package handler

import (
	"fmt"
	"net/http"
	"time"

	"soul-api/internal/database"
	"soul-api/internal/model"
	"soul-api/internal/wechat"

	"github.com/gin-gonic/gin"
)

// AdminWithdrawalsList GET /api/admin/withdrawals
func AdminWithdrawalsList(c *gin.Context) {
	statusFilter := c.Query("status")
	var list []model.Withdrawal
	q := database.DB().Order("created_at DESC").Limit(100)
	if statusFilter != "" {
		q = q.Where("status = ?", statusFilter)
	}
	if err := q.Find(&list).Error; err != nil {
		c.JSON(http.StatusOK, gin.H{"success": false, "error": err.Error(), "withdrawals": []interface{}{}, "stats": gin.H{"total": 0}})
		return
	}
	userIds := make([]string, 0, len(list))
	seen := make(map[string]bool)
	for _, w := range list {
		if !seen[w.UserID] {
			seen[w.UserID] = true
			userIds = append(userIds, w.UserID)
		}
	}
	var users []model.User
	if len(userIds) > 0 {
		database.DB().Where("id IN ?", userIds).Find(&users)
	}
	userMap := make(map[string]*model.User)
	for i := range users {
		userMap[users[i].ID] = &users[i]
	}
	withdrawals := make([]gin.H, 0, len(list))
	for _, w := range list {
		u := userMap[w.UserID]
		userName := "未知用户"
		var userAvatar *string
		account := "未绑定微信号"
		if w.WechatID != nil && *w.WechatID != "" {
			account = *w.WechatID
		}
		if u != nil {
			if u.Nickname != nil {
				userName = *u.Nickname
			}
			userAvatar = u.Avatar
			if u.WechatID != nil && *u.WechatID != "" {
				account = *u.WechatID
			}
		}
		st := "pending"
		if w.Status != nil {
			st = *w.Status
			if st == "success" {
				st = "completed"
			} else if st == "failed" {
				st = "rejected"
			} else if st == "pending_confirm" {
				st = "pending_confirm"
			}
		}
		withdrawals = append(withdrawals, gin.H{
			"id": w.ID, "userId": w.UserID, "userName": userName, "userAvatar": userAvatar,
			"amount": w.Amount, "status": st, "createdAt": w.CreatedAt,
			"method": "wechat", "account": account,
		})
	}
	c.JSON(http.StatusOK, gin.H{"success": true, "withdrawals": withdrawals, "stats": gin.H{"total": len(withdrawals)}})
}

// AdminWithdrawalsAction PUT /api/admin/withdrawals 审核/打款
// approve：先调微信转账接口打款，成功则标为 processing，失败则标为 failed 并返回错误。
// 若未初始化微信转账客户端，则仅将状态标为 success（线下打款后批准）。
// reject：直接标为 failed。
func AdminWithdrawalsAction(c *gin.Context) {
	var body struct {
		ID           string `json:"id"`
		Action       string `json:"action"`
		ErrorMessage string `json:"errorMessage"`
		Reason       string `json:"reason"`
	}
	if err := c.ShouldBindJSON(&body); err != nil || body.ID == "" {
		c.JSON(http.StatusOK, gin.H{"success": false, "error": "缺少 id 或请求体无效"})
		return
	}
	reason := body.ErrorMessage
	if reason == "" {
		reason = body.Reason
	}
	if reason == "" && body.Action == "reject" {
		reason = "管理员拒绝"
	}

	db := database.DB()
	now := time.Now()

	switch body.Action {
	case "reject":
		err := db.Model(&model.Withdrawal{}).Where("id = ?", body.ID).Updates(map[string]interface{}{
			"status":         "failed",
			"error_message":  reason,
			"fail_reason":    reason,
			"processed_at":   now,
		}).Error
		if err != nil {
			c.JSON(http.StatusOK, gin.H{"success": false, "error": err.Error()})
			return
		}
		c.JSON(http.StatusOK, gin.H{"success": true, "message": "已拒绝"})
		return

	case "approve":
		var w model.Withdrawal
		if err := db.Where("id = ?", body.ID).First(&w).Error; err != nil {
			c.JSON(http.StatusOK, gin.H{"success": false, "error": "提现记录不存在"})
			return
		}
		st := ""
		if w.Status != nil {
			st = *w.Status
		}
		if st != "pending" && st != "processing" && st != "pending_confirm" {
			c.JSON(http.StatusOK, gin.H{"success": false, "error": "当前状态不允许批准"})
			return
		}

		openID := ""
		if w.WechatOpenid != nil && *w.WechatOpenid != "" {
			openID = *w.WechatOpenid
		}
		if openID == "" {
			var u model.User
			if err := db.Where("id = ?", w.UserID).First(&u).Error; err == nil && u.OpenID != nil {
				openID = *u.OpenID
			}
		}
		if openID == "" {
			c.JSON(http.StatusOK, gin.H{"success": false, "error": "用户未绑定微信 openid，无法打款"})
			return
		}

		// 调用微信转账接口；未初始化时仅标记为已打款（线下打款）
		outBatchNo := wechat.GenerateTransferBatchNo()
		outDetailNo := wechat.GenerateTransferDetailNo()
		remark := "提现"
		if w.Remark != nil && *w.Remark != "" {
			remark = *w.Remark
		}
		amountFen := int(w.Amount * 100)
		if amountFen < 1 {
			c.JSON(http.StatusOK, gin.H{"success": false, "error": "提现金额异常"})
			return
		}
		params := wechat.TransferParams{
			OutBatchNo:  outBatchNo,
			OutDetailNo: outDetailNo,
			OpenID:      openID,
			Amount:      amountFen,
			Remark:      remark,
			BatchName:   "用户提现",
			BatchRemark: fmt.Sprintf("用户 %s 提现 %.2f 元", w.UserID, w.Amount),
		}

		result, err := wechat.InitiateTransfer(params)
		if err != nil {
			// 未初始化转账客户端：仅标记为 success，提示线下打款
			if err.Error() == "转账客户端未初始化" {
				_ = db.Model(&w).Updates(map[string]interface{}{
					"status":       "success",
					"processed_at": now,
				}).Error
				c.JSON(http.StatusOK, gin.H{
					"success": true,
					"message": "已标记为已打款。当前未接入微信转账，请线下打款。",
				})
				return
			}
			// 其他打款失败：记失败原因
			failMsg := err.Error()
			_ = db.Model(&w).Updates(map[string]interface{}{
				"status":        "failed",
				"fail_reason":   failMsg,
				"error_message": failMsg,
				"processed_at":  now,
			}).Error
			c.JSON(http.StatusOK, gin.H{
				"success": false,
				"error":   "发起打款失败",
				"message": failMsg,
			})
			return
		}

		// 打款已受理，更新为处理中并保存微信批次号
		processingStatus := "processing"
		batchID := result.BatchID
		_ = db.Model(&w).Updates(map[string]interface{}{
			"status":       processingStatus,
			"batch_no":     outBatchNo,
			"detail_no":    outDetailNo,
			"batch_id":     batchID,
			"processed_at": now,
		}).Error
		c.JSON(http.StatusOK, gin.H{
			"success": true,
			"message": "已发起打款，微信处理中",
			"data":    gin.H{"batch_id": batchID},
		})
		return

	default:
		c.JSON(http.StatusOK, gin.H{"success": false, "error": "action 须为 approve 或 reject"})
	}
}