nmbrs-workload 0.3.0

// Copyright 2024-2026 Jonathan Shook
// SPDX-License-Identifier: Apache-2.0

//! Unified `report:` block — plots and tables under one schema.
//!
//! See SRD-46 (`docs/SRD/46_reports.md`) for the authoritative
//! design. This module owns:
//!
//! - The data model: [`Report`] / [`ReportGroup`] / [`ReportItem`]
//!   / [`Kind`] / [`Style`].
//! - The directive-string tokenizer that splits a group's body
//!   into items keyed by leading `plot <name>` / `table <name>`.
//! - The JSON sub-block parser for `series ... {…}` style
//!   overrides (strict JSON only — relies on the existing rule
//!   that Polydat `{...}` is unambiguously not JSON).
//! - Style cascade helpers: `defaults` at workload root,
//!   `defaults` at group level, then per-item directives.
//!
//! The crate is parser-only. Renderers in `nmbrs/src/plot_metrics.rs`
//! and the corresponding table renderer consume `ReportItem.body`
//! plus the resolved [`Style`] — they don't touch the raw YAML
//! again.

use serde::{Deserialize, Serialize};
use std::collections::HashSet;

pub mod vocab;
pub use vocab::{
    AGG_FNS, ALL_DIRECTIVES, AXIS_SCALES, Directive, DirectiveTarget, KindMask, LINE_STYLES,
    MARKER_SHAPES, PALETTE_NAMES, ValueProvider, YamlForm, cli_flags_for, directive_by_cli_flag,
    directive_by_yaml_keyword, directives_for,
};

/// Top-level `report:` block.
#[derive(Debug, Clone, Default, Serialize, Deserialize)]
pub struct Report {
    /// Cross-cutting style + metadata defaults declared via the
    /// reserved `defaults:` mapping. Cascade into every group.
    #[serde(default)]
    pub defaults: Style,
    /// Groups in YAML declaration order. Each group's name becomes
    /// a markdown section heading; items render in body order.
    #[serde(default)]
    pub groups: Vec<ReportGroup>,
}

impl Report {
    /// Iterate every item across every group in declaration order.
    pub fn items(&self) -> impl Iterator<Item = &ReportItem> {
        self.groups.iter().flat_map(|g| g.items.iter())
    }

    /// Find an item by canonical name. Returns the first match in
    /// declaration order. Names should be unique within a `Report`
    /// (collisions are caught at parse time).
    pub fn find(&self, name: &str) -> Option<&ReportItem> {
        self.items().find(|i| i.name == name)
    }

    /// Resolve the effective style for one item, walking the
    /// cascade: report defaults → group defaults → item directives.
    pub fn effective_style(&self, group: &ReportGroup, item: &ReportItem) -> Style {
        let mut s = self.defaults.clone();
        s.merge_from(&group.defaults);
        s.merge_from(&item.style);
        s
    }
}

/// One named container in `report:`. Holds zero or more items
/// plus group-level defaults.
#[derive(Debug, Clone, Default, Serialize, Deserialize)]
pub struct ReportGroup {
    /// YAML key the group was declared under (e.g.
    /// `recall_block`). Used as the markdown section heading.
    pub name: String,
    /// Group-level style defaults (from `defaults <directives>`
    /// lines at the start of the group body). Cascade into every
    /// item in this group.
    #[serde(default)]
    pub defaults: Style,
    /// Items declared in this group, in body declaration order.
    #[serde(default)]
    pub items: Vec<ReportItem>,
}

/// One renderable report item — either a plot or a table.
#[derive(Debug, Clone, Default, Serialize, Deserialize)]
pub struct ReportItem {
    /// `plot` or `table`.
    pub kind: Kind,
    /// Canonical name (the token after `plot` / `table`).
    pub name: String,
    /// Display label (`label "..."`). Falls back to a prettified
    /// form of `name` when absent.
    #[serde(default)]
    pub label: Option<String>,
    /// Output-filename stem (`as <stem>`). When absent, default
    /// is `plot_<name>` / `table_<name>` derived at render time.
    #[serde(default)]
    pub as_stem: Option<String>,
    /// Per-item style overrides parsed from the directive body.
    #[serde(default)]
    pub style: Style,
    /// Raw spec body — the directive lines following the
    /// `<kind> <name>` line, with `as`/`label`/style directives
    /// stripped out (they live on the [`ReportItem`] / [`Style`]
    /// fields). Renderers parse this exactly the way they parse
    /// the legacy CLI spec strings.
    #[serde(default)]
    pub body: String,
    /// Output file this item flows into when the markdown
    /// assembler runs. `None` ⇒ default `summary.md`. Set by a
    /// preceding `file <filename>` directive in the same group.
    /// Resolved at parse time so consumers don't need to walk
    /// the group order.
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub target_file: Option<String>,
    /// Declaration ordinal across the whole `report:` block,
    /// stamped by [`parse_report`] and persisted as an
    /// `order <n>` directive line, so a db-sourced render
    /// (`report.<name>` metadata rows, which iterate in key
    /// order) can restore declaration order. `serde(skip)`:
    /// positional metadata derived at parse, not document
    /// content.
    #[serde(skip)]
    pub order: Option<usize>,
    /// Plot-only directive: when `true`, the renderer
    /// emits a companion table immediately after the plot
    /// in the same markdown file, sharing the plot's
    /// underlying query data. The companion table reuses
    /// the plot's name with a `_table` suffix for its
    /// anchor and figure-numbering slot, so users can
    /// link to either view independently.
    ///
    /// Set via `with-table: true` in the plot's body.
    /// No-op for `Kind::Table` and other non-plot items.
    /// Default `false` — plots without an explicit toggle
    /// keep their existing single-image behaviour.
    #[serde(default, skip_serializing_if = "std::ops::Not::not")]
    pub with_table: bool,
    /// Plot-only directive: when non-empty, the renderer
    /// emits one companion table per distinct value tuple
    /// of the listed label keys. Each table is filtered to
    /// rows whose labels match that tuple, and gets its own
    /// markdown section / standalone file named with the
    /// tuple values appended.
    ///
    /// Set via `with-tables: [label1, label2, …]` in the
    /// plot body. Independent of (and composes with)
    /// `with-table: true` — the singular form still emits
    /// a single un-faceted table when set.
    #[serde(default, skip_serializing_if = "Vec::is_empty")]
    pub with_tables: Vec<String>,
}

/// Kind discriminator. Identifies which renderer owns the item.
///
/// `Plot` and `Table` are figures — they carry data and get a
/// figure number. `Text` is markdown prose; `File` is a scope
/// directive that switches subsequent items' output file.
/// `Details` is an auto-injected session-context block (the
/// runner emits one to every target markdown file at end-of-
/// run; users can also declare it explicitly to control its
/// position). Only Plot and Table participate in figure
/// numbering.
#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, Serialize, Deserialize)]
#[serde(rename_all = "lowercase")]
#[derive(Default)]
pub enum Kind {
    #[default]
    Plot,
    Table,
    Text,
    File,
    Details,
}

impl Kind {
    pub fn as_str(&self) -> &'static str {
        match self {
            Kind::Plot => "plot",
            Kind::Table => "table",
            Kind::Text => "text",
            Kind::File => "file",
            Kind::Details => "details",
        }
    }

    /// True for kinds that contribute a figure to the report
    /// (plot, table). Used by the figure-numbering pass.
    pub fn is_figure(&self) -> bool {
        matches!(self, Kind::Plot | Kind::Table)
    }
}

/// SRD-46 output destination for a rendered report item.
///
/// The set is declared with `to <dest>[, <dest>…]` and rides the
/// style cascade (report defaults → group defaults → item), so a
/// whole report can be routed in one line. An inner declaration
/// REPLACES an outer one rather than unioning with it — routing
/// you can't take back would make the outer default a trap.
#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
#[serde(rename_all = "lowercase")]
pub enum Destination {
    /// The session directory: standalone artifact + markdown
    /// upsert. The default when nothing is declared.
    SessionDir,
    /// The console form on stdout. Never implied — see
    /// [`vocab::DESTINATION_NAMES`].
    Stdout,
    /// The console form on stderr.
    Stderr,
    /// Render nothing.
    None,
}

impl Destination {
    /// Parse one destination name. `session` and `session_dir`
    /// are accepted spellings of `sessiondir` — the concept has
    /// three natural spellings and rejecting two of them buys
    /// nothing.
    pub fn parse(s: &str) -> Option<Self> {
        Some(match s.trim().to_ascii_lowercase().as_str() {
            "sessiondir" | "session" | "session_dir" => Self::SessionDir,
            "stdout" => Self::Stdout,
            "stderr" => Self::Stderr,
            "none" | "off" => Self::None,
            _ => return None,
        })
    }

    pub fn as_str(self) -> &'static str {
        match self {
            Self::SessionDir => "sessiondir",
            Self::Stdout => "stdout",
            Self::Stderr => "stderr",
            Self::None => "none",
        }
    }

