# CoderAI - OpenAI-compatible API server
# Copyright (C) 2026 Stefy Lanza <stefy@nexlab.net>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <https://www.gnu.org/licenses/>.

"""
FastAPI application module for codai API.
Contains the FastAPI app initialization, lifespan, and core endpoints.
"""

import logging
import os
from contextlib import asynccontextmanager
from typing import List

from fastapi import FastAPI, HTTPException, Request
from fastapi.responses import FileResponse, JSONResponse

logger = logging.getLogger(__name__)

# Import from codai modules
from codai.pydantic.textrequest import ModelList
from codai.models.manager import model_manager, multi_model_manager

# Import global state functions - re-export for backward compatibility
from codai.api.state import (
    get_load_mode,
    set_load_mode,
    get_global_args,
    set_global_args,
    set_global_file_path,
    get_global_debug,
    set_global_debug,
)

# Aliases for backward compatibility
global_debug = False
global_file_path = None


def set_global_debug_wrapper(debug: bool):
    """Set the global debug flag."""
    global global_debug
    global_debug = debug
    set_global_debug(debug)


def set_global_file_path_wrapper(path: str):
    """Set the global file path."""
    global global_file_path
    global_file_path = path
    set_global_file_path(path)


@asynccontextmanager
async def lifespan(app: FastAPI):
    """Lifespan context manager for startup/shutdown."""
    # Startup
    yield
    # Shutdown
    multi_model_manager.cleanup()
    model_manager.cleanup()
    # Stop whisper-server if running
    if multi_model_manager.whisper_server:
        multi_model_manager.whisper_server.stop()


# Create the FastAPI app
app = FastAPI(
    title="OpenAI-Compatible API",
    description="OpenAI-compatible API supporting NVIDIA (CUDA) and Vulkan backends",
    version="2.0.0",
    lifespan=lifespan,
)


# Import routers from submodules
from codai.api.transcriptions import router as transcriptions_router
from codai.api.images import router as images_router
from codai.api.tts import router as tts_router
from codai.api.text import router as text_router
from codai.api.video import router as video_router
from codai.api.audio_gen import router as audio_gen_router
from codai.api.audio_stems import router as audio_stems_router
from codai.api.audio_clean import router as audio_clean_router
from codai.api.embeddings import router as embeddings_router
from codai.api.pipelines import router as pipelines_router
from codai.api.custom_pipelines import router as custom_pipelines_router
from codai.api.voice_clone import router as voice_clone_router
from codai.api.voice_convert import router as voice_convert_router
from codai.api.faceswap import router as faceswap_router
from codai.api.characters import router as characters_router
from codai.admin.routes import router as admin_router

# Import and add middleware
from codai.api.log import log_requests
from codai.api.ratelimit import RateLimitMiddleware
app.middleware("http")(log_requests)
app.add_middleware(RateLimitMiddleware)

# Mount static files for admin dashboard
from fastapi.staticfiles import StaticFiles
from pathlib import Path
admin_static_dir = Path(__file__).parent.parent / "admin" / "static"
if admin_static_dir.exists():
    app.mount("/static/admin", StaticFiles(directory=str(admin_static_dir)), name="admin_static")

# Include routers from submodules
app.include_router(transcriptions_router)
app.include_router(images_router)
app.include_router(tts_router)
app.include_router(text_router)
app.include_router(video_router)
app.include_router(audio_gen_router)
app.include_router(audio_stems_router)
app.include_router(audio_clean_router)
app.include_router(embeddings_router)
app.include_router(pipelines_router)
app.include_router(custom_pipelines_router)
app.include_router(voice_clone_router)
app.include_router(voice_convert_router)
app.include_router(faceswap_router)
app.include_router(characters_router)
app.include_router(admin_router)


@app.exception_handler(401)
async def unauthorized_redirect(request: Request, exc: HTTPException):
    """Redirect browser clients to login page on 401; return JSON for API clients."""
    accept = request.headers.get("accept", "")
    if "text/html" in accept:
        from fastapi.responses import RedirectResponse
        return RedirectResponse(url="/login", status_code=302)
    return JSONResponse(status_code=401, content={"detail": exc.detail})


@app.get("/v1/models", response_model=ModelList)
async def list_models():
    """List available models."""
    models = multi_model_manager.list_models()
    return ModelList(data=models)


@app.get("/v1/files/{filename}")
async def get_file(filename: str):
    """Serve uploaded/generated files."""
    if not global_file_path:
        raise HTTPException(status_code=404, detail="File not found")
    # Prevent path traversal: resolve to real paths and confirm the result
    # stays inside the configured directory.
    safe_base = os.path.realpath(global_file_path)
    candidate = os.path.realpath(os.path.join(global_file_path, filename))
    if not (candidate == safe_base or candidate.startswith(safe_base + os.sep)):
        raise HTTPException(status_code=403, detail="Access denied")
    if not os.path.isfile(candidate):
        raise HTTPException(status_code=404, detail="File not found")
    return FileResponse(candidate)