000))
        .icms_v_bc_fcp_st(Cents(1200))
        .icms_p_fcp_st(Rate(200))
        .icms_v_fcp_st(Cents(24))
        .icms_p_cred_sn(Rate(500))
        .icms_v_cred_icms_sn(Cents(50));
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<ICMSSN201>"));
        assert!(result.xml.contains("<CSOSN>201</CSOSN>"));
        assert!(result.xml.contains("<modBCST>4</modBCST>"));
        assert!(result.xml.contains("<vBCST>12.00</vBCST>"));
        assert!(result.xml.contains("<pICMSST>"));
        assert!(result.xml.contains("<vICMSST>"));
        assert!(result.xml.contains("<pMVAST>"));
        assert!(result.xml.contains("<pRedBCST>"));
    }

    #[test]
    fn csosn_202_produces_correct_xml() {
        let item = InvoiceItemData::new(
            1,
            "001",
            "Produto",
            "27101259",
            "5102",
            "UN",
            1.0,
            Cents(1000),
            Cents(1000),
            "202",
            Rate(0),
            Cents(0),
            "99",
            "99",
        )
        .icms_mod_bc_st(4)
        .icms_v_bc_st(Cents(1200))
        .icms_p_icms_st(Rate(1200))
        .icms_v_icms_st(Cents(144))
        .icms_p_mva_st(Rate(5000))
        .icms_red_bc_st(Rate(1000))
        .icms_v_bc_fcp_st(Cents(1200))
        .icms_p_fcp_st(Rate(200))
        .icms_v_fcp_st(Cents(24));
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<ICMSSN202>"));
        assert!(result.xml.contains("<CSOSN>202</CSOSN>"));
        assert!(result.xml.contains("<modBCST>4</modBCST>"));
    }

    #[test]
    fn csosn_203_produces_correct_xml() {
        let item = InvoiceItemData::new(
            1,
            "001",
            "Produto",
            "27101259",
            "5102",
            "UN",
            1.0,
            Cents(1000),
            Cents(1000),
            "203",
            Rate(0),
            Cents(0),
            "99",
            "99",
        )
        .icms_mod_bc_st(4)
        .icms_v_bc_st(Cents(1200))
        .icms_p_icms_st(Rate(1200))
        .icms_v_icms_st(Cents(144))
        .icms_p_mva_st(Rate(5000))
        .icms_red_bc_st(Rate(1000))
        .icms_v_bc_fcp_st(Cents(1200))
        .icms_p_fcp_st(Rate(200))
        .icms_v_fcp_st(Cents(24));
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        // 202 and 203 share the ICMSSN202 tag name
        assert!(result.xml.contains("<ICMSSN202>"));
        assert!(result.xml.contains("<CSOSN>203</CSOSN>"));
        assert!(result.xml.contains("<modBCST>4</modBCST>"));
    }

    #[test]
    fn csosn_500_produces_correct_xml() {
        let item = InvoiceItemData::new(
            1,
            "001",
            "Produto",
            "27101259",
            "5102",
            "UN",
            1.0,
            Cents(1000),
            Cents(1000),
            "500",
            Rate(0),
            Cents(0),
            "99",
            "99",
        )
        .icms_v_icms_substituto(Cents(200));
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<ICMSSN500>"));
        assert!(result.xml.contains("<CSOSN>500</CSOSN>"));
        assert!(result.xml.contains("<vICMSSubstituto>"));
    }

    #[test]
    fn csosn_900_produces_correct_xml() {
        let item = InvoiceItemData::new(
            1,
            "001",
            "Produto",
            "27101259",
            "5102",
            "UN",
            1.0,
            Cents(1000),
            Cents(1000),
            "900",
            Rate(1800),
            Cents(180),
            "99",
            "99",
        )
        .icms_mod_bc(3)
        .icms_red_bc(Rate(1000))
        .icms_mod_bc_st(4)
        .icms_p_mva_st(Rate(5000))
        .icms_red_bc_st(Rate(1000))
        .icms_v_bc_st(Cents(1200))
        .icms_p_icms_st(Rate(1200))
        .icms_v_icms_st(Cents(144))
        .icms_v_bc_fcp_st(Cents(1200))
        .icms_p_fcp_st(Rate(200))
        .icms_v_fcp_st(Cents(24))
        .icms_p_cred_sn(Rate(500))
        .icms_v_cred_icms_sn(Cents(50));
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<ICMSSN900>"));
        assert!(result.xml.contains("<CSOSN>900</CSOSN>"));
        assert!(result.xml.contains("<modBC>3</modBC>"));
    }

