package handlers

import (
	"math"
	"net/http"
	"strconv"

	"oidc-oauth2-server/services"

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

type AdminHandler struct {
	adminService  *services.AdminService
	clientService *services.ClientService
}

func NewAdminHandler(adminService *services.AdminService, clientService *services.ClientService) *AdminHandler {
	return &AdminHandler{adminService: adminService, clientService: clientService}
}

func (h *AdminHandler) ShowAdminLogin(c *gin.Context) {
	c.HTML(http.StatusOK, "admin_login.html", gin.H{})
}

func (h *AdminHandler) HandleAdminLogin(c *gin.Context) {
	username := c.PostForm("username")
	password := c.PostForm("password")

	admin, err := h.adminService.Authenticate(username, password)
	if err != nil {
		c.HTML(http.StatusBadRequest, "admin_login.html", gin.H{
			"error": "Invalid credentials",
		})
		return
	}

	session := sessions.Default(c)
	session.Set("admin_id", admin.ID)
	session.Save()

	c.Redirect(http.StatusFound, "/admin/dashboard")
}

func (h *AdminHandler) Dashboard(c *gin.Context) {
	c.HTML(http.StatusOK, "admin_dashboard.html", gin.H{})
}

func (h *AdminHandler) ListUsers(c *gin.Context) {
	page, _ := strconv.Atoi(c.DefaultQuery("page", "1"))
	pageSize, _ := strconv.Atoi(c.DefaultQuery("page_size", "10"))

	users, total, err := h.adminService.ListUsers(page, pageSize)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.HTML(http.StatusOK, "admin_users.html", gin.H{
		"users":    users,
		"total":    total,
		"page":     page,
		"pageSize": pageSize,
	})
}

// ListClients 显示客户端列表页面
func (h *AdminHandler) ListClients(c *gin.Context) {
	page := 1
	pageSize := 10

	// 从查询参数获取分页信息
	if pageStr := c.Query("page"); pageStr != "" {
		if p, err := strconv.Atoi(pageStr); err == nil && p > 0 {
			page = p
		}
	}
	if pageSizeStr := c.Query("page_size"); pageSizeStr != "" {
		if ps, err := strconv.Atoi(pageSizeStr); err == nil && ps > 0 {
			pageSize = ps
		}
	}

	// 获取客户端列表
	clients, total, err := h.clientService.GetClients(page, pageSize)
	if err != nil {
		c.HTML(http.StatusInternalServerError, "error.html", gin.H{
			"error": err.Error(),
		})
		return
	}

	c.HTML(http.StatusOK, "admin_clients.html", gin.H{
		"clients":  clients,
		"page":     page,
		"pageSize": pageSize,
		"total":    total,
		"lastPage": int(math.Ceil(float64(total) / float64(pageSize))),
	})
}

// ShowCreateUser 显示创建用户页面
func (h *AdminHandler) ShowCreateUser(c *gin.Context) {
	c.HTML(http.StatusOK, "admin_create_user.html", gin.H{
		"title": "创建用户",
	})
}

// HandleCreateUser 处理创建用户请求
func (h *AdminHandler) HandleCreateUser(c *gin.Context) {
	username := c.PostForm("username")
	password := c.PostForm("password")
	email := c.PostForm("email")

	if username == "" || password == "" || email == "" {
		c.HTML(http.StatusBadRequest, "admin_create_user.html", gin.H{
			"title": "创建用户",
			"error": "用户名、密码和邮箱都不能为空",
		})
		return
	}

	_, err := h.adminService.CreateUser(username, password, email)
	if err != nil {
		c.HTML(http.StatusBadRequest, "admin_create_user.html", gin.H{
			"title": "创建用户",
			"error": "创建用户失败：" + err.Error(),
		})
		return
	}

	c.Redirect(http.StatusFound, "/admin/users")
}

// ShowEditUser 显示编辑用户页面
func (h *AdminHandler) ShowEditUser(c *gin.Context) {
	userID, err := strconv.ParseUint(c.Param("id"), 10, 32)
	if err != nil {
		c.HTML(http.StatusBadRequest, "error.html", gin.H{
			"error": "无效的用户ID",
		})
		return
	}

	user, err := h.adminService.GetUser(uint(userID))
	if err != nil {
		c.HTML(http.StatusNotFound, "error.html", gin.H{
			"error": "用户不存在",
		})
		return
	}

	c.HTML(http.StatusOK, "admin_edit_user.html", gin.H{
		"title": "编辑用户",
		"user":  user,
	})
}

// HandleEditUser 处理编辑用户请求
func (h *AdminHandler) HandleEditUser(c *gin.Context) {
	userID, err := strconv.ParseUint(c.Param("id"), 10, 32)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "无效的用户ID"})
		return
	}

	username := c.PostForm("username")
	email := c.PostForm("email")
	isActiveStr := c.PostForm("is_active")
	var isActive *bool
	if isActiveStr != "" {
		active := isActiveStr == "true"
		isActive = &active
	}

	_, err = h.adminService.UpdateUser(uint(userID), username, email, isActive)
	if err != nil {
		c.HTML(http.StatusBadRequest, "admin_edit_user.html", gin.H{
			"title": "编辑用户",
			"error": "更新用户失败：" + err.Error(),
		})
		return
	}

	// 如果提供了新密码，则更新密码
	newPassword := c.PostForm("password")
	if newPassword != "" {
		err = h.adminService.UpdateUserPassword(uint(userID), newPassword)
		if err != nil {
			c.HTML(http.StatusBadRequest, "admin_edit_user.html", gin.H{
				"title": "编辑用户",
				"error": "更新密码失败：" + err.Error(),
			})
			return
		}
	}

	c.Redirect(http.StatusFound, "/admin/users")
}

// HandleDeleteUser 处理删除用户请求
func (h *AdminHandler) HandleDeleteUser(c *gin.Context) {
	userID, err := strconv.ParseUint(c.Param("id"), 10, 32)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "无效的用户ID"})
		return
	}

	err = h.adminService.DeleteUser(uint(userID))
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "删除用户失败：" + err.Error()})
		return
	}

	c.Redirect(http.StatusFound, "/admin/users")
}