#!/usr/bin/env python3
"""
Database Migration Status Checker
Checks what migration steps have been completed and what's missing
"""
import sys
import os
from sqlalchemy import create_engine, text, inspect
from sqlalchemy.orm import sessionmaker
from dotenv import load_dotenv

# Load environment variables
load_dotenv()

# Get database URL from environment or use provided one
DATABASE_URL = os.getenv('DATABASE_URL')

if not DATABASE_URL:
    print("ERROR: DATABASE_URL not found in environment")
    sys.exit(1)

# Create database connection
engine = create_engine(DATABASE_URL)
Session = sessionmaker(bind=engine)
db = Session()
inspector = inspect(engine)

print("=" * 80)
print("DATABASE MIGRATION STATUS CHECKER")
print("=" * 80)
print(f"\nConnected to: {DATABASE_URL.split('@')[1] if '@' in DATABASE_URL else 'database'}")
print()

# Colors for output
class Colors:
    GREEN = '\033[92m'
    RED = '\033[91m'
    YELLOW = '\033[93m'
    BLUE = '\033[94m'
    END = '\033[0m'

def check_mark(exists):
    return f"{Colors.GREEN}✓{Colors.END}" if exists else f"{Colors.RED}✗{Colors.END}"

def warning(exists):
    return f"{Colors.YELLOW}⚠{Colors.END}" if exists else f"{Colors.GREEN}✓{Colors.END}"

issues = []
warnings = []

# ============================================================
# Check 1: Does roles table exist?
# ============================================================
print(f"{Colors.BLUE}[1] Checking if 'roles' table exists...{Colors.END}")
roles_table_exists = 'roles' in inspector.get_table_names()
print(f"   {check_mark(roles_table_exists)} roles table exists")

if not roles_table_exists:
    issues.append("❌ MISSING: 'roles' table - run migration 006_add_dynamic_roles.sql")
    print(f"\n{Colors.RED}ISSUE: roles table not found!{Colors.END}")
    print(f"   Action: Run 'psql $DATABASE_URL -f migrations/006_add_dynamic_roles.sql'")

# ============================================================
# Check 2: Does users table have role_id column?
# ============================================================
print(f"\n{Colors.BLUE}[2] Checking if 'users' table has 'role_id' column...{Colors.END}")
users_columns = [col['name'] for col in inspector.get_columns('users')]
users_has_role_id = 'role_id' in users_columns
print(f"   {check_mark(users_has_role_id)} users.role_id column exists")

if not users_has_role_id:
    issues.append("❌ MISSING: 'users.role_id' column - run migration 006_add_dynamic_roles.sql")
    print(f"\n{Colors.RED}ISSUE: users.role_id column not found!{Colors.END}")
    print(f"   Action: Run 'psql $DATABASE_URL -f migrations/006_add_dynamic_roles.sql'")

# ============================================================
# Check 3: Does role_permissions table have role_id column?
# ============================================================
print(f"\n{Colors.BLUE}[3] Checking if 'role_permissions' table has 'role_id' column...{Colors.END}")
rp_columns = [col['name'] for col in inspector.get_columns('role_permissions')]
rp_has_role_id = 'role_id' in rp_columns
print(f"   {check_mark(rp_has_role_id)} role_permissions.role_id column exists")

if not rp_has_role_id:
    issues.append("❌ MISSING: 'role_permissions.role_id' column - run migration 006_add_dynamic_roles.sql")
    print(f"\n{Colors.RED}ISSUE: role_permissions.role_id column not found!{Colors.END}")
    print(f"   Action: Run 'psql $DATABASE_URL -f migrations/006_add_dynamic_roles.sql'")

# ============================================================
# Check 4: Are system roles seeded?
# ============================================================
if roles_table_exists:
    print(f"\n{Colors.BLUE}[4] Checking if system roles are seeded...{Colors.END}")
    result = db.execute(text("SELECT COUNT(*) as count FROM roles WHERE is_system_role = true"))
    system_roles_count = result.scalar()
    print(f"   System roles found: {system_roles_count}")

    if system_roles_count == 0:
        issues.append("❌ MISSING: System roles not seeded - run roles_seed.py")
        print(f"   {Colors.RED}✗ No system roles found!{Colors.END}")
        print(f"   Action: Run 'python3 roles_seed.py'")
    elif system_roles_count < 5:
        warnings.append(f"⚠️  WARNING: Expected 5 system roles, found {system_roles_count}")
        print(f"   {Colors.YELLOW}⚠{Colors.END} Expected 5 roles, found {system_roles_count}")
        print(f"   Action: Run 'python3 roles_seed.py' to ensure all roles exist")
    else:
        print(f"   {Colors.GREEN}✓{Colors.END} All system roles seeded")

    # Show which roles exist
    result = db.execute(text("SELECT code, name FROM roles WHERE is_system_role = true ORDER BY code"))
    existing_roles = result.fetchall()
    if existing_roles:
        print(f"\n   Existing roles:")
        for role in existing_roles:
            print(f"     - {role[0]}: {role[1]}")