    #[test]
    fn csosn_unsupported_returns_error() {
        let item = InvoiceItemData::new(
            1,
            "001",
            "Produto",
            "27101259",
            "5102",
            "UN",
            1.0,
            Cents(1000),
            Cents(1000),
            "999",
            Rate(0),
            Cents(0),
            "99",
            "99",
        );
        let data = sample_build_data();
        let result = build_det(&item, &data);
        assert!(result.is_err());
        let err = result.unwrap_err();
        assert!(
            matches!(err, FiscalError::UnsupportedIcmsCsosn(ref c) if c == "999"),
            "expected UnsupportedIcmsCsosn, got {:?}",
            err
        );
    }

    // ── ICMS CST variants (Normal tax regime) ────────────────────────────

    #[test]
    fn cst_10_produces_correct_xml() {
        let item = InvoiceItemData::new(
            1,
            "001",
            "Produto",
            "27101259",
            "5102",
            "UN",
            1.0,
            Cents(1000),
            Cents(1000),
            "10",
            Rate(1800),
            Cents(180),
            "99",
            "99",
        )
        .icms_mod_bc_st(4)
        .icms_v_bc_st(Cents(1200))
        .icms_p_icms_st(Rate(1200))
        .icms_v_icms_st(Cents(144))
        .icms_v_bc_fcp(Cents(1000))
        .icms_p_fcp(Rate(200))
        .icms_v_fcp(Cents(20))
        .icms_p_mva_st(Rate(5000))
        .icms_red_bc_st(Rate(1000))
        .icms_v_bc_fcp_st(Cents(1200))
        .icms_p_fcp_st(Rate(200))
        .icms_v_fcp_st(Cents(24));
        let data = normal_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<ICMS10>"));
        assert!(result.xml.contains("<CST>10</CST>"));
        assert!(result.xml.contains("<modBCST>4</modBCST>"));
        assert!(result.xml.contains("<vBCST>12.00</vBCST>"));
        assert!(result.xml.contains("<pICMSST>"));
        assert!(result.xml.contains("<vICMSST>"));
    }

    #[test]
    fn cst_20_produces_correct_xml() {
        let item = InvoiceItemData::new(
            1,
            "001",
            "Produto",
            "27101259",
            "5102",
            "UN",
            1.0,
            Cents(1000),
            Cents(1000),
            "20",
            Rate(1800),
            Cents(180),
            "99",
            "99",
        )
        .icms_mod_bc(3)
        .icms_red_bc(Rate(2000))
        .icms_v_bc_fcp(Cents(1000))
        .icms_p_fcp(Rate(200))
        .icms_v_fcp(Cents(20))
        .icms_v_icms_deson(Cents(50))
        .icms_mot_des_icms(9)
        .icms_ind_deduz_deson("1");
        let data = normal_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<ICMS20>"));
        assert!(result.xml.contains("<CST>20</CST>"));
        assert!(result.xml.contains("<pRedBC>"));
        assert!(result.xml.contains("<vICMSDeson>"));
        assert!(result.xml.contains("<motDesICMS>9</motDesICMS>"));
        assert!(result.xml.contains("<indDeduzDeson>1</indDeduzDeson>"));
        assert!(result.ind_deduz_deson);
    }

    #[test]
    fn cst_30_produces_correct_xml() {
        let item = InvoiceItemData::new(
            1,
            "001",
            "Produto",
            "27101259",
            "5102",
            "UN",
            1.0,
            Cents(1000),
            Cents(1000),
            "30",
            Rate(0),
            Cents(0),
            "99",
            "99",
        )
        .icms_mod_bc_st(4)
        .icms_v_bc_st(Cents(1200))
        .icms_p_icms_st(Rate(1200))
        .icms_v_icms_st(Cents(144))
        .icms_p_mva_st(Rate(5000))
        .icms_red_bc_st(Rate(1000))
        .icms_v_bc_fcp_st(Cents(1200))
        .icms_p_fcp_st(Rate(200))
        .icms_v_fcp_st(Cents(24))
        .icms_v_icms_deson(Cents(50))
        .icms_mot_des_icms(9)
        .icms_ind_deduz_deson("1");
        let data = normal_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<ICMS30>"));
        assert!(result.xml.contains("<CST>30</CST>"));
        assert!(result.xml.contains("<modBCST>4</modBCST>"));
        assert!(result.xml.contains("<vICMSDeson>"));
        assert!(result.xml.contains("<motDesICMS>9</motDesICMS>"));
    }

