package repository

import (
	"database/sql"
	"fmt"

	"vidarchive/internal/models"
)

type PresetRepository struct {
	db *sql.DB
}

func NewPresetRepository(db *sql.DB) *PresetRepository {
	return &PresetRepository{db: db}
}

func insertPreset(tx *sql.Tx, p *models.Preset) error {
	result, err := tx.Exec(
		`INSERT INTO presets (name, description, is_default, format_mode, format, quality, custom_format, extract_audio, audio_format, embed_subs, sub_langs, embed_thumbnail, embed_metadata, write_info_json, write_comments, comment_sort, max_comments, comment_extractor_args, custom_flags)
		 VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)`,
		p.Name, p.Description, boolToInt(p.IsDefault), p.FormatMode, p.Format, p.Quality, p.CustomFormat,
		boolToInt(p.ExtractAudio), p.AudioFormat, boolToInt(p.EmbedSubs), p.SubLangs,
		boolToInt(p.EmbedThumbnail), boolToInt(p.EmbedMetadata), boolToInt(p.WriteInfoJSON),
		boolToInt(p.WriteComments), p.CommentSort, p.MaxComments, p.CommentExtractorArgs,
		p.CustomFlags,
	)
	if err != nil {
		return err
	}
	id, err := result.LastInsertId()
	if err != nil {
		return fmt.Errorf("preset last insert id: %w", err)
	}
	p.ID = id
	return nil
}

func updatePreset(tx *sql.Tx, p *models.Preset) error {
	_, err := tx.Exec(
		`UPDATE presets SET name=?, description=?, is_default=?, format_mode=?, format=?, quality=?, custom_format=?, extract_audio=?, audio_format=?, embed_subs=?, sub_langs=?, embed_thumbnail=?, embed_metadata=?, write_info_json=?, write_comments=?, comment_sort=?, max_comments=?, comment_extractor_args=?, custom_flags=?
		 WHERE id=?`,
		p.Name, p.Description, boolToInt(p.IsDefault), p.FormatMode, p.Format, p.Quality, p.CustomFormat,
		boolToInt(p.ExtractAudio), p.AudioFormat, boolToInt(p.EmbedSubs), p.SubLangs,
		boolToInt(p.EmbedThumbnail), boolToInt(p.EmbedMetadata), boolToInt(p.WriteInfoJSON),
		boolToInt(p.WriteComments), p.CommentSort, p.MaxComments, p.CommentExtractorArgs,
		p.CustomFlags, p.ID,
	)
	return err
}

func clearDefault(tx *sql.Tx) error {
	_, err := tx.Exec(`UPDATE presets SET is_default = 0`)
	return err
}

// Save clears the previous default in the same transaction, so a mid-sequence
// failure cannot leave the library with no default set. Create and Update both
// route through here, so the exclusive-default invariant can't be bypassed.
func (r *PresetRepository) Save(p *models.Preset) error {
	tx, err := r.db.Begin()
	if err != nil {
		return err
	}
	defer tx.Rollback()

	if p.IsDefault {
		if err := clearDefault(tx); err != nil {
			return err
		}
	}
	if p.ID == 0 {
		err = insertPreset(tx, p)
	} else {
		err = updatePreset(tx, p)
	}
	if err != nil {
		return err
	}
	return tx.Commit()
}

func (r *PresetRepository) GetByID(id int64) (*models.Preset, error) {
	row := r.db.QueryRow(
		`SELECT id, name, description, is_default, format_mode, format, quality, custom_format, extract_audio, audio_format, embed_subs, sub_langs, embed_thumbnail, embed_metadata, write_info_json, write_comments, comment_sort, max_comments, comment_extractor_args, custom_flags, created_at
		 FROM presets WHERE id = ?`, id,
	)
	return scanPreset(row)
}

func (r *PresetRepository) GetAll() ([]*models.Preset, error) {
	rows, err := r.db.Query(
		`SELECT id, name, description, is_default, format_mode, format, quality, custom_format, extract_audio, audio_format, embed_subs, sub_langs, embed_thumbnail, embed_metadata, write_info_json, write_comments, comment_sort, max_comments, comment_extractor_args, custom_flags, created_at
		 FROM presets ORDER BY name`,
	)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	var presets []*models.Preset
	for rows.Next() {
		p, err := scanPreset(rows)
		if err != nil {
			return nil, err
		}
		presets = append(presets, p)
	}
	return presets, rows.Err()
}

func (r *PresetRepository) GetDefault() (*models.Preset, error) {
	row := r.db.QueryRow(
		`SELECT id, name, description, is_default, format_mode, format, quality, custom_format, extract_audio, audio_format, embed_subs, sub_langs, embed_thumbnail, embed_metadata, write_info_json, write_comments, comment_sort, max_comments, comment_extractor_args, custom_flags, created_at
		 FROM presets WHERE is_default = 1 LIMIT 1`,
	)
	return scanPreset(row)
}

func (r *PresetRepository) Delete(id int64) error {
	_, err := r.db.Exec(`DELETE FROM presets WHERE id = ?`, id)
	return err
}

func scanPreset(row interface{ Scan(...interface{}) error }) (*models.Preset, error) {
	var p models.Preset
	var isDefault, extractAudio, embedSubs, embedThumbnail, embedMetadata, writeInfoJSON, writeComments, maxComments int
	var description, formatMode, format, quality, customFormat, audioFormat, subLangs, commentSort, commentExtractorArgs, customFlags sql.NullString
	err := row.Scan(
		&p.ID, &p.Name, &description, &isDefault, &formatMode, &format, &quality, &customFormat,
		&extractAudio, &audioFormat, &embedSubs, &subLangs,
		&embedThumbnail, &embedMetadata, &writeInfoJSON,
		&writeComments, &commentSort, &maxComments, &commentExtractorArgs,
		&customFlags, &p.CreatedAt,
	)
	if err != nil {
		return nil, err
	}
	p.Description = description.String
	p.FormatMode = formatMode.String
	p.Format = format.String
	p.Quality = quality.String
	p.CustomFormat = customFormat.String
	p.AudioFormat = audioFormat.String
	p.SubLangs = subLangs.String
	p.CustomFlags = customFlags.String
	p.CommentSort = commentSort.String
	p.CommentExtractorArgs = commentExtractorArgs.String
	p.MaxComments = maxComments
	p.IsDefault = isDefault == 1
	p.ExtractAudio = extractAudio == 1
	p.EmbedSubs = embedSubs == 1
	p.EmbedThumbnail = embedThumbnail == 1
	p.EmbedMetadata = embedMetadata == 1
	p.WriteInfoJSON = writeInfoJSON == 1
	p.WriteComments = writeComments == 1
	return &p, nil
}

func boolToInt(b bool) int {
	if b {
		return 1
	}
	return 0
}