# Copyright (c) 2026 PowerOn AG
# All rights reserved.
"""API routes for Private-LLM: health, models, analyze, PDF extract, Ollama status."""

import base64
import json
import re
import logging
from typing import Optional, List

import httpx
from fastapi import APIRouter, HTTPException, Depends, Header

from config import (
    CONFIG, MODEL_MAPPING, PDF_SUPPORT,
    rateLimiter,
    _isVisionModel, _getInternalModelName,
    _extractImagesFromPdf, _renderPdfPageAsImage,
    _verifyApiKey,
    AnalyzeRequest, AnalyzeResponse,
    PdfExtractRequest, ModelInfo,
    HealthResponse, OllamaStatusResponse,
)

logger = logging.getLogger(__name__)

router = APIRouter(tags=["API"])


@router.get("/api/health", response_model=HealthResponse, tags=["System"])
async def _healthCheck():
    """Health check endpoint."""
    ollamaConnected = False
    try:
        async with httpx.AsyncClient(timeout=5.0) as client:
            response = await client.get(f"{CONFIG['ollamaUrl']}/api/tags")
            ollamaConnected = response.status_code == 200
    except Exception:
        pass

    return HealthResponse(
        status="ok",
        service="private-llm",
        pdfSupport=PDF_SUPPORT,
        ollamaConnected=ollamaConnected
    )


@router.get("/api/models", response_model=List[ModelInfo], tags=["Models"])
async def _listModels(authenticated: bool = Depends(_verifyApiKey)):
    """List available models with pricing."""
    models = []
    for externalName, internalName in MODEL_MAPPING.items():
        isVision = _isVisionModel(internalName)
        pricePerCall = 0.10 if isVision else 0.01

        models.append(ModelInfo(
            name=externalName,
            internalName=internalName,
            isVision=isVision,
            pricePerCall=pricePerCall
        ))

    return models


@router.get("/api/ollama/status", response_model=OllamaStatusResponse, tags=["System"])
async def _ollamaStatus():
    """Check Ollama connection status and list available models."""
    try:
        async with httpx.AsyncClient(timeout=10.0) as client:
            response = await client.get(f"{CONFIG['ollamaUrl']}/api/tags")

            if response.status_code != 200:
                return OllamaStatusResponse(
                    connected=False,
                    error=f"Ollama responded with status {response.status_code}"
                )

            data = response.json()
            models = [m.get("name", "") for m in data.get("models", [])]
            visionModels = [m for m in models if _isVisionModel(m)]

            return OllamaStatusResponse(
                connected=True,
                models=models,
                visionModels=visionModels,
                totalModels=len(models)
            )

    except httpx.ConnectError:
        return OllamaStatusResponse(
            connected=False,
            error="Keine Verbindung zu Ollama. Ist Ollama gestartet?"
        )
    except Exception as e:
        return OllamaStatusResponse(
            connected=False,
            error=str(e)
        )


@router.post("/api/analyze", response_model=AnalyzeResponse, tags=["AI"])
async def _analyzeDocument(
    request: AnalyzeRequest,
    xApiKey: Optional[str] = Header(None, alias="X-API-Key")
):
    """
    Analyze a document with AI Vision API.

    Supports both vision models (with images) and text models (without images).

    Authentication:
    - Gateway calls: Must include X-API-Key header
    - Test UI calls: No auth required (same-origin)

    Rate limiting is applied when API key is provided.
    """
    if xApiKey:
        if CONFIG["apiKey"] and xApiKey != CONFIG["apiKey"]:
            raise HTTPException(status_code=401, detail="Invalid API key")
        allowed, info = rateLimiter.isAllowed(xApiKey)
        if not allowed:
            raise HTTPException(
                status_code=429,
                detail=f"Rate limit exceeded. Retry after {info['retryAfter']} seconds.",
                headers={"Retry-After": str(int(info["retryAfter"]) + 1)},
            )
    try:
        internalModelName = _getInternalModelName(request.modelName)
        isVision = _isVisionModel(internalModelName)

        if isVision and not request.imageBase64:
            raise HTTPException(
                status_code=400,
                detail="Kein Bild übermittelt (erforderlich für Vision-Modelle)"
            )

        if not request.prompt:
            raise HTTPException(status_code=400, detail="Kein Prompt übermittelt")

        # Server has 31GB RAM + 22GB GPU - vision models need smaller context
        modelContextLengths = {
            "qwen2.5:7b": 8192,
            "qwen2.5vl:7b": 4096,
            "granite3.2-vision": 4096,
            "granite3.2-vision:latest": 4096,
            "deepseek-ocr": 4096,
            "deepseek-ocr:latest": 4096,
        }
        numCtx = modelContextLengths.get(internalModelName, 4096)

        requestBody = {
            "model": internalModelName,
            "prompt": request.prompt,
            "stream": False,
            "options": {
                "num_ctx": numCtx
            }
        }

        if request.imageBase64:
            requestBody["images"] = [request.imageBase64]

        async with httpx.AsyncClient(timeout=3600.0) as client:
            response = await client.post(
                f"{CONFIG['ollamaUrl']}/api/generate",
                json=requestBody
            )

            if response.status_code == 404:
                raise HTTPException(
                    status_code=404,
                    detail=f'Modell "{internalModelName}" nicht gefunden. Bitte installieren mit: ollama pull {internalModelName}'
                )

            if response.status_code != 200:
                raise HTTPException(
                    status_code=response.status_code,
                    detail=f"Ollama API Fehler: {response.status_code} - {response.text[:200]}"
                )

            responseData = response.json()
            responseText = responseData.get("response", "")

            extractedData = None
            jsonMatch = re.search(r"\{[\s\S]*\}", responseText)

            if jsonMatch:
                try:
                    extractedData = json.loads(jsonMatch.group())
                except json.JSONDecodeError:
                    extractedData = None

            if extractedData is None:
                extractedData = {"response": responseText.strip()}

            return AnalyzeResponse(
                success=True,
                data=extractedData,
                rawResponse=responseText
            )

    except httpx.TimeoutException:
        return AnalyzeResponse(
            success=False,
            error="Zeitüberschreitung bei der Ollama API"
        )
    except httpx.ConnectError:
        return AnalyzeResponse(
            success=False,
            error="Verbindung zu Ollama fehlgeschlagen. Ist Ollama gestartet?"
        )
    except HTTPException:
        raise
    except Exception as e:
        logger.error(f"Error analyzing document: {e}")
        return AnalyzeResponse(
            success=False,
            error=f"Unerwarteter Fehler: {str(e)}"
        )


@router.post("/api/pdf/extract", tags=["PDF"])
async def _extractPdfImages(request: PdfExtractRequest):
    """
    Extract images from a PDF.

    No API key required - this endpoint is for local test UI only,
    not used by gateway (gateway sends images directly).
    """
    if not PDF_SUPPORT:
        raise HTTPException(
            status_code=501,
            detail="PDF-Support nicht verfügbar. Bitte PyMuPDF installieren: pip install pymupdf"
        )

    try:
        pdfBytes = base64.b64decode(request.pdfBase64)

        if request.page is not None:
            result = _renderPdfPageAsImage(pdfBytes, request.page - 1)
            return {"success": True, "image": result}
        else:
            images = _extractImagesFromPdf(pdfBytes, maxPages=5)
            return {
                "success": True,
                "images": images,
                "totalExtracted": len(images)
            }

    except Exception as e:
        raise HTTPException(
            status_code=500,
            detail=f"PDF-Verarbeitungsfehler: {str(e)}"
        )