    #[test]
    fn cst_40_produces_correct_xml() {
        let item = InvoiceItemData::new(
            1,
            "001",
            "Produto",
            "27101259",
            "5102",
            "UN",
            1.0,
            Cents(1000),
            Cents(1000),
            "40",
            Rate(0),
            Cents(0),
            "99",
            "99",
        )
        .icms_v_icms_deson(Cents(100))
        .icms_mot_des_icms(1)
        .icms_ind_deduz_deson("1");
        let data = normal_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<ICMS40>"));
        assert!(result.xml.contains("<CST>40</CST>"));
        assert!(result.xml.contains("<vICMSDeson>"));
        assert!(result.xml.contains("<motDesICMS>1</motDesICMS>"));
    }

    #[test]
    fn cst_41_produces_correct_xml() {
        let item = InvoiceItemData::new(
            1,
            "001",
            "Produto",
            "27101259",
            "5102",
            "UN",
            1.0,
            Cents(1000),
            Cents(1000),
            "41",
            Rate(0),
            Cents(0),
            "99",
            "99",
        )
        .icms_v_icms_deson(Cents(100))
        .icms_mot_des_icms(1)
        .icms_ind_deduz_deson("1");
        let data = normal_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        // 40, 41, 50 all share the ICMS40 tag name
        assert!(result.xml.contains("<ICMS40>"));
        assert!(result.xml.contains("<CST>41</CST>"));
        assert!(result.xml.contains("<vICMSDeson>"));
    }

    #[test]
    fn cst_50_produces_correct_xml() {
        let item = InvoiceItemData::new(
            1,
            "001",
            "Produto",
            "27101259",
            "5102",
            "UN",
            1.0,
            Cents(1000),
            Cents(1000),
            "50",
            Rate(0),
            Cents(0),
            "99",
            "99",
        )
        .icms_v_icms_deson(Cents(100))
        .icms_mot_des_icms(1)
        .icms_ind_deduz_deson("1");
        let data = normal_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        // 40, 41, 50 all share the ICMS40 tag name
        assert!(result.xml.contains("<ICMS40>"));
        assert!(result.xml.contains("<CST>50</CST>"));
        assert!(result.xml.contains("<vICMSDeson>"));
    }

    #[test]
    fn cst_51_produces_correct_xml() {
        let item = InvoiceItemData::new(
            1,
            "001",
            "Produto",
            "27101259",
            "5102",
            "UN",
            1.0,
            Cents(1000),
            Cents(1000),
            "51",
            Rate(1800),
            Cents(180),
            "99",
            "99",
        )
        .icms_mod_bc(3)
        .icms_red_bc(Rate(1000))
        .icms_v_bc_fcp(Cents(1000))
        .icms_p_fcp(Rate(200))
        .icms_v_fcp(Cents(20));
        let data = normal_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<ICMS51>"));
        assert!(result.xml.contains("<CST>51</CST>"));
        assert!(result.xml.contains("<modBC>3</modBC>"));
        assert!(result.xml.contains("<pRedBC>"));
        assert!(result.xml.contains("<vICMS>"));
    }

    #[test]
    fn cst_60_produces_correct_xml() {
        let item = InvoiceItemData::new(
            1,
            "001",
            "Produto",
            "27101259",
            "5102",
            "UN",
            1.0,
            Cents(1000),
            Cents(1000),
            "60",
            Rate(0),
            Cents(0),
            "99",
            "99",
        )
        .icms_v_icms_substituto(Cents(200));
        let data = normal_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<ICMS60>"));
        assert!(result.xml.contains("<CST>60</CST>"));
        assert!(result.xml.contains("<vICMSSubstituto>"));
    }

    #[test]
    fn cst_70_produces_correct_xml() {
        let item = InvoiceItemData::new(
            1,
            "001",
            "Produto",
            "27101259",
            "5102",
            "UN",
            1.0,
            Cents(1000),
            Cents(1000),
            "70",
            Rate(1800),
            Cents(180),
            "99",
            "99",
        )
        .icms_mod_bc(3)
        .icms_red_bc(Rate(2000))
        .icms_mod_bc_st(4)
        .icms_v_bc_st(Cents(1200))
        .icms_p_icms_st(Rate(1200))
        .icms_v_icms_st(Cents(144))
        .icms_v_bc_fcp(Cents(1000))
        .icms_p_fcp(Rate(200))
        .icms_v_fcp(Cents(20))
        .icms_p_mva_st(Rate(5000))
        .icms_red_bc_st(Rate(1000))
        .icms_v_bc_fcp_st(Cents(1200))
        .icms_p_fcp_st(Rate(200))
        .icms_v_fcp_st(Cents(24))
        .icms_v_icms_deson(Cents(50))
        .icms_mot_des_icms(9)
        .icms_ind_deduz_deson("1");
        let data = normal_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<ICMS70>"));
        assert!(result.xml.contains("<CST>70</CST>"));
        assert!(result.xml.contains("<pRedBC>"));
        assert!(result.xml.contains("<modBCST>4</modBCST>"));
        assert!(result.xml.contains("<vICMSDeson>"));
    }

