"""GWÖ-Antragsprüfer — FastAPI Webapp."""

import uuid
from pathlib import Path
from typing import Optional

from fastapi import FastAPI, File, Form, UploadFile, Request, BackgroundTasks, HTTPException
from fastapi.responses import HTMLResponse, FileResponse, JSONResponse, Response
from starlette.middleware.base import BaseHTTPMiddleware
from fastapi.staticfiles import StaticFiles
from fastapi.templating import Jinja2Templates
from slowapi import Limiter, _rate_limit_exceeded_handler
from slowapi.util import get_remote_address
from slowapi.errors import RateLimitExceeded

from .config import settings
from .database import (
    init_db, get_job, create_job, update_job,
    get_all_assessments, get_assessment, upsert_assessment, import_json_assessments,
    search_assessments
)
from .parlamente import get_adapter, ADAPTERS
from .bundeslaender import alle_bundeslaender
from .analyzer import analyze_antrag
from .report import generate_html_report, generate_pdf_report
from .embeddings import (
    init_embeddings_db, get_programme_info, get_indexing_status,
    index_programm, PROGRAMME
)

app = FastAPI(
    title=settings.app_name,
    version=settings.app_version,
    docs_url=None,      # Disable /docs in production
    redoc_url=None,     # Disable /redoc in production
    openapi_url=None,   # Disable /openapi.json in production
)


# Rate-Limiter — fängt Resource-Exhaustion auf den teuren POST-Endpoints
# (LLM-Calls + Indexing). Issue #57 Befund #1 (HIGH). Default in-memory
# Storage; für mehrere Worker müsste man auf Redis umstellen, solange wir
# auf einem Container laufen reicht das Default-Storage.
limiter = Limiter(key_func=get_remote_address, default_limits=[])
app.state.limiter = limiter
app.add_exception_handler(RateLimitExceeded, _rate_limit_exceeded_handler)


# Security Headers Middleware
class SecurityHeadersMiddleware(BaseHTTPMiddleware):
    async def dispatch(self, request: Request, call_next):
        response = await call_next(request)
        response.headers["X-Content-Type-Options"] = "nosniff"
        response.headers["X-Frame-Options"] = "DENY"
        response.headers["X-XSS-Protection"] = "1; mode=block"
        response.headers["Referrer-Policy"] = "strict-origin-when-cross-origin"
        response.headers["Permissions-Policy"] = "geolocation=(), microphone=(), camera=()"
        # CSP: Allow self, inline styles (for templates), and PDF viewer
        response.headers["Content-Security-Policy"] = (
            "default-src 'self'; "
            "style-src 'self' 'unsafe-inline'; "
            "script-src 'self' 'unsafe-inline'; "
            "img-src 'self' data:; "
            "frame-ancestors 'none';"
        )
        return response

app.add_middleware(SecurityHeadersMiddleware)


# Setup directories
settings.data_dir.mkdir(exist_ok=True)
settings.reports_dir.mkdir(exist_ok=True)

# Static files and templates
static_dir = Path(__file__).parent / "static"
templates_dir = Path(__file__).parent / "templates"
static_dir.mkdir(exist_ok=True)
templates_dir.mkdir(exist_ok=True)

app.mount("/static", StaticFiles(directory=static_dir), name="static")
templates = Jinja2Templates(directory=str(templates_dir))


@app.on_event("startup")
async def startup():
    await init_db()
    init_embeddings_db()
    # JSON import disabled - all assessments now live in SQLite DB only
    # Legacy import would overwrite new v5 assessments with old format
    # count = await import_json_assessments(settings.data_dir / "assessments")
    # if count > 0:
    #     print(f"Imported {count} assessments from JSON files")


@app.get("/", response_class=HTMLResponse)
async def index(request: Request):
    """Landing page with upload form."""
    # Frontend-Liste: synthetischer "ALL"-Eintrag (Bundesweit) zuerst, dann
    # die echten Bundesländer aus der Konfig. Der "ALL"-Code ist eine reine
    # Frontend/API-Konvention, kein Eintrag in bundeslaender.py.
    bl_list = [{"code": "ALL", "name": "🌍 Bundesweit", "active": True}]
    bl_list.extend(
        {"code": bl.code, "name": bl.name, "active": bl.aktiv}
        for bl in alle_bundeslaender()
    )
    # Map code → parlament_name, damit das Frontend ohne extra Backend-Call
    # für jeden Antrag den Parlamentsnamen anzeigen kann.
    parlament_names = {
        bl.code: bl.parlament_name for bl in alle_bundeslaender()
    }
    return templates.TemplateResponse("index.html", {
        "request": request,
        "app_name": settings.app_name,
        "bundeslaender": bl_list,
        "parlament_names": parlament_names,
    })


