import os
import sys
import subprocess
import yaml
import shutil

# Constants
SCRIPTS_DIR = "/scripts"
DEFAULTS_DIR = "/app/defaults"
CONFIG_PATH = os.path.join(SCRIPTS_DIR, "config.yaml")
CRONTAB_PATH = "/app/generated_crontab"

def initialize_volume_if_empty():
    """Copies default files to /scripts if config.yaml is missing."""
    if not os.path.exists(CONFIG_PATH):
        print("---------------------------------")
        print("No config found in volume. Initializing with defaults...")
        
        # Ensure directory exists
        os.makedirs(SCRIPTS_DIR, exist_ok=True)
        
        # Copy all files from defaults to scripts
        if os.path.exists(DEFAULTS_DIR):
            for filename in os.listdir(DEFAULTS_DIR):
                src = os.path.join(DEFAULTS_DIR, filename)
                dst = os.path.join(SCRIPTS_DIR, filename)
                if os.path.isfile(src):
                    shutil.copy2(src, dst)
                    print(f"  -> Created: {filename}")
        print("Initialization complete.")
        print("---------------------------------")
    else:
        print(f"Found existing config at {CONFIG_PATH}. Using it.")

def install_dependencies(deps):
    if not deps:
        return
    print(f"Installing {len(deps)} dependencies...")
    subprocess.check_call([sys.executable, "-m", "pip", "install", "--no-cache-dir"] + deps)

def generate_crontab(jobs):
    print(f"Scheduling {len(jobs)} jobs...")
    lines = []
    for job in jobs:
        schedule = job['schedule']
        script = job['script']
        # Use -u for unbuffered output
        command = f"python3 -u {SCRIPTS_DIR}/{script}"
        lines.append(f"{schedule} {command}")
        print(f"  -> Loaded: {script} [{schedule}]")

    with open(CRONTAB_PATH, "w") as f:
        f.write("\n".join(lines) + "\n")

def main():
    # 1. Initialize Volume (The new feature)
    initialize_volume_if_empty()

    # 2. Read Config
    if not os.path.exists(CONFIG_PATH):
        print(f"Error: {CONFIG_PATH} still not found after initialization.")
        sys.exit(1)

    with open(CONFIG_PATH, "r") as f:
        config = yaml.safe_load(f)

    # 3. Setup Environment
    install_dependencies(config.get("dependencies", []))
    generate_crontab(config.get("jobs", []))

    # 4. Start Supercronic
    print("Starting Scheduler...")
    print("--------------------------------------------")
    sys.stdout.flush()

    # Wir starten Supercronic und leiten stderr (wo Logs sind) an stdout weiter
    # und pipen das Ganze in unseren log_formatter.py
    cmd = f"supercronic {CRONTAB_PATH} 2>&1 | python3 -u /app/log_formatter.py"
    
    # shell=True ist hier notwendig für die Pipe "|"
    subprocess.call(cmd, shell=True)

if __name__ == "__main__":
    main()