package rest

import (
	"encoding/json"
	"net/http"

	"github.com/gorilla/mux"
	"github.com/ocdp/cluster-service/internal/adapter/input/http/dto"
	"github.com/ocdp/cluster-service/internal/domain/entity"
	"github.com/ocdp/cluster-service/internal/domain/service"
)

// StorageHandler Storage Backend Handler
type StorageHandler struct {
	storageService *service.StorageService
}

// NewStorageHandler 创建 Storage Handler
func NewStorageHandler(storageService *service.StorageService) *StorageHandler {
	return &StorageHandler{
		storageService: storageService,
	}
}

// CreateStorage 创建存储后端
// @Summary 创建存储后端
// @Description 新增存储后端配置（NFS/PV/hostPath）
// @Tags Storage
// @Accept json
// @Produce json
// @Security BearerAuth
// @Param request body dto.CreateStorageRequest true "存储后端信息"
// @Success 201 {object} dto.StorageResponse
// @Failure 400 {object} dto.ErrorResponse
// @Router /storage-backends [post]
func (h *StorageHandler) CreateStorage(w http.ResponseWriter, r *http.Request) {
	var req dto.CreateStorageRequest
	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
		respondError(w, http.StatusBadRequest, "Invalid request body", err.Error())
		return
	}

	// 获取用户信息
	workspaceID := r.Header.Get("X-Workspace-ID")
	ownerID := r.Header.Get("X-User-ID")

	// 构建配置
	storageType := entity.StorageType(req.Type)
	config := entity.StorageConfig{}

	switch storageType {
	case entity.StorageTypeNFS:
		config.NFS = &entity.NFSConfig{
			Server: req.NFS.Server,
			Path:   req.NFS.Path,
		}
	case entity.StorageTypePV:
		config.PV = &entity.PVConfig{
			StorageClassName: req.PV.StorageClassName,
			Capacity:         req.PV.Capacity,
			AccessModes:      req.PV.AccessModes,
		}
	case entity.StorageTypeHostPath:
		config.HostPath = &entity.HostPathConfig{
			Path: req.HostPath.Path,
		}
	}

	// 调用领域服务
	storage, err := h.storageService.Create(
		r.Context(),
		workspaceID,
		ownerID,
		req.Name,
		storageType,
		config,
		req.Description,
		req.IsDefault,
		req.IsShared,
	)
	if err != nil {
		respondError(w, http.StatusBadRequest, "Failed to create storage backend", err.Error())
		return
	}

	// 返回响应
	response := toStorageResponse(storage)
	respondJSON(w, http.StatusCreated, response)
}

// GetStorage 获取存储后端详情
// @Summary 获取存储后端
// @Tags Storage
// @Produce json
// @Security BearerAuth
// @Param storage_id path string true "Storage ID"
// @Success 200 {object} dto.StorageResponse
// @Failure 404 {object} dto.ErrorResponse
// @Router /storage-backends/{storage_id} [get]
func (h *StorageHandler) GetStorage(w http.ResponseWriter, r *http.Request) {
	vars := mux.Vars(r)
	storageID := vars["storage_id"]

	storage, err := h.storageService.GetByID(r.Context(), storageID)
	if err != nil {
		respondError(w, http.StatusNotFound, "Storage backend not found", err.Error())
		return
	}

	response := toStorageResponse(storage)
	respondJSON(w, http.StatusOK, response)
}

// GetAllStorage 获取所有存储后端
// @Summary 列出所有存储后端
// @Tags Storage
// @Produce json
// @Security BearerAuth
// @Success 200 {array} dto.StorageResponse
// @Failure 500 {object} dto.ErrorResponse
// @Router /storage-backends [get]
func (h *StorageHandler) GetAllStorage(w http.ResponseWriter, r *http.Request) {
	// 获取 workspace_id（从 JWT）
	workspaceID := r.Header.Get("X-Workspace-ID")
	role := r.Header.Get("X-User-Role")

	var storages []*entity.StorageBackend
	var err error

	// Admin 可以看到所有，其他用户只看自己 workspace + 共享的
	if role == "admin" {
		storages, err = h.storageService.List(r.Context())
	} else if workspaceID != "" {
		// 获取 workspace 的存储 + 共享存储
		workspaceStorages, _ := h.storageService.GetByWorkspace(r.Context(), workspaceID)
		sharedStorages, _ := h.storageService.GetShared(r.Context())