    #[test]
    fn cst_90_produces_correct_xml() {
        let item = InvoiceItemData::new(
            1,
            "001",
            "Produto",
            "27101259",
            "5102",
            "UN",
            1.0,
            Cents(1000),
            Cents(1000),
            "90",
            Rate(1800),
            Cents(180),
            "99",
            "99",
        )
        .icms_mod_bc(3)
        .icms_red_bc(Rate(1000))
        .icms_v_bc_fcp(Cents(1000))
        .icms_p_fcp(Rate(200))
        .icms_v_fcp(Cents(20))
        .icms_mod_bc_st(4)
        .icms_p_mva_st(Rate(5000))
        .icms_red_bc_st(Rate(1000))
        .icms_v_bc_st(Cents(1200))
        .icms_p_icms_st(Rate(1200))
        .icms_v_icms_st(Cents(144))
        .icms_v_bc_fcp_st(Cents(1200))
        .icms_p_fcp_st(Rate(200))
        .icms_v_fcp_st(Cents(24))
        .icms_v_icms_deson(Cents(50))
        .icms_mot_des_icms(9)
        .icms_ind_deduz_deson("1");
        let data = normal_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<ICMS90>"));
        assert!(result.xml.contains("<CST>90</CST>"));
        assert!(result.xml.contains("<modBC>3</modBC>"));
        assert!(result.xml.contains("<modBCST>4</modBCST>"));
        assert!(result.xml.contains("<vICMSDeson>"));
    }

    #[test]
    fn cst_unsupported_returns_error() {
        let item = InvoiceItemData::new(
            1,
            "001",
            "Produto",
            "27101259",
            "5102",
            "UN",
            1.0,
            Cents(1000),
            Cents(1000),
            "99",
            Rate(0),
            Cents(0),
            "99",
            "99",
        );
        let data = normal_build_data();
        let result = build_det(&item, &data);
        assert!(result.is_err());
        let err = result.unwrap_err();
        assert!(
            matches!(err, FiscalError::UnsupportedIcmsCst(ref c) if c == "99"),
            "expected UnsupportedIcmsCst, got {:?}",
            err
        );
    }

    // ── IPI (optional) ───────────────────────────────────────────────────

    #[test]
    fn ipi_produces_correct_xml() {
        let item = sample_item()
            .ipi_cst("50")
            .ipi_c_enq("999")
            .ipi_v_bc(Cents(10000))
            .ipi_p_ipi(Rate(500))
            .ipi_v_ipi(Cents(500));
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<IPI>"));
        assert!(result.xml.contains("<CST>50</CST>"));
        assert!(result.xml.contains("<cEnq>999</cEnq>"));
        assert!(result.xml.contains("<vIPI>5.00</vIPI>"));
        assert_eq!(result.v_ipi, 500);
    }

    #[test]
    fn ipi_default_c_enq_when_missing() {
        let item = sample_item()
            .ipi_cst("50")
            .ipi_v_bc(Cents(10000))
            .ipi_p_ipi(Rate(500))
            .ipi_v_ipi(Cents(500));
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<cEnq>999</cEnq>"));
    }

    #[test]
    fn ipi_with_quantity_based() {
        let item = sample_item()
            .ipi_cst("50")
            .ipi_q_unid(100)
            .ipi_v_unid(50)
            .ipi_v_ipi(Cents(5000));
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<IPI>"));
        assert_eq!(result.v_ipi, 5000);
    }

    #[test]
    fn no_ipi_when_cst_absent() {
        let item = sample_item();
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(!result.xml.contains("<IPI>"));
        assert_eq!(result.v_ipi, 0);
    }

    // ── II (Import Tax) ──────────────────────────────────────────────────

    #[test]
    fn ii_produces_correct_xml() {
        let item = sample_item()
            .ii_v_bc(Cents(50000))
            .ii_v_desp_adu(Cents(5000))
            .ii_v_ii(Cents(10000))
            .ii_v_iof(Cents(2000));
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<II>"));
        assert!(result.xml.contains("<vBC>500.00</vBC>"));
        assert!(result.xml.contains("<vDespAdu>50.00</vDespAdu>"));
        assert!(result.xml.contains("<vII>100.00</vII>"));
        assert!(result.xml.contains("<vIOF>20.00</vIOF>"));
        assert_eq!(result.v_ii, 10000);
    }