    /// Parse a comma- (or whitespace-) separated destination
    /// list. `none` anywhere in the list wins outright: it is a
    /// suppression, not a peer.
    pub fn parse_list(s: &str) -> Result<Vec<Self>, String> {
        let mut out: Vec<Self> = Vec::new();
        for tok in s.split([',', ' ', '\t']).filter(|t| !t.trim().is_empty()) {
            let d = Self::parse(tok).ok_or_else(|| {
                format!(
                    "unknown destination '{}' — expected one of: {}",
                    tok.trim(),
                    vocab::DESTINATION_NAMES.join(", ")
                )
            })?;
            if d == Self::None {
                return Ok(vec![Self::None]);
            }
            if !out.contains(&d) {
                out.push(d);
            }
        }
        if out.is_empty() {
            return Err(format!(
                "`to` needs at least one destination — expected one of: {}",
                vocab::DESTINATION_NAMES.join(", ")
            ));
        }
        Ok(out)
    }
}

/// Style and figure-metadata bag. Every field optional; cascade
/// is "first non-`None` wins outer-to-inner".
#[derive(Debug, Clone, Default, Serialize, Deserialize)]
pub struct Style {
    /// Palette name or numeric index (`"wong"`, `"3"`).
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub palette: Option<String>,
    /// Line-dash style: `solid`, `dashed`, `dotted`, `dashdot`,
    /// `none`.
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub line: Option<String>,
    /// Stroke width in pixels.
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub width: Option<f32>,
    /// Marker shape: `none`, `circle`, `square`, `triangle`,
    /// `diamond`, `plus`, `cross`.
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub marker: Option<String>,
    /// Marker radius in pixels.
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub size: Option<f32>,
    /// Hex color override (`#RRGGBB`).
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub color: Option<String>,
    /// Figure width in pixels.
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub figure_width: Option<u32>,
    /// Figure height in pixels.
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub figure_height: Option<u32>,
    /// Per-series JSON sub-block overrides keyed by the
    /// `<key>=<value>` discriminator after the `series` directive.
    /// Values are arbitrary JSON objects; renderers consume the
    /// fields they recognise.
    #[serde(default, skip_serializing_if = "Vec::is_empty")]
    pub series: Vec<SeriesOverride>,
    /// SRD-46 output routing (`to stdout, sessiondir`). `None`
    /// means "not declared at this level" — the cascade keeps
    /// looking outward, and the render entry point supplies the
    /// default when nothing declared it anywhere.
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub destinations: Option<Vec<Destination>>,
}

/// One `series <key>=<value> {...}` directive.
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct SeriesOverride {
    /// Discriminator key (e.g. `profile`).
    pub key: String,
    /// Discriminator value (e.g. `hnsw`).
    pub value: String,
    /// Style overrides — strict JSON object verbatim, parsed
    /// into a Style at apply time.
    pub style: Style,
}

impl ReportItem {
    /// Render this item back to its canonical YAML directive
    /// form — the same string shape the workload-YAML parser
    /// in [`parse_group`] consumes. Round-trips:
    /// `parse_group(... item.to_yaml_directive_string() ...) == item`.
    ///
    /// The output is one or more lines:
    ///
    /// ```text
    /// plot <name>
    ///   as <stem>
    ///   label "<label>"
    ///   palette=<v>
    ///   line=<v> width=<n> marker=<v> size=<n> color=<#hex>
    ///   <body lines verbatim>
    ///   series <key>=<val> {<json>}
    /// ```
    ///
    /// Order matches [`vocab::ALL_DIRECTIVES`] so the
    /// round-trip is stable. Style fields that are `None` are
    /// omitted; the body is appended verbatim (it carries the
    /// renderer-consumed `over` / `by` / `where` / `agg` /
    /// `xlabel` / etc. lines).
    pub fn to_yaml_directive_string(&self) -> String {
        let mut out = String::new();
        // Header line: `<kind> <name>`. `Details` items also
        // round-trip; `File` directives use their target stem
        // as the "name" (a `file <stem>` line).
        out.push_str(self.kind.as_str());
        out.push(' ');
        out.push_str(&self.name);
        // Text headers need the trailing colon: it is the parser's
        // "named" signal (a bare `text <word>` line is the legacy
        // anonymous single-line body form). Without it the
        // round-trip anonymized the item and leaked the name into
        // the rendered prose.
        if matches!(self.kind, Kind::Text) {
            out.push(':');
        }
        out.push('\n');

        // `as <stem>` and `label "<text>"` come first when
        // present — the reader expects identity directives
        // before the per-renderer body.
        if let Some(stem) = &self.as_stem {
            out.push_str("  as ");
            out.push_str(stem);
            out.push('\n');
        }
        if let Some(label) = &self.label {
            out.push_str("  label \"");
            out.push_str(&label.replace('\\', "\\\\").replace('"', "\\\""));
            out.push_str("\"\n");
        }
        if let Some(target) = &self.target_file {
            out.push_str("  target ");
            out.push_str(target);
            out.push('\n');
        }
        // Routing travels with the item so a persisted item
        // replayed by `nmbrs report` lands where it was declared
        // to land, not where the replaying command defaults.
        if let Some(dests) = &self.style.destinations {
            out.push_str("  to ");
            out.push_str(
                &dests
                    .iter()
                    .map(|d| d.as_str())
                    .collect::<Vec<_>>()
                    .join(", "),
            );
            out.push('\n');
        }
        if let Some(order) = self.order {
            out.push_str("  order ");
            out.push_str(&order.to_string());
            out.push('\n');
        }
        if self.with_table {
            out.push_str("  with-table true\n");
        }
        if !self.with_tables.is_empty() {
            out.push_str("  with-tables [");
            out.push_str(&self.with_tables.join(", "));
            out.push_str("]\n");
        }

        // Style scalars in declaration order from the vocab
        // registry. Each is `<key>=<value>` on its own line —
        // matches the existing parser's `apply_one_style_kv`
        // contract.
        for line in self.style.scalar_directive_lines() {
            out.push_str("  ");
            out.push_str(&line);
            out.push('\n');
        }

        // Body lines (over / by / where / agg / xlabel / etc.)
        // are passed through verbatim. The body is already in
        // the canonical form the renderer expects.
        if !self.body.trim().is_empty() {
            for line in self.body.split('\n') {
                if line.trim().is_empty() {
                    continue;
                }
                out.push_str("  ");
                out.push_str(line.trim_start());
                out.push('\n');
            }
        }

        // Per-series sub-blocks. Use the brace-free directive
        // form (`series profile=hnsw line=dashed`) when only
        // simple key=value scalars are involved; fall back to
        // the JSON form for completeness when the series style
        // carries series-style fields that don't survive the
        // simple form (today they all do, but reserved for
        // future extension).
        for s in &self.style.series {
            out.push_str("  style ");
            out.push_str(&s.key);
            out.push('=');
            out.push_str(&s.value);
            for line in s.style.scalar_directive_lines() {
                out.push(' ');
                out.push_str(&line);
            }
            out.push('\n');
        }

        out
    }
}

impl Style {
    /// Render the scalar (non-series) fields of this style
    /// as a list of `key=value` directive lines, in the
    /// canonical [`vocab::ALL_DIRECTIVES`] order. Used by
    /// [`ReportItem::to_yaml_directive_string`] and by
    /// the `series` sub-block renderer.
    ///
    /// `None` fields are skipped; only fields whose vocab
    /// `target` is [`vocab::DirectiveTarget::StyleField`]
    /// are emitted.
    pub fn scalar_directive_lines(&self) -> Vec<String> {
        let mut out = Vec::new();
        for d in vocab::ALL_DIRECTIVES {
            if !matches!(d.target, vocab::DirectiveTarget::StyleField) {
                continue;
            }
            let value: Option<String> = match d.yaml_directive {
                "palette" => self.palette.clone(),
                "line" => self.line.clone(),
                "width" => self.width.map(|v| v.to_string()),
                "marker" => self.marker.clone(),
                "size" => self.size.map(|v| v.to_string()),
                "color" => self.color.clone(),
                "figure_width" => self.figure_width.map(|v| v.to_string()),
                "figure_height" => self.figure_height.map(|v| v.to_string()),
                _ => None,
            };
            if let Some(v) = value {
                out.push(format!("{}={}", d.yaml_directive, v));
            }
        }
        out
    }

    /// Merge `other` into `self`: every `Some(_)` field in `other`
    /// overrides the corresponding field in `self`. Used to walk
    /// the cascade outer → inner.
    pub fn merge_from(&mut self, other: &Style) {
        if other.palette.is_some() {
            self.palette = other.palette.clone();
        }
        if other.line.is_some() {
            self.line = other.line.clone();
        }
        if other.width.is_some() {
            self.width = other.width;
        }
        if other.marker.is_some() {
            self.marker = other.marker.clone();
        }
        if other.size.is_some() {
            self.size = other.size;
        }
        if other.color.is_some() {
            self.color = other.color.clone();
        }
        if other.figure_width.is_some() {
            self.figure_width = other.figure_width;
        }
        if other.figure_height.is_some() {
            self.figure_height = other.figure_height;
        }
        if !other.series.is_empty() {
            for s in &other.series {
                self.series
                    .retain(|t| !(t.key == s.key && t.value == s.value));
                self.series.push(s.clone());
            }
        }
        // Routing REPLACES rather than unions: an item declaring
        // `to stdout` means stdout, not "stdout on top of
        // whatever the group defaulted to".
        if other.destinations.is_some() {
            self.destinations = other.destinations.clone();
        }
    }

    /// The declared destination set, or `default_to` when no
    /// level of the cascade declared one. Callers pass the
    /// default their entry point implies — files-only for
    /// automatic end-of-run rendering, files+stdout for an
    /// explicit `nmbrs report` invocation.
    pub fn destinations_or(&self, default_to: &[Destination]) -> Vec<Destination> {
        match &self.destinations {
            Some(d) => d.clone(),
            None => default_to.to_vec(),
        }
    }
}

