package aiser

import (
	"context"
	"errors"
	"fmt"
	"math"
	"time"

	"91porn-server/app/appg"
	"91porn-server/common/constant/redisconst"
	"91porn-server/common/db"
	"91porn-server/common/laosiji_app"
	"91porn-server/common/log"
	"91porn-server/common/redis"
	"91porn-server/models/commod"
	"91porn-server/models/v/fundtransferlogmod"
	"91porn-server/models/v/usermod"
	"91porn-server/models/v/walletmod"

	"github.com/go-redsync/redsync/v4"
	"github.com/shopspring/decimal"
	"go.mongodb.org/mongo-driver/bson/primitive"
)

const aiFundLockExpiry = 30 * time.Second

type GetAuthURLResp struct {
	URL string `json:"url"`
}

type transferDependencies struct {
	findLatest    func(uint64, fundtransferlogmod.Category) (*fundtransferlogmod.FundTransferLog, error)
	findLatestOut func(uint64, fundtransferlogmod.Category) (*fundtransferlogmod.FundTransferLog, error)
	getWallet     func(uint64) (*walletmod.Wallet, error)
	findUser      func(uint64) (*usermod.User, error)
	getAuthURL    func(context.Context, laosiji_app.GetAiMateURLReq) (laosiji_app.GetAiMateURLResp, error)
	bringOut      func(context.Context, laosiji_app.AiMateBringOutReq) (laosiji_app.AiMateBringOutResp, error)
	debitAndLog   func(uint64, int64, time.Time) error
	creditAndLog  func(uint64, int64, float64, string, time.Time) error
	now           func() time.Time
}

func defaultTransferDependencies() transferDependencies {
	return transferDependencies{
		findLatest:    fundtransferlogmod.FindLatestByUIDAndCategory,
		findLatestOut: fundtransferlogmod.FindLatestOutByUIDAndCategory,
		getWallet:     walletmod.GetWallet,
		findUser:      usermod.FindUserByUID,
		getAuthURL:    laosiji_app.GetAiMateURL,
		bringOut:      laosiji_app.AiMateBringOut,
		debitAndLog:   debitAndLog,
		creditAndLog:  creditAndLog,
		now:           time.Now,
	}
}

func acquireLock(uid uint64) (func(), error) {
	if appg.Redis == nil {
		return nil, errors.New("redis is unavailable")
	}
	lock := redis.BuildLock(
		appg.Redis,
		redisconst.GetAiFundLockKey(uid),
		redsync.WithExpiry(aiFundLockExpiry),
		redsync.WithTries(1),
	)
	if err := lock.Lock(); err != nil {
		return nil, err
	}
	return func() {
		if _, err := lock.Unlock(); err != nil {
			log.Warn("unlock AI fund lock failed", log.Any("uid", uid), log.E(err))
		}
	}, nil
}

// GetAuthURL 先回收上一次第三方余额，再将主钱包金币上分并返回AI女友授权地址。
func GetAuthURL(ctx context.Context, uid uint64) (GetAuthURLResp, error) {
	unlock, err := acquireLock(uid)
	if err != nil {
		return GetAuthURLResp{}, errors.New("操作频繁，请稍后再试")
	}
	defer unlock()
	return getAuthURL(ctx, uid, defaultTransferDependencies())
}

func getAuthURL(ctx context.Context, uid uint64, deps transferDependencies) (GetAuthURLResp, error) {
	if err := settleDown(ctx, uid, deps); err != nil {
		return GetAuthURLResp{}, fmt.Errorf("下分失败: %w", err)
	}

	wallet, err := deps.getWallet(uid)
	if err != nil {
		return GetAuthURLResp{}, fmt.Errorf("获取钱包失败: %w", err)
	}
	var amount int64
	if wallet != nil {
		amount = wallet.Amount
	}

	var remainder float64
	lastOut, err := deps.findLatestOut(uid, fundtransferlogmod.CategoryAiGirlfriend)
	if err != nil {
		return GetAuthURLResp{}, fmt.Errorf("获取下分余数失败: %w", err)
	}
	if lastOut != nil {
		remainder = lastOut.Remainder
	}

	nickname, avatar := "用户", ""
	if user, findErr := deps.findUser(uid); findErr == nil && user != nil {
		if user.Name != "" {
			nickname = user.Name
		}
		avatar = user.Portrait
	}
	username := laosiji_app.GetUserName(appg.Conf.Base.Env, commod.KFK_APPID, uid)
	authResp, err := deps.getAuthURL(ctx, laosiji_app.GetAiMateURLReq{
		Username:   username,
		Nickname:   nickname,
		Asset:      assetAmount(amount, remainder),
		Currency:   "CNY",
		Theme:      "dark",
		UserAvatar: avatar,
	})
	if err != nil {
		return GetAuthURLResp{}, fmt.Errorf("获取AI女友地址失败: %w", err)
	}
	if authResp.AuthURL == "" {
		return GetAuthURLResp{}, errors.New("AI女友地址为空")
	}

	if amount > 0 {
		if err = deps.debitAndLog(uid, amount, deps.now()); err != nil {
			return GetAuthURLResp{}, fmt.Errorf("上分扣除金币失败: %w", err)
		}
	}
	return GetAuthURLResp{URL: authResp.AuthURL}, nil
}

