from dataclasses import dataclass
from datetime import date, datetime

import psycopg

from lyra_worker.browser import MbBrowser
from lyra_worker.release_filter import is_core_release

_TRUE = {"1", "true", "yes", "on"}


@dataclass(frozen=True)
class MonitorConfig:
    enabled: bool = False
    poll_interval_hours: int = 24
    retry_interval_hours: int = 6
    quality_cutoff: int = 2
    upgrade_window_days: int = 14

    @classmethod
    def from_config(cls, config: dict) -> "MonitorConfig":
        def _int(key: str, default: int) -> int:
            try:
                return int(config[key])
            except (KeyError, TypeError, ValueError):
                return default

        return cls(
            enabled=str(config.get("monitor.enabled", "")).strip().lower() in _TRUE,
            poll_interval_hours=_int("monitor.pollIntervalHours", 24),
            retry_interval_hours=_int("monitor.retryIntervalHours", 6),
            quality_cutoff=_int("monitor.qualityCutoff", 2),
            upgrade_window_days=_int("monitor.upgradeWindowDays", 14),
        )


def _is_new(first_release_date: str, monitor_from: datetime) -> bool:
    """A release is 'new going forward' if its first-release date is after monitorFrom."""
    if not first_release_date:
        return False
    try:
        frd = date.fromisoformat(first_release_date[:10])
    except ValueError:
        return False
    return frd > monitor_from.date()


def discover(conn: psycopg.Connection, browser: MbBrowser, cfg: MonitorConfig) -> int:
    """Poll each due watched artist; insert newly-seen release-groups. Returns #rows inserted."""
    with conn.cursor() as cur:
        cur.execute(
            'SELECT id, mbid, name, "autoMonitorFuture", "monitorFrom" FROM "WatchedArtist" '
            'WHERE "lastPolledAt" IS NULL '
            '   OR "lastPolledAt" < now() - make_interval(hours => %s)',
            (cfg.poll_interval_hours,),
        )
        artists = cur.fetchall()

    inserted = 0
    for artist_id, mbid, name, auto_future, monitor_from in artists:
        for rg in browser.browse_release_groups(mbid):
            monitored = (
                bool(auto_future)
                and _is_new(rg.first_release_date, monitor_from)
                and is_core_release(rg.primary_type, rg.secondary_types)
            )
            with conn.cursor() as cur:
                cur.execute(
                    'INSERT INTO "MonitoredRelease" (id, "watchedArtistId", "artistMbid", '
                    '"artistName", "rgMbid", album, "primaryType", "secondaryTypes", '
                    '"firstReleaseDate", monitored, state, "createdAt") '
                    "VALUES (gen_random_uuid()::text, %s, %s, %s, %s, %s, %s, %s, %s, %s, 'wanted', now()) "
                    'ON CONFLICT ("rgMbid") DO NOTHING',
                    (artist_id, mbid, name, rg.rg_mbid, rg.title, rg.primary_type or None,
                     list(rg.secondary_types), rg.first_release_date or None, monitored),
                )
                inserted += cur.rowcount
        with conn.cursor() as cur:
            cur.execute('UPDATE "WatchedArtist" SET "lastPolledAt" = now() WHERE id = %s', (artist_id,))
    conn.commit()
    return inserted


def _set_state(conn: psycopg.Connection, rel_id: str, state: str) -> None:
    with conn.cursor() as cur:
        cur.execute('UPDATE "MonitoredRelease" SET state = %s WHERE id = %s', (state, rel_id))


def _in_library_at_cutoff(conn: psycopg.Connection, artist: str, album: str, cutoff: int) -> bool:
    with conn.cursor() as cur:
        cur.execute(
            'SELECT 1 FROM "LibraryItem" WHERE artist = %s AND album = %s '
            'AND "qualityClass" >= %s LIMIT 1',
            (artist, album, cutoff),
        )
        return cur.fetchone() is not None


def _enqueue_one(conn: psycopg.Connection, rel_id: str, artist: str, album: str) -> None:
    with conn.cursor() as cur:
        cur.execute(
            'INSERT INTO "Request" (id, artist, album, status, "monitoredReleaseId", "createdAt") '
            "VALUES (gen_random_uuid()::text, %s, %s, 'pending', %s, now()) RETURNING id",
            (artist, album, rel_id),
        )
        request_id = cur.fetchone()[0]
        cur.execute(
            'INSERT INTO "Job" (id, "requestId", state, "currentStage", attempts, "createdAt", "updatedAt") '
            "VALUES (gen_random_uuid()::text, %s, 'requested', 'intake', 0, now(), now())",
            (request_id,),
        )
        cur.execute('UPDATE "MonitoredRelease" SET "lastSearchedAt" = now() WHERE id = %s', (rel_id,))