    #[test]
    fn no_ii_when_absent() {
        let item = sample_item();
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(!result.xml.contains("<II>"));
        assert_eq!(result.v_ii, 0);
    }

    // ── PIS-ST / COFINS-ST ──────────────────────────────────────────────

    #[test]
    fn pis_st_replaces_pis_and_accumulates_when_ind_soma_1() {
        use crate::tax_pis_cofins_ipi::PisStData;
        let pis_st = PisStData::new(Cents(500))
            .v_bc(Cents(10000))
            .p_pis(Rate4(16500))
            .ind_soma_pis_st(1);
        let item = sample_item().pis_st(pis_st);
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<PISST>"));
        assert!(!result.xml.contains("<PISAliq>"));
        assert_eq!(result.v_pis_st, 500);
    }

    #[test]
    fn pis_st_does_not_accumulate_when_ind_soma_0() {
        use crate::tax_pis_cofins_ipi::PisStData;
        let pis_st = PisStData::new(Cents(500))
            .v_bc(Cents(10000))
            .p_pis(Rate4(16500))
            .ind_soma_pis_st(0);
        let item = sample_item().pis_st(pis_st);
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<PISST>"));
        assert_eq!(result.v_pis_st, 0);
    }

    #[test]
    fn cofins_st_replaces_cofins_and_accumulates_when_ind_soma_1() {
        use crate::tax_pis_cofins_ipi::CofinsStData;
        let cofins_st = CofinsStData::new(Cents(750))
            .v_bc(Cents(10000))
            .p_cofins(Rate4(76000))
            .ind_soma_cofins_st(1);
        let item = sample_item().cofins_st(cofins_st);
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<COFINSST>"));
        assert!(!result.xml.contains("<COFINSAliq>"));
        assert_eq!(result.v_cofins_st, 750);
    }

    #[test]
    fn cofins_st_does_not_accumulate_when_ind_soma_0() {
        use crate::tax_pis_cofins_ipi::CofinsStData;
        let cofins_st = CofinsStData::new(Cents(750))
            .v_bc(Cents(10000))
            .p_cofins(Rate4(76000))
            .ind_soma_cofins_st(0);
        let item = sample_item().cofins_st(cofins_st);
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<COFINSST>"));
        assert_eq!(result.v_cofins_st, 0);
    }

    // ── IS / IBS-CBS (PL010 schema) ─────────────────────────────────────

    #[test]
    fn is_data_emitted_with_pl010_schema() {
        use crate::tax_is::IsData;
        let is = IsData::new("00", "001", "5.00");
        let item = sample_item().is_data(is);
        let data = pl010_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<IS>"));
    }

    #[test]
    fn is_data_not_emitted_with_pl009_schema() {
        use crate::tax_is::IsData;
        let is = IsData::new("00", "001", "5.00");
        let item = sample_item().is_data(is);
        let data = sample_build_data(); // PL009
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(!result.xml.contains("<IS>"));
    }

    #[test]
    fn ibs_cbs_data_emitted_with_pl010_schema() {
        use crate::tax_ibs_cbs::IbsCbsData;
        let ibs_cbs = IbsCbsData::new("00", "001");
        let item = sample_item().ibs_cbs(ibs_cbs);
        let data = pl010_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<IBSCBS>"));
    }

    // ── CEST with indEscala and CNPJFab ─────────────────────────────────

    #[test]
    fn cest_with_ind_escala_and_cnpj_fab() {
        let item = sample_item()
            .cest("1234567")
            .cest_ind_escala("S")
            .cest_cnpj_fab("12345678000199");
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<CEST>1234567</CEST>"));
        assert!(result.xml.contains("<indEscala>S</indEscala>"));
        assert!(result.xml.contains("<CNPJFab>12345678000199</CNPJFab>"));
    }

    // ── EXTIPI ──────────────────────────────────────────────────────────

    #[test]
    fn extipi_produces_correct_xml() {
        let item = sample_item().extipi("01");
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<EXTIPI>01</EXTIPI>"));
        // EXTIPI must appear after NCM and before CFOP
        let ncm_pos = result.xml.find("<NCM>").unwrap();
        let extipi_pos = result.xml.find("<EXTIPI>").unwrap();
        let cfop_pos = result.xml.find("<CFOP>").unwrap();
        assert!(extipi_pos > ncm_pos);
        assert!(extipi_pos < cfop_pos);
    }

