package handlers

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

	"gitea.hostxtra.co.uk/mrhid6/notely/backend/internal/interfaces/middleware"
	"github.com/gorilla/mux"
	"go.mongodb.org/mongo-driver/v2/bson"

	"gitea.hostxtra.co.uk/mrhid6/notely/backend/internal/application/dto"
	"gitea.hostxtra.co.uk/mrhid6/notely/backend/internal/application/services"
)

// AdminHandler handles admin-level HTTP requests
type AdminHandler struct {
	adminService *services.AdminService
}

// NewAdminHandler creates a new AdminHandler
func NewAdminHandler(adminService *services.AdminService) *AdminHandler {
	return &AdminHandler{adminService: adminService}
}

// ListUsers handles GET /admin/users
func (h *AdminHandler) ListUsers(w http.ResponseWriter, r *http.Request) {
	users, err := h.adminService.ListUsers(r.Context())
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}
	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(map[string]interface{}{"users": users})
}

// DeleteUser handles DELETE /admin/users/{userId}
func (h *AdminHandler) DeleteUser(w http.ResponseWriter, r *http.Request) {
	targetUserID, err := bson.ObjectIDFromHex(mux.Vars(r)["userId"])
	if err != nil {
		http.Error(w, "invalid user id", http.StatusBadRequest)
		return
	}

	currentUserIDHex, err := middleware.GetUserIDFromContext(r.Context())
	if err != nil {
		http.Error(w, "unauthorized", http.StatusUnauthorized)
		return
	}
	currentUserID, err := bson.ObjectIDFromHex(currentUserIDHex)
	if err != nil {
		http.Error(w, "unauthorized", http.StatusUnauthorized)
		return
	}

	if err := h.adminService.DeleteUser(r.Context(), currentUserID, targetUserID); err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	w.WriteHeader(http.StatusNoContent)
}

// UpdateUserGroups handles PUT /admin/users/{userId}/groups
func (h *AdminHandler) UpdateUserGroups(w http.ResponseWriter, r *http.Request) {
	userID, err := bson.ObjectIDFromHex(mux.Vars(r)["userId"])
	if err != nil {
		http.Error(w, "invalid user id", http.StatusBadRequest)
		return
	}

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

	groupIDs := make([]bson.ObjectID, 0, len(req.GroupIDs))
	for _, groupID := range req.GroupIDs {
		parsed, err := bson.ObjectIDFromHex(groupID)
		if err != nil {
			http.Error(w, "invalid group id", http.StatusBadRequest)
			return
		}
		groupIDs = append(groupIDs, parsed)
	}

	user, err := h.adminService.UpdateUserGroups(r.Context(), userID, groupIDs)
	if err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(user)
}

// DeleteGroup handles DELETE /admin/groups/{groupId}
func (h *AdminHandler) DeleteGroup(w http.ResponseWriter, r *http.Request) {
	groupID, err := bson.ObjectIDFromHex(mux.Vars(r)["groupId"])
	if err != nil {
		http.Error(w, "invalid group id", http.StatusBadRequest)
		return
	}

	if err := h.adminService.DeleteGroup(r.Context(), groupID); err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	w.WriteHeader(http.StatusNoContent)
}

// ListGroups handles GET /admin/groups
func (h *AdminHandler) ListGroups(w http.ResponseWriter, r *http.Request) {
	groups, err := h.adminService.ListGroups(r.Context())
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}
	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(map[string]interface{}{"groups": groups})
}

// CreateGroup handles POST /admin/groups
func (h *AdminHandler) CreateGroup(w http.ResponseWriter, r *http.Request) {
	var req dto.CreatePermissionGroupRequest
	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
		http.Error(w, "invalid request body", http.StatusBadRequest)
		return
	}

	group, err := h.adminService.CreateGroup(r.Context(), &req)
	if err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	w.Header().Set("Content-Type", "application/json")
	w.WriteHeader(http.StatusCreated)
	json.NewEncoder(w).Encode(group)
}

// UpdateGroup handles PUT /admin/groups/{groupId}
func (h *AdminHandler) UpdateGroup(w http.ResponseWriter, r *http.Request) {
	groupID, err := bson.ObjectIDFromHex(mux.Vars(r)["groupId"])
	if err != nil {
		http.Error(w, "invalid group id", http.StatusBadRequest)
		return
	}

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

	group, err := h.adminService.UpdateGroup(r.Context(), groupID, &req)
	if err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(group)
}

// ListAllSpaces handles GET /admin/spaces
func (h *AdminHandler) ListAllSpaces(w http.ResponseWriter, r *http.Request) {
	spaces, err := h.adminService.ListAllSpaces(r.Context())
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}
	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(map[string]interface{}{"spaces": spaces})
}

