"""Admin CRUD for reusable parser profiles + generate/preview."""

from __future__ import annotations

from typing import Any

from fastapi import APIRouter, Depends, HTTPException
from pydantic import BaseModel, Field
from sqlalchemy.orm import Session

from contracts.heuristic_profile import HeuristicProfile
from contracts.llm_profile import LlmProfile

from ..database import get_db
from ..deps import verify_admin
from ..models import ParseJob, ParserProfile
from ..schemas import ParserProfileCreate, ParserProfileRead, ParserProfileUpdate
from ..services import parser_builder as builder

router = APIRouter(
    prefix="/admin/parser-profiles",
    tags=["parser-profiles"],
    dependencies=[Depends(verify_admin)],
)


class GenerateRequest(BaseModel):
    sample_post: str = Field(min_length=1)
    hint: str | None = None
    current_profile: dict[str, Any] | None = None


class GenerateResponse(BaseModel):
    profile: dict[str, Any]
    preview: dict[str, str]
    empty_fields: list[str] = Field(default_factory=list)


class PreviewRequest(BaseModel):
    sample_post: str = Field(min_length=1)
    heuristic_profile: dict[str, Any] | None = None
    # Accept alias used by older builder UI
    profile: dict[str, Any] | None = None


class PreviewResponse(BaseModel):
    fields: dict[str, str]
    matched: bool = True
    missing_required: list[str] = Field(default_factory=list)


class PreviewLlmRequest(BaseModel):
    sample_post: str = Field(min_length=1)
    llm_profile: dict[str, Any]


class PreviewLlmResponse(BaseModel):
    fields: dict[str, str]
    events: list[dict[str, str]] = Field(default_factory=list)
    matched: bool = True
    missing_required: list[str] = Field(default_factory=list)
    is_event: bool = True
    matched_count: int = 0


def _validate_heuristic_profile(raw: dict[str, Any] | None) -> dict[str, Any] | None:
    if raw is None:
        return None
    try:
        return HeuristicProfile.model_validate(raw).model_dump()
    except Exception as exc:
        raise HTTPException(status_code=400, detail=f"Invalid heuristic_profile: {exc}") from exc


def _validate_llm_profile(raw: dict[str, Any] | None) -> dict[str, Any] | None:
    if raw is None:
        return None
    try:
        return LlmProfile.model_validate(raw).model_dump()
    except Exception as exc:
        raise HTTPException(status_code=400, detail=f"Invalid llm_profile: {exc}") from exc


def _normalize_kind(kind: str | None) -> str:
    value = (kind or "heuristic").strip().lower()
    if value not in ("heuristic", "llm"):
        raise HTTPException(status_code=400, detail="kind must be heuristic or llm")
    return value


def _profile_status(
    *,
    kind: str,
    heuristic_profile: dict | None,
    llm_profile: dict | None,
    explicit: str | None = None,
) -> str:
    if explicit:
        return explicit
    if kind == "llm":
        return "ready" if llm_profile else "draft"
    return "ready" if heuristic_profile else "draft"


@router.get("/target-fields")
def target_fields():
    return {"fields": builder.get_target_fields()}


@router.get("/llm-defaults")
def llm_defaults():
    from contracts.llm_profile import DEFAULT_EXTRACT_SCHEMA, DEFAULT_INSTRUCTION

    return {
        "instruction": DEFAULT_INSTRUCTION,
        "extract_schema": DEFAULT_EXTRACT_SCHEMA,
        "required_fields": [],
        "multi_event": False,
    }


@router.post("/generate", response_model=GenerateResponse)
async def generate_profile(payload: GenerateRequest):
    if not builder.deepseek_enabled():
        raise HTTPException(
            status_code=503,
            detail="DEEPSEEK_API_KEY is not set on ca-api. Add it to .env for parser generation.",
        )
    try:
        profile = await builder.generate_profile(
            payload.sample_post,
            hint=payload.hint,
            current_profile=payload.current_profile,
        )
    except ValueError as exc:
        raise HTTPException(status_code=400, detail=str(exc)) from exc
    except Exception as exc:
        raise HTTPException(
            status_code=502,
            detail=f"DeepSeek generate failed: {exc}",
        ) from exc
    dumped = profile.model_dump()
    if payload.current_profile and isinstance(payload.current_profile.get("required_fields"), list):
        dumped["required_fields"] = payload.current_profile["required_fields"]
        dumped = HeuristicProfile.model_validate(dumped).model_dump()
    preview = builder.preview_with_profile(payload.sample_post, dumped)
    return GenerateResponse(
        profile=dumped,
        preview=preview,
        empty_fields=builder.empty_preview_fields(preview),
    )


@router.post("/preview", response_model=PreviewResponse)
def preview_profile(payload: PreviewRequest):
    raw = payload.heuristic_profile if payload.heuristic_profile is not None else payload.profile
    if raw is None:
        raise HTTPException(status_code=400, detail="heuristic_profile is required")
    try:
        HeuristicProfile.model_validate(raw)
        fields, matched, missing = builder.match_preview(payload.sample_post, raw)
    except Exception as exc:
        raise HTTPException(status_code=400, detail=str(exc)) from exc
    return PreviewResponse(fields=fields, matched=matched, missing_required=missing)


