"""Ad generation endpoints (single, batch, image, strategies, models)."""

import os
from typing import Literal, Optional
from fastapi import APIRouter, HTTPException, Depends
from fastapi.responses import FileResponse, Response as FastAPIResponse

from api.schemas import (
    GenerateRequest,
    GenerateResponse,
    GenerateBatchRequest,
    BatchResponse,
)
from services.generator import ad_generator
from services.auth_dependency import get_current_user
from config import settings

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


@router.post("/generate", response_model=GenerateResponse)
async def generate(
    request: GenerateRequest,
    username: str = Depends(get_current_user),
):
    """
    Generate a single ad creative.
    Requires authentication. Uses randomization for strategies, hooks, visuals.
    """
    try:
        return await ad_generator.generate_ad(
            niche=request.niche,
            num_images=request.num_images,
            image_model=request.image_model,
            username=username,
            target_audience=request.target_audience,
            offer=request.offer,
            use_trending=request.use_trending,
            trending_context=request.trending_context,
        )
    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))


@router.post("/generate/batch", response_model=BatchResponse)
async def generate_batch(
    request: GenerateBatchRequest,
    username: str = Depends(get_current_user),
):
    """
    Generate multiple ad creatives in batch.
    Requires authentication. Each ad is unique due to randomization.
    """
    try:
        results = await ad_generator.generate_batch(
            niche=request.niche,
            count=request.count,
            images_per_ad=request.images_per_ad,
            image_model=request.image_model,
            username=username,
            method=request.method,
            target_audience=request.target_audience,
            offer=request.offer,
        )
        return {"count": len(results), "ads": results}
    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))


@router.get("/image/{filename}")
async def get_image(filename: str):
    """Get a generated image by filename."""
    filepath = os.path.join(settings.output_dir, filename)
    if not os.path.exists(filepath):
        raise HTTPException(status_code=404, detail="Image not found")
    return FileResponse(filepath)


@router.get("/api/download-image")
async def download_image_proxy(
    image_url: Optional[str] = None,
    image_id: Optional[str] = None,
    username: str = Depends(get_current_user),
):
    """
    Proxy endpoint to download images, avoiding CORS.
    Can fetch from external URLs (R2, Replicate) or local files.
    """
    import httpx

    from services.database import db_service

    filename = None
    if image_id:
        ad = await db_service.get_ad_creative(image_id)
        if not ad:
            raise HTTPException(status_code=404, detail="Ad not found")
        if ad.get("username") != username:
            raise HTTPException(status_code=403, detail="Access denied")
        if not image_url:
            image_url = ad.get("r2_url") or ad.get("image_url")
            filename = ad.get("image_filename")
        else:
            metadata = ad.get("metadata", {})
            if metadata.get("original_r2_url") == image_url or metadata.get("original_image_url") == image_url:
                filename = metadata.get("original_image_filename")

    if not image_url:
        raise HTTPException(status_code=400, detail="No image URL provided")

    try:
        if not image_url.startswith(("http://", "https://")):
            filepath = os.path.join(settings.output_dir, image_url)
            if os.path.exists(filepath):
                return FileResponse(filepath, filename=filename or os.path.basename(filepath))
            raise HTTPException(status_code=404, detail="Image file not found")
        async with httpx.AsyncClient(timeout=30.0) as client:
            response = await client.get(image_url)
            response.raise_for_status()
            content_type = response.headers.get("content-type", "image/png")
            if not filename:
                filename = image_url.split("/")[-1].split("?")[0]
                if not filename or "." not in filename:
                    filename = "image.png"
            return FastAPIResponse(
                content=response.content,
                media_type=content_type,
                headers={
                    "Content-Disposition": f'attachment; filename="{filename}"',
                    "Cache-Control": "public, max-age=3600",
                },
            )
    except httpx.HTTPError as e:
        raise HTTPException(status_code=502, detail=f"Failed to fetch image: {str(e)}")
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error downloading image: {str(e)}")


@router.get("/api/models")
async def list_image_models():
    """
    List all available image generation models.
    """
    from services.image import MODEL_REGISTRY

    preferred_order = ["nano-banana", "nano-banana-pro", "z-image-turbo", "imagen-4-ultra", "recraft-v3", "ideogram-v3", "photon", "seedream-3"]
    models = []
    for key in preferred_order:
        if key in MODEL_REGISTRY:
            config = MODEL_REGISTRY[key]
            models.append({
                "key": key,
                "id": config["id"],
                "uses_dimensions": config.get("uses_dimensions", False),
            })
    for key, config in MODEL_REGISTRY.items():
        if key not in preferred_order:
            models.append({
                "key": key,
                "id": config["id"],
                "uses_dimensions": config.get("uses_dimensions", False),
            })
    models.append({
        "key": "gpt-image-1.5",
        "id": "openai/gpt-image-1.5",
        "uses_dimensions": True,
    })
    return {"models": models, "default": "nano-banana"}


@router.get("/strategies/{niche}")
async def get_strategies(niche: Literal["home_insurance", "glp1", "auto_insurance"]):
    """Get available psychological strategies for a niche."""
    from data import home_insurance, glp1, auto_insurance

    if niche == "home_insurance":
        data = home_insurance.get_niche_data()
    elif niche == "auto_insurance":
        data = auto_insurance.get_niche_data()
    else:
        data = glp1.get_niche_data()

    strategies = {}
    for name, strategy in data["strategies"].items():
        strategies[name] = {
            "name": strategy["name"],
            "description": strategy["description"],
            "hook_count": len(strategy["hooks"]),
            "sample_hooks": strategy["hooks"][:3],
        }
    return {
        "niche": niche,
        "total_strategies": len(strategies),
        "total_hooks": len(data["all_hooks"]),
        "strategies": strategies,
    }