#!/usr/bin/env python3
"""
Improved Python startup script for TimeTracker
This script ensures proper database initialization order and handles errors gracefully
"""

import os
import sys
import time
import subprocess
import traceback
import psycopg2
from urllib.parse import urlparse

def wait_for_database():
    """Wait for database to be ready with proper connection testing"""
    print("Waiting for database to be ready...")
    
    # Get database URL from environment
    db_url = os.getenv('DATABASE_URL', 'postgresql+psycopg2://timetracker:timetracker@db:5432/timetracker')

    # If using SQLite, ensure the database directory exists and return immediately
    if db_url.startswith('sqlite:'):
        try:
            # Normalize file path from URL
            db_path = None
            prefix_four = 'sqlite:////'
            prefix_three = 'sqlite:///'
            prefix_mem = 'sqlite://'
            if db_url.startswith(prefix_four):
                db_path = '/' + db_url[len(prefix_four):]
            elif db_url.startswith(prefix_three):
                # Relative inside container; keep as-is
                db_path = db_url[len(prefix_three):]
                # If it's a relative path, make sure directory exists
                if not db_path.startswith('/'):
                    db_path = '/' + db_path
            elif db_url.startswith(prefix_mem):
                # Could be sqlite:///:memory:
                if db_url.endswith(':memory:'):
                    return True
                # Fallback: strip scheme
                db_path = db_url[len(prefix_mem):]

            if db_path:
                import os as _os
                import sqlite3 as _sqlite3
                dir_path = _os.path.dirname(db_path)
                if dir_path:
                    _os.makedirs(dir_path, exist_ok=True)
                # Try to open the database to ensure writability
                conn = _sqlite3.connect(db_path)
                conn.close()
            return True
        except Exception as e:
            print(f"SQLite path/setup check failed: {e}")
            return False
    
    # Parse the URL to get connection details (PostgreSQL)
    if db_url.startswith('postgresql+psycopg2://'):
        db_url = db_url.replace('postgresql+psycopg2://', '')
    
    # Extract host, port, database, user, password
    if '@' in db_url:
        auth_part, rest = db_url.split('@', 1)
        user, password = auth_part.split(':', 1)
        if ':' in rest:
            host_port, database = rest.rsplit('/', 1)
            if ':' in host_port:
                host, port = host_port.split(':', 1)
            else:
                host, port = host_port, '5432'
        else:
            host, port, database = rest, '5432', 'timetracker'
    else:
        host, port, database, user, password = 'db', '5432', 'timetracker', 'timetracker', 'timetracker'
    
    max_attempts = 30
    attempt = 0
    
    while attempt < max_attempts:
        try:
            print(f"Attempting database connection to {host}:{port}/{database} as {user}...")
            conn = psycopg2.connect(
                host=host,
                port=port,
                database=database,
                user=user,
                password=password,
                connect_timeout=5
            )
            conn.close()
            print("✓ Database connection successful!")
            return True
        except Exception as e:
            attempt += 1
            print(f"✗ Database connection attempt {attempt}/{max_attempts} failed: {e}")
            if attempt < max_attempts:
                print("Waiting 2 seconds before retry...")
                time.sleep(2)
    
    print("✗ Failed to connect to database after all attempts")
    return False

def run_script(script_path, description):
    """Run a Python script with proper error handling"""
    print(f"Running {description}...")
    try:
        result = subprocess.run(
            [sys.executable, script_path], 
            check=True,
            capture_output=True,
            text=True
        )
        print(f"✓ {description} completed successfully")
        if result.stdout:
            print(f"Output: {result.stdout}")
        return True
    except subprocess.CalledProcessError as e:
        print(f"✗ {description} failed with exit code {e.returncode}")
        if e.stdout:
            print(f"stdout: {e.stdout}")
        if e.stderr:
            print(f"stderr: {e.stderr}")
        return False
    except Exception as e:
        print(f"✗ Unexpected error running {description}: {e}")
        traceback.print_exc()
        return False

def display_network_info():
    """Display network information for debugging"""
    print("=== Network Information ===")
    try:
        print(f"Hostname: {os.uname().nodename}")
    except:
        print("Hostname: N/A (Windows)")
    
    try:
        import socket
        hostname = socket.gethostname()
        local_ip = socket.gethostbyname(hostname)
        print(f"Local IP: {local_ip}")
    except:
        print("Local IP: N/A")
    
    print(f"Environment: {os.environ.get('FLASK_APP', 'N/A')}")
    print(f"Working Directory: {os.getcwd()}")
    print("==========================")

def main():
    print("=== Starting TimeTracker (Improved Python Mode) ===")
    
    # Display network information for debugging
    display_network_info()
    
    # Set environment
    os.environ['FLASK_APP'] = 'app'
    os.chdir('/app')
    
    # Wait for database
    if not wait_for_database():
        print("Database is not available, exiting...")
        sys.exit(1)
    
    # Run enhanced database initialization and migration (strict schema verification and auto-fix)
    if not run_script('/app/docker/init-database-enhanced.py', 'Enhanced database initialization and migration'):
        print("Enhanced database initialization failed, exiting...")
        sys.exit(1)
    
    print("✓ Database initialization and migration completed successfully")
    
    # Ensure default settings and admin user exist (idempotent)
    try:
        print("Ensuring default settings and admin user exist (flask init_db)...")
        result = subprocess.run(
            ['flask', 'init_db'],
            check=True,
            capture_output=True,
            text=True
        )
        if result.stdout:
            print(result.stdout.strip())
        if result.stderr:
            print(result.stderr.strip())
    except subprocess.CalledProcessError as e:
        print(f"Warning: flask init_db failed (continuing): exit {e.returncode}")
        if e.stdout:
            print(f"stdout: {e.stdout.strip()}")
        if e.stderr:
            print(f"stderr: {e.stderr.strip()}")
    except Exception as e:
        print(f"Warning: could not execute flask init_db: {e}")

    print("Starting application...")
    # Start gunicorn with access logs
    os.execv('/usr/local/bin/gunicorn', [
        'gunicorn',
        '--bind', '0.0.0.0:8080',
        '--worker-class', 'eventlet',
        '--workers', '1',
        '--timeout', '120',
        '--access-logfile', '-',
        '--error-logfile', '-',
        '--log-level', 'info',
        'app:create_app()'
    ])

if __name__ == '__main__':
    main()