"""Contradiction Engine API — detect and manage system contradictions.

See repo root: `docs/trust/ledger-vs-tool-verification.md` for how this relates to
`VerificationLedger` / `tool_verification`.
"""

from fastapi import APIRouter, Depends, HTTPException
from pydantic import BaseModel as PydanticBase
from typing import Any, Dict, List, Optional

router = APIRouter(prefix="/contradictions", tags=["Contradictions"])


class ContradictionCreate(PydanticBase):
    source_a: str
    source_b: str
    claim_a: str
    claim_b: str
    contradiction_type: str = "factual"
    severity: str = "medium"
    detected_by: str = "manual"
    evidence: Optional[Dict[str, Any]] = None


class ContradictionResolve(PydanticBase):
    resolution: str
    status: str = "resolved"


@router.post("/")
async def register_contradiction(body: ContradictionCreate) -> Dict[str, Any]:
    """Register a new contradiction."""
    sev = (body.severity or "").strip().lower()
    if sev in ("v3", "critical") and not (body.evidence or {}):
        raise HTTPException(
            status_code=422,
            detail="severity V3/critical requires non-empty evidence (trust plane receipt)",
        )
    return {
        "status": "registered",
        "source_a": body.source_a,
        "source_b": body.source_b,
        "contradiction_type": body.contradiction_type,
        "severity": body.severity,
    }


@router.get("/")
async def list_contradictions() -> Dict[str, Any]:
    """List active contradictions."""
    return {"contradictions": [], "total": 0}


@router.get("/stats")
async def contradiction_stats() -> Dict[str, Any]:
    """Get contradiction statistics."""
    return {"total": 0, "active": 0, "resolved": 0, "critical_active": 0}


@router.get("/{contradiction_id}")
async def get_contradiction(contradiction_id: str) -> Dict[str, Any]:
    """Get a specific contradiction."""
    return {"id": contradiction_id, "status": "not_found"}


@router.put("/{contradiction_id}/resolve")
async def resolve_contradiction(
    contradiction_id: str, body: ContradictionResolve
) -> Dict[str, Any]:
    """Resolve a contradiction."""
    return {"id": contradiction_id, "status": body.status, "resolution": body.resolution}