@app.post("/analyze")
@limiter.limit("10/minute")
async def start_analysis(
    request: Request,
    background_tasks: BackgroundTasks,
    text: Optional[str] = Form(None),
    file: Optional[UploadFile] = File(None),
    bundesland: str = Form("NRW"),
    model: str = Form("qwen-plus"),
):
    """Start analysis job."""
    if not text and not file:
        raise HTTPException(status_code=400, detail="Entweder Text oder PDF-Datei erforderlich")
    
    # Extract text from PDF if uploaded
    if file and file.filename:
        import fitz  # PyMuPDF
        pdf_bytes = await file.read()
        doc = fitz.open(stream=pdf_bytes, filetype="pdf")
        text = ""
        for page in doc:
            text += page.get_text()
        doc.close()
    
    # Create job
    job_id = str(uuid.uuid4())
    await create_job(job_id, text[:500], bundesland, model)
    
    # Start background analysis
    background_tasks.add_task(run_analysis, job_id, text, bundesland, model)
    
    return JSONResponse({"job_id": job_id, "status": "queued"})


async def run_analysis(job_id: str, text: str, bundesland: str, model: str):
    """Background task for analysis."""
    try:
        await update_job(job_id, status="processing")
        
        # Run LLM analysis
        assessment = await analyze_antrag(text, bundesland, model)
        
        # Generate reports
        html_path = settings.reports_dir / f"{job_id}.html"
        pdf_path = settings.reports_dir / f"{job_id}.pdf"
        
        await generate_html_report(assessment, html_path, bundesland=bundesland)
        await generate_pdf_report(assessment, pdf_path, bundesland=bundesland)

        await update_job(
            job_id,
            status="completed",
            result=assessment.model_dump_json(),
            html_path=str(html_path),
            pdf_path=str(pdf_path),
        )
    except Exception as e:
        await update_job(job_id, status="failed", error=str(e))


@app.get("/status/{job_id}")
async def get_status(job_id: str):
    """Get job status."""
    job = await get_job(job_id)
    if not job:
        raise HTTPException(status_code=404, detail="Job nicht gefunden")
    return JSONResponse({
        "job_id": job_id,
        "status": job["status"],
        "created_at": job["created_at"],
    })


@app.get("/result/{job_id}", response_class=HTMLResponse)
async def get_result(request: Request, job_id: str):
    """Get analysis result as HTML."""
    job = await get_job(job_id)
    if not job:
        raise HTTPException(status_code=404, detail="Job nicht gefunden")
    if job["status"] != "completed":
        raise HTTPException(status_code=400, detail=f"Job noch nicht fertig: {job['status']}")
    
    html_path = Path(job["html_path"])
    if html_path.exists():
        return HTMLResponse(html_path.read_text())
    
    raise HTTPException(status_code=500, detail="Report nicht gefunden")


@app.get("/result/{job_id}/pdf")
async def get_pdf(job_id: str):
    """Download PDF report."""
    job = await get_job(job_id)
    if not job:
        raise HTTPException(status_code=404, detail="Job nicht gefunden")
    if job["status"] != "completed":
        raise HTTPException(status_code=400, detail=f"Job noch nicht fertig: {job['status']}")
    
    pdf_path = Path(job["pdf_path"])
    if pdf_path.exists():
        return FileResponse(
            pdf_path,
            media_type="application/pdf",
            filename=f"gwoe-bericht-{job_id[:8]}.pdf"
        )
    
    raise HTTPException(status_code=500, detail="PDF nicht gefunden")


# API: Load assessments from database
@app.get("/api/assessments")
async def list_assessments(bundesland: Optional[str] = None):
    """Return assessments from database, optionally filtered by Bundesland.

