package handlers

import (
	"net/http"
	"strconv"

	"ezops/internal/models"

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

// ApprovalHandler 审批处理器
type ApprovalHandler struct {
	db *gorm.DB
}

// NewApprovalHandler 创建审批处理器
func NewApprovalHandler(db *gorm.DB) *ApprovalHandler {
	return &ApprovalHandler{db: db}
}

// ListTemplates 获取审批模板列表
// @Summary 获取审批模板列表
// @Description 获取所有审批模板列表
// @Tags 审批流程
// @Produce json
// @Security Bearer
// @Param page query int false "页码"
// @Param page_size query int false "每页数量"
// @Success 200 {object} models.Response{data=models.ListResponse}
// @Router /approvals/templates [get]
func (h *ApprovalHandler) ListTemplates(c *gin.Context) {
	var query models.PageQuery
	c.ShouldBindQuery(&query)

	var total int64
	h.db.Model(&models.ApprovalTemplate{}).Count(&total)

	var templates []models.ApprovalTemplate
	h.db.Offset(query.GetOffset()).Limit(query.GetLimit()).Find(&templates)

	c.JSON(http.StatusOK, models.Response{
		Code:    200,
		Message: "success",
		Data: models.ListResponse{
			List:  templates,
			Total: total,
		},
	})
}

// GetTemplate 获取审批模板详情
// @Summary 获取审批模板详情
// @Description 获取指定审批模板的详细信息
// @Tags 审批流程
// @Produce json
// @Security Bearer
// @Param id path int true "模板ID"
// @Success 200 {object} models.Response{data=models.ApprovalTemplate}
// @Router /approvals/templates/{id} [get]
func (h *ApprovalHandler) GetTemplate(c *gin.Context) {
	id, _ := strconv.Atoi(c.Param("id"))

	var template models.ApprovalTemplate
	if err := h.db.First(&template, id).Error; err != nil {
		c.JSON(http.StatusNotFound, models.Response{
			Code:    404,
			Message: "模板不存在",
		})
		return
	}

	c.JSON(http.StatusOK, models.Response{
		Code:    200,
		Message: "success",
		Data:    template,
	})
}

// CreateTemplate 创建审批模板
// @Summary 创建审批模板
// @Description 创建新审批模板
// @Tags 审批流程
// @Accept json
// @Produce json
// @Security Bearer
// @Param request body models.CreateApprovalTemplateRequest true "创建请求"
// @Success 200 {object} models.Response{data=models.ApprovalTemplate}
// @Router /approvals/templates [post]
func (h *ApprovalHandler) CreateTemplate(c *gin.Context) {
	var req models.CreateApprovalTemplateRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, models.Response{
			Code:    400,
			Message: "请求参数错误: " + err.Error(),
		})
		return
	}

	template := models.ApprovalTemplate{
		Name:        req.Name,
		Code:        req.Code,
		Description: req.Description,
		Type:        req.Type,
		FormSchema:  req.FormSchema,
		FlowConfig:  req.FlowConfig,
		Enabled:     true,
	}

	if err := h.db.Create(&template).Error; err != nil {
		c.JSON(http.StatusInternalServerError, models.Response{
			Code:    500,
			Message: "创建失败",
		})
		return
	}

	c.JSON(http.StatusOK, models.Response{
		Code:    200,
		Message: "创建成功",
		Data:    template,
	})
}

// UpdateTemplate 更新审批模板
// @Summary 更新审批模板
// @Description 更新指定审批模板
// @Tags 审批流程
// @Accept json
// @Produce json
// @Security Bearer
// @Param id path int true "模板ID"
// @Param request body models.CreateApprovalTemplateRequest true "更新请求"
// @Success 200 {object} models.Response{data=models.ApprovalTemplate}
// @Router /approvals/templates/{id} [put]
func (h *ApprovalHandler) UpdateTemplate(c *gin.Context) {
	id, _ := strconv.Atoi(c.Param("id"))