def enqueue_due(conn: psycopg.Connection, cfg: MonitorConfig) -> int:
    """Enqueue due wanted/upgrade releases as pipeline jobs. Returns #jobs enqueued."""
    with conn.cursor() as cur:
        cur.execute(
            'SELECT mr.id, mr."artistName", mr.album, mr.state, mr."currentQualityClass", '
            '  (mr."firstGrabbedAt" IS NOT NULL '
            '   AND mr."firstGrabbedAt" < now() - make_interval(days => %s)) AS window_expired '
            'FROM "MonitoredRelease" mr '
            'WHERE mr.monitored = true '
            "  AND mr.state <> 'fulfilled' "
            '  AND (mr."lastSearchedAt" IS NULL '
            '       OR mr."lastSearchedAt" < now() - make_interval(hours => %s)) '
            '  AND NOT EXISTS ('
            '    SELECT 1 FROM "Request" r JOIN "Job" j ON j."requestId" = r.id '
            '    WHERE r."monitoredReleaseId" = mr.id '
            "      AND j.state NOT IN ('imported', 'needs_attention'))",
            (cfg.upgrade_window_days, cfg.retry_interval_hours),
        )
        rows = cur.fetchall()

    enqueued = 0
    for rel_id, artist, album, state, quality, window_expired in rows:
        if _in_library_at_cutoff(conn, artist, album, cfg.quality_cutoff):
            _set_state(conn, rel_id, "fulfilled")
            continue
        if state == "grabbed" and (window_expired or (quality is not None and quality >= cfg.quality_cutoff)):
            _set_state(conn, rel_id, "fulfilled")
            continue
        _enqueue_one(conn, rel_id, artist, album)
        enqueued += 1
    conn.commit()
    return enqueued


def fulfill_owned_releases(conn: psycopg.Connection, cfg: MonitorConfig) -> int:
    """Mark fulfilled any monitored, not-yet-fulfilled release already owned at/above the
    quality cutoff. Run once at startup so releases pressed while the monitor was off (and
    therefore never reconciled) drop off the wanted list. Idempotent. Returns #rows fixed."""
    with conn.cursor() as cur:
        cur.execute(
            'UPDATE "MonitoredRelease" mr SET state = \'fulfilled\', '
            '  "currentQualityClass" = li.q, '
            '  "firstGrabbedAt" = COALESCE(mr."firstGrabbedAt", now()) '
            'FROM (SELECT artist, album, max("qualityClass") AS q FROM "LibraryItem" '
            '      GROUP BY artist, album) li '
            'WHERE li.artist = mr."artistName" AND li.album = mr.album '
            "  AND mr.monitored = true AND mr.state <> 'fulfilled' AND li.q >= %s",
            (cfg.quality_cutoff,),
        )
        fixed = cur.rowcount
    conn.commit()
    return fixed


def reconcile(conn: psycopg.Connection, job_id: str, cfg: MonitorConfig) -> None:
    """Feed a finished job's outcome back into its MonitoredRelease (if any)."""
    with conn.cursor() as cur:
        cur.execute(
            'SELECT j.state, r."monitoredReleaseId", r.artist, r.album '
            'FROM "Job" j JOIN "Request" r ON r.id = j."requestId" WHERE j.id = %s',
            (job_id,),
        )
        row = cur.fetchone()
    if row is None:
        return
    state, rel_id, artist, album = row
    if rel_id is None or state != "imported":
        return  # needs_attention (or in-flight) leaves the release wanted

    with conn.cursor() as cur:
        cur.execute(
            'SELECT "qualityClass" FROM "LibraryItem" WHERE artist = %s AND album = %s',
            (artist, album),
        )
        lib = cur.fetchone()
    quality = lib[0] if lib else None
    new_state = "fulfilled" if (quality is not None and quality >= cfg.quality_cutoff) else "grabbed"
    with conn.cursor() as cur:
        cur.execute(
            'UPDATE "MonitoredRelease" '
            'SET "currentQualityClass" = %s, state = %s, '
            '    "firstGrabbedAt" = COALESCE("firstGrabbedAt", now()) WHERE id = %s',
            (quality, new_state, rel_id),
        )
    conn.commit()


def sweep(conn: psycopg.Connection, browser: MbBrowser, cfg: MonitorConfig) -> None:
    """One monitor pass: discover new releases, then enqueue everything due."""
    discover(conn, browser, cfg)
    enqueue_due(conn, cfg)