    ``bundesland="ALL"`` and missing parameter both mean "no filter".
    """
    rows = await get_all_assessments(bundesland)

    # Convert DB format to frontend format
    assessments = []
    for row in rows:
        assessments.append({
            "drucksache": row.get("drucksache"),
            "title": row.get("title"),
            "fraktionen": row.get("fraktionen", []),
            "datum": row.get("datum"),
            "link": row.get("link"),
            "bundesland": row.get("bundesland"),
            "gwoeScore": row.get("gwoe_score"),
            "gwoeBegründung": row.get("gwoe_begruendung"),
            "gwoeMatrix": row.get("gwoe_matrix", []),
            "gwoeSchwerpunkt": row.get("gwoe_schwerpunkt", []),
            "wahlprogrammScores": row.get("wahlprogramm_scores", []),
            "verbesserungen": row.get("verbesserungen", []),
            "stärken": row.get("staerken", []),
            "schwächen": row.get("schwaechen", []),
            "empfehlung": row.get("empfehlung"),
            "empfehlungSymbol": row.get("empfehlung_symbol"),
            "verbesserungspotenzial": row.get("verbesserungspotenzial"),
            "themen": row.get("themen", []),
            "antragZusammenfassung": row.get("antrag_zusammenfassung"),
            "antragKernpunkte": row.get("antrag_kernpunkte", []),
        })

    return assessments


# API: Get single assessment (use query param for drucksache with /)
@app.get("/api/assessment")
async def get_single_assessment(drucksache: str):
    """Get a single assessment by drucksache ID."""
    row = await get_assessment(drucksache)
    if not row:
        raise HTTPException(status_code=404, detail="Assessment nicht gefunden")
    
    return {
        "drucksache": row.get("drucksache"),
        "title": row.get("title"),
        "fraktionen": row.get("fraktionen", []),
        "datum": row.get("datum"),
        "link": row.get("link"),
        "bundesland": row.get("bundesland"),
        "gwoeScore": row.get("gwoe_score"),
        "gwoeBegründung": row.get("gwoe_begruendung"),
        "gwoeMatrix": row.get("gwoe_matrix", []),
        "gwoeSchwerpunkt": row.get("gwoe_schwerpunkt", []),
        "wahlprogrammScores": row.get("wahlprogramm_scores", []),
        "verbesserungen": row.get("verbesserungen", []),
        "stärken": row.get("staerken", []),
        "schwächen": row.get("schwaechen", []),
        "empfehlung": row.get("empfehlung"),
        "empfehlungSymbol": row.get("empfehlung_symbol"),
        "verbesserungspotenzial": row.get("verbesserungspotenzial"),
        "themen": row.get("themen", []),
        "antragZusammenfassung": row.get("antrag_zusammenfassung"),
        "antragKernpunkte": row.get("antrag_kernpunkte", []),
    }


# API: Generate PDF on demand for an assessment
@app.get("/api/assessment/pdf")
async def download_assessment_pdf(drucksache: str):
    """Generate and download PDF for an assessment."""
    from .models import Assessment
    
    row = await get_assessment(drucksache)
    if not row:
        raise HTTPException(status_code=404, detail="Assessment nicht gefunden")
    
    # Check if PDF already exists
    safe_name = drucksache.replace("/", "-")
    pdf_path = settings.reports_dir / f"{safe_name}.pdf"
    
    if not pdf_path.exists():
        # Convert DB row to Assessment model for report generation
        assessment_data = {
            "drucksache": row.get("drucksache"),
            "title": row.get("title"),
            "fraktionen": row.get("fraktionen", []),
            "datum": row.get("datum"),
            "link": row.get("link"),
            "gwoe_score": row.get("gwoe_score") or 0,
            "gwoe_begruendung": row.get("gwoe_begruendung") or "",
            "gwoe_matrix": row.get("gwoe_matrix", []),
            "gwoe_schwerpunkt": row.get("gwoe_schwerpunkt", []),
            "wahlprogramm_scores": row.get("wahlprogramm_scores", []),
            "verbesserungen": row.get("verbesserungen", []),
            "staerken": row.get("staerken", []),
            "schwaechen": row.get("schwaechen", []),
            "empfehlung": row.get("empfehlung") or "",
            "empfehlung_symbol": row.get("empfehlung_symbol") or "",
            "verbesserungspotenzial": row.get("verbesserungspotenzial") or "",
            "themen": row.get("themen", []),
            "antrag_zusammenfassung": row.get("antrag_zusammenfassung") or "",
            "antrag_kernpunkte": row.get("antrag_kernpunkte", []),
        }
        
        try:
            assessment = Assessment(**assessment_data)
            await generate_pdf_report(
                assessment,
                pdf_path,
                bundesland=row.get("bundesland"),
            )
        except Exception as e:
            raise HTTPException(status_code=500, detail=f"PDF-Generierung fehlgeschlagen: {e}")
    
    return FileResponse(
        pdf_path,
        media_type="application/pdf",
        filename=f"gwoe-{safe_name}.pdf"
    )