	var req models.CreateApprovalTemplateRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, models.Response{
			Code:    400,
			Message: "请求参数错误: " + err.Error(),
		})
		return
	}

	var template models.ApprovalTemplate
	if err := h.db.First(&template, id).Error; err != nil {
		c.JSON(http.StatusNotFound, models.Response{
			Code:    404,
			Message: "模板不存在",
		})
		return
	}

	updates := map[string]interface{}{
		"name":        req.Name,
		"description": req.Description,
		"type":        req.Type,
		"form_schema": req.FormSchema,
		"flow_config": req.FlowConfig,
	}

	if err := h.db.Model(&template).Updates(updates).Error; err != nil {
		c.JSON(http.StatusInternalServerError, models.Response{
			Code:    500,
			Message: "更新失败",
		})
		return
	}

	h.db.First(&template, id)

	c.JSON(http.StatusOK, models.Response{
		Code:    200,
		Message: "更新成功",
		Data:    template,
	})
}

// DeleteTemplate 删除审批模板
// @Summary 删除审批模板
// @Description 删除指定审批模板
// @Tags 审批流程
// @Produce json
// @Security Bearer
// @Param id path int true "模板ID"
// @Success 200 {object} models.Response
// @Router /approvals/templates/{id} [delete]
func (h *ApprovalHandler) DeleteTemplate(c *gin.Context) {
	id, _ := strconv.Atoi(c.Param("id"))

	if err := h.db.Delete(&models.ApprovalTemplate{}, id).Error; err != nil {
		c.JSON(http.StatusInternalServerError, models.Response{
			Code:    500,
			Message: "删除失败",
		})
		return
	}

	c.JSON(http.StatusOK, models.Response{
		Code:    200,
		Message: "删除成功",
	})
}

// ListProcesses 获取审批流程列表
// @Summary 获取审批流程列表
// @Description 获取所有审批流程列表
// @Tags 审批流程
// @Produce json
// @Security Bearer
// @Param page query int false "页码"
// @Param page_size query int false "每页数量"
// @Param status query string false "状态过滤"
// @Success 200 {object} models.Response{data=models.ListResponse}
// @Router /approvals/processes [get]
func (h *ApprovalHandler) ListProcesses(c *gin.Context) {
	var query models.PageQuery
	c.ShouldBindQuery(&query)

	db := h.db.Model(&models.ApprovalProcess{}).Preload("Template").Preload("ApplicantUser")

	// 状态过滤
	if status := c.Query("status"); status != "" {
		db = db.Where("status = ?", status)
	}

	var total int64
	db.Count(&total)

	var processes []models.ApprovalProcess
	db.Order("created_at DESC").
		Offset(query.GetOffset()).
		Limit(query.GetLimit()).
		Find(&processes)

	c.JSON(http.StatusOK, models.Response{
		Code:    200,
		Message: "success",
		Data: models.ListResponse{
			List:  processes,
			Total: total,
		},
	})
}

// GetProcess 获取审批流程详情
// @Summary 获取审批流程详情
// @Description 获取指定审批流程的详细信息
// @Tags 审批流程
// @Produce json
// @Security Bearer
// @Param id path int true "流程ID"
// @Success 200 {object} models.Response{data=models.ApprovalProcess}
// @Router /approvals/processes/{id} [get]
func (h *ApprovalHandler) GetProcess(c *gin.Context) {
	id, _ := strconv.Atoi(c.Param("id"))

	var process models.ApprovalProcess
	if err := h.db.Preload("Template").Preload("ApplicantUser").Preload("Steps.ApproverUser").First(&process, id).Error; err != nil {
		c.JSON(http.StatusNotFound, models.Response{
			Code:    404,
			Message: "流程不存在",
		})
		return
	}

	c.JSON(http.StatusOK, models.Response{
		Code:    200,
		Message: "success",
		Data:    process,
	})
}