// ---------------------------------------------------------------------------
// Parsing
// ---------------------------------------------------------------------------

/// Reserved directive keywords. Used to:
/// (1) reject group child keys that collide with directive names
///     (warn / error in strict mode),
/// (2) detect when a directive line is the start of a new item
///     (`plot`, `table`) vs a continuation directive.
const STYLE_DIRECTIVE_KEYWORDS: &[&str] = &[
    "palette",
    "line",
    "width",
    "marker",
    "size",
    "color",
    "figure_width",
    "figure_height",
    "style",
    "label",
    "as",
    "to",
];

const ITEM_KIND_KEYWORDS: &[&str] = &["plot", "table", "text", "file"];

const ALL_RESERVED_DIRECTIVES: &[&str] = &[
    "defaults",
    "plot",
    "table",
    "text",
    "file",
    "palette",
    "line",
    "width",
    "marker",
    "size",
    "color",
    "figure_width",
    "figure_height",
    "style",
    "label",
    "as",
    "to",
];

/// Parse a `report:` value (a YAML mapping) into a [`Report`].
///
/// Errors describe the offending input precisely; warnings (e.g.
/// empty groups, kind-mismatched directives) are collected
/// alongside so callers can decide whether to surface or promote
/// to errors under strict mode.
pub fn parse_report(value: &serde_json::Value) -> Result<ParsedReport, String> {
    let map = value
        .as_object()
        .ok_or_else(|| "report: must be a mapping".to_string())?;

    let mut report = Report::default();
    let mut warnings: Vec<String> = Vec::new();
    let mut seen_names: HashSet<String> = HashSet::new();
    // Global counter for anonymous text item naming so the
    // round-trip identity (`report.<name>` keys) stays unique
    // across the whole document, not just within one group.
    let mut text_counter: usize = 0;

    for (key, v) in map {
        let key: &str = key.as_str();
        if key == "defaults" {
            report.defaults =
                parse_style_mapping(v).map_err(|e| format!("report.defaults: {e}"))?;
            continue;
        }
        if STYLE_DIRECTIVE_KEYWORDS.contains(&key) {
            warnings.push(format!(
                "report.{key}: bare directive keyword used as a group name; \
                 nest under `defaults:` to set as a default, or rename the group"
            ));
        }

        let body = match v {
            serde_json::Value::String(s) => s.clone(),
            serde_json::Value::Null => String::new(),
            _ => {
                return Err(format!(
                    "report.{key}: must be a string (single-line or block scalar) \
                 of directive lines starting with `plot` / `table`"
                ));
            }
        };

        let group = parse_group(key, &body, &mut warnings, &mut text_counter)?;
        for it in &group.items {
            if !seen_names.insert(it.name.clone()) {
                return Err(format!(
                    "duplicate report item name '{}' (within scope: workload root)",
                    it.name
                ));
            }
        }
        if group.items.is_empty() {
            warnings.push(format!(
                "report.{key}: empty group (no `plot` or `table` items)"
            ));
        }
        report.groups.push(group);
    }

    // Stamp the declaration ordinal across the whole block. The
    // persisted form (`order <n>`) carries it through the db so
    // `nmbrs report` renders items in declaration order even when
    // the metadata rows iterate alphabetically by key.
    let mut ordinal: usize = 0;
    for group in &mut report.groups {
        for item in &mut group.items {
            item.order = Some(ordinal);
            ordinal += 1;
        }
    }

    Ok(ParsedReport { report, warnings })
}

/// Result of parsing a `report:` block. Warnings are non-fatal
/// in normal mode; callers running under SRD-15 strict mode
/// should promote them to errors.
#[derive(Debug, Clone, Default)]
pub struct ParsedReport {
    pub report: Report,
    pub warnings: Vec<String>,
}

/// Parse a single persisted-form report item — header line
/// (`<kind> <name>`) followed by indented directive lines, as
/// produced by [`ReportItem::to_yaml_directive_string`]. Used by
/// the session-db fallback path in `nmbrs report` so the
/// directive-form knowledge lives in one place.
pub fn parse_persisted_item(body: &str) -> Result<ReportItem, String> {
    let mut warnings: Vec<String> = Vec::new();
    let mut text_counter: usize = 0;
    let group = parse_group("__persisted__", body, &mut warnings, &mut text_counter)?;
    group
        .items
        .into_iter()
        .next()
        .ok_or_else(|| "persisted report item body did not yield any item".to_string())
}

fn parse_group(
    name: &str,
    body: &str,
    warnings: &mut Vec<String>,
    text_counter: &mut usize,
) -> Result<ReportGroup, String> {
    let mut group = ReportGroup {
        name: name.to_string(),
        ..Default::default()
    };
    let mut current: Option<PartialItem> = None;
    // Active output file scope (set by a `file <filename>` line).
    // Items declared after a `file` directive inherit this until
    // the next `file` directive in the same group.
    let mut current_file: Option<String> = None;

    let emit = |partial: PartialItem,
                target_file: &Option<String>,
                group: &mut ReportGroup,
                warnings: &mut Vec<String>|
     -> Result<(), String> {
        let mut item = partial.finalize(warnings)?;
        if item.target_file.is_none() {
            item.target_file = target_file.clone();
        }
        group.items.push(item);
        Ok(())
    };

    for (lineno, raw_line) in body.lines().enumerate() {
        // Strip `#` line comments (SRD-46) before parsing —
        // honours quoted strings so `label "see #1 above"`
        // survives.
        let stripped = strip_line_comment(raw_line);
        let line = stripped.trim();
        if line.is_empty() {
            continue;
        }
        let line_no = lineno + 1;

        // `defaults <directives>` — group-level defaults. Only
        // valid before any item starts (since otherwise the
        // intent is ambiguous: do they apply to subsequent items
        // only? to all items? we pick "before-first-item" so
        // there's exactly one place defaults can land).
        if let Some(rest) = strip_directive_keyword(line, "defaults") {
            if current.is_some() {
                return Err(format!(
                    "report.{name}:{line_no}: `defaults` must precede the first \
                     item in the group"
                ));
            }
            apply_directives_to_style(rest, &mut group.defaults, name, line_no)?;
            continue;
        }

        // `<kind> <args>` — start of new item.
        if let Some((kind, rest)) = strip_kind_keyword(line) {
            if let Some(prev) = current.take() {
                emit(prev, &current_file, &mut group, warnings)?;
            }
            match kind {
                Kind::Plot | Kind::Table => {
                    let mut tokens = rest.splitn(2, char::is_whitespace);
                    let raw_item_name =
                        tokens.next().filter(|s| !s.is_empty()).ok_or_else(|| {
                            format!(
                                "report.{name}:{line_no}: `{}` must be followed by a name",
                                kind.as_str()
                            )
                        })?;
                    // Allow trailing `:` on the block header
                    // (`plot recall_vs_qps:`) for visual parity with
                    // the body's `name: value` directives. The
                    // colon is a delimiter — strip it before the
                    // reserved-keyword check so `plot text:` still
                    // sees the name as `text`.
                    let item_name = raw_item_name.strip_suffix(':').unwrap_or(raw_item_name);
                    if item_name.is_empty() {
                        return Err(format!(
                            "report.{name}:{line_no}: `{}` must be followed by a name",
                            kind.as_str()
                        ));
                    }
                    if ALL_RESERVED_DIRECTIVES.contains(&item_name) {
                        return Err(format!(
                            "report.{name}:{line_no}: item name '{item_name}' \
                             collides with a reserved directive keyword"
                        ));
                    }
                    let trailing = tokens.next().unwrap_or("");
                    let mut p = PartialItem::new(kind, item_name, name.to_string(), line_no);
                    if !trailing.trim().is_empty() {
                        p.directives.push(trailing.to_string());
                    }
                    current = Some(p);
                }
                Kind::Text => {
                    // Three surface forms for a `text` block:
                    //   text <body>                              — anonymous, body on this line
                    //   text <name>[:]                           — named, body on continuation lines
                    //   text <name> as "<label>"[:]              — named + alias for the markdown heading
                    //
                    // The trailing `:` (per the new uniform
                    // `name: value` style) is decorative and
                    // gets stripped before the name is captured.
                    // A bare `text` with no first token degrades
                    // to the anonymous auto-name form, preserving
                    // the legacy single-line shape.
                    let rest = rest.trim();
                    // Strip the trailing block-header colon from
                    // the WHOLE line before tokenising, so it
                    // doesn't get sucked into the `as "..."`
                    // alias as `"...":`.
                    let body = rest.strip_suffix(':').unwrap_or(rest).trim_end();
                    let header_has_colon = body.len() < rest.len();
                    let mut tokens = body.splitn(2, char::is_whitespace);
                    let first = tokens.next().unwrap_or("").trim();
                    let after = tokens.next().unwrap_or("").trim();
                    // Decide between named and anonymous. A `text`
                    // block is named only when the author opted in
                    // with a positive signal:
                    //   - a trailing `:` on the header line, or
                    //   - an `as "<label>"` clause.
                    // A bare `text <word>` line stays anonymous —
                    // it's the legacy "single-line text body"
                    // shape (preserves `text First` / `text Second`
                    // auto-numbering tests + workloads in the wild).
                    let has_as_alias = strip_directive_keyword(after, "as").is_some();
                    let looks_named = !first.is_empty()
                        && is_bare_text_name(first)
                        && (header_has_colon || has_as_alias);
                    let (item_name, alias) = if looks_named {
                        let alias = strip_directive_keyword(after, "as").map(parse_quoted_or_bare);
                        (first.to_string(), alias)
                    } else {
                        // Anonymous — auto-name globally so the
                        // persistence round-trip keeps unique
                        // `report.<name>` keys.
                        *text_counter += 1;
                        let auto = format!("text_{:03}", *text_counter);
                        (auto, None)
                    };
                    let mut p = PartialItem::new(Kind::Text, &item_name, name.to_string(), line_no);
                    if let Some(label) = alias {
                        p.directives.push(format!("label {label}"));
                    } else if !looks_named && !rest.is_empty() {
                        // Anonymous: keep the original-line body
                        // as a directive (legacy shape).
                        p.directives.push(rest.to_string());
                    }
                    current = Some(p);
                }
                Kind::File => {
                    // `file <filename> [as <label>]` — switches
                    // the active output file. The directive is
                    // also persisted as a Kind::File item so the
                    // listing surface can show it; no body
                    // attaches.
                    let mut tokens = rest.splitn(2, char::is_whitespace);
                    let filename = tokens
                        .next()
                        .filter(|s| !s.is_empty())
                        .ok_or_else(|| {
                            format!(
                                "report.{name}:{line_no}: `file` must be followed by a filename"
                            )
                        })?
                        .to_string();
                    let trailing = tokens.next().unwrap_or("");
                    let mut p = PartialItem::new(Kind::File, &filename, name.to_string(), line_no);
                    // Honor optional `as '<label>'` on the same
                    // line (passed through to finalize via the
                    // directive list — the `label` extractor
                    // already understands quoted strings).
                    if !trailing.trim().is_empty() {
                        // Translate `as 'X'` → `label X` so the
                        // existing label extractor handles it.
                        let trailing = trailing.trim();
                        if let Some(rest) = strip_directive_keyword(trailing, "as") {
                            p.directives.push(format!("label {rest}"));
                        } else {
                            p.directives.push(trailing.to_string());
                        }
                    }
                    current_file = Some(filename);
                    current = Some(p);
                }
                Kind::Details => {
                    // Auto-injected at end-of-run; explicit
                    // `details` declarations are accepted so the
                    // author can pin position. Body is whatever
                    // the assembler decides — usually empty
                    // when declared explicitly (the runtime
                    // fills it in).
                    let mut p =
                        PartialItem::new(Kind::Details, "details", name.to_string(), line_no);
                    if !rest.trim().is_empty() {
                        p.directives.push(rest.to_string());
                    }
                    current = Some(p);
                }
            }
            continue;
        }