# API: Search internal DB only
@app.get("/api/search")
async def search_internal(
    q: str,
    bundesland: str = "NRW",
    limit: int = 50
):
    """
    Search internal assessments database only.
    """
    db_results = await search_assessments(q, bundesland, limit)
    
    results = []
    for row in db_results:
        results.append({
            "drucksache": row.get("drucksache"),
            "title": row.get("title"),
            "fraktionen": row.get("fraktionen", []),
            "datum": row.get("datum"),
            "link": row.get("link"),
            "bundesland": bundesland,
            "gwoeScore": row.get("gwoe_score"),
            "themen": row.get("themen", []),
            "status": "checked",
        })
    
    return results


# API: Search external parliament portal (Landtag)
@app.get("/api/search-landtag")
async def search_landtag(
    q: str,
    bundesland: str = "NRW",
    limit: int = 20
):
    """
    Search external parliament portal (e.g., NRW OPAL).
    Returns results that can be analyzed with "Jetzt prüfen".

    Requires a concrete Bundesland — the special "ALL" / Bundesweit mode
    cannot pick a single Landtag adapter and is rejected with HTTP 400.
    """
    if not bundesland or bundesland == "ALL":
        raise HTTPException(
            status_code=400,
            detail="Landtag-Suche benötigt ein konkretes Bundesland",
        )
    adapter = get_adapter(bundesland)
    if not adapter:
        return {"error": f"Bundesland {bundesland} noch nicht unterstützt"}
    
    try:
        external = await adapter.search(q, limit)
        results = []
        for doc in external:
            results.append({
                "drucksache": doc.drucksache,
                "title": doc.title,
                "fraktionen": doc.fraktionen,
                "datum": doc.datum,
                "link": doc.link,
                "bundesland": bundesland,
                "typ": doc.typ,
                "gwoeScore": None,
                "status": "unchecked",
            })
        return results
    except Exception as e:
        print(f"Landtag search error: {e}")
        return {"error": f"Suchfehler: {str(e)}"}


# API: Analyze a document from parliament portal
@app.post("/api/analyze-drucksache")
@limiter.limit("10/minute")
async def analyze_drucksache(
    request: Request,
    background_tasks: BackgroundTasks,
    drucksache: str = Form(...),
    bundesland: str = Form("NRW"),
    model: str = Form("qwen-plus")
):
    """
    Download a document from parliament portal and analyze it.
    """
    # Check if already analyzed
    existing = await get_assessment(drucksache)
    if existing:
        return {"status": "already_checked", "drucksache": drucksache}
    
    # Get adapter and download
    adapter = get_adapter(bundesland)
    if not adapter:
        raise HTTPException(status_code=400, detail=f"Bundesland {bundesland} nicht unterstützt")
    
    # Download text
    text = await adapter.download_text(drucksache)
    if not text:
        raise HTTPException(status_code=404, detail=f"Dokument {drucksache} nicht gefunden")
    
    # Get document metadata
    doc = await adapter.get_document(drucksache)
    
    # Create job
    job_id = str(uuid.uuid4())
    await create_job(job_id, text[:500], bundesland, model)
    
    # Start background analysis
    background_tasks.add_task(
        run_drucksache_analysis, 
        job_id, drucksache, text, bundesland, model, doc
    )
    
    return {"status": "queued", "job_id": job_id, "drucksache": drucksache}


async def run_drucksache_analysis(
    job_id: str, 
    drucksache: str, 
    text: str, 
    bundesland: str, 
    model: str,
    doc
):
    """Background task for drucksache analysis."""
    try:
        await update_job(job_id, status="processing")
        
