package handler

import (
	"dd_fiber_api/internal/question"
	"dd_fiber_api/internal/question/service"

	"github.com/gofiber/fiber/v2"
)

// KnowledgeTreeHandler 知识树处理器
type KnowledgeTreeHandler struct {
	knowledgeTreeService *service.KnowledgeTreeService
}

// NewKnowledgeTreeHandler 创建知识树处理器
func NewKnowledgeTreeHandler(knowledgeTreeService *service.KnowledgeTreeService) *KnowledgeTreeHandler {
	return &KnowledgeTreeHandler{
		knowledgeTreeService: knowledgeTreeService,
	}
}

// CreateKnowledgeTreeNode 创建知识树节点
func (h *KnowledgeTreeHandler) CreateKnowledgeTreeNode(c *fiber.Ctx) error {
	var req service.CreateKnowledgeTreeNodeRequest
	if err := c.BodyParser(&req); err != nil {
		return c.Status(fiber.StatusBadRequest).JSON(fiber.Map{
			"success": false,
			"message": "请求参数解析失败: " + err.Error(),
		})
	}

	if req.Title == "" {
		return c.Status(fiber.StatusBadRequest).JSON(fiber.Map{
			"success": false,
			"message": "节点标题不能为空",
		})
	}

	if req.Type == "" {
		return c.Status(fiber.StatusBadRequest).JSON(fiber.Map{
			"success": false,
			"message": "知识树类型不能为空",
		})
	}

	if req.Type != question.KnowledgeTreeTypeObjective && req.Type != question.KnowledgeTreeTypeSubjective {
		return c.Status(fiber.StatusBadRequest).JSON(fiber.Map{
			"success": false,
			"message": "知识树类型无效，必须是 objective 或 subjective",
		})
	}

	node, err := h.knowledgeTreeService.CreateKnowledgeTreeNode(&req)
	if err != nil {
		return c.Status(fiber.StatusInternalServerError).JSON(fiber.Map{
			"success": false,
			"message": err.Error(),
		})
	}

	return c.JSON(fiber.Map{
		"success": true,
		"message": "创建成功",
		"node":    node,
	})
}

// GetKnowledgeTreeNode 获取知识树节点
func (h *KnowledgeTreeHandler) GetKnowledgeTreeNode(c *fiber.Ctx) error {
	id := c.Query("id")
	if id == "" {
		return c.Status(fiber.StatusBadRequest).JSON(fiber.Map{
			"success": false,
			"message": "节点ID不能为空",
		})
	}

	node, err := h.knowledgeTreeService.GetKnowledgeTreeNode(id)
	if err != nil {
		return c.Status(fiber.StatusNotFound).JSON(fiber.Map{
			"success": false,
			"message": err.Error(),
		})
	}

	return c.JSON(fiber.Map{
		"success": true,
		"message": "获取成功",
		"node":    node,
	})
}

// GetAllKnowledgeTreeNodes 获取所有知识树节点（扁平列表）
func (h *KnowledgeTreeHandler) GetAllKnowledgeTreeNodes(c *fiber.Ctx) error {
	treeTypeStr := c.Query("type", "")
	if treeTypeStr == "" {
		return c.Status(fiber.StatusBadRequest).JSON(fiber.Map{
			"success": false,
			"message": "知识树类型不能为空",
		})
	}

	treeType := question.KnowledgeTreeType(treeTypeStr)
	if treeType != question.KnowledgeTreeTypeObjective && treeType != question.KnowledgeTreeTypeSubjective {
		return c.Status(fiber.StatusBadRequest).JSON(fiber.Map{
			"success": false,
			"message": "知识树类型无效，必须是 objective 或 subjective",
		})
	}

	nodes, err := h.knowledgeTreeService.GetAllKnowledgeTreeNodes(treeType)
	if err != nil {
		return c.Status(fiber.StatusInternalServerError).JSON(fiber.Map{
			"success": false,
			"message": err.Error(),
		})
	}

	return c.JSON(fiber.Map{
		"success": true,
		"message": "获取成功",
		"nodes":   nodes,
	})
}