        // Continuation directive line for the current item.
        match current.as_mut() {
            Some(p) => p.directives.push(line.to_string()),
            None => {
                return Err(format!(
                    "report.{name}:{line_no}: directive `{line}` precedes any \
                 kind keyword (plot / table / text / file)"
                ));
            }
        }
    }

    if let Some(p) = current.take() {
        emit(p, &current_file, &mut group, warnings)?;
    }
    Ok(group)
}

struct PartialItem {
    kind: Kind,
    name: String,
    group: String,
    line_no: usize,
    directives: Vec<String>,
}

impl PartialItem {
    fn new(kind: Kind, name: &str, group: String, line_no: usize) -> Self {
        Self {
            kind,
            name: name.to_string(),
            group,
            line_no,
            directives: Vec::new(),
        }
    }

    /// Pull `label` / `as` / style directives out of the directive
    /// body. Anything else is left in `body` for the kind-specific
    /// renderer to consume.
    fn finalize(self, warnings: &mut Vec<String>) -> Result<ReportItem, String> {
        let mut item = ReportItem {
            kind: self.kind,
            name: self.name.clone(),
            label: None,
            as_stem: None,
            style: Style::default(),
            body: String::new(),
            target_file: None,
            order: None,
            with_table: false,
            with_tables: Vec::new(),
        };

        // Text items: body is verbatim markdown. Pull out a
        // leading `label "..."` line if present (so the heading
        // can carry a title) plus the identity directives the
        // persisted round-trip emits — `target <file>` (only when
        // the remainder is a single token, so prose that happens
        // to start with the word stays prose) and `order <n>`
        // (only when the remainder is a number). Every other
        // line stays as prose. Style / series / `as` directives
        // don't apply to text — preserved in body if the user
        // wrote them (most likely they meant prose).
        if matches!(self.kind, Kind::Text) {
            let mut body_lines: Vec<String> = Vec::new();
            for line in &self.directives {
                let trimmed = line.trim();
                if trimmed.is_empty() {
                    body_lines.push(String::new());
                    continue;
                }
                if let Some(rest) = strip_directive_keyword(trimmed, "label") {
                    item.label = Some(parse_quoted_or_bare(rest));
                    continue;
                }
                if let Some(rest) = strip_directive_keyword(trimmed, "to") {
                    item.style.destinations = Some(
                        Destination::parse_list(rest)
                            .map_err(|e| format!("text '{}': {e}", self.name))?,
                    );
                    continue;
                }
                if let Some(rest) = strip_directive_keyword(trimmed, "target") {
                    let rest = rest.trim();
                    if !rest.is_empty() && !rest.contains(char::is_whitespace) {
                        item.target_file = Some(rest.to_string());
                        continue;
                    }
                }
                if let Some(rest) = strip_directive_keyword(trimmed, "order") {
                    if let Ok(n) = rest.trim().parse::<usize>() {
                        item.order = Some(n);
                        continue;
                    }
                }
                body_lines.push(line.clone());
            }
            item.body = body_lines.join("\n");
            return Ok(item);
        }

        let mut residual: Vec<String> = Vec::new();
        for line in &self.directives {
            let line = line.trim();
            if line.is_empty() {
                continue;
            }

            if let Some(rest) = strip_directive_keyword(line, "label") {
                item.label = Some(parse_quoted_or_bare(rest));
                continue;
            }
            if let Some(rest) = strip_directive_keyword(line, "to") {
                item.style.destinations = Some(
                    Destination::parse_list(rest)
                        .map_err(|e| format!("{} '{}': {e}", self.kind.as_str(), self.name))?,
                );
                continue;
            }
            if let Some(rest) = strip_directive_keyword(line, "as") {
                item.as_stem = Some(rest.trim().to_string());
                continue;
            }
            // `target <filename>` — per-item override that pins
            // the output markdown file independently of any
            // surrounding `file <filename>` scope. Used by the
            // persisted form (runner emits it for every item so
            // the round-trip through the db preserves the
            // target the workload's `file` scope assigned).
            if let Some(rest) = strip_directive_keyword(line, "target") {
                item.target_file = Some(rest.trim().to_string());
                continue;
            }
            // `order <n>` — declaration ordinal, emitted by the
            // persisted form so db-sourced renders keep the
            // workload's declaration order.
            if let Some(rest) = strip_directive_keyword(line, "order") {
                if let Ok(n) = rest.trim().parse::<usize>() {
                    item.order = Some(n);
                    continue;
                }
            }
            // `with-tables: [label1, label2, …]` — plot-only
            // multi-table fan-out. Emits one companion
            // table per distinct value tuple of the listed
            // labels. Comes before `with-table` matching so
            // the plural form isn't shadowed by the
            // prefix-trimmed singular.
            if let Some(rest) = strip_directive_keyword(line, "with-tables") {
                let trimmed = rest.trim().trim_matches(':').trim();
                let inner = trimmed.strip_prefix('[')
                    .and_then(|s| s.strip_suffix(']'))
                    .ok_or_else(|| format!(
                        "report.{}:{} `with-tables`: expected `[label1, label2, …]`, got `{trimmed}`",
                        self.group, self.line_no,
                    ))?;
                let labels: Vec<String> = inner
                    .split(',')
                    .map(|s| s.trim().trim_matches('"').trim_matches('\'').to_string())
                    .filter(|s| !s.is_empty())
                    .collect();
                if labels.is_empty() {
                    return Err(format!(
                        "report.{}:{} `with-tables`: list is empty — drop the directive \
                         or list one or more label keys",
                        self.group, self.line_no,
                    ));
                }
                if !matches!(self.kind, Kind::Plot) {
                    warnings.push(format!(
                        "report.{}:{} item '{}' uses `with-tables` but is a {}; \
                         only plots can have a faceted companion table.",
                        self.group,
                        self.line_no,
                        item.name,
                        item.kind.as_str(),
                    ));
                } else {
                    item.with_tables = labels;
                }
                continue;
            }
            // `with-table: true|false` — plot-only flag
            // that asks the renderer to emit a companion
            // table immediately after the plot, sharing
            // the plot's underlying query data. SRD-46
            // §"Table-from-plot". Accepted-but-warned for
            // non-plot items.
            if let Some(rest) = strip_directive_keyword(line, "with-table") {
                let v = rest.trim().trim_matches(':').trim();
                let truthy = matches!(
                    v.to_ascii_lowercase().as_str(),
                    "true" | "yes" | "on" | "1" | "",
                );
                let falsy = matches!(
                    v.to_ascii_lowercase().as_str(),
                    "false" | "no" | "off" | "0",
                );
                if !truthy && !falsy {
                    return Err(format!(
                        "report.{}:{} `with-table`: expected true/false, got '{v}'",
                        self.group, self.line_no,
                    ));
                }
                item.with_table = truthy;
                if item.with_table && !matches!(self.kind, Kind::Plot) {
                    warnings.push(format!(
                        "report.{}:{} item '{}' uses `with-table` but is a {}; \
                         only plots can have a companion table.",
                        self.group,
                        self.line_no,
                        item.name,
                        item.kind.as_str(),
                    ));
                    item.with_table = false;
                }
                continue;
            }
            if let Some(rest) = strip_directive_keyword(line, "style") {
                let so = parse_series_override(rest).map_err(|e| {
                    format!("report.{}:{} `style`: {}", self.group, self.line_no, e,)
                })?;
                item.style.series.push(so);
                continue;
            }

