import { TableNames } from '../../../game/ConfigTableData';
import { aiLog } from '../runtime/AiLog';
import { BattleBuffSlotType } from '../../../manager/battleBuff/BattleBuffTypes';

/** 局内 AI 可抽 functiontype 下限（新表 1~16；排除 type=3 局外即时） */
const AI_BUFF_FT_MIN = 1;
/** 局内 AI 可抽 functiontype 上限 */
const AI_BUFF_FT_MAX = 16;

/** Battlebuff 加权不重复抽取 */
export class AiBattlebuffPicker {
    /**
     * 按 type 与 weight 加权抽取不重复 buff id。
     * 仅 `type=1|2` 且 `functiontype∈[1,16]`；**排除 type=3**。
     * 新表无主动行时 `buffType=1` 返回 []。
     * @param buffType 1=主动，2=被动
     * @param count 目标个数
     * @param seed 随机种子
     */
    pick(buffType: 1 | 2, count: number, seed: number): number[] {
        const need = Math.max(0, Math.floor(Number(count) || 0));
        if (need <= 0) return [];

        const list = gg.data.table.getTableList<ITableBattlebuff>(TableNames.Battlebuff) ?? [];
        const ids: number[] = [];
        const weights: number[] = [];
        for (let i = 0; i < list.length; i++) {
            const row = list[i];
            const slotType = Math.floor(Number(row.type) || 0);
            if (slotType === BattleBuffSlotType.Auto) continue;
            if (slotType !== buffType) continue;
            const ft = Math.floor(Number(row.functiontype) || 0);
            if (ft < AI_BUFF_FT_MIN || ft > AI_BUFF_FT_MAX) continue;
            const w = Math.max(0, Math.floor(Number(row.weight) || 0));
            if (w <= 0) continue;
            const id = Math.floor(Number(row.id) || 0);
            if (id <= 0) continue;
            ids.push(id);
            weights.push(w);
        }
        if (ids.length < need) {
            aiLog(`[AiBattlebuffPicker] candidate shortage buffType=${buffType} need=${need} have=${ids.length}`);
            return [];
        }

        const picked: number[] = [];
        let rng = (Math.floor(Number(seed) || 0) >>> 0) || 1;
        for (let n = 0; n < need; n++) {
            let total = 0;
            for (let i = 0; i < weights.length; i++) total += weights[i];
            if (total <= 0) {
                aiLog(`[AiBattlebuffPicker] remaining weight 0 buffType=${buffType} picked=${picked.join(',')}`);
                return [];
            }
            rng = (rng * 1664525 + 1013904223) >>> 0;
            let roll = (rng / 4294967296) * total;
            let choose = -1;
            for (let i = 0; i < weights.length; i++) {
                roll -= weights[i];
                if (roll < 0) {
                    choose = i;
                    break;
                }
            }
            if (choose < 0) choose = weights.length - 1;
            picked.push(ids[choose]);
            ids.splice(choose, 1);
            weights.splice(choose, 1);
        }
        return picked;
    }
}