"""
Purge seed/demo data from the database.

This is used when transitioning an environment from dev/test to production-like.
Triggered by setting ORCHARD_PURGE_SEED_DATA=true environment variable.
"""
import logging
import os
from sqlalchemy.orm import Session

from .models import (
    Project,
    Package,
    Artifact,
    Upload,
    PackageVersion,
    ArtifactDependency,
    Team,
    TeamMembership,
    User,
    AccessPermission,
)
from .storage import get_storage

logger = logging.getLogger(__name__)

# Seed data identifiers (from seed.py)
SEED_PROJECT_NAMES = [
    "frontend-libs",
    "backend-services",
    "mobile-apps",
    "internal-tools",
]

SEED_TEAM_SLUG = "demo-team"

SEED_USERNAMES = [
    "alice",
    "bob",
    "charlie",
    "diana",
    "eve",
    "frank",
]


def should_purge_seed_data() -> bool:
    """Check if seed data should be purged based on environment variable."""
    return os.environ.get("ORCHARD_PURGE_SEED_DATA", "").lower() == "true"


def purge_seed_data(db: Session) -> dict:
    """
    Purge all seed/demo data from the database.

    Returns a dict with counts of deleted items.
    """
    logger.warning("PURGING SEED DATA - This will delete demo projects, users, and teams")

    results = {
        "dependencies_deleted": 0,
        "versions_deleted": 0,
        "uploads_deleted": 0,
        "artifacts_deleted": 0,
        "packages_deleted": 0,
        "projects_deleted": 0,
        "permissions_deleted": 0,
        "team_memberships_deleted": 0,
        "users_deleted": 0,
        "teams_deleted": 0,
        "s3_objects_deleted": 0,
    }

    storage = get_storage()

    # Find seed projects
    seed_projects = db.query(Project).filter(Project.name.in_(SEED_PROJECT_NAMES)).all()
    seed_project_ids = [p.id for p in seed_projects]

    if not seed_projects:
        logger.info("No seed projects found, nothing to purge")
        return results

    logger.info(f"Found {len(seed_projects)} seed projects to purge")

    # Find packages in seed projects
    seed_packages = db.query(Package).filter(Package.project_id.in_(seed_project_ids)).all()
    seed_package_ids = [p.id for p in seed_packages]

    # Find artifacts in seed packages (via uploads)
    seed_uploads = db.query(Upload).filter(Upload.package_id.in_(seed_package_ids)).all()
    seed_artifact_ids = list(set(u.artifact_id for u in seed_uploads))

    # Delete in order (respecting foreign keys)

    # 1. Delete artifact dependencies
    if seed_artifact_ids:
        count = db.query(ArtifactDependency).filter(
            ArtifactDependency.artifact_id.in_(seed_artifact_ids)
        ).delete(synchronize_session=False)
        results["dependencies_deleted"] = count
        logger.info(f"Deleted {count} artifact dependencies")

    # 2. Delete package versions
    if seed_package_ids:
        count = db.query(PackageVersion).filter(
            PackageVersion.package_id.in_(seed_package_ids)
        ).delete(synchronize_session=False)
        results["versions_deleted"] = count
        logger.info(f"Deleted {count} package versions")

    # 3. Delete uploads
    if seed_package_ids:
        count = db.query(Upload).filter(Upload.package_id.in_(seed_package_ids)).delete(
            synchronize_session=False
        )
        results["uploads_deleted"] = count
        logger.info(f"Deleted {count} uploads")

    # 4. Delete S3 objects for seed artifacts
    if seed_artifact_ids:
        seed_artifacts = db.query(Artifact).filter(Artifact.id.in_(seed_artifact_ids)).all()
        for artifact in seed_artifacts:
            if artifact.s3_key:
                try:
                    storage.client.delete_object(Bucket=storage.bucket, Key=artifact.s3_key)
                    results["s3_objects_deleted"] += 1
                except Exception as e:
                    logger.warning(f"Failed to delete S3 object {artifact.s3_key}: {e}")
        logger.info(f"Deleted {results['s3_objects_deleted']} S3 objects")

    # 5. Delete artifacts (only those with ref_count that would be 0 after our deletions)
    # Since we deleted all versions pointing to these artifacts, we can delete them
    if seed_artifact_ids:
        count = db.query(Artifact).filter(Artifact.id.in_(seed_artifact_ids)).delete(
            synchronize_session=False
        )
        results["artifacts_deleted"] = count
        logger.info(f"Deleted {count} artifacts")

    # 6. Delete packages
    if seed_package_ids:
        count = db.query(Package).filter(Package.id.in_(seed_package_ids)).delete(
            synchronize_session=False
        )
        results["packages_deleted"] = count
        logger.info(f"Deleted {count} packages")

    # 7. Delete access permissions for seed projects
    if seed_project_ids:
        count = db.query(AccessPermission).filter(
            AccessPermission.project_id.in_(seed_project_ids)
        ).delete(synchronize_session=False)
        results["permissions_deleted"] = count
        logger.info(f"Deleted {count} access permissions")

    # 8. Delete seed projects
    count = db.query(Project).filter(Project.name.in_(SEED_PROJECT_NAMES)).delete(
        synchronize_session=False
    )
    results["projects_deleted"] = count
    logger.info(f"Deleted {count} projects")

    # 9. Find and delete seed team
    seed_team = db.query(Team).filter(Team.slug == SEED_TEAM_SLUG).first()
    if seed_team:
        # Delete team memberships first
        count = db.query(TeamMembership).filter(
            TeamMembership.team_id == seed_team.id
        ).delete(synchronize_session=False)
        results["team_memberships_deleted"] = count
        logger.info(f"Deleted {count} team memberships")

        # Delete the team
        db.delete(seed_team)
        results["teams_deleted"] = 1
        logger.info(f"Deleted team: {SEED_TEAM_SLUG}")

    # 10. Delete seed users (but NOT admin)
    seed_users = db.query(User).filter(User.username.in_(SEED_USERNAMES)).all()
    for user in seed_users:
        # Delete any remaining team memberships for this user
        db.query(TeamMembership).filter(TeamMembership.user_id == user.id).delete(
            synchronize_session=False
        )
        # Delete any access permissions for this user
        # Note: AccessPermission.user_id is VARCHAR (username), not UUID
        db.query(AccessPermission).filter(AccessPermission.user_id == user.username).delete(
            synchronize_session=False
        )
        db.delete(user)
        results["users_deleted"] += 1

    if results["users_deleted"] > 0:
        logger.info(f"Deleted {results['users_deleted']} seed users")

    db.commit()

    logger.warning("SEED DATA PURGE COMPLETE")
    logger.info(f"Purge results: {results}")

    return results