// Code generated by sqlc. DO NOT EDIT.
// versions:
//   sqlc v1.31.1
// source: missing_pairs.sql

package dbq

import (
	"context"

	"github.com/jackc/pgx/v5/pgtype"
)

const listMissingTrackPairs = `-- name: ListMissingTrackPairs :many

WITH grp AS (
  SELECT id AS album_id, COALESCE(release_group_mbid, id::text) AS g
    FROM albums
),
cand AS (
  SELECT m.id AS missing_id, p.id AS present_id, 'mbid'::text AS rule
    FROM tracks m
    JOIN grp gm ON gm.album_id = m.album_id
    JOIN grp gp ON gp.g = gm.g
    JOIN tracks p ON p.album_id = gp.album_id
                 AND p.missing_since IS NULL
                 AND p.mbid = m.mbid
   WHERE m.missing_since IS NOT NULL
     AND m.mbid IS NOT NULL
  UNION ALL
  SELECT m.id, p.id, 'title'::text
    FROM tracks m
    JOIN tracks p ON p.album_id = m.album_id
                 AND p.missing_since IS NULL
                 AND lower(p.title) = lower(m.title)
   WHERE m.missing_since IS NOT NULL
     AND (m.mbid IS NULL OR p.mbid IS NULL OR m.mbid = p.mbid)
),
pairs AS (
  -- A pair both rules found is one candidate, credited to the stronger rule.
  SELECT missing_id, present_id, min(rule)::text AS rule
    FROM cand
   GROUP BY missing_id, present_id
)
SELECT pr.missing_id, pr.present_id, pr.rule,
       m.file_path AS missing_path, p.file_path AS present_path,
       (count(*) OVER (PARTITION BY pr.missing_id))::int AS missing_candidates,
       (count(*) OVER (PARTITION BY pr.present_id))::int AS present_candidates
  FROM pairs pr
  JOIN tracks m ON m.id = pr.missing_id
  JOIN tracks p ON p.id = pr.present_id
 ORDER BY m.file_path, p.file_path
`

type ListMissingTrackPairsRow struct {
	MissingID         pgtype.UUID
	PresentID         pgtype.UUID
	Rule              string
	MissingPath       string
	PresentPath       string
	MissingCandidates int32
	PresentCandidates int32
}

// Missing-pair pass (M485). A track marked missing whose replacement is already
// on disk under another row — most often a Lidarr quality upgrade, mp3 → flac at
// a new path — is folded into that replacement, so its history moves across and
// re-acquisition stops chasing music the library already has.
//
// Move adoption (#2528) cannot catch these: it links a new file to a missing row
// at the moment the file is first inserted, and the replacement arrives as a
// re-encode with no recording MBID, so it has nothing to match on. AcoustID may
// give it an MBID later; by then both rows exist and only a fold can join them.
// Every candidate (missing, present) pair, with how many candidates each side
// has. Two rules, measured on the operator's library on 2026-10-07 (#5274):
//
//	mbid   the same recording MBID, within the album group (the album row, or
//	       albums sharing a release group). 142 of 359 pairs.
//	title  the same album row and the same title, ignoring case. 213 more. The
//	       replacements are often not the original file — another edition,
//	       re-encoded, untagged — so the metadata is what is left to go on.
//
// Deliberately NOT gated on duration or track position. On the 142 pairs known
// to be one recording, 18% differed by over 2s (old mp3 durations are poor
// estimates), and the poorly tagged set is exactly where numbering is broken.
//
// A pair whose MBIDs are both set and differ is not a title match: the tags say
// they are different recordings. The caller folds a pair only when each side has
// exactly one candidate; anything else is ambiguous and left alone.
func (q *Queries) ListMissingTrackPairs(ctx context.Context) ([]ListMissingTrackPairsRow, error) {
	rows, err := q.db.Query(ctx, listMissingTrackPairs)
	if err != nil {
		return nil, err
	}
	defer rows.Close()
	var items []ListMissingTrackPairsRow
	for rows.Next() {
		var i ListMissingTrackPairsRow
		if err := rows.Scan(
			&i.MissingID,
			&i.PresentID,
			&i.Rule,
			&i.MissingPath,
			&i.PresentPath,
			&i.MissingCandidates,
			&i.PresentCandidates,
		); err != nil {
			return nil, err
		}
		items = append(items, i)
	}
	if err := rows.Err(); err != nil {
		return nil, err
	}
	return items, nil
}

const lockTracksForPairing = `-- name: LockTracksForPairing :many
SELECT id, missing_since
  FROM tracks
 WHERE id = ANY($1::uuid[])
 ORDER BY id
   FOR UPDATE
`

type LockTracksForPairingRow struct {
	ID           pgtype.UUID
	MissingSince pgtype.Timestamptz
}

// Locks both rows of a pair for the fold's transaction, in id order so two
// passes cannot deadlock, and returns what the fold re-checks: the missing row
// must still be missing and the present one still present. A scan may have
// restored or adopted the first, or marked the second, since the pairs were listed.
func (q *Queries) LockTracksForPairing(ctx context.Context, ids []pgtype.UUID) ([]LockTracksForPairingRow, error) {
	rows, err := q.db.Query(ctx, lockTracksForPairing, ids)
	if err != nil {
		return nil, err
	}
	defer rows.Close()
	var items []LockTracksForPairingRow
	for rows.Next() {
		var i LockTracksForPairingRow
		if err := rows.Scan(&i.ID, &i.MissingSince); err != nil {
			return nil, err
		}
		items = append(items, i)
	}
	if err := rows.Err(); err != nil {
		return nil, err
	}
	return items, nil
}