@router.post("/preview-llm", response_model=PreviewLlmResponse)
async def preview_llm_profile(payload: PreviewLlmRequest):
    if not builder.deepseek_enabled():
        raise HTTPException(
            status_code=503,
            detail="DEEPSEEK_API_KEY is not set on ca-api. Add it to .env for LLM preview.",
        )
    try:
        LlmProfile.model_validate(payload.llm_profile)
        events, fields, matched, missing, is_event, matched_count = await builder.preview_llm_extract(
            payload.sample_post,
            payload.llm_profile,
        )
    except ValueError as exc:
        raise HTTPException(status_code=400, detail=str(exc)) from exc
    except Exception as exc:
        raise HTTPException(
            status_code=502,
            detail=f"DeepSeek LLM preview failed: {exc}",
        ) from exc
    return PreviewLlmResponse(
        fields=fields,
        events=events,
        matched=matched,
        missing_required=missing,
        is_event=is_event,
        matched_count=matched_count,
    )


@router.get("", response_model=list[ParserProfileRead])
def list_profiles(db: Session = Depends(get_db)):
    return db.query(ParserProfile).order_by(ParserProfile.id.desc()).all()


@router.post("", response_model=ParserProfileRead, status_code=201)
def create_profile(payload: ParserProfileCreate, db: Session = Depends(get_db)):
    kind = _normalize_kind(payload.kind)
    heuristic = _validate_heuristic_profile(payload.heuristic_profile)
    llm = _validate_llm_profile(payload.llm_profile)
    if kind == "heuristic" and llm and not heuristic:
        # ignore stray llm blob when creating heuristic
        llm = None
    if kind == "llm" and heuristic and not llm:
        heuristic = None
    profile = ParserProfile(
        name=payload.name.strip(),
        kind=kind,
        sample_post=payload.sample_post or "",
        heuristic_profile=heuristic if kind == "heuristic" else None,
        llm_profile=llm if kind == "llm" else None,
        status=_profile_status(
            kind=kind,
            heuristic_profile=heuristic if kind == "heuristic" else None,
            llm_profile=llm if kind == "llm" else None,
            explicit=payload.status,
        ),
    )
    db.add(profile)
    db.commit()
    db.refresh(profile)
    return profile


@router.get("/{profile_id}", response_model=ParserProfileRead)
def get_profile(profile_id: int, db: Session = Depends(get_db)):
    profile = db.query(ParserProfile).filter(ParserProfile.id == profile_id).first()
    if not profile:
        raise HTTPException(status_code=404, detail="Profile not found")
    return profile


@router.patch("/{profile_id}", response_model=ParserProfileRead)
def update_profile(
    profile_id: int,
    payload: ParserProfileUpdate,
    db: Session = Depends(get_db),
):
    profile = db.query(ParserProfile).filter(ParserProfile.id == profile_id).first()
    if not profile:
        raise HTTPException(status_code=404, detail="Profile not found")

    if payload.name is not None:
        profile.name = payload.name.strip()
    if payload.sample_post is not None:
        profile.sample_post = payload.sample_post
    if payload.kind is not None:
        profile.kind = _normalize_kind(payload.kind)
    kind = _normalize_kind(profile.kind)

    if "heuristic_profile" in payload.model_fields_set:
        profile.heuristic_profile = _validate_heuristic_profile(payload.heuristic_profile)
    if "llm_profile" in payload.model_fields_set:
        profile.llm_profile = _validate_llm_profile(payload.llm_profile)

    # Keep only the blob matching kind
    if kind == "heuristic":
        profile.llm_profile = None
    else:
        profile.heuristic_profile = None

    if payload.status is not None:
        profile.status = payload.status
    elif (
        "heuristic_profile" in payload.model_fields_set
        or "llm_profile" in payload.model_fields_set
        or payload.kind is not None
    ):
        profile.status = _profile_status(
            kind=kind,
            heuristic_profile=profile.heuristic_profile,
            llm_profile=profile.llm_profile,
        )

    db.commit()
    db.refresh(profile)
    return profile


@router.delete("/{profile_id}", status_code=204)
def delete_profile(profile_id: int, db: Session = Depends(get_db)):
    profile = db.query(ParserProfile).filter(ParserProfile.id == profile_id).first()
    if not profile:
        raise HTTPException(status_code=404, detail="Profile not found")

    linked = (
        db.query(ParseJob)
        .filter(ParseJob.profile_id == profile_id, ParseJob.status.in_(("queued", "running")))
        .count()
    )
    if linked:
        raise HTTPException(
            status_code=409,
            detail="Cannot delete profile used by queued/running jobs",
        )

    db.delete(profile)
    db.commit()