# app/modules/monitoring/services/background_tasks_service.py
"""
Background Tasks Service
Service for monitoring background tasks across the system
"""

from datetime import UTC, datetime

from sqlalchemy import case, desc, func
from sqlalchemy.orm import Session

from app.modules.dev_tools.models import ArchitectureScan, TestRun
from app.modules.marketplace.models import MarketplaceImportJob


class BackgroundTasksService:
    """Service for monitoring background tasks"""

    def get_import_jobs(
        self, db: Session, status: str | None = None, limit: int = 50
    ) -> list[MarketplaceImportJob]:
        """Get import jobs with optional status filter"""
        query = db.query(MarketplaceImportJob)
        if status:
            query = query.filter(MarketplaceImportJob.status == status)
        return query.order_by(desc(MarketplaceImportJob.created_at)).limit(limit).all()

    def get_test_runs(
        self, db: Session, status: str | None = None, limit: int = 50
    ) -> list[TestRun]:
        """Get test runs with optional status filter"""
        query = db.query(TestRun)
        if status:
            query = query.filter(TestRun.status == status)
        return query.order_by(desc(TestRun.timestamp)).limit(limit).all()

    def get_running_imports(self, db: Session) -> list[MarketplaceImportJob]:
        """Get currently running import jobs"""
        return (
            db.query(MarketplaceImportJob)
            .filter(MarketplaceImportJob.status == "processing")
            .all()
        )

    def get_running_test_runs(self, db: Session) -> list[TestRun]:
        """Get currently running test runs"""
        # noqa: SVC-005 - Platform-level, TestRuns not store-scoped
        return db.query(TestRun).filter(TestRun.status == "running").all()

    def get_import_stats(self, db: Session) -> dict:
        """Get import job statistics"""
        today_start = datetime.now(UTC).replace(
            hour=0, minute=0, second=0, microsecond=0
        )

        stats = db.query(
            func.count(MarketplaceImportJob.id).label("total"),
            func.sum(
                case((MarketplaceImportJob.status == "processing", 1), else_=0)
            ).label("running"),
            func.sum(
                case(
                    (
                        MarketplaceImportJob.status.in_(
                            ["completed", "completed_with_errors"]
                        ),
                        1,
                    ),
                    else_=0,
                )
            ).label("completed"),
            func.sum(
                case((MarketplaceImportJob.status == "failed", 1), else_=0)
            ).label("failed"),
        ).first()

        today_count = (
            db.query(func.count(MarketplaceImportJob.id))
            .filter(MarketplaceImportJob.created_at >= today_start)
            .scalar()
            or 0
        )

        return {
            "total": stats.total or 0,
            "running": stats.running or 0,
            "completed": stats.completed or 0,
            "failed": stats.failed or 0,
            "today": today_count,
        }

    def get_test_run_stats(self, db: Session) -> dict:
        """Get test run statistics"""
        today_start = datetime.now(UTC).replace(
            hour=0, minute=0, second=0, microsecond=0
        )

        stats = db.query(
            func.count(TestRun.id).label("total"),
            func.sum(case((TestRun.status == "running", 1), else_=0)).label(
                "running"
            ),
            func.sum(case((TestRun.status == "passed", 1), else_=0)).label(
                "completed"
            ),
            func.sum(
                case((TestRun.status.in_(["failed", "error"]), 1), else_=0)
            ).label("failed"),
            func.avg(TestRun.duration_seconds).label("avg_duration"),
        ).first()

        today_count = (
            db.query(func.count(TestRun.id))
            .filter(TestRun.timestamp >= today_start)
            .scalar()
            or 0
        )

        return {
            "total": stats.total or 0,
            "running": stats.running or 0,
            "completed": stats.completed or 0,
            "failed": stats.failed or 0,
            "today": today_count,
            "avg_duration": round(stats.avg_duration or 0, 1),
        }

    def get_code_quality_scans(
        self, db: Session, status: str | None = None, limit: int = 50
    ) -> list[ArchitectureScan]:
        """Get code quality scans with optional status filter"""
        query = db.query(ArchitectureScan)
        if status:
            query = query.filter(ArchitectureScan.status == status)
        return query.order_by(desc(ArchitectureScan.timestamp)).limit(limit).all()

    def get_running_scans(self, db: Session) -> list[ArchitectureScan]:
        """Get currently running code quality scans"""
        return (
            db.query(ArchitectureScan)
            .filter(ArchitectureScan.status.in_(["pending", "running"]))
            .all()
        )

    def get_scan_stats(self, db: Session) -> dict:
        """Get code quality scan statistics"""
        today_start = datetime.now(UTC).replace(
            hour=0, minute=0, second=0, microsecond=0
        )

        stats = db.query(
            func.count(ArchitectureScan.id).label("total"),
            func.sum(
                case(
                    (ArchitectureScan.status.in_(["pending", "running"]), 1), else_=0
                )
            ).label("running"),
            func.sum(
                case(
                    (
                        ArchitectureScan.status.in_(
                            ["completed", "completed_with_warnings"]
                        ),
                        1,
                    ),
                    else_=0,
                )
            ).label("completed"),
            func.sum(
                case((ArchitectureScan.status == "failed", 1), else_=0)
            ).label("failed"),
            func.avg(ArchitectureScan.duration_seconds).label("avg_duration"),
        ).first()

        today_count = (
            db.query(func.count(ArchitectureScan.id))
            .filter(ArchitectureScan.timestamp >= today_start)
            .scalar()
            or 0
        )

        return {
            "total": stats.total or 0,
            "running": stats.running or 0,
            "completed": stats.completed or 0,
            "failed": stats.failed or 0,
            "today": today_count,
            "avg_duration": round(stats.avg_duration or 0, 1),
        }


# Singleton instance
background_tasks_service = BackgroundTasksService()