// GetKnowledgeTreeByParentID 根据父节点ID获取子节点列表
func (h *KnowledgeTreeHandler) GetKnowledgeTreeByParentID(c *fiber.Ctx) error {
	parentID := c.Query("parent_id", "") // 空字符串表示根节点
	treeTypeStr := c.Query("type", "")
	if treeTypeStr == "" {
		return c.Status(fiber.StatusBadRequest).JSON(fiber.Map{
			"success": false,
			"message": "知识树类型不能为空",
		})
	}

	treeType := question.KnowledgeTreeType(treeTypeStr)
	if treeType != question.KnowledgeTreeTypeObjective && treeType != question.KnowledgeTreeTypeSubjective {
		return c.Status(fiber.StatusBadRequest).JSON(fiber.Map{
			"success": false,
			"message": "知识树类型无效，必须是 objective 或 subjective",
		})
	}

	nodes, err := h.knowledgeTreeService.GetKnowledgeTreeByParentID(parentID, treeType)
	if err != nil {
		return c.Status(fiber.StatusInternalServerError).JSON(fiber.Map{
			"success": false,
			"message": err.Error(),
		})
	}

	return c.JSON(fiber.Map{
		"success": true,
		"message": "获取成功",
		"nodes":   nodes,
	})
}

// GetKnowledgeTree 获取完整树形结构
func (h *KnowledgeTreeHandler) GetKnowledgeTree(c *fiber.Ctx) error {
	treeTypeStr := c.Query("type", "")
	if treeTypeStr == "" {
		return c.Status(fiber.StatusBadRequest).JSON(fiber.Map{
			"success": false,
			"message": "知识树类型不能为空",
		})
	}

	treeType := question.KnowledgeTreeType(treeTypeStr)
	if treeType != question.KnowledgeTreeTypeObjective && treeType != question.KnowledgeTreeTypeSubjective {
		return c.Status(fiber.StatusBadRequest).JSON(fiber.Map{
			"success": false,
			"message": "知识树类型无效，必须是 objective 或 subjective",
		})
	}

	tree, err := h.knowledgeTreeService.GetKnowledgeTree(treeType)
	if err != nil {
		return c.Status(fiber.StatusInternalServerError).JSON(fiber.Map{
			"success": false,
			"message": err.Error(),
		})
	}

	return c.JSON(fiber.Map{
		"success": true,
		"message": "获取成功",
		"tree":    tree,
	})
}

// UpdateKnowledgeTreeNode 更新知识树节点
func (h *KnowledgeTreeHandler) UpdateKnowledgeTreeNode(c *fiber.Ctx) error {
	var req service.UpdateKnowledgeTreeNodeRequest
	if err := c.BodyParser(&req); err != nil {
		return c.Status(fiber.StatusBadRequest).JSON(fiber.Map{
			"success": false,
			"message": "请求参数解析失败: " + err.Error(),
		})
	}

	if req.ID == "" {
		return c.Status(fiber.StatusBadRequest).JSON(fiber.Map{
			"success": false,
			"message": "节点ID不能为空",
		})
	}

	if req.Title == "" {
		return c.Status(fiber.StatusBadRequest).JSON(fiber.Map{
			"success": false,
			"message": "节点标题不能为空",
		})
	}

	err := h.knowledgeTreeService.UpdateKnowledgeTreeNode(&req)
	if err != nil {
		return c.Status(fiber.StatusInternalServerError).JSON(fiber.Map{
			"success": false,
			"message": err.Error(),
		})
	}

	return c.JSON(fiber.Map{
		"success": true,
		"message": "更新成功",
	})
}

// DeleteKnowledgeTreeNode 删除知识树节点
func (h *KnowledgeTreeHandler) DeleteKnowledgeTreeNode(c *fiber.Ctx) error {
	id := c.Params("id")
	if id == "" {
		return c.Status(fiber.StatusBadRequest).JSON(fiber.Map{
			"success": false,
			"message": "节点ID不能为空",
		})
	}

	err := h.knowledgeTreeService.DeleteKnowledgeTreeNode(id)
	if err != nil {
		return c.Status(fiber.StatusInternalServerError).JSON(fiber.Map{
			"success": false,
			"message": err.Error(),
		})
	}

	return c.JSON(fiber.Map{
		"success": true,
		"message": "删除成功",
	})
}