            if let Some(applied) = try_apply_style_directives(line, &mut item.style)? {
                if !applied {
                    residual.push(line.to_string());
                } else {
                    // Per-item directive that doesn't apply to the
                    // item's kind: warn (SRD-46 strict-mode hook).
                    if !style_directive_applies_to_kind(line, item.kind) {
                        warnings.push(format!(
                            "report.{}:{} item '{}' is a {} but uses \
                             directive `{}`, which has no effect on this kind",
                            self.group,
                            self.line_no,
                            item.name,
                            item.kind.as_str(),
                            line
                        ));
                    }
                }
                continue;
            }

            residual.push(line.to_string());
        }
        item.body = residual.join("\n");
        Ok(item)
    }
}

fn strip_directive_keyword<'a>(line: &'a str, kw: &str) -> Option<&'a str> {
    let line = line.trim_start();
    if let Some(rest) = line.strip_prefix(kw) {
        let next = rest.chars().next();
        if next.is_none()
            || next == Some(' ')
            || next == Some('\t')
            || next == Some('=')
            || next == Some(':')
        {
            return Some(
                rest.trim_start_matches(|c: char| c == ' ' || c == '\t' || c == '=' || c == ':'),
            );
        }
    }
    None
}

fn strip_kind_keyword(line: &str) -> Option<(Kind, &str)> {
    for kw in ITEM_KIND_KEYWORDS {
        if let Some(rest) = line.strip_prefix(kw)
            && let Some(next) = rest.chars().next()
            && next.is_whitespace()
        {
            let kind = match *kw {
                "plot" => Kind::Plot,
                "table" => Kind::Table,
                "text" => Kind::Text,
                "file" => Kind::File,
                _ => unreachable!(),
            };
            return Some((kind, rest.trim_start()));
        }
    }
    None
}

/// `true` when `s` is a bare identifier-shaped token suitable to
/// use as the name of a `text <name>` block — `[A-Za-z_][A-Za-z0-9_-]*`.
/// Falls back to anonymous-text auto-naming when the first token
/// has whitespace, punctuation, or starts with a digit; that's
/// the legacy single-line `text <body>` shape.
fn is_bare_text_name(s: &str) -> bool {
    let mut chars = s.chars();
    match chars.next() {
        Some(c) if c.is_ascii_alphabetic() || c == '_' => {}
        _ => return false,
    }
    chars.all(|c| c.is_ascii_alphanumeric() || c == '_' || c == '-')
}

fn parse_quoted_or_bare(s: &str) -> String {
    let s = s.trim();
    if let Some(stripped) = s.strip_prefix('"').and_then(|x| x.strip_suffix('"')) {
        return stripped.to_string();
    }
    if let Some(stripped) = s.strip_prefix('\'').and_then(|x| x.strip_suffix('\'')) {
        return stripped.to_string();
    }
    s.to_string()
}

/// Apply style directives from a single line (any combination
/// of `key=value` pairs separated by whitespace or commas) to
/// the given Style. Returns `Ok(Some(true))` if every token on
/// the line was a recognized style directive, `Ok(Some(false))`
/// if some tokens belonged to the kind-specific spec body, or
/// `Ok(None)` if the line doesn't look like a style directive
/// line at all (no `=` and no leading style keyword).
fn try_apply_style_directives(line: &str, style: &mut Style) -> Result<Option<bool>, String> {
    if !line.contains('=') && !line_starts_with_any(line, STYLE_DIRECTIVE_KEYWORDS) {
        return Ok(None);
    }
    let mut all_consumed = true;
    for token in tokenize_directive_line(line) {
        if let Some((k, v)) = token.split_once('=') {
            if STYLE_DIRECTIVE_KEYWORDS.contains(&k) {
                apply_one_style_kv(k, v, style)?;
            } else {
                all_consumed = false;
            }
        } else if STYLE_DIRECTIVE_KEYWORDS.contains(&token.as_str()) {
            // Bare keyword without value — not yet meaningful.
            return Err(format!("style directive `{token}` requires a value"));
        } else {
            all_consumed = false;
        }
    }
    Ok(Some(all_consumed))
}

fn apply_one_style_kv(k: &str, v: &str, style: &mut Style) -> Result<(), String> {
    let v = v.trim().trim_matches('"').trim_matches('\'');
    match k {
        "palette" => style.palette = Some(v.to_string()),
        "line" => style.line = Some(v.to_string()),
        "width" => {
            style.width = Some(
                v.parse()
                    .map_err(|_| format!("`width={v}` is not a number"))?,
            )
        }
        "marker" => style.marker = Some(v.to_string()),
        "size" => {
            style.size = Some(
                v.parse()
                    .map_err(|_| format!("`size={v}` is not a number"))?,
            )
        }
        "color" => style.color = Some(v.to_string()),
        "figure_width" => {
            style.figure_width = Some(
                v.parse()
                    .map_err(|_| format!("`figure_width={v}` is not an integer"))?,
            )
        }
        "figure_height" => {
            style.figure_height = Some(
                v.parse()
                    .map_err(|_| format!("`figure_height={v}` is not an integer"))?,
            )
        }
        // Routing, not cosmetics — but it cascades through the
        // same `defaults:` mapping, so it is applied here.
        "to" => style.destinations = Some(Destination::parse_list(v)?),
        _ => return Err(format!("unknown style directive `{k}`")),
    }
    Ok(())
}

fn tokenize_directive_line(line: &str) -> Vec<String> {
    // Split on whitespace and commas at depth 0. Quoted values
    // stay together. No JSON braces here — those are only inside
    // `series` sub-blocks and parsed separately.
    let mut out: Vec<String> = Vec::new();
    let mut cur = String::new();
    let mut quote: Option<char> = None;
    for ch in line.chars() {
        match quote {
            Some(q) if ch == q => {
                quote = None;
                cur.push(ch);
            }
            Some(_) => cur.push(ch),
            None => match ch {
                '"' | '\'' => {
                    quote = Some(ch);
                    cur.push(ch);
                }
                ' ' | '\t' | ',' => {
                    if !cur.is_empty() {
                        out.push(std::mem::take(&mut cur));
                    }
                }
                _ => cur.push(ch),
            },
        }
    }
    if !cur.is_empty() {
        out.push(cur);
    }
    out
}

fn line_starts_with_any(line: &str, kws: &[&str]) -> bool {
    let trimmed = line.trim_start();
    kws.iter().any(|kw| {
        trimmed.starts_with(kw)
            && trimmed
                .as_bytes()
                .get(kw.len())
                .is_none_or(|c| matches!(*c, b' ' | b'\t' | b'='))
    })
}

fn style_directive_applies_to_kind(line: &str, kind: Kind) -> bool {
    let head = tokenize_directive_line(line)
        .first()
        .map(|s| {
            s.split_once('=')
                .map(|(k, _)| k.to_string())
                .unwrap_or_else(|| s.clone())
        })
        .unwrap_or_default();
    !matches!(
        (kind, head.as_str()),
        (Kind::Table, "line" | "width" | "marker" | "size")
    )
}

fn parse_series_override(s: &str) -> Result<SeriesOverride, String> {
    // Shape: `<key>=<value> {<json>}`, `<key>=<value> <directives>`,
    // or the colon-separator form `<key>=<value>:<directives>` (same
    // shape the plot DSL's --style flag accepts; lets workload
    // authors write `style phase=pvs_query:line=dotted` without
    // having to remember which directive uses which separator).
    let s = s.trim();
    // Try `:` first when it appears before any whitespace — that's
    // the colon-form. Otherwise the head ends at the first
    // whitespace boundary as before.
    let first_colon = s.find(':');
    let first_ws = s.find(char::is_whitespace);
    let split_at = match (first_colon, first_ws) {
        (Some(c), Some(w)) if c < w => Some((c, 1)), // colon wins
        (Some(c), None) => Some((c, 1)),
        (_, Some(w)) => Some((w, 1)),
        (None, None) => None,
    };
    let (head, rest) = match split_at {
        Some((idx, n)) => (&s[..idx], s[idx + n..].trim_start()),
        None => (s, ""),
    };
    let (key, value) = head
        .split_once('=')
        .ok_or_else(|| format!("series discriminator must be <key>=<value>, got `{head}`"))?;

    let mut style = Style::default();
    let rest = rest.trim();

    if rest.starts_with('{') {
        // JSON sub-block — strict.
        if !rest.ends_with('}') {
            return Err("JSON sub-block must close with `}` on the same line".to_string());
        }
        let json: serde_json::Value =
            serde_json::from_str(rest).map_err(|e| format!("JSON sub-block parse error: {e}"))?;
        apply_json_to_style(&json, &mut style)?;
    } else if !rest.is_empty() {
        // Brace-free directive form.
        try_apply_style_directives(rest, &mut style)?;
    }