// UpdateSpace handles PUT /admin/spaces/{spaceId}
func (h *AdminHandler) UpdateSpace(w http.ResponseWriter, r *http.Request) {
	spaceID, err := bson.ObjectIDFromHex(mux.Vars(r)["spaceId"])
	if err != nil {
		http.Error(w, "invalid space id", http.StatusBadRequest)
		return
	}

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

	space, err := h.adminService.UpdateSpace(r.Context(), spaceID, &req)
	if err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(space)
}

// SetSpaceVisibility handles PUT /admin/spaces/{spaceId}/visibility
func (h *AdminHandler) SetSpaceVisibility(w http.ResponseWriter, r *http.Request) {
	spaceID, err := bson.ObjectIDFromHex(mux.Vars(r)["spaceId"])
	if err != nil {
		http.Error(w, "invalid space id", http.StatusBadRequest)
		return
	}
	var req struct {
		IsPublic bool `json:"is_public"`
	}
	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
		http.Error(w, "invalid request body", http.StatusBadRequest)
		return
	}
	if err := h.adminService.SetSpaceVisibility(r.Context(), spaceID, req.IsPublic); err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}
	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(map[string]string{"message": "visibility updated"})
}

// AddSpaceMember handles POST /admin/spaces/{spaceId}/members
func (h *AdminHandler) AddSpaceMember(w http.ResponseWriter, r *http.Request) {
	spaceID, err := bson.ObjectIDFromHex(mux.Vars(r)["spaceId"])
	if err != nil {
		http.Error(w, "invalid space id", http.StatusBadRequest)
		return
	}

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

	userID, err := bson.ObjectIDFromHex(req.UserID)
	if err != nil {
		http.Error(w, "invalid user id", http.StatusBadRequest)
		return
	}

	if err := h.adminService.AddSpaceMember(r.Context(), spaceID, userID); err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	w.Header().Set("Content-Type", "application/json")
	w.WriteHeader(http.StatusCreated)
	json.NewEncoder(w).Encode(map[string]string{"message": "member added"})
}

// ListSpaceMembers handles GET /admin/spaces/{spaceId}/members
func (h *AdminHandler) ListSpaceMembers(w http.ResponseWriter, r *http.Request) {
	spaceID, err := bson.ObjectIDFromHex(mux.Vars(r)["spaceId"])
	if err != nil {
		http.Error(w, "invalid space id", http.StatusBadRequest)
		return
	}

	members, err := h.adminService.ListSpaceMembers(r.Context(), spaceID)
	if err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(map[string]interface{}{"members": members})
}

// RemoveSpaceMember handles DELETE /admin/spaces/{spaceId}/members/{userId}
func (h *AdminHandler) RemoveSpaceMember(w http.ResponseWriter, r *http.Request) {
	spaceID, err := bson.ObjectIDFromHex(mux.Vars(r)["spaceId"])
	if err != nil {
		http.Error(w, "invalid space id", http.StatusBadRequest)
		return
	}

	userID, err := bson.ObjectIDFromHex(mux.Vars(r)["userId"])
	if err != nil {
		http.Error(w, "invalid user id", http.StatusBadRequest)
		return
	}

	if err := h.adminService.RemoveSpaceMember(r.Context(), spaceID, userID); err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	w.WriteHeader(http.StatusNoContent)
}

// DeleteSpace handles DELETE /admin/spaces/{spaceId}
func (h *AdminHandler) DeleteSpace(w http.ResponseWriter, r *http.Request) {
	spaceID, err := bson.ObjectIDFromHex(mux.Vars(r)["spaceId"])
	if err != nil {
		http.Error(w, "invalid space id", http.StatusBadRequest)
		return
	}

	if err := h.adminService.DeleteSpace(r.Context(), spaceID); err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	w.WriteHeader(http.StatusNoContent)
}

// GetFeatureFlags handles GET /admin/feature-flags
func (h *AdminHandler) GetFeatureFlags(w http.ResponseWriter, r *http.Request) {
	flags, err := h.adminService.GetFeatureFlags(r.Context())
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(flags)
}

// UpdateFeatureFlags handles PUT /admin/feature-flags
func (h *AdminHandler) UpdateFeatureFlags(w http.ResponseWriter, r *http.Request) {
	var req dto.UpdateFeatureFlagsRequest
	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
		http.Error(w, "invalid request body", http.StatusBadRequest)
		return
	}

	flags, err := h.adminService.UpdateFeatureFlags(r.Context(), &req)
	if err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(flags)
}

// DeleteProvider handles DELETE /admin/auth/providers/{providerId}
func (h *AdminHandler) DeleteProvider(w http.ResponseWriter, r *http.Request) {
	providerID, err := bson.ObjectIDFromHex(mux.Vars(r)["providerId"])
	if err != nil {
		http.Error(w, "invalid provider id", http.StatusBadRequest)
		return
	}

	if err := h.adminService.DeleteProvider(r.Context(), providerID); err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	w.WriteHeader(http.StatusNoContent)
}