"""
EL HELAL Studio — Web Backend (FastAPI)
Integrated with Auto-Cleanup and Custom Cropping
"""

from fastapi import FastAPI, UploadFile, File, Form, BackgroundTasks
from fastapi.responses import JSONResponse, FileResponse
from fastapi.staticfiles import StaticFiles
from fastapi.middleware.cors import CORSMiddleware
from contextlib import asynccontextmanager
import uvicorn
import shutil
import os
import json
import uuid
from pathlib import Path
from PIL import Image
import threading
import sys
import asyncio
import time

# Add core directory to python path
sys.path.append(os.path.abspath(os.path.join(os.path.dirname(__file__), '..', 'core')))

# Import existing tools
import crop
import process_images
import color_steal
import retouch
from layout_engine import generate_layout, load_settings

# Setup Directories
WEB_DIR = Path(os.path.dirname(__file__)) / "web_storage"
ROOT_DIR = Path(os.path.dirname(__file__)).parent
STORAGE_DIR = ROOT_DIR / "storage"

UPLOAD_DIR = STORAGE_DIR / "uploads"
PROCESSED_DIR = STORAGE_DIR / "processed"
RESULT_DIR = STORAGE_DIR / "results"

for d in [UPLOAD_DIR, PROCESSED_DIR, RESULT_DIR]:
    d.mkdir(parents=True, exist_ok=True)

# Global Model State
models = {
    "model": None,
    "transform": None,
    "luts": color_steal.load_trained_curves(),
    "ready": False
}

def warm_up_ai():
    print("AI Model: Loading in background...")
    try:
        models["model"], _ = process_images.setup_model()
        models["transform"] = process_images.get_transform()
        models["ready"] = True
        print("AI Model: READY")
    except Exception as e:
        print(f"AI Model: FAILED to load - {e}")

async def cleanup_task():
    """Background task to delete files older than 24 hours."""
    while True:
        print("Cleanup: Checking for old files...")
        now = time.time()
        count = 0
        for folder in [UPLOAD_DIR, PROCESSED_DIR, RESULT_DIR]:
            for path in folder.glob("*"):
                if path.is_file() and (now - path.stat().st_mtime) > 86400: # 24 hours
                    path.unlink()
                    count += 1
        if count > 0: print(f"Cleanup: Removed {count} old files.")
        await asyncio.sleep(3600) # Run every hour

@asynccontextmanager
async def lifespan(app: FastAPI):
    # Startup
    threading.Thread(target=warm_up_ai, daemon=True).start()
    asyncio.create_task(cleanup_task())
    yield
    # Shutdown
    pass

app = FastAPI(title="EL HELAL Studio API", lifespan=lifespan)

app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_methods=["*"],
    allow_headers=["*"],
)

# ── API Endpoints ──

@app.get("/")
async def read_index():
    return FileResponse(WEB_DIR / "index.html")

@app.get("/status")
async def get_status():
    return {"ai_ready": models["ready"]}

@app.post("/upload")
async def upload_image(file: UploadFile = File(...)):
    file_id = str(uuid.uuid4())
    ext = Path(file.filename).suffix
    file_path = UPLOAD_DIR / f"{file_id}{ext}"
    
    with file_path.open("wb") as buffer:
        shutil.copyfileobj(file.file, buffer)
    
    with Image.open(file_path) as img:
        from PIL import ImageOps
        # FIX: Handle EXIF orientation (rotation)
        img = ImageOps.exif_transpose(img)

        # Get original dimensions after transposition for the web cropper
        width, height = img.size

        # Create a faster, smaller thumbnail for the UI (200x200 is plenty for the 72px grid)
        img.thumbnail((200, 200), Image.BILINEAR)
        thumb_path = UPLOAD_DIR / f"{file_id}_thumb.jpg"
        if img.mode in ("RGBA", "LA"):
            bg = Image.new("RGB", img.size, (255, 255, 255))
            bg.paste(img, mask=img.split()[-1])
            bg.save(thumb_path, "JPEG", quality=60)
        else:
            img.convert("RGB").save(thumb_path, "JPEG", quality=60)
    return {
        "id": file_id, 
        "filename": file.filename, 
        "thumb_url": f"/static/uploads/{file_id}_thumb.jpg",
        "width": width,
        "height": height
    }

@app.post("/process/{file_id}")
async def process_image(
    file_id: str, 
    name: str = Form(""), 
    id_number: str = Form(""),
    # Steps toggles
    do_rmbg: bool = Form(True),
    do_color: bool = Form(True),
    do_retouch: bool = Form(True),
    do_crop: bool = Form(True),
    # Branding toggles
    add_studio_name: bool = Form(True),
    add_logo: bool = Form(True),
    add_date: bool = Form(True),
    # Optional manual crop coordinates
    x1: int = Form(None), 
    y1: int = Form(None), 
    x2: int = Form(None), 
    y2: int = Form(None)
):
    if not models["ready"]:
        return JSONResponse(status_code=503, content={"error": "AI Model not ready"})
    
    files = list(UPLOAD_DIR.glob(f"{file_id}.*"))
    if not files: return JSONResponse(status_code=404, content={"error": "File not found"})
    orig_path = files[0]
    
    try:
        temp_crop = PROCESSED_DIR / f"{file_id}_processed_crop.jpg"
        