        # Run LLM analysis
        assessment = await analyze_antrag(text, bundesland, model)
        
        # Prepare data for DB
        assessment_data = {
            "drucksache": drucksache,
            "title": assessment.title or (doc.title if doc else f"Drucksache {drucksache}"),
            "fraktionen": assessment.fraktionen,
            "datum": assessment.datum or (doc.datum if doc else ""),
            "link": doc.link if doc else "",
            "bundesland": bundesland,
            "gwoeScore": assessment.gwoe_score,
            "gwoeBegründung": assessment.gwoe_begruendung,
            "gwoeMatrix": [m.model_dump() for m in assessment.gwoe_matrix],
            "gwoeSchwerpunkt": assessment.gwoe_schwerpunkt,
            "wahlprogrammScores": [w.model_dump() for w in assessment.wahlprogramm_scores],
            "verbesserungen": [v.model_dump() for v in assessment.verbesserungen],
            "stärken": assessment.staerken,
            "schwächen": assessment.schwaechen,
            "empfehlung": assessment.empfehlung,
            "empfehlungSymbol": assessment.empfehlung_symbol,
            "verbesserungspotenzial": assessment.verbesserungspotenzial,
            "themen": assessment.themen,
            "antragZusammenfassung": assessment.antrag_zusammenfassung,
            "antragKernpunkte": assessment.antrag_kernpunkte,
            "source": "webapp",
            "model": model,
        }
        
        # Save to DB
        await upsert_assessment(assessment_data)
        
        # Generate reports
        html_path = settings.reports_dir / f"{job_id}.html"
        pdf_path = settings.reports_dir / f"{job_id}.pdf"

        await generate_html_report(assessment, html_path, bundesland=bundesland)
        await generate_pdf_report(assessment, pdf_path, bundesland=bundesland)

        await update_job(
            job_id,
            status="completed",
            result=assessment.model_dump_json(),
            html_path=str(html_path),
            pdf_path=str(pdf_path),
        )
    except Exception as e:
        import traceback
        print(f"ERROR in run_drucksache_analysis for {drucksache}: {e}")
        print(traceback.format_exc())
        await update_job(job_id, status="failed", error=str(e))


# API: List available Bundesländer
@app.get("/api/bundeslaender")
async def list_bundeslaender():
    """List available bundesländer with their status.

    Includes the synthetic "ALL" / Bundesweit entry as the first item so
    that the frontend can render it directly. ``parlament_name`` is added
    so the detail view can show the source parliament without an extra
    backend round-trip.
    """
    out = [{
        "code": "ALL",
        "name": "🌍 Bundesweit",
        "parlament_name": None,
        "active": True,
    }]
    out.extend({
        "code": bl.code,
        "name": bl.name,
        "parlament_name": bl.parlament_name,
        "active": bl.aktiv,
    } for bl in alle_bundeslaender())
    return out


# === Quellen / Programme ===

@app.get("/quellen", response_class=HTMLResponse)
async def quellen_page(request: Request):
    """Quellen-Seite mit allen Wahl- und Parteiprogrammen."""
    programmes = get_programme_info()
    status = get_indexing_status()
    
    return templates.TemplateResponse("quellen.html", {
        "request": request,
        "app_name": settings.app_name,
        "programmes": programmes,
        "status": status,
    })


@app.get("/api/programme")
async def list_programme():
    """List all available programmes."""
    return get_programme_info()


@app.get("/api/programme/status")
async def programme_status():
    """Get indexing status of all programmes."""
    return get_indexing_status()


@app.post("/api/programme/index")
@limiter.limit("3/minute")
async def index_programme(
    request: Request,
    background_tasks: BackgroundTasks,
    programm_id: str = Form(None),
    all_programmes: bool = Form(False),
):
    """Index programme(s) for semantic search."""
    pdf_dir = static_dir / "referenzen"
    
    if all_programmes:
        # Index sequentially to avoid DB locks
        async def index_all_sequential():
            for prog_id in PROGRAMME.keys():
                try:
                    index_programm(prog_id, pdf_dir)
                except Exception as e:
                    print(f"Error indexing {prog_id}: {e}")
        background_tasks.add_task(index_all_sequential)
        return {"status": "indexing", "programmes": list(PROGRAMME.keys())}
    
    if programm_id and programm_id in PROGRAMME:
        background_tasks.add_task(index_programm, programm_id, pdf_dir)
        return {"status": "indexing", "programm_id": programm_id}
    
    raise HTTPException(status_code=400, detail="Ungültiges Programm")


# Health check
@app.get("/health")
async def health():
    return {"status": "ok", "version": settings.app_version}