/** C 老彩虹只选完整方块；禁止属性优先，允许的复合属性取靠后的池。 */
export function oldRainbowPool(info: any, buttonColors: number[] = [],
    type: number = info && info.type, color: number = info && info.color): number {
    if (!info || info.block === 23 || color === 11
        || [1, 9, 10, 11, 16, 18, 19, 20, 22].indexOf(type) >= 0
        || info.colorChange != null || info.colorArray != null
        || info.floor != null || info.floorMove === true || info.flowerReceive
        || buttonColors.indexOf(color) >= 0) return 0;
    if ([3, 4, 12].indexOf(type) >= 0) return 3;
    if ([2, 5, 6, 7, 8, 13, 14, 17, 21].indexOf(type) >= 0
        || info.flowerSend || info.lock != null || info.horizontal || info.vertical) return 2;
    return type === 0 ? 1 : 0;
}

export function chooseOldRainbowTarget<T extends { pool: number }>(
    candidates: T[], random: () => number = Math.random): T | null {
    const available = candidates.filter(candidate => candidate.pool > 0);
    if (!available.length) return null;
    const priority = Math.min(...available.map(candidate => candidate.pool));
    const pool = available.filter(candidate => candidate.pool === priority);
    return pool[Math.floor(random() * pool.length)];
}