import re

from fastapi import APIRouter, BackgroundTasks, HTTPException
from pydantic import BaseModel

from app.schemas.annotation import StudentAnnotation
from app.services.annotation_service import get_annotation_service
from app.services.project_service import ProjectService

router = APIRouter(prefix="/annotations", tags=["annotations"])
_svc = get_annotation_service()


def _require_project_document(project_id: str, document_id: str) -> None:
    if not re.fullmatch(r"[A-Za-z0-9][A-Za-z0-9_-]{0,127}", project_id):
        raise HTTPException(404, "Project document not found")
    if not re.fullmatch(r"[0-9a-f]{64}", document_id):
        raise HTTPException(404, "Project document not found")
    project = ProjectService().load(project_id)
    if project is None or not any(item.file_id == document_id for item in project.files):
        raise HTTPException(404, "Project document not found")


class PatchNoteRequest(BaseModel):
    note_text: str


def _refresh_annotation_evidence(project_id: str, document_id: str) -> None:
    try:
        from app.rag.evidence_ingestion import EvidenceIngestionService

        EvidenceIngestionService().refresh_annotations(project_id, document_id)
    except KeyError:
        pass


@router.get("/stt-status")
def check_stt_status():
    from app.services.voice_transcription_service import VoiceTranscriptionService
    stt = VoiceTranscriptionService.get()
    return {
        "available": stt.is_available,
        "is_loading": stt.is_model_loading()
    }


@router.get("/{document_id}")
def list_annotations(document_id: str, project_id: str):
    _require_project_document(project_id, document_id)
    return [
        annotation.model_dump()
        for annotation in _svc.get_for_project_document(project_id, document_id)
    ]


@router.post("")
def create_annotation(annotation: StudentAnnotation, background_tasks: BackgroundTasks):
    _require_project_document(annotation.project_id, annotation.document_id)
    created = _svc.create(annotation)
    background_tasks.add_task(
        _refresh_annotation_evidence,
        created.project_id,
        created.document_id,
    )
    return created.model_dump()


@router.patch("/{annotation_id}")
def patch_annotation(annotation_id: str, req: PatchNoteRequest, background_tasks: BackgroundTasks):
    updated = _svc.patch_note(annotation_id, req.note_text)
    if not updated:
        raise HTTPException(404, f"Annotation {annotation_id} not found")
    background_tasks.add_task(
        _refresh_annotation_evidence,
        updated.project_id,
        updated.document_id,
    )
    return updated.model_dump()


@router.delete("/{annotation_id}")
def delete_annotation(annotation_id: str, background_tasks: BackgroundTasks):
    existing = _svc.get(annotation_id)
    ok = _svc.delete(annotation_id)
    if not ok:
        raise HTTPException(404, f"Annotation {annotation_id} not found")
    if existing:
        background_tasks.add_task(
            _refresh_annotation_evidence,
            existing.project_id,
            existing.document_id,
        )
    return {"status": "deleted"}