# main.py — FastAPI backend entrypoint for dicta2stream

from fastapi import FastAPI, Request, Response, status, Form, UploadFile, File, Depends, HTTPException
from fastapi.responses import HTMLResponse, RedirectResponse, StreamingResponse, JSONResponse
from fastapi.staticfiles import StaticFiles
from fastapi.middleware.cors import CORSMiddleware
from fastapi.middleware.gzip import GZipMiddleware
import os
import io
import traceback
import shutil
import mimetypes
from typing import Optional
from models import User, UploadLog
from sqlmodel import Session, select, SQLModel
from database import get_db, engine
from log import log_violation
import secrets
import time
import json
from datetime import datetime

from dotenv import load_dotenv
load_dotenv()

# Ensure all tables exist at startup
SQLModel.metadata.create_all(engine)

ADMIN_SECRET = os.getenv("ADMIN_SECRET")

import os

debug_mode = os.getenv("DEBUG", "0") in ("1", "true", "True")
from fastapi.responses import JSONResponse
from fastapi.requests import Request as FastAPIRequest
from fastapi.exception_handlers import RequestValidationError
from fastapi.exceptions import HTTPException as FastAPIHTTPException

app = FastAPI(debug=debug_mode)

# --- CORS Middleware for SSE and API access ---
from fastapi.middleware.cors import CORSMiddleware
from fastapi.middleware.gzip import GZipMiddleware

# Add GZip middleware for compression
app.add_middleware(GZipMiddleware, minimum_size=1000)

# Configure CORS
app.add_middleware(
    CORSMiddleware,
    allow_origins=["https://dicta2stream.net", "http://localhost:8000", "http://127.0.0.1:8000"],
    allow_credentials=True,
    allow_methods=["GET", "POST", "OPTIONS"],
    allow_headers=["*"],
    expose_headers=["Content-Type", "Content-Length", "Cache-Control", "ETag", "Last-Modified"],
    max_age=3600,  # 1 hour
)

from fastapi.staticfiles import StaticFiles
import os
if not os.path.exists("data"):
    os.makedirs("data")
# Secure audio file serving endpoint (replaces static mount)
from fastapi.responses import FileResponse
from fastapi import Security

def get_current_user(request: Request, db: Session = Depends(get_db)):
    # Use your existing session/cookie/token mechanism here
    uid = request.headers.get("x-uid") or request.query_params.get("uid") or request.cookies.get("uid")
    if not uid:
        raise HTTPException(status_code=403, detail="Not authenticated")
    user = get_user_by_uid(uid)
    if not user or not user.confirmed:
        raise HTTPException(status_code=403, detail="Invalid user")
    return user

from range_response import range_response

@app.get("/audio/{uid}/{filename}")
def get_audio(uid: str, filename: str, request: Request, db: Session = Depends(get_db)):
    # Allow public access ONLY to stream.opus
    user_dir = os.path.join("data", uid)
    file_path = os.path.join(user_dir, filename)
    real_user_dir = os.path.realpath(user_dir)
    real_file_path = os.path.realpath(file_path)
    if not real_file_path.startswith(real_user_dir):
        raise HTTPException(status_code=403, detail="Path traversal detected")
    if not os.path.isfile(real_file_path):
        raise HTTPException(status_code=404, detail="File not found")
    if filename == "stream.opus":
        # Use range_response for browser seeking support
        return range_response(request, real_file_path, content_type="audio/ogg")
    # Otherwise, require authentication and owner check
    try:
        from fastapi import Security
        current_user = get_current_user(request, db)
    except Exception:
        raise HTTPException(status_code=403, detail="Not allowed")
    if uid != current_user.username:
        raise HTTPException(status_code=403, detail="Not allowed")
    return FileResponse(real_file_path, media_type="audio/ogg")

if debug_mode:
    print("[DEBUG] FastAPI running in debug mode.")

