import json
import os
import shutil
import yt_dlp
from datetime import datetime
from pathlib import Path
from typing import List, Optional

import yt_dlp
from fastapi import FastAPI, File, Form, HTTPException, UploadFile
from fastapi.responses import FileResponse, JSONResponse
from fastapi.staticfiles import StaticFiles

app = FastAPI()

# Configuration
BASE_DIR = Path(__file__).parent
ASSETS_DIR = BASE_DIR / "assets"
IMAGES_DIR = ASSETS_DIR / "images"
VIDEOS_DIR = ASSETS_DIR / "videos"
METADATA_FILE = BASE_DIR / "metadata.json"
STATIC_DIR = BASE_DIR / "static"

# Ensure directories exist
for directory in [IMAGES_DIR, VIDEOS_DIR, STATIC_DIR]:
    directory.mkdir(parents=True, exist_ok=True)

if not METADATA_FILE.exists():
    METADATA_FILE.write_text("[]")

# Mount static files
app.mount("/web", StaticFiles(directory=str(STATIC_DIR), html=True), name="static")

def load_metadata() -> List[dict]:
    try:
        with open(METADATA_FILE, "r") as f:
            return json.load(f)
    except (json.JSONDecodeError, FileNotFoundError):
        return []

def save_metadata(metadata: List[dict]):
    with open(METADATA_FILE, "w") as f:
        json.dump(metadata, f, indent=4)

def get_file_category(content_type: str) -> str:
    if content_type.startswith("image/"):
        return "images"
    elif content_type.startswith("video/"):
        return "videos"
    return "others"

def sanitize_filename(filename: str) -> str:
    # Basic sanitization: remove path traversal attempts and keep only alphanumeric/dots/underscores
    return os.path.basename(filename).replace(" ", "_")

@app.post("/api/files/upload")
async def upload_file(
    file: UploadFile = File(...),
    description: Optional[str] = Form(None),
    uploader: Optional[str] = Form(None)
):
    category = get_file_category(file.content_type)
    if category == "others":
        raise HTTPException(status_code=400, detail="Unsupported file type. Only images and videos are allowed.")

    filename = sanitize_filename(file.filename)
    target_dir = IMAGES_DIR if category == "images" else VIDEOS_DIR
    file_path = target_dir / filename

    # Handle duplicate filenames by appending timestamp
    if file_path.exists():
        timestamp = datetime.now().strftime("%Y%m%d%H%M%S")
        name, ext = os.path.splitext(filename)
        filename = f"{name}_{timestamp}{ext}"
        file_path = target_dir / filename

    try:
        with file_path.open("wb") as buffer:
            shutil.copyfileobj(file.file, buffer)
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Could not save file: {str(e)}")

    metadata_entry = {
        "filename": filename,
        "type": file.content_type,
        "upload_date": datetime.now().isoformat(),
        "file_path": str(file_path.relative_to(BASE_DIR)),
        "description": description,
        "uploader": uploader
    }

    metadata = load_metadata()
    metadata.append(metadata_entry)
    save_metadata(metadata)

    return metadata_entry

@app.post("/api/files/youtube")
async def download_youtube(
    url: str = Form(...),
    description: Optional[str] = Form(None),
    uploader: Optional[str] = Form(None)
):
    ydl_opts = {
        'format': 'bestvideo+bestaudio/best',
        'outtmpl': str(VIDEOS_DIR / '%(title)s.%(ext)s'),
        'quiet': True,
        'no_warnings': True,
    }

    try:
        with yt_dlp.YoutubeDL(ydl_opts) as ydl:
            info = ydl.extract_info(url, download=True)
            file_path_str = ydl.prepare_filename(info)
            file_path = Path(file_path_str)
            filename = file_path.name

            metadata_entry = {
                "filename": filename,
                "type": "video/mp4",  # Simplified, yt-dlp might download different formats
                "upload_date": datetime.now().isoformat(),
                "file_path": str(file_path.relative_to(BASE_DIR)),
                "description": description or info.get('title'),
                "uploader": uploader or info.get('uploader')
            }

            metadata = load_metadata()
            metadata.append(metadata_entry)
            save_metadata(metadata)

            return metadata_entry
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"YouTube download failed: {str(e)}")

@app.get("/api/files")
async def list_files():
    return load_metadata()

@app.get("/api/files/download")
async def download_file(filename: str, stream: bool = False):
    metadata = load_metadata()
    entry = next((item for item in metadata if item["filename"] == filename), None)

    if not entry:
        raise HTTPException(status_code=404, detail="File not found in metadata")

    file_path = BASE_DIR / entry["file_path"]
    if not file_path.exists():
        raise HTTPException(status_code=404, detail="File not found on disk")

    # If stream is True, we use 'inline' so the browser can play it
    disposition = "inline" if stream else "attachment"

    return FileResponse(
        path=file_path,
        filename=filename if not stream else None,
        media_type=entry["type"],
        content_disposition_type=disposition
    )

@app.delete("/api/files")
async def delete_file(filename: str):
    metadata = load_metadata()
    entry_index = next((i for i, item in enumerate(metadata) if item["filename"] == filename), None)

    if entry_index is None:
        raise HTTPException(status_code=404, detail="File not found in metadata")

    entry = metadata[entry_index]
    file_path = BASE_DIR / entry["file_path"]

    # Delete from filesystem
    try:
        if file_path.exists():
            file_path.unlink()
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Could not delete file from disk: {str(e)}")

    # Remove from metadata
    metadata.pop(entry_index)
    save_metadata(metadata)

    return {"message": f"File {filename} deleted successfully"}

if __name__ == "__main__":
    import uvicorn
    uvicorn.run(app, host="0.0.0.0", port=8000)