    Ok(SeriesOverride {
        key: key.trim().to_string(),
        value: value
            .trim()
            .trim_matches('"')
            .trim_matches('\'')
            .to_string(),
        style,
    })
}

fn apply_json_to_style(v: &serde_json::Value, style: &mut Style) -> Result<(), String> {
    let map = v
        .as_object()
        .ok_or_else(|| "series JSON sub-block must be an object".to_string())?;
    for (k, val) in map {
        let v_str = match val {
            serde_json::Value::String(s) => s.clone(),
            serde_json::Value::Number(n) => n.to_string(),
            serde_json::Value::Bool(b) => b.to_string(),
            _ => {
                return Err(format!(
                    "series JSON sub-block: value for `{k}` must be a string, number, or bool"
                ));
            }
        };
        apply_one_style_kv(k, &v_str, style)?;
    }
    Ok(())
}

fn apply_directives_to_style(
    line: &str,
    style: &mut Style,
    group: &str,
    line_no: usize,
) -> Result<(), String> {
    match try_apply_style_directives(line, style) {
        Ok(_) => Ok(()),
        Err(e) => Err(format!("report.{group}:{line_no}: {e}")),
    }
}

/// Strip a `#` line comment from one source line. A `#` starts
/// a comment only when it is at line start or preceded by
/// whitespace — so hex colors (`#117733`) and JSON sub-blocks
/// (`{"color": "#fff"}`) are unaffected. Quoted strings are
/// honoured so `label "see #1 above"` keeps its `#`.
fn strip_line_comment(line: &str) -> &str {
    let mut quote: Option<char> = None;
    let mut prev_ws = true; // start-of-line counts as whitespace boundary
    for (i, ch) in line.char_indices() {
        match quote {
            Some(q) if ch == q => {
                quote = None;
                prev_ws = false;
            }
            Some(_) => {
                prev_ws = false;
            }
            None => match ch {
                '"' | '\'' => {
                    quote = Some(ch);
                    prev_ws = false;
                }
                '#' if prev_ws => return &line[..i],
                c if c.is_whitespace() => {
                    prev_ws = true;
                }
                _ => {
                    prev_ws = false;
                }
            },
        }
    }
    line
}

fn parse_style_mapping(v: &serde_json::Value) -> Result<Style, String> {
    let map = v
        .as_object()
        .ok_or_else(|| "must be a mapping of style directives".to_string())?;
    let mut style = Style::default();
    for (key, val) in map {
        let key = key.as_str();
        let value: String = match val {
            serde_json::Value::String(s) => s.clone(),
            serde_json::Value::Number(n) => n.to_string(),
            serde_json::Value::Bool(b) => b.to_string(),
            serde_json::Value::Null => continue,
            _ => {
                return Err(format!(
                    "value for `{key}` must be a scalar (string, number, or bool)"
                ));
            }
        };
        apply_one_style_kv(key, &value, &mut style)?;
    }
    Ok(style)
}

#[cfg(test)]
mod tests {
    use super::*;

    fn parse(yaml: &str) -> ParsedReport {
        let v: serde_json::Value = serde_yaml::from_str(yaml).unwrap();
        parse_report(&v).unwrap()
    }

    #[test]
    fn single_plot_minimal() {
        let p = parse(
            r#"
recall_block: |
  plot recall_at_k10
    over limit by profile
    label "Recall@10 vs k limit"
"#,
        );
        assert_eq!(p.report.groups.len(), 1);
        let g = &p.report.groups[0];
        assert_eq!(g.name, "recall_block");
        assert_eq!(g.items.len(), 1);
        let item = &g.items[0];
        assert_eq!(item.kind, Kind::Plot);
        assert_eq!(item.name, "recall_at_k10");
        assert_eq!(item.label.as_deref(), Some("Recall@10 vs k limit"));
        assert!(item.body.contains("over limit"));
    }

    #[test]
    fn defaults_at_root_and_group() {
        let p = parse(
            r#"
defaults:
  palette: wong
  width: 1024

recall_block: |
  defaults palette=tol_muted
  plot recall_at_k10 over limit
"#,
        );
        assert_eq!(p.report.defaults.palette.as_deref(), Some("wong"));
        assert_eq!(p.report.defaults.width, Some(1024.0));
        let g = &p.report.groups[0];
        assert_eq!(g.defaults.palette.as_deref(), Some("tol_muted"));
        // Item-level inherits via merge_from at apply time.
        let s = p.report.effective_style(g, &g.items[0]);
        assert_eq!(s.palette.as_deref(), Some("tol_muted"));
        assert_eq!(s.width, Some(1024.0));
    }

    #[test]
    fn plots_and_tables_in_one_group() {
        let p = parse(
            r#"
combo: |
  plot recall_at_k10 over limit
  table recall_summary metric=recall@.* group_by=profile
"#,
        );
        let items = &p.report.groups[0].items;
        assert_eq!(items.len(), 2);
        assert_eq!(items[0].kind, Kind::Plot);
        assert_eq!(items[0].name, "recall_at_k10");
        assert_eq!(items[1].kind, Kind::Table);
        assert_eq!(items[1].name, "recall_summary");
    }

    #[test]
    fn style_json_sub_block() {
        let p = parse(
            r#"
g: |
  plot p1 over x
    style profile=hnsw {"line": "dashed", "marker": "triangle"}
"#,
        );
        let item = &p.report.groups[0].items[0];
        assert_eq!(item.style.series.len(), 1);
        let so = &item.style.series[0];
        assert_eq!(so.key, "profile");
        assert_eq!(so.value, "hnsw");
        assert_eq!(so.style.line.as_deref(), Some("dashed"));
        assert_eq!(so.style.marker.as_deref(), Some("triangle"));
    }

    #[test]
    fn style_directive_form() {
        let p = parse(
            r#"
g: |
  plot p1 over x
    style profile=ivf line=dotted color=#117733
"#,
        );
        let so = &p.report.groups[0].items[0].style.series[0];
        assert_eq!(so.value, "ivf");
        assert_eq!(so.style.line.as_deref(), Some("dotted"));
        assert_eq!(so.style.color.as_deref(), Some("#117733"));
    }

    #[test]
    fn duplicate_name_is_error() {
        let v: serde_json::Value = serde_yaml::from_str(
            r#"
g1: "plot dup over x"
g2: "plot dup over y"
"#,
        )
        .unwrap();
        assert!(parse_report(&v).is_err());
    }

    #[test]
    fn empty_group_warns() {
        let p = parse(
            r#"
empty_block: ""
"#,
        );
        assert_eq!(p.report.groups.len(), 1);
        assert!(p.warnings.iter().any(|w| w.contains("empty_block")));
    }

    #[test]
    fn persisted_text_item_round_trips_name_target_and_order() {
        // The full text-identity round trip: named text with a
        // heading label, a file target, and a declaration
        // ordinal must come back from the persisted form with
        // NOTHING leaked into the prose body. (Before this, the
        // header lost its named signal — the name and `target`
        // line rendered as prose and the section fell back to
        // summary.md.)
        let item = ReportItem {
            kind: Kind::Text,
            name: "key_metrics_overview".to_string(),
            label: Some("Overview".to_string()),
            target_file: Some("key_metrics.md".to_string()),
            order: Some(3),
            body: "First prose line.\ntarget audience is prose, not a directive.".to_string(),
            ..Default::default()
        };
        let persisted = item.to_yaml_directive_string();
        let back = parse_persisted_item(&persisted).expect("round-trip parse");
        assert_eq!(back.kind, Kind::Text);
        assert_eq!(back.name, "key_metrics_overview");
        assert_eq!(back.label.as_deref(), Some("Overview"));
        assert_eq!(back.target_file.as_deref(), Some("key_metrics.md"));
        assert_eq!(back.order, Some(3));
        // Prose survives verbatim — including a line that merely
        // STARTS with the word `target` (multi-token ⇒ prose).
        assert_eq!(back.body, item.body);
    }

    #[test]
    fn destination_list_parses_spellings_and_rejects_junk() {
        use Destination::*;
        assert_eq!(Destination::parse_list("stdout").unwrap(), vec![Stdout]);
        // Comma, whitespace, and mixed separators all work; the
        // three spellings of the session dir are one destination.
        assert_eq!(
            Destination::parse_list("stdout, sessiondir").unwrap(),
            vec![Stdout, SessionDir]
        );
        assert_eq!(
            Destination::parse_list("session_dir stderr").unwrap(),
            vec![SessionDir, Stderr]
        );
        assert_eq!(
            Destination::parse_list("session").unwrap(),
            vec![SessionDir]
        );
        // Duplicates collapse rather than double-delivering.
        assert_eq!(
            Destination::parse_list("stdout,stdout").unwrap(),
            vec![Stdout]
        );
        // `none` is a suppression, not a peer — it wins outright.
        assert_eq!(
            Destination::parse_list("stdout, none, sessiondir").unwrap(),
            vec![None]
        );
        // An unknown destination names the vocabulary.
        let err = Destination::parse_list("syslog").unwrap_err();
        assert!(err.contains("syslog"), "{err}");
        assert!(err.contains("sessiondir"), "names the vocabulary: {err}");
        // An empty list is an error, not a silent no-op.
        assert!(Destination::parse_list("  ").is_err());
    }

