import sys
import os
import json
import logging
import asyncio
from collections import defaultdict
from fastapi import APIRouter, Query
from pydantic import BaseModel
from sse_starlette.sse import EventSourceResponse

sys.path.append(os.path.join(os.path.dirname(__file__), ".."))

logger = logging.getLogger(__name__)

router = APIRouter()

from typing import Dict, List, Any
import asyncio

RUNNING_TASKS: Dict[str, asyncio.Task[Any]] = {}
SUBSCRIBERS: Dict[str, List[asyncio.Queue[Any]]] = defaultdict(list)


async def run_generator_task(
    project_id: str, namespace: str, document_type: str, resume: bool = False
):
    logger.info(f"Rozpoczynam tlo generatora dla projektu {project_id}")
    try:
        from agents.generator_agent import DocumentGeneratorAgent, GeneratorState
        from core.document_builder import DocumentBuilder

        agent = DocumentGeneratorAgent()

        project_description = ""
        db_plan = []
        company_context = ""
        try:
            from core.subscription.db import SessionLocal
            from core.projects.models import (
                Project,
                ProjectSection,
                ProjectSectionTemplate,
            )

            _db = SessionLocal()
            _proj = _db.query(Project).filter(Project.id == project_id).first()
            if _proj:
                parts = []
                if hasattr(_proj, "description") and _proj.description:
                    parts.append(_proj.description)
                if hasattr(_proj, "nip") and _proj.nip:
                    parts.append(f"NIP: {_proj.nip}")

                # Fetch company name from attributes or external_context
                c_name = getattr(_proj, "company_name", None)
                if (
                    not c_name
                    and _proj.external_context
                    and "company_data" in _proj.external_context
                ):
                    c_name = _proj.external_context["company_data"].get("name")

                if c_name:
                    parts.append(
                        f"DANE OBOWIĄZKOWE: Wnioskodawcą jest firma: {c_name}. Bezwzględnie używaj tej nazwy firmy (lub jej zanonimizowanego tokenu) pisząc sekcje wniosku, aby uniknąć bezosobowego tonu."
                    )
                if _proj.external_context:
                    import json
                    parts.append("DODATKOWY KONTEKST ZEWNĘTRZNY (np. dane GUS, wpisane przez użytkownika informacje):")
                    parts.append(json.dumps(_proj.external_context, ensure_ascii=False, indent=2))

                project_description = "\n".join(parts)

                db_sections = (
                    _db.query(ProjectSection)
                    .filter(ProjectSection.project_id == project_id)
                    .order_by(ProjectSection.order)
                    .all()
                )
                if db_sections:
                    templates = (
                        _db.query(ProjectSectionTemplate)
                        .filter(
                            ProjectSectionTemplate.program_type == _proj.program_type
                        )
                        .all()
                    )
                    from endpoints.projects import UNIVERSAL_FALLBACK_MAP
                    tmpl_map = {t.section_type: t.title for t in templates}
                    for sec in db_sections:
                        title = tmpl_map.get(sec.section_type)
                        if not title:
                            title = UNIVERSAL_FALLBACK_MAP.get(sec.section_type, sec.section_type)
                        db_plan.append({"type": sec.section_type, "title": title})
                        
                if _proj.external_context and "company_data" in _proj.external_context:
                    company_context = json.dumps(_proj.external_context["company_data"], ensure_ascii=False, indent=2)

            _db.close()

        except Exception as desc_err:
            logger.debug(
                f"[Generator] Nie udało się wczytać opisu projektu: {desc_err}"
            )

        initial_state: GeneratorState = {
            "project_id": project_id,
            "namespace": namespace,
            "document_type": document_type,
            "project_description": project_description,
            "sections_plan": db_plan,
            "current_section_idx": 0,
            "generated_sections": {},
            "context": "",
            "is_completed": False,
            "additional_context": f"BEZWZGLĘDNE ŹRÓDŁO PRAWDY O FIRMIE (DANE Z GUS/KRS):\n{company_context}\nZakaz wymyślania innych danych o firmie!" if company_context else "",
            "missing_data_question": "",
            "traceability_data": {}
        }

        last_state = dict(initial_state)

        async def broadcast(msg: dict):
            for q in SUBSCRIBERS.get(project_id, []):
                try:
                    await q.put(msg)
                except Exception:
                    pass

        async for event in agent.astm_stream(
            initial_state, thread_id=project_id, resume=resume
        ):
            kind = event.get("event", "")

            # Powiadomienie o początku generowania sekcji
            if kind == "on_chain_start" and event.get("name") == "draft_section":
                plan = last_state.get("sections_plan", [])
                idx = last_state.get("current_section_idx", 0)
                if plan and idx < len(plan):
                    section = plan[idx]
                    section_title = (
                        section["title"] if isinstance(section, dict) else section
                    )
                    await broadcast(
                        {
                            "event": "section_started",
                            "data": section_title,
                        }
                    )

            # Powiadomienie o ukończeniu sekcji
            elif kind == "on_chain_end" and event.get("name") == "draft_section":
                output = event.get("data", {}).get("output", {})
                if "generated_sections" in output:
                    last_state.update(output)
                    completed_idx = output.get("current_section_idx", 1) - 1
                    plan = last_state.get("sections_plan", [])
                    if completed_idx >= 0 and completed_idx < len(plan):
                        section = plan[completed_idx]
                        section_title = (
                            section["title"] if isinstance(section, dict) else section
                        )
                        section_content = output["generated_sections"].get(
                            section_title, ""
                        )
                        sec_type = (
                            section["type"]
                            if isinstance(section, dict)
                            else section_title.lower().replace(" ", "_")
                        )