// TrySettleDown 在钱包查询前尝试将AI女友剩余余额下分回主钱包。
func TrySettleDown(ctx context.Context, uid uint64) error {
	unlock, err := acquireLock(uid)
	if err != nil {
		return errors.New("操作频繁，请稍后再试")
	}
	defer unlock()
	return settleDown(ctx, uid, defaultTransferDependencies())
}

func settleDown(ctx context.Context, uid uint64, deps transferDependencies) error {
	latest, err := deps.findLatest(uid, fundtransferlogmod.CategoryAiGirlfriend)
	if err != nil {
		return err
	}
	if latest == nil || latest.FundType != fundtransferlogmod.FundTypeIn {
		return nil
	}

	resp, err := deps.bringOut(ctx, laosiji_app.AiMateBringOutReq{
		Username: laosiji_app.GetUserName(appg.Conf.Base.Env, commod.KFK_APPID, uid),
	})
	if err != nil {
		return err
	}
	returnAmount, remainder, err := balanceToWallet(resp.Balance)
	if err != nil {
		return err
	}
	desc := "AI女友下分"
	if returnAmount == 0 {
		desc += "-金币为0"
	}
	return deps.creditAndLog(uid, returnAmount, remainder, desc, deps.now())
}

func assetAmount(amount int64, remainder float64) string {
	amountDecimal := decimal.NewFromInt(amount).Div(decimal.NewFromInt(10))
	return amountDecimal.Add(decimal.NewFromFloat(remainder)).Round(2).StringFixed(2)
}

func balanceToWallet(balance string) (int64, float64, error) {
	value, err := decimal.NewFromString(balance)
	if err != nil {
		return 0, 0, fmt.Errorf("无效的第三方余额: %w", err)
	}
	if value.IsNegative() {
		return 0, 0, errors.New("第三方余额不能为负数")
	}
	coins := value.Mul(decimal.NewFromInt(10)).Floor()
	if coins.GreaterThan(decimal.NewFromInt(math.MaxInt64)) {
		return 0, 0, errors.New("第三方余额超出范围")
	}
	returnAmount := coins.IntPart()
	remainderDecimal := value.Sub(decimal.NewFromInt(returnAmount).Div(decimal.NewFromInt(10))).Round(2)
	remainder, _ := remainderDecimal.Float64()
	return returnAmount, remainder, nil
}

func debitAndLog(uid uint64, amount int64, now time.Time) error {
	if appg.VideoDB == nil {
		return errors.New("video database is unavailable")
	}
	return appg.VideoDB.Trans(func(t *db.MongoTool) error {
		wallet, err := walletmod.DebitAmount(t, amount, uid)
		if err != nil {
			return err
		}
		return fundtransferlogmod.Insert(t, &fundtransferlogmod.FundTransferLog{
			ID:        primitive.NewObjectID(),
			UID:       uid,
			Category:  fundtransferlogmod.CategoryAiGirlfriend,
			FundType:  fundtransferlogmod.FundTypeIn,
			Amount:    amount,
			Balance:   wallet.Amount,
			Desc:      "AI女友上分",
			CreatedAt: now,
		})
	})
}

func creditAndLog(uid uint64, amount int64, remainder float64, desc string, now time.Time) error {
	if appg.VideoDB == nil {
		return errors.New("video database is unavailable")
	}
	return appg.VideoDB.Trans(func(t *db.MongoTool) error {
		wallet, err := walletmod.CreditAmount(t, amount, uid)
		if err != nil {
			return err
		}
		return fundtransferlogmod.Insert(t, &fundtransferlogmod.FundTransferLog{
			ID:        primitive.NewObjectID(),
			UID:       uid,
			Category:  fundtransferlogmod.CategoryAiGirlfriend,
			FundType:  fundtransferlogmod.FundTypeOut,
			Amount:    amount,
			Balance:   wallet.Amount,
			Remainder: remainder,
			Desc:      desc,
			CreatedAt: now,
		})
	})
}