package sniper

import (
	"errors"
	"fmt"
	"strconv"
	"strings"

	"huya-go/internal/huya"
)

// notFoundMessage 在未命中时把类目限制写进提示，便于区分「被类目过滤掉」与「列表里确实没有」。
func notFoundMessage(category string) string {
	if strings.TrimSpace(category) == "" {
		return "未查询到所需物品，继续监控"
	}
	return fmt.Sprintf("类目[%s]内未查询到所需物品，继续监控", strings.TrimSpace(category))
}

func matchPrize(prizes []huya.PrizeInfo, target Target) *huya.PrizeInfo {
	if target.Auto {
		return autoPrize(prizes, target)
	}
	for i := range prizes {
		if target.PID > 0 && int32(prizes[i].ID) != target.PID {
			continue
		}
		if target.PID == 0 && target.Name != "" && !strings.Contains(prizes[i].Name, target.Name) {
			continue
		}
		if target.MaxPrice > 0 && prizes[i].Price() > target.MaxPrice {
			continue
		}
		if target.MinLeft > 0 && prizes[i].EstimatedLeft() < target.MinLeft {
			continue
		}
		return &prizes[i]
	}
	return nil
}

func autoPrize(prizes []huya.PrizeInfo, target Target) *huya.PrizeInfo {
	var fallback *huya.PrizeInfo
	for i := range prizes {
		if target.MaxPrice > 0 && prizes[i].Price() > target.MaxPrice {
			continue
		}
		if target.MinLeft > 0 && prizes[i].EstimatedLeft() < target.MinLeft {
			continue
		}
		if fallback == nil {
			fallback = &prizes[i]
		}
		if prizes[i].EstimatedLeft() > 0 {
			return &prizes[i]
		}
	}
	return fallback
}

// exchangeSignals 汇总一次兑换响应里可用于判定的信号。
//
// 虎牙把失败原因分散在 msg / actPreCondition(Tip/ButtonDesc/ConditionParams)
// 和 exchangeInfo.desc 里，status 除 200 外没有可依据的公开语义，
// 所以判定顺序是：文案 -> 成功结构（status=200 且有 orderId）-> 结构门禁 -> 兜底失败。
type exchangeSignals struct {
	text          string
	status        int32
	hasOrderID    bool
	conditionType int32
}

func buildExchangeSignals(resp *huya.ScoreExchangePrizeResp) exchangeSignals {
	if resp == nil {
		return exchangeSignals{}
	}
	parts := []string{
		resp.Msg,
		resp.ActPreCondition.Tip,
		resp.ActPreCondition.ButtonDesc,
		resp.ExchangeInfo.Desc,
	}
	for _, value := range resp.ActPreCondition.ConditionParams {
		parts = append(parts, value)
	}
	texts := make([]string, 0, len(parts))
	for _, part := range parts {
		if item := strings.TrimSpace(part); item != "" {
			texts = append(texts, item)
		}
	}
	return exchangeSignals{
		text:          strings.Join(texts, " "),
		status:        resp.Status,
		hasOrderID:    strings.TrimSpace(resp.OrderID) != "",
		conditionType: resp.ActPreCondition.ConditionType,
	}
}

// classifyExchangeText 只依据文案判定失败原因，命中时返回分类。
//
// 判定顺序固定：未开放 → 售罄 → 货币/次数 → 会话失效 → 下架 → 限流。
// 顺序很关键：限流关键词里有「稍后重试」「稍后」，如果排在前面会把更具体的原因吃掉。
// 2026-10-16 的日志里 244 条「领取频率限制，请稍后重试！！」和 917 条「活动太火爆了，
// 请稍后重试」过去全落到 failed：既看不出是被限流，也享受不到限流该有的退避语义。
func classifyExchangeText(text string) (string, bool) {
	switch {
	case containsAny(text, "暂未开放", "未开放", "未开始", "活动未开始"):
		return CategoryNotOpen, true
	case containsAny(text, "已抢完", "已抢光", "已兑完", "已售完", "库存不足", "没有库存", "领完了", "库存已耗完"):
		return CategorySoldOut, true
	case containsAny(text, "货币不足", "积分不足", "余额不足", "点券不足", "不足"):
		return CategoryNotEnough, true
	case containsAny(text, "已兑换", "重复兑换", "已领取", "超过兑换次数", "达到上限", "限购"):
		return CategoryAlreadyDone, true
	case containsAny(text, "账号未绑定", "未绑定账号", "未绑定手机", "登录态", "登录失效", "请先登录", "凭证失效", "token 失效"):
		return CategorySessionLost, true
	case containsAny(text, "奖品已下架", "已下架", "奖品不存在", "活动不存在"):
		return CategoryOffShelf, true
	case containsAny(text, "操作频繁", "太频繁", "稍后再试", "稍后重试", "火爆", "频繁", "频率", "限流", "繁忙", "人多", "排队", "手慢", "点击太快", "请求过多", "行为异常"):
		return CategoryTooFrequent, true
	}
	return "", false
}

func ClassifyExchange(resp *huya.ScoreExchangePrizeResp, err error) string {
	if err != nil {
		// 协议层错误（缺少 tRsp/tResp、解码失败）单独归类：它不是业务失败，
		// 通常是服务端在高并发下回了错误信封，需要单独统计与排查。
		if errors.Is(err, huya.ErrProtocolResponse) {
			return CategoryProtocol
		}
		return CategoryError
	}
	if resp == nil {
		return CategoryFailed
	}
	if resp.Success() {
		return CategorySuccess
	}
	signals := buildExchangeSignals(resp)
	if category, ok := classifyExchangeText(signals.text); ok {
		return category
	}
	// 成功回包也可能不带中文文案：status=200 且有 orderId 视为成功。
	if signals.status == 200 && signals.hasOrderID {
		return CategorySuccess
	}
	// 没有文案但服务端回了 precondition 门禁，归为条件未达成，按可重试失败处理。
	if signals.conditionType != 0 {
		return CategoryCondition
	}
	return CategoryFailed
}

// ExchangeMessage 返回响应里最有代表性的提示文案，供日志与 GUI 展示。
func ExchangeMessage(resp *huya.ScoreExchangePrizeResp) string {
	if resp == nil {
		return ""
	}
	for _, text := range []string{
		resp.Msg,
		resp.ActPreCondition.Tip,
		resp.ActPreCondition.ButtonDesc,
		resp.ExchangeInfo.Desc,
	} {
		if strings.TrimSpace(text) != "" {
			return strings.TrimSpace(text)
		}
	}
	return ""
}

func containsAny(text string, needles ...string) bool {
	for _, needle := range needles {
		if strings.Contains(text, needle) {
			return true
		}
	}
	return false
}

func targetKey(target Target) string {
	return strings.Join([]string{
		strings.TrimSpace(target.Name),
		int32String(target.PID),
		strconv.FormatBool(target.Auto),
		int64String(target.MaxPrice),
		int64String(target.MinLeft),
	}, "\x00")
}