package logic

import (
	"context"
	"math"
	"sync"
	"time"

	"big-qmt/go-client/config"
	"big-qmt/go-client/libs"
	"big-qmt/go-client/sdk"
)

type dipWatch struct {
	LastClose float64
	ExpiresAt time.Time
}

var openDip = struct {
	mu    sync.Mutex
	store map[string]dipWatch
}{store: map[string]dipWatch{}}

func openSignal(ctx context.Context, client *sdk.Client, books *OrderBook, ticks map[string]sdk.Tick, openSignals map[string]libs.SignalItem, marketOK bool, buyBudget *float64) {
	if !marketOK {
		return
	}
	if buyBudget == nil || *buyBudget <= 0 {
		return
	}
	state := getState()
	if state.LoadError != "" {
		logf("ERROR", "[ZT][开仓] 状态文件异常，禁止新开仓: %s", state.LoadError)
		return
	}
	for code := range openSignals {
		if code == "" {
			logf("ERROR", "[ZT][开仓] 无效股票代码")
			continue
		}
		if state.Get(code) != nil {
			continue
		}
		price := ticks[code].LastPrice
		if price <= 0 {
			continue
		}
		if !dipTriggered(&openDip.mu, openDip.store, "开仓", code, price) {
			continue
		}
		volume := calcBuyVolume(price, config.Account.BuyValue)
		if volume <= 0 {
			continue
		}
		estimated := price * float64(volume)
		if estimated > *buyBudget {
			logf("INFO", "[ZT][开仓] %s 可用买入预算不足，需要=%.2f 剩余=%.2f", code, estimated, *buyBudget)
			continue
		}
		orderID := newOrderTag("base")
		if !books.place(ctx, client, sideBuy, code, volume, orderID) {
			continue
		}
		setPending(state.Ensure(code), pendingBaseOpening, orderID)
		*buyBudget -= estimated
		state.Save()
		logf("INFO", "[ZT][开仓] %s 买入 %d 股", code, volume)
	}
}

func calcBuyVolume(price, buyValue float64) int {
	if price <= 0 || buyValue <= 0 {
		return 0
	}
	// 不足一手时仍按最低一手委托。
	hands := int(math.Floor(buyValue / (price * 100)))
	if hands == 0 {
		hands = 1
	}
	return hands * 100
}

func dipTriggered(mu *sync.Mutex, store map[string]dipWatch, tag, code string, price float64) bool {
	if price <= 0 {
		return false
	}
	mu.Lock()
	defer mu.Unlock()
	now := time.Now()
	watch, ok := store[code]
	if !ok || now.After(watch.ExpiresAt) || now.Equal(watch.ExpiresAt) {
		store[code] = dipWatch{LastClose: price, ExpiresAt: now.Add(time.Duration(config.Account.WatchTimeoutSec) * time.Second)}
		logf("INFO", "[%s-观察] %s 现价=%.2f", tag, code, price)
		return false
	}
	if price < watch.LastClose {
		watch.LastClose = price
		watch.ExpiresAt = now.Add(time.Duration(config.Account.WatchTimeoutSec) * time.Second)
		store[code] = watch
		logf("INFO", "[%s-下跌] %s 刷新低点=%.2f", tag, code, price)
		return false
	}
	rebound := (price - watch.LastClose) / watch.LastClose * 100
	if rebound <= 0 {
		return false
	}
	if rebound < config.Account.ReboundThreshold {
		logf("INFO", "[%s-等待] %s 反弹=%.2f%% 阈值=%.2f%%", tag, code, rebound, config.Account.ReboundThreshold)
		return false
	}
	delete(store, code)
	logf("INFO", "[%s-触发] %s 反弹=%.2f%% 低点=%.2f", tag, code, rebound, watch.LastClose)
	return true
}