    #[test]
    fn to_directive_parses_and_cascades_replacing_outer() {
        let yaml: serde_json::Value = serde_yaml::from_str(
            r#"
defaults:
  to: sessiondir
routed: |
  table alpha:
    to stdout
    query: v: avg(x)
  table beta:
    query: v: avg(y)
"#,
        )
        .expect("yaml");
        let parsed = parse_report(&yaml).expect("parse report");
        let group = &parsed.report.groups[0];
        let alpha = parsed.report.find("alpha").expect("alpha");
        let beta = parsed.report.find("beta").expect("beta");

        // The item declaration REPLACES the report default rather
        // than unioning with it — `to stdout` means stdout, not
        // "stdout on top of sessiondir".
        assert_eq!(
            parsed.report.effective_style(group, alpha).destinations,
            Some(vec![Destination::Stdout])
        );
        // An item that declared nothing inherits the cascade.
        assert_eq!(
            parsed.report.effective_style(group, beta).destinations,
            Some(vec![Destination::SessionDir])
        );
    }

    #[test]
    fn undeclared_routing_stays_none_so_the_caller_supplies_the_default() {
        // Nothing anywhere in the cascade declared `to`, so the
        // parsed style carries `None` — the render entry point
        // decides, and the two entry points differ (files-only for
        // the automatic run-end render, files+stdout for an
        // explicit `nmbrs report`).
        let yaml: serde_json::Value = serde_yaml::from_str(
            r#"
plain: |
  table alpha:
    query: v: avg(x)
"#,
        )
        .expect("yaml");
        let parsed = parse_report(&yaml).expect("parse report");
        let group = &parsed.report.groups[0];
        let alpha = parsed.report.find("alpha").expect("alpha");
        assert_eq!(
            parsed.report.effective_style(group, alpha).destinations,
            Option::None
        );
        assert_eq!(
            parsed
                .report
                .effective_style(group, alpha)
                .destinations_or(&[Destination::SessionDir]),
            vec![Destination::SessionDir]
        );
    }

    #[test]
    fn routing_round_trips_through_the_persisted_form() {
        // `to` must survive the db round-trip, or an item replayed
        // by `nmbrs report` would land where the replaying command
        // defaults instead of where it was declared.
        let yaml: serde_json::Value = serde_yaml::from_str(
            r#"
routed: |
  table alpha:
    to stdout, sessiondir
    query: v: avg(x)
"#,
        )
        .expect("yaml");
        let parsed = parse_report(&yaml).expect("parse report");
        let item = parsed.report.find("alpha").expect("alpha");
        let persisted = item.to_yaml_directive_string();
        assert!(
            persisted.contains("to stdout, sessiondir"),
            "persisted form carries routing: {persisted}"
        );
        let back = parse_persisted_item(&persisted).expect("round-trip");
        assert_eq!(
            back.style.destinations,
            Some(vec![Destination::Stdout, Destination::SessionDir])
        );
    }

    #[test]
    fn parse_report_stamps_declaration_ordinals() {
        let yaml: serde_json::Value = serde_yaml::from_str(
            r#"
section_a: |
  table alpha:
    query: v: avg(x)
  text zeta as "Z":
   prose
section_b: |
  table beta:
    query: v: avg(y)
"#,
        )
        .expect("yaml");
        let parsed = parse_report(&yaml).expect("parse report");
        let orders: Vec<(String, Option<usize>)> = parsed
            .report
            .items()
            .map(|i| (i.name.clone(), i.order))
            .collect();
        assert_eq!(
            orders,
            vec![
                ("alpha".to_string(), Some(0)),
                ("zeta".to_string(), Some(1)),
                ("beta".to_string(), Some(2)),
            ]
        );
    }

    #[test]
    fn parse_persisted_item_strips_with_table_from_body() {
        // Verbatim shape produced by `to_yaml_directive_string`
        // and written to `session_metadata.report.<name>`.
        // Lines start at column 0 (no indentation in the
        // persisted form). The plot must survive a round-trip
        // with `with_table=true` and no `with-table` line in
        // the body.
        let body = "plot recall_1_mean
label \"ALL 1-recall@R, oracles & PVS\"
target oracles_report.md
legend: br
x: r
y1: avg(recall_mean{k=\"1\"}) by (k,r)
y-ranges: [[0.0,1.0]]
with-table: true";
        let item = parse_persisted_item(body).expect("parse_persisted_item should succeed");
        assert_eq!(item.name, "recall_1_mean");
        assert!(item.with_table, "with_table should be set");
        assert!(
            !item.body.contains("with-table"),
            "body should not contain with-table line; got: {:?}",
            item.body,
        );
    }

    #[test]
    fn with_table_colon_form_consumed_not_in_body() {
        // Regression: the YAML colon form `with-table: true` used
        // to fall through `strip_directive_keyword` (which only
        // accepted space/tab/`=` separators), leaving the line in
        // `item.body`. The plot renderer then saw it as an
        // unknown directive and failed every plot it touched.
        let p = parse(
            r#"
g: |
  plot p1
    over limit
    with-table: true
"#,
        );
        let item = &p.report.groups[0].items[0];
        assert!(item.with_table, "with-table flag should be set");
        assert!(
            !item.body.contains("with-table"),
            "with-table line should be stripped from body, got: {:?}",
            item.body,
        );
    }

    #[test]
    fn unknown_directive_falls_into_body() {
        let p = parse(
            r#"
g: |
  plot p1
    over limit
    where dataset=example
    custom_directive=foo
"#,
        );
        let item = &p.report.groups[0].items[0];
        assert!(item.body.contains("over limit"));
        assert!(item.body.contains("custom_directive=foo"));
    }

    #[test]
    fn label_with_quotes() {
        let p = parse(
            r#"
g: |
  plot p1 over x
    label 'p99 latency'
"#,
        );
        assert_eq!(
            p.report.groups[0].items[0].label.as_deref(),
            Some("p99 latency")
        );
    }

    #[test]
    fn item_name_collides_with_directive_keyword_errors() {
        let v: serde_json::Value = serde_yaml::from_str(
            r#"
g: "plot palette over x"
"#,
        )
        .unwrap();
        assert!(parse_report(&v).is_err());
    }

    #[test]
    fn declaration_order_preserved_across_groups() {
        let p = parse(
            r#"
zzz_block: "plot z over x"
aaa_block: "plot a over x"
mmm_block: "plot m over x"
"#,
        );
        let names: Vec<_> = p.report.groups.iter().map(|g| g.name.clone()).collect();
        assert_eq!(names, vec!["zzz_block", "aaa_block", "mmm_block"]);
    }

    #[test]
    fn style_cascade_root_to_item() {
        let p = parse(
            r#"
defaults:
  palette: wong
  width: 1024

g: |
  defaults palette=tol_muted
  plot p1 over x
    palette=ibm
"#,
        );
        let g = &p.report.groups[0];
        let item = &g.items[0];
        let s = p.report.effective_style(g, item);
        assert_eq!(s.palette.as_deref(), Some("ibm"));
        assert_eq!(s.width, Some(1024.0));
    }

    #[test]
    fn text_kind_keeps_body_verbatim() {
        let p = parse(
            r#"
intro: |
  text Welcome to the report.
   Multi-line prose continues here
   with arbitrary text.
"#,
        );
        let item = &p.report.groups[0].items[0];
        assert_eq!(item.kind, Kind::Text);
        assert_eq!(item.name, "text_001");
        assert!(item.body.contains("Welcome to the report"));
        assert!(item.body.contains("arbitrary text"));
    }

    #[test]
    fn file_directive_scopes_following_items() {
        let p = parse(
            r#"
sections: |
  file my_report.md as 'Markdown Report'
    text Intro paragraph
    plot recall_at_k10 over limit
    table summary metric=recall@.* group_by=p
"#,
        );
        let items = &p.report.groups[0].items;
        assert_eq!(items.len(), 4);
        assert_eq!(items[0].kind, Kind::File);
        assert_eq!(items[0].name, "my_report.md");
        assert_eq!(items[0].label.as_deref(), Some("Markdown Report"));
        // Subsequent items inherit the file as target.
        for it in &items[1..] {
            assert_eq!(
                it.target_file.as_deref(),
                Some("my_report.md"),
                "item {} should target my_report.md, got {:?}",
                it.name,
                it.target_file
            );
        }
    }

    #[test]
    fn file_switch_resets_scope() {
        let p = parse(
            r#"
two_files: |
  file alpha.md as 'Alpha'
    plot p1 over x
  file beta.md
    plot p2 over y
"#,
        );
        let items = &p.report.groups[0].items;
        // Items 0=file alpha, 1=plot p1 (alpha), 2=file beta, 3=plot p2 (beta)
        assert_eq!(items[0].name, "alpha.md");
        assert_eq!(items[1].target_file.as_deref(), Some("alpha.md"));
        assert_eq!(items[2].name, "beta.md");
        assert_eq!(items[3].target_file.as_deref(), Some("beta.md"));
    }

    #[test]
    fn items_before_any_file_have_no_target() {
        let p = parse(
            r#"
mixed: |
  plot orphan over x
  file r.md
    plot inside over x
"#,
        );
        let items = &p.report.groups[0].items;
        assert_eq!(items[0].name, "orphan");
        assert_eq!(items[0].target_file, None);
        assert_eq!(items[2].name, "inside");
        assert_eq!(items[2].target_file.as_deref(), Some("r.md"));
    }