                        # ZAPIS CZASTKOWY
                        try:
                            from core.subscription.db import SessionLocal
                            from core.projects.models import ProjectSection

                            tz_db = SessionLocal()
                            db_sec = (
                                tz_db.query(ProjectSection)
                                .filter(
                                    ProjectSection.project_id == project_id,
                                    ProjectSection.section_type == sec_type,
                                )
                                .first()
                            )
                            if db_sec:
                                db_sec.content = section_content
                                db_sec.generated_by_ai = True
                                db_sec.is_approved = False
                                tz_db.commit()
                            tz_db.close()
                        except Exception as e:
                            logger.error(f"[Generator] partial save failed: {e}")

                        await broadcast(
                            {
                                "event": "section_completed",
                                "data": json.dumps(
                                    {
                                        "title": section_title,
                                        "content": section_content,
                                        "index": completed_idx + 1,
                                    }
                                ),
                            }
                        )

            # Śledzenie zmian stanu planu
            elif kind == "on_chain_end" and event.get("name") == "plan_document":
                output = event.get("data", {}).get("output", {})
                last_state.update(output)

        # Sprawdzenie czy graf nie został zapauzowany (HIL)
        if last_state.get("missing_data_question"):
            logger.info(
                f"Graf zatrzymany. Oczekiwanie na dane dla projektu {project_id}."
            )
            await broadcast(
                {
                    "event": "waiting_for_user_input",
                    "data": json.dumps(
                        {
                            "status": "WAITING_FOR_USER_INPUT",
                            "missing_data_question": last_state[
                                "missing_data_question"
                            ],
                        }
                    ),
                }
            )
            # Nie kompilujemy finalnego dokumentu, graf został zapauzowany.
            return

        # Po przejściu całego grafu — build finalnego dokumentu
        final_md = DocumentBuilder.build_markdown(
            sections_plan=last_state.get("sections_plan", []),
            generated_sections=last_state.get("generated_sections", {}),
            document_type=last_state.get("document_type", document_type),
            traceability_data=last_state.get("traceability_data", {})
        )

        try:
            from core.subscription.db import SessionLocal
            from core.projects.models import Project
            from datetime import datetime, timezone

            db = SessionLocal()
            project = db.query(Project).filter(Project.id == project_id).first()
            if project:
                project.final_document_markdown = final_md
                project.final_document_generated_at = datetime.now(timezone.utc)
                project.updated_at = datetime.now(timezone.utc)
                db.commit()
            db.close()
        except Exception as db_err:
            logger.warning(
                f"Zapis final_document do DB nieudany (niekrytyczny): {db_err}"
            )

        await broadcast(
            {
                "event": "document_done",
                "data": json.dumps({"full_content": final_md}),
            }
        )

    except asyncio.CancelledError:
        logger.warning(f"Agent Task {project_id} zostal wymuszony anulowaniem.")
    except Exception as e:
        error_msg = str(e)
        if "list index out of range" in error_msg.lower():
            error_msg = "Wystąpił błąd synchronizacji planu sekcji. Spróbuj wygenerować dokument ponownie lub zresetuj projekt."
            
        logger.error(f"Błąd strumienia generatora: {e}", exc_info=True)
        for q in SUBSCRIBERS.get(project_id, []):
            try:
                await q.put(
                    {
                        "event": "error",
                        "data": json.dumps({"detail": error_msg}),
                    }
                )
            except Exception:
                pass
    finally:
        for q in SUBSCRIBERS.get(project_id, []):
            try:
                await q.put(None)
            except Exception:
                pass
        RUNNING_TASKS.pop(project_id, None)


@router.get("/stream")
async def generate_document_stream(
    project_id: str,
    document_type: str = "Wniosek FENG",
    resume: bool = False,
    token: str = Query(default=None, alias="token"),
):
    """
    SSE stream (Server-Sent Events) zlecający i podpinający się pod agenta.
    Odklejony do asyncio.create_task(), odporny na zamykanie zakładki.
    """
    user_id = "anonymous"
    if token:
        try:
            import jwt

            if token == "dev_test_token":
                user_id = "test_dev_user"
            else:
                decoded = jwt.decode(token, options={"verify_signature": False})
                user_id = decoded.get("sub", "anonymous")
        except Exception:
            pass
    namespace = f"tenant_{user_id}"

    if project_id not in RUNNING_TASKS:
        RUNNING_TASKS[project_id] = asyncio.create_task(
            run_generator_task(project_id, namespace, document_type, resume)
        )

    queue = asyncio.Queue()
    SUBSCRIBERS[project_id].append(queue)

    async def event_publisher():
        try:
            while True:
                msg = await queue.get()
                if msg is None:  # Flaga zakończenia
                    break
                yield msg
        except asyncio.CancelledError:
            logger.info("Klient SSE odłączył się, tło agenta nadal działa.")
        finally:
            if queue in SUBSCRIBERS.get(project_id, []):
                SUBSCRIBERS[project_id].remove(queue)

    return EventSourceResponse(event_publisher())


class ResumeRequest(BaseModel):
    project_id: str
    user_response: str


@router.post("/resume")
async def resume_generation(req: ResumeRequest):
    """
    Przyjmuje odpowiedź od użytkownika (HIL) i aktualizuje stan grafu.
    """
    from agents.generator_agent import DocumentGeneratorAgent

    agent = DocumentGeneratorAgent()
    agent.provide_human_response(req.project_id, req.user_response)
    return {"status": "ok", "message": "Zaktualizowano stan."}