package handlers

import (
	"net/http"
	"strings"

	"stock-user-system/internal/datasource"
	"stock-user-system/internal/models"

	"github.com/gin-gonic/gin"
	"gorm.io/gorm"
	"gorm.io/gorm/clause"
)

var validExchanges = map[string]string{
	"SSE":  "上交所",
	"SZSE": "深交所",
	"BSE":  "北交所",
}

func toModelStock(s datasource.StockBasic) models.Stock {
	return models.Stock{
		TsCode:     s.TsCode,
		Symbol:     s.Symbol,
		Name:       s.Name,
		Area:       s.Area,
		Industry:   s.Industry,
		Fullname:   s.Fullname,
		Enname:     s.Enname,
		Cnspell:    s.Cnspell,
		Market:     s.Market,
		Exchange:   s.Exchange,
		CurrType:   s.CurrType,
		ListStatus: s.ListStatus,
		ListDate:   s.ListDate,
		DelistDate: s.DelistDate,
		IsHs:       s.IsHs,
		ActName:    s.ActName,
		ActEntType: s.ActEntType,
	}
}

// DataSyncHandler 处理数据同步相关接口。
type DataSyncHandler struct {
	DB     *gorm.DB
	client *datasource.Client
}

// NewDataSyncHandler 创建数据同步处理器。
func NewDataSyncHandler(db *gorm.DB) *DataSyncHandler {
	return &DataSyncHandler{
		DB:     db,
		client: datasource.NewClient(),
	}
}

type initStocksResponse struct {
	Count   int    `json:"count"`
	Message string `json:"message"`
}

// InitStocks 从 Tushare 拉取全部上市股票列表并写入数据库。
func (h *DataSyncHandler) InitStocks(c *gin.Context) {
	stocks, err := h.client.ListStocks()
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"success": false, "error": err.Error()})
		return
	}

	records := make([]models.Stock, 0, len(stocks))
	for _, s := range stocks {
		records = append(records, toModelStock(s))
	}

	if err := h.DB.Exec("TRUNCATE TABLE stocks RESTART IDENTITY").Error; err != nil {
		if !strings.Contains(err.Error(), "does not exist") {
			c.JSON(http.StatusInternalServerError, gin.H{"success": false, "error": "清空旧数据失败: " + err.Error()})
			return
		}
	}

	if err := h.DB.CreateInBatches(records, 500).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"success": false, "error": "写入股票列表失败: " + err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{
		"success": true,
		"data": initStocksResponse{
			Count:   len(records),
			Message: "股票列表初始化完成",
		},
	})
}

type syncStocksByExchangeResponse struct {
	Exchange string `json:"exchange"`
	Count    int    `json:"count"`
	Message  string `json:"message"`
}

// SyncStocksByExchange 按交易所从 Tushare 同步股票基础信息。
func (h *DataSyncHandler) SyncStocksByExchange(c *gin.Context) {
	exchange := strings.ToUpper(strings.TrimSpace(c.Param("exchange")))
	if _, ok := validExchanges[exchange]; !ok {
		c.JSON(http.StatusBadRequest, gin.H{"success": false, "error": "无效的交易所代码，支持 SSE/SZSE/BSE"})
		return
	}

	stocks, err := h.client.ListStocksByExchange(exchange)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"success": false, "error": err.Error()})
		return
	}

	records := make([]models.Stock, 0, len(stocks))
	for _, s := range stocks {
		records = append(records, toModelStock(s))
	}

	if err := h.DB.Clauses(clause.OnConflict{
		Columns:   []clause.Column{{Name: "ts_code"}},
		UpdateAll: true,
	}).CreateInBatches(records, 500).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"success": false, "error": "写入股票列表失败: " + err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{
		"success": true,
		"data": syncStocksByExchangeResponse{
			Exchange: exchange,
			Count:    len(records),
			Message:  validExchanges[exchange] + "股票同步完成",
		},
	})
}