# Global error handler to always return JSON
from slowapi.errors import RateLimitExceeded
from models import get_user_by_uid, UserQuota

@app.exception_handler(RateLimitExceeded)
async def rate_limit_handler(request: Request, exc: RateLimitExceeded):
    return JSONResponse(status_code=429, content={"detail": "Rate limit exceeded. Please try again later."})

@app.exception_handler(FastAPIHTTPException)
async def http_exception_handler(request: FastAPIRequest, exc: FastAPIHTTPException):
    return JSONResponse(status_code=exc.status_code, content={"detail": exc.detail})

@app.exception_handler(RequestValidationError)
async def validation_exception_handler(request: FastAPIRequest, exc: RequestValidationError):
    return JSONResponse(status_code=422, content={"detail": exc.errors()})

@app.exception_handler(Exception)
async def generic_exception_handler(request: FastAPIRequest, exc: Exception):
    return JSONResponse(status_code=500, content={"detail": str(exc)})

# include routers from submodules
from register import router as register_router
from magic import router as magic_router
from upload import router as upload_router
from streams import router as streams_router
from list_user_files import router as list_user_files_router

app.include_router(streams_router)

from list_streams import router as list_streams_router
from account_router import router as account_router

app.include_router(account_router)
app.include_router(register_router)
app.include_router(magic_router)
app.include_router(upload_router)
app.include_router(list_user_files_router)
app.include_router(list_streams_router)

# Serve static files
app.mount("/static", StaticFiles(directory="static"), name="static")

# Serve audio files
os.makedirs("data", exist_ok=True)  # Ensure the data directory exists
app.mount("/audio", StaticFiles(directory="data"), name="audio")

@app.post("/log-client")
async def log_client(request: Request):
    try:
        data = await request.json()
        msg = data.get("msg", "")
        ip = request.client.host
        timestamp = datetime.utcnow().isoformat()
        log_dir = os.path.join(os.path.dirname(__file__), "log")
        os.makedirs(log_dir, exist_ok=True)
        log_path = os.path.join(log_dir, "debug.log")
        log_entry = f"[{timestamp}] IP={ip} MSG={msg}\n"
        with open(log_path, "a") as f:
            f.write(log_entry)
        if os.getenv("DEBUG", "0") in ("1", "true", "True"):
            print(f"[CLIENT-DEBUG] {log_entry.strip()}")
        return {"status": "ok"}
    except Exception as e:
        # Enhanced error logging
        import sys
        import traceback
        error_log_dir = os.path.join(os.path.dirname(__file__), "log")
        os.makedirs(error_log_dir, exist_ok=True)
        error_log_path = os.path.join(error_log_dir, "debug-errors.log")
        tb = traceback.format_exc()
        try:
            req_body = await request.body()
        except Exception:
            req_body = b"<failed to read body>"
        error_entry = (
            f"[{datetime.utcnow().isoformat()}] /log-client ERROR: {type(e).__name__}: {e}\n"
            f"Request IP: {getattr(request.client, 'host', None)}\n"
            f"Request body: {req_body}\n"
            f"Traceback:\n{tb}\n"
        )
        try:
            with open(error_log_path, "a") as ef:
                ef.write(error_entry)
        except Exception as ef_exc:
            print(f"[CLIENT-DEBUG-ERROR] Failed to write error log: {ef_exc}", file=sys.stderr)
        print(error_entry, file=sys.stderr)
        return {"status": "error", "detail": str(e)}

@app.get("/", response_class=HTMLResponse)
def serve_index():
    with open("static/index.html") as f:
        return f.read()

@app.get("/me", response_class=HTMLResponse)
def serve_me():
    with open("static/index.html") as f:
        return f.read()

@app.get("/admin/stats")
def admin_stats(request: Request, db: Session = Depends(get_db)):
    from sqlmodel import select
    users = db.exec(select(User)).all()
    users_count = len(users)
    total_quota = db.exec(select(UserQuota)).all()
    total_quota_sum = sum(q.storage_bytes for q in total_quota)
    violations_log = 0
    try:
        with open("log.txt") as f:
            violations_log = sum(1 for _ in f)
    except FileNotFoundError:
        pass

    secret = request.headers.get("x-admin-secret")
    if secret != ADMIN_SECRET:
        raise HTTPException(status_code=403, detail="Forbidden")

    return {
        "total_users": users_count,
        "total_quota_mb": round(total_quota_sum / (1024 * 1024), 2),
        "violation_log_entries": violations_log
    }