        # 1. CROP (Manual, Auto, or Skip)
        if x1 is not None and y1 is not None:
            print(f"Pipeline: Applying manual crop for {file_id} | Rect: ({x1}, {y1}, {x2}, {y2})")
            rect = (x1, y1, x2, y2)
            crop.apply_custom_crop(str(orig_path), str(temp_crop), rect)
            cropped_img = Image.open(temp_crop)
        elif do_crop:
            print(f"Pipeline: Applying auto crop for {file_id}...")
            crop.crop_to_4x6_opencv(str(orig_path), str(temp_crop))
            cropped_img = Image.open(temp_crop)
        else:
            print(f"Pipeline: Skipping crop for {file_id}")
            cropped_img = Image.open(orig_path)
        
        # 2. BACKGROUND REMOVAL
        if do_rmbg:
            print(f"Pipeline: Removing background for {file_id}...")
            processed_img = process_images.remove_background(models["model"], cropped_img, models["transform"])
            print(f"Pipeline: BG Removal Done. Image Mode: {processed_img.mode}")
        else:
            print(f"Pipeline: Skipping background removal for {file_id}")
            processed_img = cropped_img
        
        # 3. COLOR GRADING
        if do_color and models["luts"]:
            print(f"Pipeline: Applying color grading for {file_id}...")
            graded_img = color_steal.apply_to_image(models["luts"], processed_img)
            print(f"Pipeline: Color Grading Done. Image Mode: {graded_img.mode}")
        else:
            print(f"Pipeline: Skipping color grading for {file_id}")
            graded_img = processed_img
            
        # 4. RETOUCH
        current_settings = load_settings()
        # Retouch happens if BOTH the UI checkbox is checked AND it's enabled in global settings
        if do_retouch and current_settings.get("retouch", {}).get("enabled", False):
            retouch_cfg = current_settings["retouch"]
            print(f"Pipeline: Retouching face for {file_id} (Sensitivity: {retouch_cfg.get('sensitivity', 3.0)})")
            final_processed, count = retouch.retouch_image_pil(
                graded_img, 
                sensitivity=retouch_cfg.get("sensitivity", 3.0),
                tone_smoothing=retouch_cfg.get("tone_smoothing", 0.6)
            )
            print(f"Pipeline: Retouch Done. Blemishes: {count}. Image Mode: {final_processed.mode}")
        else:
            print(f"Pipeline: Retouching skipped for {file_id}")
            final_processed = graded_img
            
        print(f"Pipeline: Generating final layout for {file_id}...")
        final_layout = generate_layout(
            final_processed, name, id_number,
            add_studio_name=add_studio_name,
            add_logo=add_logo,
            add_date=add_date
        )

        result_path = RESULT_DIR / f"{file_id}_layout.jpg"
        final_layout.save(result_path, "JPEG", quality=95, dpi=(300, 300))

        # 5. Generate a lightweight WEB PREVIEW (max 900px width) for the UI
        preview_path = RESULT_DIR / f"{file_id}_preview.jpg"
        pw, ph = final_layout.size
        p_scale = 900 / pw if pw > 900 else 1.0
        if p_scale < 1.0:
            preview_img = final_layout.resize((int(pw * p_scale), int(ph * p_scale)), Image.BILINEAR)
            preview_img.save(preview_path, "JPEG", quality=70)
        else:
            final_layout.save(preview_path, "JPEG", quality=70)

        if temp_crop.exists(): temp_crop.unlink()

        return {
            "id": file_id,
            "result_url": f"/static/results/{file_id}_layout.jpg",
            "preview_url": f"/static/results/{file_id}_preview.jpg"
        }
    except Exception as e:
        import traceback
        traceback.print_exc()
        return JSONResponse(status_code=500, content={"error": str(e)})

@app.post("/clear-all")
async def clear_all():
    """Manually clear all uploaded and processed files."""
    count = 0
    try:
        for folder in [UPLOAD_DIR, PROCESSED_DIR, RESULT_DIR]:
            for path in folder.glob("*"):
                if path.is_file() and not path.name.endswith(".gitkeep"):
                    path.unlink()
                    count += 1
        return {"status": "success", "removed_count": count}
    except Exception as e:
        return JSONResponse(status_code=500, content={"error": f"Failed to clear storage: {str(e)}"})

# ── Settings API ──
SETTINGS_PATH = ROOT_DIR / "config" / "settings.json"

@app.get("/settings")
async def get_settings():
    """Return current settings.json contents."""
    try:
        if SETTINGS_PATH.exists():
            with open(SETTINGS_PATH, "r") as f:
                return json.load(f)
        return {}
    except Exception as e:
        return JSONResponse(status_code=500, content={"error": str(e)})

@app.post("/settings")
async def update_settings(data: dict):
    """Merge incoming settings into settings.json (partial update)."""
    try:
        current = {}
        if SETTINGS_PATH.exists():
            with open(SETTINGS_PATH, "r") as f:
                current = json.load(f)
        # Deep merge one level
        for key, val in data.items():
            if key in current and isinstance(val, dict) and isinstance(current[key], dict):
                current[key].update(val)
            else:
                current[key] = val
        SETTINGS_PATH.parent.mkdir(parents=True, exist_ok=True)
        with open(SETTINGS_PATH, "w") as f:
            json.dump(current, f, indent=4, ensure_ascii=False)
        return {"status": "success"}
    except Exception as e:
        return JSONResponse(status_code=500, content={"error": str(e)})

app.mount("/static", StaticFiles(directory=str(STORAGE_DIR)), name="static")

if __name__ == "__main__":
    # Hugging Face Spaces uses port 7860 by default
    port = int(os.environ.get("PORT", 7860))
    uvicorn.run(app, host="0.0.0.0", port=port)