package core

func AddSourceToChannel(db DB, channel string, source string) error {
	_, err := db.Exec(`
		insert into channels (name, source)
		values (?, ?)
	`, channel, source)
	return err
}

func DeleteSourceFromChannel(db DB, channel string, source string) error {
	_, err := db.Exec(`
		delete from channels
		where name = ? and source = ?
	`, channel, source)
	return err
}

func GetSourcesInChannel(db DB) (map[string][]string, error) {
	rows, err := db.Query(`
		select name, source
		from channels
		order by name, source
	`)
	if err != nil {
		return nil, err
	}
	defer rows.Close()
	channelSources := make(map[string][]string)
	for rows.Next() {
		var name, source string
		if err := rows.Scan(&name, &source); err != nil {
			return nil, err
		}
		channelSources[name] = append(channelSources[name], source)
	}
	if err := rows.Err(); err != nil {
		return nil, err
	}
	return channelSources, nil
}

func GetChannelsAndActiveCounts(db DB) (map[string]int, error) {
	rows, err := db.Query(`
		select c.name, count(i.id) as count
		from channels c
		left outer join items i on c.source = i.source and i.active = 1
		group by c.name
	`)
	if err != nil {
		return nil, err
	}
	defer rows.Close()
	channelCounts := make(map[string]int)
	for rows.Next() {
		var name string
		var count int
		if err := rows.Scan(&name, &count); err != nil {
			return nil, err
		}
		channelCounts[name] = count
	}
	if err := rows.Err(); err != nil {
		return nil, err
	}
	return channelCounts, nil
}