"""
Django management command to delete a user while preserving their submissions.

Usage:
    uv run manage.py delete_user <username>
    uv run manage.py delete_user --user-id <user_id>
    uv run manage.py delete_user <username> --dry-run
"""

from django.core.management.base import BaseCommand, CommandError
from apps.accounts.models import User
from apps.accounts.services import UserDeletionService


class Command(BaseCommand):
    help = "Delete a user while preserving all their submissions"

    def add_arguments(self, parser):
        parser.add_argument(
            "username", nargs="?", type=str, help="Username of the user to delete"
        )
        parser.add_argument(
            "--user-id",
            type=str,
            help="User ID of the user to delete (alternative to username)",
        )
        parser.add_argument(
            "--dry-run",
            action="store_true",
            help="Show what would be deleted without actually deleting",
        )
        parser.add_argument(
            "--force", action="store_true", help="Skip confirmation prompt"
        )

    def handle(self, *args, **options):
        username = options.get("username")
        user_id = options.get("user_id")
        dry_run = options.get("dry_run", False)
        force = options.get("force", False)

        # Validate arguments
        if not username and not user_id:
            raise CommandError("You must provide either a username or --user-id")

        if username and user_id:
            raise CommandError("You cannot provide both username and --user-id")

        # Find the user
        try:
            if username:
                user = User.objects.get(username=username)
            else:
                user = User.objects.get(user_id=user_id)
        except User.DoesNotExist:
            identifier = username or user_id
            raise CommandError(f'User "{identifier}" does not exist')

        # Check if user can be deleted
        can_delete, reason = UserDeletionService.can_delete_user(user)
        if not can_delete:
            raise CommandError(f"Cannot delete user: {reason}")

        # Count submissions
        submission_counts = {
            "park_reviews": getattr(
                user, "park_reviews", user.__class__.objects.none()
            ).count(),
            "ride_reviews": getattr(
                user, "ride_reviews", user.__class__.objects.none()
            ).count(),
            "uploaded_park_photos": getattr(
                user, "uploaded_park_photos", user.__class__.objects.none()
            ).count(),
            "uploaded_ride_photos": getattr(
                user, "uploaded_ride_photos", user.__class__.objects.none()
            ).count(),
            "top_lists": getattr(
                user, "top_lists", user.__class__.objects.none()
            ).count(),
            "edit_submissions": getattr(
                user, "edit_submissions", user.__class__.objects.none()
            ).count(),
            "photo_submissions": getattr(
                user, "photo_submissions", user.__class__.objects.none()
            ).count(),
        }

        total_submissions = sum(submission_counts.values())

        # Display user information
        self.stdout.write(self.style.WARNING("\nUser Information:"))
        self.stdout.write(f"  Username: {user.username}")
        self.stdout.write(f"  User ID: {user.user_id}")
        self.stdout.write(f"  Email: {user.email}")
        self.stdout.write(f"  Date Joined: {user.date_joined}")
        self.stdout.write(f"  Role: {user.role}")

        # Display submission counts
        self.stdout.write(self.style.WARNING("\nSubmissions to preserve:"))
        for submission_type, count in submission_counts.items():
            if count > 0:
                self.stdout.write(
                    f'  {submission_type.replace("_", " ").title()}: {count}'
                )

        self.stdout.write(f"\nTotal submissions: {total_submissions}")

        if total_submissions > 0:
            self.stdout.write(
                self.style.SUCCESS(
                    f'\nAll {total_submissions} submissions will be transferred to the "deleted_user" placeholder.'
                )
            )
        else:
            self.stdout.write(
                self.style.WARNING("\nNo submissions found for this user.")
            )

        if dry_run:
            self.stdout.write(self.style.SUCCESS("\n[DRY RUN] No changes were made."))
            return

        # Confirmation prompt
        if not force:
            self.stdout.write(
                self.style.WARNING(
                    f'\nThis will permanently delete the user "{user.username}" '
                    f"but preserve all {total_submissions} submissions."
                )
            )
            confirm = input("Are you sure you want to continue? (yes/no): ")
            if confirm.lower() not in ["yes", "y"]:
                self.stdout.write(self.style.ERROR("Operation cancelled."))
                return

        # Perform the deletion
        try:
            result = UserDeletionService.delete_user_preserve_submissions(user)

            self.stdout.write(
                self.style.SUCCESS(
                    f'\nSuccessfully deleted user "{result["deleted_user"]["username"]}"'
                )
            )

            preserved_count = sum(result["preserved_submissions"].values())
            if preserved_count > 0:
                self.stdout.write(
                    self.style.SUCCESS(
                        f'Preserved {preserved_count} submissions under user "{result["transferred_to"]["username"]}"'
                    )
                )

            # Show detailed preservation summary
            self.stdout.write(self.style.WARNING("\nPreservation Summary:"))
            for submission_type, count in result["preserved_submissions"].items():
                if count > 0:
                    self.stdout.write(
                        f'  {submission_type.replace("_", " ").title()}: {count}'
                    )

        except Exception as e:
            raise CommandError(f"Error deleting user: {str(e)}")