@app.get("/status")
def status():
    return {"status": "ok"}

@app.get("/debug")
def debug(request: Request):
    return {
        "ip": request.client.host,
        "headers": dict(request.headers),
    }

MAX_QUOTA_BYTES = 100 * 1024 * 1024

# Delete account endpoint has been moved to account_router.py

@app.delete("/uploads/{uid}/{filename}")
def delete_file(uid: str, filename: str, request: Request, db: Session = Depends(get_db)):
    user = get_user_by_uid(uid)
    if not user:
        raise HTTPException(status_code=403, detail="Invalid user ID")

    ip = request.client.host
    if user.ip != ip:
        raise HTTPException(status_code=403, detail="Device/IP mismatch")

    user_dir = os.path.join('data', user.username)
    target_path = os.path.join(user_dir, filename)
    # Prevent path traversal attacks
    real_target_path = os.path.realpath(target_path)
    real_user_dir = os.path.realpath(user_dir)
    if not real_target_path.startswith(real_user_dir + os.sep):
        raise HTTPException(status_code=403, detail="Invalid path")
    if not os.path.isfile(real_target_path):
        raise HTTPException(status_code=404, detail="File not found")

    os.remove(real_target_path)
    log_violation("DELETE", ip, uid, f"Deleted {filename}")
    subprocess.run(["/root/scripts/refresh_user_playlist.sh", user.username])

    try:
        actual_bytes = int(subprocess.check_output(["du", "-sb", user_dir]).split()[0])
        q = db.get(UserQuota, uid)
        if q:
            q.storage_bytes = actual_bytes
            db.add(q)
            db.commit()
    except Exception as e:
        log_violation("QUOTA", ip, uid, f"Quota update after delete failed: {e}")

    return {"status": "deleted"}

@app.get("/confirm/{uid}")
def confirm_user(uid: str, request: Request):
    ip = request.client.host
    user = get_user_by_uid(uid)
    if not user or user.ip != ip:
        raise HTTPException(status_code=403, detail="Unauthorized")
    return {"username": user.username, "email": user.email}

@app.get("/me/{uid}")
def get_me(uid: str, request: Request, db: Session = Depends(get_db)):
    print(f"[DEBUG] GET /me/{uid} - Client IP: {request.client.host}")
    try:
        # Get user info
        user = get_user_by_uid(uid)
        if not user:
            print(f"[ERROR] User with UID {uid} not found")
            raise HTTPException(status_code=403, detail="User not found")
            
        if user.ip != request.client.host:
            print(f"[ERROR] IP mismatch for UID {uid}: {request.client.host} != {user.ip}")
            raise HTTPException(status_code=403, detail="IP address mismatch")

        # Get all upload logs for this user
        upload_logs = db.exec(
            select(UploadLog)
            .where(UploadLog.uid == uid)
            .order_by(UploadLog.created_at.desc())
        ).all()
        print(f"[DEBUG] Found {len(upload_logs)} upload logs for UID {uid}")
        
        # Build file list from database records
        files = []
        for log in upload_logs:
            if log.filename and log.processed_filename:
                # The actual filename on disk might have the log ID prepended
                stored_filename = f"{log.id}_{log.processed_filename}"
                files.append({
                    "name": stored_filename,
                    "original_name": log.filename,
                    "size": log.size_bytes
                })
                print(f"[DEBUG] Added file from DB: {log.filename} (stored as {stored_filename}, {log.size_bytes} bytes)")
        
        # Get quota info
        q = db.get(UserQuota, uid)
        quota_mb = round(q.storage_bytes / (1024 * 1024), 2) if q else 0
        print(f"[DEBUG] Quota for UID {uid}: {quota_mb} MB")

        response_data = {
            "files": files,
            "quota": quota_mb
        }
        print(f"[DEBUG] Returning {len(files)} files and quota info")
        return response_data
        
    except Exception as e:
        print(f"[ERROR] Error in /me/{uid} endpoint: {str(e)}", exc_info=True)
        raise