		// 合并去重
		seen := make(map[string]bool)
		for _, s := range workspaceStorages {
			if !seen[s.ID] {
				storages = append(storages, s)
				seen[s.ID] = true
			}
		}
		for _, s := range sharedStorages {
			if !seen[s.ID] {
				storages = append(storages, s)
				seen[s.ID] = true
			}
		}
	} else {
		// 没有 workspace 的用户只能看到共享存储
		storages, err = h.storageService.GetShared(r.Context())
	}

	if err != nil {
		respondError(w, http.StatusInternalServerError, "Failed to list storage backends", err.Error())
		return
	}

	responses := make([]*dto.StorageResponse, 0, len(storages))
	for _, storage := range storages {
		responses = append(responses, toStorageResponse(storage))
	}

	respondJSON(w, http.StatusOK, responses)
}

// UpdateStorage 更新存储后端
// @Summary 更新存储后端
// @Tags Storage
// @Accept json
// @Produce json
// @Security BearerAuth
// @Param storage_id path string true "Storage ID"
// @Param request body dto.UpdateStorageRequest true "更新内容"
// @Success 200 {object} dto.StorageResponse
// @Failure 404 {object} dto.ErrorResponse
// @Router /storage-backends/{storage_id} [put]
func (h *StorageHandler) UpdateStorage(w http.ResponseWriter, r *http.Request) {
	vars := mux.Vars(r)
	storageID := vars["storage_id"]

	var req dto.UpdateStorageRequest
	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
		respondError(w, http.StatusBadRequest, "Invalid request body", err.Error())
		return
	}

	// 构建配置
	var storageType entity.StorageType
	if req.Type != "" {
		storageType = entity.StorageType(req.Type)
	}

	config := entity.StorageConfig{}
	if storageType == entity.StorageTypeNFS && (req.NFS.Server != "" || req.NFS.Path != "") {
		config.NFS = &entity.NFSConfig{
			Server: req.NFS.Server,
			Path:   req.NFS.Path,
		}
	} else if storageType == entity.StorageTypePV && req.PV.StorageClassName != "" {
		config.PV = &entity.PVConfig{
			StorageClassName: req.PV.StorageClassName,
			Capacity:         req.PV.Capacity,
			AccessModes:      req.PV.AccessModes,
		}
	} else if storageType == entity.StorageTypeHostPath && req.HostPath.Path != "" {
		config.HostPath = &entity.HostPathConfig{
			Path: req.HostPath.Path,
		}
	}

	storage, err := h.storageService.Update(
		r.Context(),
		storageID,
		req.Name,
		req.Description,
		storageType,
		config,
		req.IsDefault,
		req.IsShared,
	)
	if err != nil {
		respondError(w, http.StatusBadRequest, "Failed to update storage backend", err.Error())
		return
	}

	response := toStorageResponse(storage)
	respondJSON(w, http.StatusOK, response)
}

// DeleteStorage 删除存储后端
// @Summary 删除存储后端
// @Tags Storage
// @Produce json
// @Security BearerAuth
// @Param storage_id path string true "Storage ID"
// @Success 204 {string} string "No Content"
// @Failure 404 {object} dto.ErrorResponse
// @Router /storage-backends/{storage_id} [delete]
func (h *StorageHandler) DeleteStorage(w http.ResponseWriter, r *http.Request) {
	vars := mux.Vars(r)
	storageID := vars["storage_id"]

	if err := h.storageService.Delete(r.Context(), storageID); err != nil {
		respondError(w, http.StatusNotFound, "Failed to delete storage backend", err.Error())
		return
	}

	w.WriteHeader(http.StatusNoContent)
}

// toStorageResponse 转换为响应 DTO
func toStorageResponse(storage *entity.StorageBackend) *dto.StorageResponse {
	config := dto.StorageConfigDTO{}

	if storage.Config.NFS != nil {
		config.NFS = &dto.NFSConfigDTO{
			Server: storage.Config.NFS.Server,
			Path:   storage.Config.NFS.Path,
		}
	}
	if storage.Config.PV != nil {
		config.PV = &dto.PVConfigDTO{
			StorageClassName: storage.Config.PV.StorageClassName,
			Capacity:         storage.Config.PV.Capacity,
			AccessModes:      storage.Config.PV.AccessModes,
		}
	}
	if storage.Config.HostPath != nil {
		config.HostPath = &dto.HostPathConfigDTO{
			Path: storage.Config.HostPath.Path,
		}
	}

	return &dto.StorageResponse{
		ID:          storage.ID,
		WorkspaceID: storage.WorkspaceID,
		OwnerID:     storage.OwnerID,
		Name:        storage.Name,
		Type:        string(storage.Type),
		Config:      config,
		Description: storage.Description,
		IsDefault:   storage.IsDefault,
		IsShared:    storage.IsShared,
		CreatedAt:   storage.CreatedAt.Format("2006-01-02T15:04:05Z07:00"),
		UpdatedAt:   storage.UpdatedAt.Format("2006-01-02T15:04:05Z07:00"),
	}
}