    // ── nItemPed, nFCI ──────────────────────────────────────────────────

    #[test]
    fn n_item_ped_produces_correct_xml() {
        let item = sample_item().n_item_ped("5");
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<nItemPed>5</nItemPed>"));
    }

    #[test]
    fn n_fci_produces_correct_xml() {
        let item = sample_item().n_fci("B01F70AF-10BF-4B1F-848C-65FF57F616FE");
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(
            result
                .xml
                .contains("<nFCI>B01F70AF-10BF-4B1F-848C-65FF57F616FE</nFCI>")
        );
    }

    // ── Veículo (veicProd) ──────────────────────────────────────────────

    #[test]
    fn veic_prod_produces_correct_xml() {
        let veic = VeicProdData::new(
            "1",
            "9BWZZZ377VT004251",
            "1",
            "PRATA",
            "100",
            "1600",
            "1050",
            "1250",
            "ABC123",
            "1",
            "MOT123",
            "1500",
            "2600",
            "2025",
            "2025",
            "M",
            "06",
            "1",
            "R",
            "1",
            "MOD001",
            "02",
            "5",
            "0",
        );
        let item = sample_item().veic_prod(veic);
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<veicProd>"));
        assert!(result.xml.contains("<tpOp>1</tpOp>"));
        assert!(result.xml.contains("<chassi>9BWZZZ377VT004251</chassi>"));
        assert!(result.xml.contains("<cCor>1</cCor>"));
        assert!(result.xml.contains("<xCor>PRATA</xCor>"));
        assert!(result.xml.contains("<pot>100</pot>"));
        assert!(result.xml.contains("<cilin>1600</cilin>"));
        assert!(result.xml.contains("<pesoL>1050</pesoL>"));
        assert!(result.xml.contains("<pesoB>1250</pesoB>"));
        assert!(result.xml.contains("<nSerie>ABC123</nSerie>"));
        assert!(result.xml.contains("<tpComb>1</tpComb>"));
        assert!(result.xml.contains("<nMotor>MOT123</nMotor>"));
        assert!(result.xml.contains("<CMT>1500</CMT>"));
        assert!(result.xml.contains("<dist>2600</dist>"));
        assert!(result.xml.contains("<anoMod>2025</anoMod>"));
        assert!(result.xml.contains("<anoFab>2025</anoFab>"));
        assert!(result.xml.contains("<tpPint>M</tpPint>"));
        assert!(result.xml.contains("<tpVeic>06</tpVeic>"));
        assert!(result.xml.contains("<espVeic>1</espVeic>"));
        assert!(result.xml.contains("<VIN>R</VIN>"));
        assert!(result.xml.contains("<condVeic>1</condVeic>"));
        assert!(result.xml.contains("<cMod>MOD001</cMod>"));
        assert!(result.xml.contains("<cCorDENATRAN>02</cCorDENATRAN>"));
        assert!(result.xml.contains("<lota>5</lota>"));
        assert!(result.xml.contains("<tpRest>0</tpRest>"));
        assert!(result.xml.contains("</veicProd>"));
    }

    // ── Medicamento (med) ───────────────────────────────────────────────

    #[test]
    fn med_with_anvisa_code() {
        let med = MedData::new(Cents(5000)).c_prod_anvisa("1234567890123");
        let item = sample_item().med(med);
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<med>"));
        assert!(
            result
                .xml
                .contains("<cProdANVISA>1234567890123</cProdANVISA>")
        );
        assert!(result.xml.contains("<vPMC>50.00</vPMC>"));
        assert!(result.xml.contains("</med>"));
    }

    #[test]
    fn med_with_exemption_reason() {
        let med = MedData::new(Cents(3000)).x_motivo_isencao("Medicamento isento de registro");
        let item = sample_item().med(med);
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<med>"));
        assert!(
            result
                .xml
                .contains("<xMotivoIsencao>Medicamento isento de registro</xMotivoIsencao>")
        );
        assert!(result.xml.contains("<vPMC>30.00</vPMC>"));
        assert!(!result.xml.contains("<cProdANVISA>"));
    }