    #[test]
    fn hash_line_comments_stripped() {
        let p = parse(
            r#"
g: |
  # comment line — ignored
  plot p1   # trailing comment
    over limit  # also stripped
    label "Mean recall"  # don't strip inside quotes
"#,
        );
        let item = &p.report.groups[0].items[0];
        assert_eq!(item.kind, Kind::Plot);
        assert_eq!(item.name, "p1");
        assert!(
            item.body.contains("over limit"),
            "body kept: {:?}",
            item.body
        );
        assert!(
            !item.body.contains("trailing"),
            "comment leaked: {:?}",
            item.body
        );
        assert_eq!(item.label.as_deref(), Some("Mean recall"));
    }

    #[test]
    fn auto_text_names_unique_across_document() {
        let p = parse(
            r#"
g1: |
  text First
  text Second
g2: |
  text Third
"#,
        );
        let g1 = &p.report.groups[0];
        assert_eq!(g1.items[0].name, "text_001");
        assert_eq!(g1.items[1].name, "text_002");
        // Counter is global, not per-group, so persistence keys
        // (`report.<name>`) stay unique.
        let g2 = &p.report.groups[1];
        assert_eq!(g2.items[0].name, "text_003");
    }

    #[test]
    fn label_directive_strips_quotes() {
        let p = parse(
            r#"
g: |
  plot p1 over x
    label "My label"
  plot p2 over x
    label 'Another'
"#,
        );
        let items = &p.report.groups[0].items;
        assert_eq!(items[0].label.as_deref(), Some("My label"));
        assert_eq!(items[1].label.as_deref(), Some("Another"));
    }

    // ------------------------------------------------------------------
    // Round-trip emitter — Phase A SRD-64 contract test
    // ------------------------------------------------------------------
    //
    // For every report-grammar shape we accept, the emitter
    // must produce a string that re-parses to an equal AST.
    // That's the contract that lets `--add` write the same
    // grammar back to YAML faithfully.

    fn round_trip_via_group(item: &ReportItem) -> ReportItem {
        let group_body = item.to_yaml_directive_string();
        let yaml = format!(
            "g: |\n{}",
            group_body
                .lines()
                .map(|l| format!("  {l}"))
                .collect::<Vec<_>>()
                .join("\n")
        );
        let parsed = parse(&yaml);
        assert_eq!(
            parsed.report.groups.len(),
            1,
            "round-trip should yield one group, got: {parsed:#?}"
        );
        let items = &parsed.report.groups[0].items;
        assert_eq!(
            items.len(),
            1,
            "round-trip should yield one item, got: {items:#?}"
        );
        items[0].clone()
    }

    fn assert_round_trip_eq(item: ReportItem) {
        let recovered = round_trip_via_group(&item);
        // Compare individual fields for clearer diffs on failure.
        assert_eq!(recovered.kind, item.kind);
        assert_eq!(recovered.name, item.name);
        assert_eq!(recovered.label, item.label);
        assert_eq!(recovered.as_stem, item.as_stem);
        assert_eq!(recovered.style.palette, item.style.palette);
        assert_eq!(recovered.style.line, item.style.line);
        assert_eq!(recovered.style.width, item.style.width);
        assert_eq!(recovered.style.marker, item.style.marker);
        assert_eq!(recovered.style.size, item.style.size);
        assert_eq!(recovered.style.color, item.style.color);
        assert_eq!(recovered.style.figure_width, item.style.figure_width);
        assert_eq!(recovered.style.figure_height, item.style.figure_height);
        assert_eq!(recovered.style.series.len(), item.style.series.len());
        for (a, b) in recovered.style.series.iter().zip(&item.style.series) {
            assert_eq!(a.key, b.key);
            assert_eq!(a.value, b.value);
        }
        // Body comparison is whitespace-tolerant: the emitter
        // re-indents to canonical 2-space, the parser strips
        // leading whitespace anyway.
        let normalize = |s: &str| {
            s.split('\n')
                .map(|l| l.trim())
                .filter(|l| !l.is_empty())
                .collect::<Vec<_>>()
                .join("\n")
        };
        assert_eq!(normalize(&recovered.body), normalize(&item.body));
    }

    #[test]
    fn round_trip_minimal_plot() {
        let item = ReportItem {
            kind: Kind::Plot,
            name: "demo".to_string(),
            body: "over cycle\nmetric=throughput".to_string(),
            ..Default::default()
        };
        assert_round_trip_eq(item);
    }

    #[test]
    fn round_trip_plot_with_label_and_palette() {
        let mut item = ReportItem {
            kind: Kind::Plot,
            name: "recall".to_string(),
            label: Some("Recall@10".to_string()),
            body: "over limit\nby profile".to_string(),
            ..Default::default()
        };
        item.style.palette = Some("wong".to_string());
        assert_round_trip_eq(item);
    }

    #[test]
    fn round_trip_plot_full_style() {
        let mut item = ReportItem {
            kind: Kind::Plot,
            name: "full".to_string(),
            label: Some("Full".to_string()),
            as_stem: Some("plot_full".to_string()),
            body: "over limit\nby profile\nwhere dataset=example\nagg=mean".to_string(),
            ..Default::default()
        };
        item.style.palette = Some("tol_muted".to_string());
        item.style.line = Some("dashed".to_string());
        item.style.width = Some(2.0);
        item.style.marker = Some("circle".to_string());
        item.style.size = Some(4.0);
        item.style.color = Some("#117733".to_string());
        item.style.figure_width = Some(800);
        item.style.figure_height = Some(600);
        assert_round_trip_eq(item);
    }

    #[test]
    fn round_trip_table() {
        let mut item = ReportItem {
            kind: Kind::Table,
            name: "summary".to_string(),
            label: Some("Summary".to_string()),
            body: "metric=recall@.*\ngroup_by=profile".to_string(),
            ..Default::default()
        };
        item.style.palette = Some("wong".to_string());
        assert_round_trip_eq(item);
    }

    #[test]
    fn round_trip_with_series_overrides() {
        let mut item = ReportItem {
            kind: Kind::Plot,
            name: "perseries".to_string(),
            body: "over limit\nby profile".to_string(),
            ..Default::default()
        };
        let s1 = Style {
            line: Some("dashed".to_string()),
            marker: Some("triangle".to_string()),
            ..Default::default()
        };
        item.style.series.push(SeriesOverride {
            key: "profile".to_string(),
            value: "hnsw".to_string(),
            style: s1,
        });
        let s2 = Style {
            line: Some("solid".to_string()),
            ..Default::default()
        };
        item.style.series.push(SeriesOverride {
            key: "profile".to_string(),
            value: "ivf".to_string(),
            style: s2,
        });
        let recovered = round_trip_via_group(&item);
        assert_eq!(recovered.style.series.len(), 2);
        assert_eq!(recovered.style.series[0].key, "profile");
        assert_eq!(recovered.style.series[0].value, "hnsw");
        assert_eq!(
            recovered.style.series[0].style.line.as_deref(),
            Some("dashed")
        );
        assert_eq!(
            recovered.style.series[0].style.marker.as_deref(),
            Some("triangle")
        );
        assert_eq!(recovered.style.series[1].value, "ivf");
        assert_eq!(
            recovered.style.series[1].style.line.as_deref(),
            Some("solid")
        );
    }

    #[test]
    fn round_trip_label_with_internal_quotes_is_escaped() {
        let item = ReportItem {
            kind: Kind::Plot,
            name: "tricky".to_string(),
            label: Some(r#"He said "hi""#.to_string()),
            body: "over cycle".to_string(),
            ..Default::default()
        };
        // The emitter must escape the inner quotes so the
        // parser sees a single label string. (The parser today
        // strips outer quotes only; if it doesn't honour the
        // escape, the test catches that as a real bug to fix.)
        let group_body = item.to_yaml_directive_string();
        assert!(
            group_body.contains(r#"label "He said \"hi\"""#),
            "emitter should escape inner quotes; got:\n{group_body}"
        );
    }

    #[test]
    fn emitter_orders_directives_canonically() {
        // `as` comes before `label`; identity before style;
        // style (scalar fields) before body; body before
        // per-series style overrides. This is the canonical
        // order from vocab::ALL_DIRECTIVES so the round-trip
        // stays stable.
        let mut item = ReportItem {
            kind: Kind::Plot,
            name: "ordered".to_string(),
            label: Some("L".to_string()),
            as_stem: Some("S".to_string()),
            body: "over cycle".to_string(),
            ..Default::default()
        };
        item.style.palette = Some("wong".to_string());
        item.style.series.push(SeriesOverride {
            key: "k".to_string(),
            value: "v".to_string(),
            style: Style::default(),
        });
        let s = item.to_yaml_directive_string();
        let pos = |needle: &str| {
            s.find(needle)
                .unwrap_or_else(|| panic!("missing {needle} in:\n{s}"))
        };
        let pos_as = pos("as S");
        let pos_label = pos("label \"L\"");
        let pos_style = pos("palette=wong");
        let pos_body = pos("over cycle");
        let pos_per_series = pos("style k=v");
        assert!(pos_as < pos_label, "as before label");
        assert!(pos_label < pos_style, "label before style");
        assert!(pos_style < pos_body, "style before body");
        assert!(
            pos_body < pos_per_series,
            "body before per-series style overrides"
        );
    }
}