package handler

import (
	"errors"
	"time"

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

	"git.sundynix.cn/Blizzard/sundynix-site/server/internal/model"
	"git.sundynix.cn/Blizzard/sundynix-site/server/internal/pkg/req"
	"git.sundynix.cn/Blizzard/sundynix-site/server/internal/pkg/resp"
)

// AdminPostHandler 管理端文章 CRUD（含草稿）。
type AdminPostHandler struct {
	db *gorm.DB
}

func NewAdminPostHandler(db *gorm.DB) *AdminPostHandler {
	return &AdminPostHandler{db: db}
}

type postForm struct {
	Slug      string `json:"slug" binding:"required"`
	Title     string `json:"title" binding:"required"`
	Category  string `json:"category"`
	Summary   string `json:"summary"`
	Content   string `json:"content"`
	Published bool   `json:"published"`
}

// List GET /api/admin/posts — 分页 + 关键词，含草稿
func (h *AdminPostHandler) List(c *gin.Context) {
	var q req.PageQuery
	if err := c.ShouldBindQuery(&q); err != nil {
		resp.BadRequest(c, "分页参数不合法")
		return
	}
	q.Normalize()

	tx := h.db.Model(&model.Post{})
	if q.Keyword != "" {
		kw := "%" + q.Keyword + "%"
		tx = tx.Where("title LIKE ? OR slug LIKE ? OR category LIKE ?", kw, kw, kw)
	}

	var total int64
	if err := tx.Count(&total).Error; err != nil {
		resp.ServerError(c, "查询失败")
		return
	}
	var items []model.PostListItem
	err := tx.Order("created_at DESC").
		Offset(q.Offset()).Limit(q.PageSize).
		Find(&items).Error
	if err != nil {
		resp.ServerError(c, "查询失败")
		return
	}
	resp.Page(c, items, total, q.Page, q.PageSize)
}

// Get GET /api/admin/posts/:id
func (h *AdminPostHandler) Get(c *gin.Context) {
	var post model.Post
	err := h.db.First(&post, "id = ?", c.Param("id")).Error
	if errors.Is(err, gorm.ErrRecordNotFound) {
		resp.NotFound(c, "文章不存在")
		return
	}
	if err != nil {
		resp.ServerError(c, "查询失败")
		return
	}
	resp.OK(c, post)
}

// Create POST /api/admin/posts
func (h *AdminPostHandler) Create(c *gin.Context) {
	var form postForm
	if err := c.ShouldBindJSON(&form); err != nil {
		resp.BadRequest(c, "slug 和标题不能为空")
		return
	}
	post := model.Post{
		Slug:     form.Slug,
		Title:    form.Title,
		Category: form.Category,
		Summary:  form.Summary,
		Content:  form.Content,
	}
	if form.Published {
		now := time.Now()
		post.PublishedAt = &now
	}
	if err := h.db.Create(&post).Error; err != nil {
		if errors.Is(err, gorm.ErrDuplicatedKey) {
			resp.BadRequest(c, "slug 已存在")
			return
		}
		resp.ServerError(c, "创建失败："+err.Error())
		return
	}
	resp.OK(c, post)
}

// Update PUT /api/admin/posts/:id
func (h *AdminPostHandler) Update(c *gin.Context) {
	var form postForm
	if err := c.ShouldBindJSON(&form); err != nil {
		resp.BadRequest(c, "slug 和标题不能为空")
		return
	}
	var post model.Post
	err := h.db.First(&post, "id = ?", c.Param("id")).Error
	if errors.Is(err, gorm.ErrRecordNotFound) {
		resp.NotFound(c, "文章不存在")
		return
	}
	if err != nil {
		resp.ServerError(c, "查询失败")
		return
	}

	post.Slug = form.Slug
	post.Title = form.Title
	post.Category = form.Category
	post.Summary = form.Summary
	post.Content = form.Content
	// 发布状态切换：首次发布记时间，撤回清空，重复发布保留原时间
	if form.Published && post.PublishedAt == nil {
		now := time.Now()
		post.PublishedAt = &now
	} else if !form.Published {
		post.PublishedAt = nil
	}

	if err := h.db.Save(&post).Error; err != nil {
		resp.ServerError(c, "更新失败："+err.Error())
		return
	}
	resp.OK(c, post)
}

// Delete DELETE /api/admin/posts/:id
func (h *AdminPostHandler) Delete(c *gin.Context) {
	res := h.db.Delete(&model.Post{}, "id = ?", c.Param("id"))
	if res.Error != nil {
		resp.ServerError(c, "删除失败")
		return
	}
	if res.RowsAffected == 0 {
		resp.NotFound(c, "文章不存在")
		return
	}
	resp.OK(c, nil)
}