    // ── Arma (weapon) ───────────────────────────────────────────────────

    #[test]
    fn arma_single_produces_correct_xml() {
        let arma = ArmaData::new("0", "SN12345", "CN6789", "Pistola Taurus");
        let item = sample_item().arma(vec![arma]);
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<arma>"));
        assert!(result.xml.contains("<tpArma>0</tpArma>"));
        assert!(result.xml.contains("<nSerie>SN12345</nSerie>"));
        assert!(result.xml.contains("<nCano>CN6789</nCano>"));
        assert!(result.xml.contains("<descr>Pistola Taurus</descr>"));
        assert!(result.xml.contains("</arma>"));
    }

    #[test]
    fn arma_multiple_produces_multiple_elements() {
        let a1 = ArmaData::new("0", "SN001", "CN001", "Arma 1");
        let a2 = ArmaData::new("1", "SN002", "CN002", "Arma 2");
        let item = sample_item().arma(vec![a1, a2]);
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert_eq!(result.xml.matches("<arma>").count(), 2);
        assert!(result.xml.contains("<nSerie>SN001</nSerie>"));
        assert!(result.xml.contains("<nSerie>SN002</nSerie>"));
    }

    // ── nRECOPI ─────────────────────────────────────────────────────────

    #[test]
    fn n_recopi_produces_correct_xml() {
        let item = sample_item().n_recopi("20250000001234567890");
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(
            result
                .xml
                .contains("<nRECOPI>20250000001234567890</nRECOPI>")
        );
    }

    #[test]
    fn n_recopi_empty_not_emitted() {
        let item = sample_item().n_recopi("");
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(!result.xml.contains("<nRECOPI>"));
    }

    // ── Rastro (batch tracking) ─────────────────────────────────────────

    #[test]
    fn rastro_single_produces_correct_xml() {
        let r = RastroData::new("LOTE001", 10.5, "2025-01-01", "2026-01-01");
        let item = sample_item().rastro(vec![r]);
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<rastro>"));
        assert!(result.xml.contains("<nLote>LOTE001</nLote>"));
        assert!(result.xml.contains("<qLote>10.500</qLote>"));
        assert!(result.xml.contains("<dFab>2025-01-01</dFab>"));
        assert!(result.xml.contains("<dVal>2026-01-01</dVal>"));
        assert!(result.xml.contains("</rastro>"));
    }

    #[test]
    fn rastro_with_c_agreg() {
        let r = RastroData::new("LOTE002", 5.0, "2025-06-01", "2026-06-01").c_agreg("AGREG001");
        let item = sample_item().rastro(vec![r]);
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<cAgreg>AGREG001</cAgreg>"));
    }

    // ── obsItem with obsFisco ───────────────────────────────────────────

    #[test]
    fn obs_item_with_obs_cont_only() {
        use crate::types::{ObsField, ObsItemData};
        let obs = ObsItemData::new().obs_cont(ObsField::new("campo1", "texto1"));
        let item = sample_item().obs_item(obs);
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<obsItem>"));
        assert!(result.xml.contains("<obsCont xCampo=\"campo1\">"));
        assert!(result.xml.contains("<xTexto>texto1</xTexto>"));
        assert!(!result.xml.contains("<obsFisco"));
    }

    #[test]
    fn obs_item_with_obs_fisco() {
        use crate::types::{ObsField, ObsItemData};
        let obs = ObsItemData::new().obs_fisco(ObsField::new("campo_fisco", "texto_fisco"));
        let item = sample_item().obs_item(obs);
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<obsItem>"));
        assert!(result.xml.contains("<obsFisco xCampo=\"campo_fisco\">"));
        assert!(result.xml.contains("<xTexto>texto_fisco</xTexto>"));
    }

    #[test]
    fn obs_item_with_both_obs_cont_and_obs_fisco() {
        use crate::types::{ObsField, ObsItemData};
        let obs = ObsItemData::new()
            .obs_cont(ObsField::new("campo_cont", "texto_cont"))
            .obs_fisco(ObsField::new("campo_fisco", "texto_fisco"));
        let item = sample_item().obs_item(obs);
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<obsCont xCampo=\"campo_cont\">"));
        assert!(result.xml.contains("<obsFisco xCampo=\"campo_fisco\">"));
    }

    // ── DFeReferenciado ─────────────────────────────────────────────────

    #[test]
    fn dfe_referenciado_without_n_item() {
        use crate::types::DFeReferenciadoData;
        let dfe = DFeReferenciadoData::new("12345678901234567890123456789012345678901234");
        let item = sample_item().dfe_referenciado(dfe);
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<DFeReferenciado>"));
        assert!(
            result.xml.contains(
                "<chaveAcesso>12345678901234567890123456789012345678901234</chaveAcesso>"
            )
        );
        assert!(!result.xml.contains("<nItem>"));
    }