# ============================================================
# Check 5: Are users migrated to dynamic roles?
# ============================================================
if users_has_role_id and roles_table_exists:
    print(f"\n{Colors.BLUE}[5] Checking if users are migrated to dynamic roles...{Colors.END}")

    # Count total users
    result = db.execute(text("SELECT COUNT(*) FROM users"))
    total_users = result.scalar()
    print(f"   Total users: {total_users}")

    # Count users with role_id set
    result = db.execute(text("SELECT COUNT(*) FROM users WHERE role_id IS NOT NULL"))
    migrated_users = result.scalar()
    print(f"   Migrated users (with role_id): {migrated_users}")

    # Count users without role_id
    unmigrated_users = total_users - migrated_users

    if unmigrated_users > 0:
        issues.append(f"❌ INCOMPLETE: {unmigrated_users} users not migrated to dynamic roles")
        print(f"   {Colors.RED}✗ {unmigrated_users} users still need migration!{Colors.END}")
        print(f"   Action: Run 'python3 migrate_users_to_dynamic_roles.py'")

        # Show sample unmigrated users
        result = db.execute(text("""
            SELECT email, role FROM users
            WHERE role_id IS NULL
            LIMIT 5
        """))
        unmigrated = result.fetchall()
        if unmigrated:
            print(f"\n   Sample unmigrated users:")
            for user in unmigrated:
                print(f"     - {user[0]} (role: {user[1]})")
    else:
        print(f"   {Colors.GREEN}✓{Colors.END} All users migrated to dynamic roles")

# ============================================================
# Check 6: Are role permissions migrated?
# ============================================================
if rp_has_role_id and roles_table_exists:
    print(f"\n{Colors.BLUE}[6] Checking if role permissions are migrated...{Colors.END}")

    # Count total role_permissions
    result = db.execute(text("SELECT COUNT(*) FROM role_permissions"))
    total_perms = result.scalar()
    print(f"   Total role_permissions: {total_perms}")

    # Count permissions with role_id set
    result = db.execute(text("SELECT COUNT(*) FROM role_permissions WHERE role_id IS NOT NULL"))
    migrated_perms = result.scalar()
    print(f"   Migrated permissions (with role_id): {migrated_perms}")

    unmigrated_perms = total_perms - migrated_perms

    if unmigrated_perms > 0:
        issues.append(f"❌ INCOMPLETE: {unmigrated_perms} permissions not migrated to dynamic roles")
        print(f"   {Colors.RED}✗ {unmigrated_perms} permissions still need migration!{Colors.END}")
        print(f"   Action: Run 'python3 migrate_role_permissions_to_dynamic_roles.py'")
    else:
        print(f"   {Colors.GREEN}✓{Colors.END} All permissions migrated to dynamic roles")

# ============================================================
# Check 7: Verify admin account
# ============================================================
print(f"\n{Colors.BLUE}[7] Checking admin account...{Colors.END}")
result = db.execute(text("""
    SELECT email, role, role_id
    FROM users
    WHERE email LIKE '%admin%' OR role = 'admin' OR role = 'superadmin'
    LIMIT 5
"""))
admin_users = result.fetchall()

if admin_users:
    print(f"   Found {len(admin_users)} admin/superadmin users:")
    for user in admin_users:
        role_id_status = "✓" if user[2] else "✗"
        print(f"     {role_id_status} {user[0]} (role: {user[1]}, role_id: {user[2] or 'NULL'})")
else:
    warnings.append("⚠️  WARNING: No admin users found")
    print(f"   {Colors.YELLOW}⚠{Colors.END} No admin users found in database")

# ============================================================
# Summary
# ============================================================
print("\n" + "=" * 80)
print("SUMMARY")
print("=" * 80)

if not issues and not warnings:
    print(f"\n{Colors.GREEN}✓ All migration steps completed successfully!{Colors.END}")
    print("\nNext steps:")
    print("  1. Deploy latest backend code")
    print("  2. Restart backend server")
    print("  3. Test /api/admin/users/export endpoint")
else:
    if issues:
        print(f"\n{Colors.RED}ISSUES FOUND ({len(issues)}):{Colors.END}")
        for i, issue in enumerate(issues, 1):
            print(f"  {i}. {issue}")

    if warnings:
        print(f"\n{Colors.YELLOW}WARNINGS ({len(warnings)}):{Colors.END}")
        for i, warning in enumerate(warnings, 1):
            print(f"  {i}. {warning}")

    print(f"\n{Colors.BLUE}RECOMMENDED ACTIONS:{Colors.END}")
    if not roles_table_exists or not users_has_role_id or not rp_has_role_id:
        print("  1. Run: psql $DATABASE_URL -f migrations/006_add_dynamic_roles.sql")
    if roles_table_exists and system_roles_count == 0:
        print("  2. Run: python3 roles_seed.py")
    if unmigrated_users > 0:
        print("  3. Run: python3 migrate_users_to_dynamic_roles.py")
    if unmigrated_perms > 0:
        print("  4. Run: python3 migrate_role_permissions_to_dynamic_roles.py")
    print("  5. Deploy latest backend code and restart server")

print("\n" + "=" * 80)

db.close()