package handler

import (
	"encoding/json"
	"net/http"
	"net/url"
	"strconv"
	"strings"
	"time"

	"kra/internal/server/httpx"
	"kra/internal/service"
	"kra/internal/service/dto"

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

type Export struct {
	system  *service.SystemService
	service *service.ExportService
}

func NewExport(system *service.SystemService, service *service.ExportService) *Export {
	return &Export{system: system, service: service}
}

type exportToken struct {
	TemplateID string            `json:"templateID"`
	Params     map[string]string `json:"params"`
	Blank      bool              `json:"blank"`
}

func exportParams(values url.Values) map[string]string {
	out := map[string]string{}
	nested, _ := url.ParseQuery(values.Get("params"))
	for key, items := range nested {
		if len(items) > 0 {
			out[key] = items[0]
		}
	}
	for key, items := range values {
		if key != "params" && len(items) > 0 {
			out[key] = items[0]
		}
	}
	return out
}

func (h *Export) Create(c *gin.Context) {
	var req dto.ExportTemplateRequest
	if c.ShouldBindJSON(&req) != nil || req.Name == "" || req.TemplateID == "" {
		httpx.Fail(c, "参数错误")
		return
	}
	if err := h.service.CreateRequest(c.Request.Context(), &req); err != nil {
		httpx.Fail(c, "创建失败:"+err.Error())
		return
	}
	httpx.OK(c)
}
func (h *Export) Update(c *gin.Context) {
	var req dto.ExportTemplateRequest
	if c.ShouldBindJSON(&req) != nil || req.ID == 0 {
		httpx.Fail(c, "参数错误")
		return
	}
	if err := h.service.UpdateRequest(c.Request.Context(), &req); err != nil {
		httpx.Fail(c, "更新失败:"+err.Error())
		return
	}
	httpx.OK(c)
}
func (h *Export) Delete(c *gin.Context) {
	var req dto.IDRequest
	if c.ShouldBindJSON(&req) != nil {
		httpx.Fail(c, "参数错误")
		return
	}
	if err := h.service.Delete(c.Request.Context(), []uint{req.ID}); err != nil {
		httpx.Fail(c, "删除失败")
		return
	}
	httpx.OK(c)
}
func (h *Export) DeleteMany(c *gin.Context) {
	var req dto.IDsRequest
	if c.ShouldBindJSON(&req) != nil {
		httpx.Fail(c, "参数错误")
		return
	}
	if err := h.service.Delete(c.Request.Context(), req.IDs); err != nil {
		httpx.Fail(c, "删除失败")
		return
	}
	httpx.OK(c)
}
func (h *Export) Find(c *gin.Context) {
	id, _ := strconv.ParseUint(c.Query("ID"), 10, 64)
	item, err := h.service.Template(c.Request.Context(), uint(id), "")
	if err != nil {
		httpx.Fail(c, "查询失败")
		return
	}
	httpx.Write(c, httpx.CodeSuccess, gin.H{"resysExportTemplate": item}, "查询成功")
}
func (h *Export) List(c *gin.Context) {
	p, size := page(c)
	start, startErr := parseTime(c.Query("startCreatedAt"))
	end, endErr := parseTime(c.Query("endCreatedAt"))
	if startErr != nil || endErr != nil {
		httpx.Fail(c, "参数错误")
		return
	}
	items, total, err := h.service.TemplatesFilter(c.Request.Context(), p, size, c.Query("name"), c.Query("tableName"), c.Query("templateID"), start, end)
	if err != nil {
		httpx.Fail(c, "获取失败")
		return
	}
	httpx.Write(c, httpx.CodeSuccess, httpx.PageResult{List: items, Total: total, Page: p, PageSize: size}, "获取成功")
}
func (h *Export) Preview(c *gin.Context) {
	sql, err := h.service.Preview(c.Request.Context(), c.Query("templateID"), exportParams(c.Request.URL.Query()))
	if err != nil {
		httpx.Fail(c, "预览失败:"+err.Error())
		return
	}
	httpx.Write(c, httpx.CodeSuccess, gin.H{"sql": sql}, "获取成功")
}

func (h *Export) Issue(blank bool) gin.HandlerFunc {
	return func(c *gin.Context) {
		templateID := c.Query("templateID")
		if templateID == "" {
			httpx.Fail(c, "模板ID不能为空")
			return
		}
		token := strings.ReplaceAll(uuid.NewString(), "-", "")
		raw, _ := json.Marshal(exportToken{TemplateID: templateID, Params: exportParams(c.Request.URL.Query()), Blank: blank})
		if err := h.system.CacheSet(c.Request.Context(), "export:"+token, string(raw), 5*time.Minute); err != nil {
			httpx.Fail(c, "导出令牌创建失败")
			return
		}
		httpx.Write(c, httpx.CodeSuccess, gin.H{"token": token}, "获取成功")
	}
}

func (h *Export) Import(c *gin.Context) {
	file, err := c.FormFile("file")
	if err != nil {
		httpx.Fail(c, "请选择导入文件")
		return
	}
	opened, err := file.Open()
	if err != nil {
		httpx.Fail(c, "读取文件失败")
		return
	}
	defer opened.Close()
	templateID := c.PostForm("templateID")
	if templateID == "" {
		templateID = c.Query("templateID")
	}
	if err = h.service.Import(c.Request.Context(), templateID, opened); err != nil {
		httpx.Fail(c, err.Error())
		return
	}
	httpx.OK(c)
}

func (h *Export) Download(expectBlank bool) gin.HandlerFunc {
	return func(c *gin.Context) {
		token := c.Query("token")
		raw, ok, err := h.system.CacheGet(c.Request.Context(), "export:"+token)
		if err != nil || !ok {
			httpx.Fail(c, "导出令牌无效或已过期")
			return
		}
		_ = h.system.CacheDelete(c.Request.Context(), "export:"+token)
		var value exportToken
		if json.Unmarshal([]byte(raw), &value) != nil || value.Blank != expectBlank {
			httpx.Fail(c, "导出令牌无效")
			return
		}
		var data []byte
		var name string
		if expectBlank {
			data, name, err = h.service.ExportBlankTemplate(c.Request.Context(), value.TemplateID)
		} else {
			data, name, err = h.service.Export(c.Request.Context(), value.TemplateID, value.Params)
		}
		if err != nil {
			httpx.Fail(c, "导出失败:"+err.Error())
			return
		}
		c.Header("Content-Disposition", "attachment; filename*=UTF-8''"+url.QueryEscape(name))
		c.Data(http.StatusOK, "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet", data)
	}
}