    #[test]
    fn dfe_referenciado_with_n_item() {
        use crate::types::DFeReferenciadoData;
        let dfe =
            DFeReferenciadoData::new("12345678901234567890123456789012345678901234").n_item("3");
        let item = sample_item().dfe_referenciado(dfe);
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<DFeReferenciado>"));
        assert!(result.xml.contains("<nItem>3</nItem>"));
    }

    // ── Homologation xProd substitution (NFC-e) ─────────────────────────

    #[test]
    fn nfce_homologation_substitutes_xprod_for_item_1() {
        let item = sample_item();
        let mut data = sample_build_data();
        data.model = InvoiceModel::Nfce;
        data.environment = SefazEnvironment::Homologation;
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains(HOMOLOGATION_XPROD));
    }

    #[test]
    fn nfce_homologation_does_not_substitute_for_item_2() {
        let mut item = sample_item();
        item.item_number = 2;
        let mut data = sample_build_data();
        data.model = InvoiceModel::Nfce;
        data.environment = SefazEnvironment::Homologation;
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(!result.xml.contains(HOMOLOGATION_XPROD));
        assert!(result.xml.contains("<xProd>Gasolina Comum</xProd>"));
    }

    // ── v_frete, v_seg, v_desc, v_outro ─────────────────────────────────

    #[test]
    fn optional_value_fields_in_det_result() {
        let item = sample_item()
            .v_frete(Cents(1000))
            .v_seg(Cents(500))
            .v_desc(Cents(200))
            .v_outro(Cents(300));
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<vFrete>10.00</vFrete>"));
        assert!(result.xml.contains("<vSeg>5.00</vSeg>"));
        assert!(result.xml.contains("<vDesc>2.00</vDesc>"));
        assert!(result.xml.contains("<vOutro>3.00</vOutro>"));
        assert_eq!(result.v_frete, 1000);
        assert_eq!(result.v_seg, 500);
        assert_eq!(result.v_desc, 200);
        assert_eq!(result.v_outro, 300);
    }

    // ── ind_tot override ────────────────────────────────────────────────

    #[test]
    fn ind_tot_zero_excludes_from_total() {
        let item = sample_item().ind_tot(0);
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<indTot>0</indTot>"));
        assert_eq!(result.ind_tot, 0);
    }

    // ── v_tot_trib ──────────────────────────────────────────────────────

    #[test]
    fn v_tot_trib_propagated_to_result() {
        let item = sample_item().v_tot_trib(Cents(1234));
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert_eq!(result.v_tot_trib, 1234);
    }

    // ── xPed ────────────────────────────────────────────────────────────

    #[test]
    fn x_ped_produces_correct_xml() {
        let item = sample_item().x_ped("PEDIDO-001");
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<xPed>PEDIDO-001</xPed>"));
    }

    // ── infAdProd ───────────────────────────────────────────────────────

    #[test]
    fn inf_ad_prod_produces_correct_xml() {
        let item = sample_item().inf_ad_prod("informacao adicional do produto");
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(
            result
                .xml
                .contains("<infAdProd>informacao adicional do produto</infAdProd>")
        );
    }

    // ── ind_deduz_deson ─────────────────────────────────────────────────

    #[test]
    fn ind_deduz_deson_true_when_set_to_1() {
        let item = InvoiceItemData::new(
            1,
            "001",
            "Produto",
            "27101259",
            "5102",
            "UN",
            1.0,
            Cents(1000),
            Cents(1000),
            "40",
            Rate(0),
            Cents(0),
            "99",
            "99",
        )
        .icms_v_icms_deson(Cents(100))
        .icms_mot_des_icms(1)
        .icms_ind_deduz_deson("1");
        let data = normal_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");
        assert!(result.ind_deduz_deson);
    }

    #[test]
    fn ind_deduz_deson_false_when_not_set() {
        let item = sample_item();
        let data = sample_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");
        assert!(!result.ind_deduz_deson);
    }

    // ── orig override ───────────────────────────────────────────────────

    #[test]
    fn custom_orig_used_in_icms() {
        let item = InvoiceItemData::new(
            1,
            "001",
            "Produto",
            "27101259",
            "5102",
            "UN",
            1.0,
            Cents(1000),
            Cents(1000),
            "00",
            Rate(1800),
            Cents(180),
            "99",
            "99",
        )
        .orig("1");
        let data = normal_build_data();
        let result = build_det(&item, &data).expect("build_det should succeed");

        assert!(result.xml.contains("<orig>1</orig>"));
    }
}