// CreateProcess 创建审批流程
// @Summary 创建审批流程
// @Description 创建新审批流程
// @Tags 审批流程
// @Accept json
// @Produce json
// @Security Bearer
// @Param request body models.CreateApprovalProcessRequest true "创建请求"
// @Success 200 {object} models.Response{data=models.ApprovalProcess}
// @Router /approvals/processes [post]
func (h *ApprovalHandler) CreateProcess(c *gin.Context) {
	var req models.CreateApprovalProcessRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, models.Response{
			Code:    400,
			Message: "请求参数错误: " + err.Error(),
		})
		return
	}

	// 获取模板
	var template models.ApprovalTemplate
	if err := h.db.First(&template, req.TemplateID).Error; err != nil {
		c.JSON(http.StatusNotFound, models.Response{
			Code:    404,
			Message: "模板不存在",
		})
		return
	}

	process := models.ApprovalProcess{
		TemplateID:  req.TemplateID,
		Title:       req.Title,
		FormData:    req.FormData,
		Status:      "pending",
		CurrentStep: 0,
		TotalSteps:  1, // 简化处理
	}

	if err := h.db.Create(&process).Error; err != nil {
		c.JSON(http.StatusInternalServerError, models.Response{
			Code:    500,
			Message: "创建失败",
		})
		return
	}

	h.db.Preload("Template").First(&process, process.ID)

	c.JSON(http.StatusOK, models.Response{
		Code:    200,
		Message: "创建成功",
		Data:    process,
	})
}

// ApproveProcess 审批通过
// @Summary 审批通过
// @Description 审批通过指定流程
// @Tags 审批流程
// @Accept json
// @Produce json
// @Security Bearer
// @Param id path int true "流程ID"
// @Param request body models.ApproveRequest true "审批请求"
// @Success 200 {object} models.Response{data=models.ApprovalProcess}
// @Router /approvals/processes/{id}/approve [post]
func (h *ApprovalHandler) ApproveProcess(c *gin.Context) {
	id, _ := strconv.Atoi(c.Param("id"))

	var req models.ApproveRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, models.Response{
			Code:    400,
			Message: "请求参数错误",
		})
		return
	}

	var process models.ApprovalProcess
	if err := h.db.First(&process, id).Error; err != nil {
		c.JSON(http.StatusNotFound, models.Response{
			Code:    404,
			Message: "流程不存在",
		})
		return
	}

	process.Status = "approved"
	// now := time.Now()
	// process.ApprovedAt = &now

	if err := h.db.Save(&process).Error; err != nil {
		c.JSON(http.StatusInternalServerError, models.Response{
			Code:    500,
			Message: "审批失败",
		})
		return
	}

	c.JSON(http.StatusOK, models.Response{
		Code:    200,
		Message: "审批通过",
		Data:    process,
	})
}

// RejectProcess 审批拒绝
// @Summary 审批拒绝
// @Description 审批拒绝指定流程
// @Tags 审批流程
// @Accept json
// @Produce json
// @Security Bearer
// @Param id path int true "流程ID"
// @Param request body models.ApproveRequest true "审批请求"
// @Success 200 {object} models.Response{data=models.ApprovalProcess}
// @Router /approvals/processes/{id}/reject [post]
func (h *ApprovalHandler) RejectProcess(c *gin.Context) {
	id, _ := strconv.Atoi(c.Param("id"))

	var req models.ApproveRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, models.Response{
			Code:    400,
			Message: "请求参数错误",
		})
		return
	}

	var process models.ApprovalProcess
	if err := h.db.First(&process, id).Error; err != nil {
		c.JSON(http.StatusNotFound, models.Response{
			Code:    404,
			Message: "流程不存在",
		})
		return
	}

	process.Status = "rejected"
	process.RejectReason = req.Comment
	// now := time.Now()
	// process.RejectedAt = &now

	if err := h.db.Save(&process).Error; err != nil {
		c.JSON(http.StatusInternalServerError, models.Response{
			Code:    500,
			Message: "拒绝失败",
		})
		return
	}

	c.JSON(http.StatusOK, models.Response{
		Code:    200,
		Message: "已拒绝",
		Data:    process,
	})
}