from datetime import date, datetime
from typing import Optional

from sqlalchemy import select
from sqlalchemy.dialects.sqlite import insert as sqlite_insert
from sqlalchemy.orm import Session

from gimme_job.constants import CONSECUTIVE_FAILURES_THRESHOLD
from gimme_job.models.db import (
    JobPosting,
    NotificationLog,
    SiteConfig,
    SiteManifestVersion,
    SiteRun,
    Summary,
)
from gimme_job.models.dto import JobPostingCandidate
from gimme_job.models.runtime import SiteRunResult


class JobPostingRepo:
    def upsert_candidates(
        self,
        session: Session,
        candidates: list[JobPostingCandidate],
        run_date: date,
    ) -> tuple[int, int]:
        """Upsert a list of candidates. Returns (total_processed, new_count)."""
        if not candidates:
            return 0, 0

        now = datetime.utcnow()
        new_count = 0

        for c in candidates:
            if not c.fingerprint:
                continue

            existing = session.execute(
                select(JobPosting).where(JobPosting.fingerprint == c.fingerprint)
            ).scalar_one_or_none()

            if existing:
                existing.last_seen_at = now
                existing.is_active = True
                existing.is_new = False
            else:
                posting = JobPosting(
                    site_id=c.site_id,
                    external_job_id=c.external_job_id,
                    title=c.title,
                    company=c.company,
                    location=c.location,
                    posted_text=c.posted_text,
                    posted_at_normalized=c.posted_at_normalized,
                    job_url=c.job_url,
                    salary_text=c.salary_text,
                    employment_type=c.employment_type,
                    raw_text=c.raw_text,
                    fingerprint=c.fingerprint,
                    run_date=run_date,
                    first_seen_at=now,
                    last_seen_at=now,
                    is_new=True,
                    is_active=True,
                )
                session.add(posting)
                new_count += 1

        session.flush()
        return len(candidates), new_count

    def get_today_new(self, session: Session, run_date: date) -> list[JobPosting]:
        return list(
            session.execute(
                select(JobPosting)
                .where(JobPosting.run_date == run_date, JobPosting.is_new == True)
                .order_by(JobPosting.site_id, JobPosting.first_seen_at)
            ).scalars().all()
        )

    def get_by_site(self, session: Session, site_id: str) -> list[JobPosting]:
        return list(
            session.execute(
                select(JobPosting)
                .where(JobPosting.site_id == site_id)
                .order_by(JobPosting.first_seen_at.desc())
            ).scalars().all()
        )


class SiteRunRepo:
    def record_run(self, session: Session, result: SiteRunResult) -> SiteRun:
        run = SiteRun(
            site_id=result.site_id,
            started_at=result.started_at,
            ended_at=result.ended_at or datetime.utcnow(),
            status=result.status.value,
            items_found=result.items_found,
            new_items=result.new_items,
            error_summary=result.error_summary,
            failure_classification=(
                result.failure_classification.value if result.failure_classification else None
            ),
            trace_path=str(result.trace_path) if result.trace_path else None,
            screenshot_path=str(result.screenshot_path) if result.screenshot_path else None,
            dom_snapshot_path=(
                str(result.dom_snapshot_path) if result.dom_snapshot_path else None
            ),
        )
        session.add(run)
        session.flush()
        return run

    def get_recent_runs(
        self, session: Session, site_id: str, limit: int = 10
    ) -> list[SiteRun]:
        return list(
            session.execute(
                select(SiteRun)
                .where(SiteRun.site_id == site_id)
                .order_by(SiteRun.started_at.desc())
                .limit(limit)
            ).scalars().all()
        )

    def get_consecutive_failures(self, session: Session, site_id: str) -> int:
        config = session.get(SiteConfig, site_id)
        return config.consecutive_failures if config else 0


class SiteConfigRepo:
    def _get_or_create(self, session: Session, site_id: str) -> SiteConfig:
        config = session.get(SiteConfig, site_id)
        if config is None:
            config = SiteConfig(site_id=site_id)
            session.add(config)
            session.flush()
        return config

    def get_all_enabled(self, session: Session) -> list[SiteConfig]:
        return list(
            session.execute(
                select(SiteConfig).where(SiteConfig.enabled == True)
            ).scalars().all()
        )

    def set_repair_needed(self, session: Session, site_id: str, value: bool) -> None:
        config = self._get_or_create(session, site_id)
        config.repair_needed = value
        session.flush()

    def increment_failure(self, session: Session, site_id: str) -> int:
        config = self._get_or_create(session, site_id)
        config.consecutive_failures += 1
        config.last_failure_at = datetime.utcnow()
        if config.consecutive_failures >= CONSECUTIVE_FAILURES_THRESHOLD:
            config.repair_needed = True
        session.flush()
        return config.consecutive_failures

    def reset_failures(self, session: Session, site_id: str) -> None:
        config = self._get_or_create(session, site_id)
        config.consecutive_failures = 0
        config.repair_needed = False
        config.last_success_at = datetime.utcnow()
        session.flush()

    def record_success(self, session: Session, site_id: str) -> None:
        config = self._get_or_create(session, site_id)
        config.consecutive_failures = 0
        config.last_success_at = datetime.utcnow()
        session.flush()


class NotificationLogRepo:
    def log_notification(
        self,
        session: Session,
        run_date: date,
        provider: str,
        status: str,
        error_message: Optional[str] = None,
    ) -> NotificationLog:
        log = NotificationLog(
            run_date=run_date,
            provider=provider,
            status=status,
            error_message=error_message,
            sent_at=datetime.utcnow(),
        )
        session.add(log)
        session.flush()
        return log


class SummaryRepo:
    def save_summary(
        self,
        session: Session,
        run_date: date,
        content: str,
        model_used: str,
    ) -> Summary:
        summary = Summary(
            run_date=run_date,
            content=content,
            model_used=model_used,
            created_at=datetime.utcnow(),
        )
        session.add(summary)
        session.flush()
        return summary

    def get_latest(self, session: Session, run_date: date) -> Optional[Summary]:
        return session.execute(
            select(Summary)
            .where(Summary.run_date == run_date)
            .order_by(Summary.created_at.desc())
            .limit(1)
        ).scalar_one_or_none()