obzenflow_runtime 0.2.4

// SPDX-License-Identifier: MIT OR Apache-2.0
// SPDX-FileCopyrightText: 2025-2026 ObzenFlow Contributors
// https://obzenflow.dev

//! Invocation-terminal, non-disclosing binding authority faults (FLOWIP-132a).

use super::LogicalEffectBindingName;
use crate::stages::common::handler_error::StageFatal;
use obzenflow_core::event::{StageFatalCode, StageFatalReason};
use std::fmt;

/// Closed reason for a declaration/invocation binding disagreement.
#[derive(Clone, Copy, Debug, PartialEq, Eq)]
pub enum BindingMismatchKind {
    Mode,
    ConstructionFamily,
    Evidence,
}

/// Closed, curated failure set for live effect authority.
///
/// Every value carried here is a validated public identifier. Evidence,
/// targets, resolver causes, ports, and family tokens are deliberately absent.
#[derive(Clone, PartialEq, Eq)]
pub struct BindingAuthorityFault {
    kind: BindingAuthorityFaultKind,
}

#[derive(Clone, PartialEq, Eq)]
enum BindingAuthorityFaultKind {
    RegistrationMissing {
        effect_type: &'static str,
        binding: LogicalEffectBindingName,
    },
    ResolutionFailed {
        effect_type: &'static str,
        binding: LogicalEffectBindingName,
        slot: &'static str,
    },
    BindingMismatch {
        effect_type: &'static str,
        binding: Option<LogicalEffectBindingName>,
        kind: BindingMismatchKind,
    },
    TargetInvariantViolation {
        effect_type: &'static str,
        binding: LogicalEffectBindingName,
        slot: &'static str,
        recorded: bool,
    },
}

impl BindingAuthorityFault {
    pub(crate) fn registration_missing(
        effect_type: &'static str,
        binding: LogicalEffectBindingName,
    ) -> Self {
        Self {
            kind: BindingAuthorityFaultKind::RegistrationMissing {
                effect_type: curated_effect_type(effect_type),
                binding,
            },
        }
    }

    pub(crate) fn resolution_failed(
        effect_type: &'static str,
        binding: LogicalEffectBindingName,
        slot: &'static str,
    ) -> Self {
        Self {
            kind: BindingAuthorityFaultKind::ResolutionFailed {
                effect_type: curated_effect_type(effect_type),
                binding,
                slot,
            },
        }
    }

    pub(crate) fn binding_mismatch(
        effect_type: &'static str,
        binding: Option<LogicalEffectBindingName>,
        kind: BindingMismatchKind,
    ) -> Self {
        Self {
            kind: BindingAuthorityFaultKind::BindingMismatch {
                effect_type: curated_effect_type(effect_type),
                binding,
                kind,
            },
        }
    }

    pub(crate) fn target_invariant_violation(
        effect_type: &'static str,
        binding: LogicalEffectBindingName,
        slot: &'static str,
        recorded: bool,
    ) -> Self {
        Self {
            kind: BindingAuthorityFaultKind::TargetInvariantViolation {
                effect_type: curated_effect_type(effect_type),
                binding,
                slot,
                recorded,
            },
        }
    }

    pub(crate) fn stage_fatal(&self) -> StageFatal {
        StageFatal::new(
            StageFatalCode::Configuration,
            self.reason(),
            self.to_string(),
        )
    }

    pub fn reason(&self) -> StageFatalReason {
        match &self.kind {
            BindingAuthorityFaultKind::RegistrationMissing { .. } => {
                StageFatalReason::EffectPortRegistrationMissing
            }
            BindingAuthorityFaultKind::ResolutionFailed { .. } => {
                StageFatalReason::EffectPortResolutionFailed
            }
            BindingAuthorityFaultKind::BindingMismatch { .. } => {
                StageFatalReason::EffectPortBindingMismatch
            }
            BindingAuthorityFaultKind::TargetInvariantViolation { .. } => {
                StageFatalReason::EffectPortTargetInvariantViolation
            }
        }
    }

    pub fn mismatch_kind(&self) -> Option<BindingMismatchKind> {
        match &self.kind {
            BindingAuthorityFaultKind::BindingMismatch { kind, .. } => Some(*kind),
            _ => None,
        }
    }
}

fn curated_effect_type(effect_type: &'static str) -> &'static str {
    if super::binding::validate_effect_type(effect_type).is_ok() {
        effect_type
    } else {
        // Invalid author input must never be reflected through a framework
        // diagnostic, even if an internal invariant accidentally bypasses
        // descriptor materialisation.
        "invalid_effect_type"
    }
}

impl fmt::Display for BindingAuthorityFault {
    fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result {
        match &self.kind {
            BindingAuthorityFaultKind::RegistrationMissing {
                effect_type,
                binding,
            } => write!(
                formatter,
                "binding '{binding}' for effect '{effect_type}' has no installed registration"
            ),
            BindingAuthorityFaultKind::ResolutionFailed {
                effect_type,
                binding,
                slot,
            } => write!(
                formatter,
                "binding '{binding}' for effect '{effect_type}' failed to resolve slot '{slot}'"
            ),
            BindingAuthorityFaultKind::BindingMismatch {
                effect_type,
                binding,
                kind,
            } => {
                let binding = binding
                    .as_ref()
                    .map(LogicalEffectBindingName::as_str)
                    .unwrap_or("<portless>");
                let reason = match kind {
                    BindingMismatchKind::Mode => "binding mode",
                    BindingMismatchKind::ConstructionFamily => "construction family",
                    BindingMismatchKind::Evidence => "binding evidence",
                };
                write!(
                    formatter,
                    "performed effect '{effect_type}' disagrees with binding '{binding}' ({reason})"
                )
            }
            BindingAuthorityFaultKind::TargetInvariantViolation {
                effect_type,
                binding,
                slot,
                recorded,
            } => {
                let source = if *recorded { "recorded" } else { "live" };
                write!(
                    formatter,
                    "{source} target invariant failed for effect '{effect_type}', binding '{binding}', slot '{slot}'"
                )
            }
        }
    }
}

impl fmt::Debug for BindingAuthorityFault {
    fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result {
        formatter.write_str(&self.to_string())
    }
}

impl std::error::Error for BindingAuthorityFault {}