#!/usr/bin/env python3
import os
import subprocess
import time
from watchdog.observers import Observer
from watchdog.events import FileSystemEventHandler

WATCH_DIR = "/data"  # Mount your host Books folder here
DEBUG = os.getenv("DEBUG", "false").lower() == "true"
MERGE_ALL = os.getenv("MERGE_ALL", "true").lower() == "true"

class NewBookHandler(FileSystemEventHandler):
    def __init__(self):
        super().__init__()
        self.seen_dirs = set()  # Track processed directories

    def on_created(self, event):
        if event.is_directory:
            self.process_new_dir(event.src_path)

    def on_moved(self, event):
        if event.is_directory:
            self.process_new_dir(event.dest_path)

    def process_new_dir(self, path):
        # Avoid duplicate processing
        if path in self.seen_dirs:
            return
        self.seen_dirs.add(path)

        # Short delay to allow files to finish copying
        time.sleep(2)

        try:
            files = os.listdir(path)
        except FileNotFoundError:
            return  # directory may have been removed

        m4b_files = [f for f in files if f.lower().endswith(".m4b") and not f.startswith("._")]
        if not m4b_files:
            if DEBUG:
                print(f"⚠️ Skipping {path} (no .m4b files detected)")
            return

        # Skip if only 1 file and MERGE_ALL is enabled
        if MERGE_ALL and len(m4b_files) == 1:
            if DEBUG:
                print(f"⏭️ Skipping {path} (only 1 .m4b file, nothing to merge)")
            return

        book_name = os.path.basename(path)
        print(f"📕 New book detected: {book_name} at {path}")
        print("Contains .m4b files:")
        for f in m4b_files:
            print("  ", f)

        # Run your main.py script
        try:
            cmd = ["python3", "main.py", "-da", path]
            if MERGE_ALL:
                cmd.append("--all")  # pass flag to main.py
            subprocess.run(cmd, check=True)
            print(f"✅ Finished processing {book_name}")
        except subprocess.CalledProcessError as e:
            print(f"❌ Error processing {book_name}: {e}")

if __name__ == "__main__":
    observer = Observer()
    event_handler = NewBookHandler()
    observer.schedule(event_handler, WATCH_DIR, recursive=True)
    observer.start()
    print(f"👀 Watching for new book folders in {WATCH_DIR} ...")

    # --- Startup scan: just print existing folders if DEBUG is enabled ---
    if DEBUG:
        for root, dirs, files in os.walk(WATCH_DIR):
            m4b_files = [f for f in files if f.lower().endswith(".m4b") and not f.startswith("._")]
            if m4b_files:
                print(f"📁 Existing book folder detected (startup scan): {root}")
                for f in m4b_files:
                    print("  ", f)

    try:
        while True:
            time.sleep(1)
    except KeyboardInterrupt:
        observer.stop()
    observer.join()