// Path: Backend/internal/httpx/api_project_decode.go

package httpx

import (
	"encoding/json"
	"errors"
	"io"
	"net/http"
	"strings"
)

type createProjectFolderRequest struct {
	Name             string `json:"name"`
	ParentFolderPath string `json:"parentFolderId"`
}

type renameProjectFolderRequest struct {
	FolderPath string `json:"folderId"`
	Name       string `json:"name"`
}

type deleteProjectFolderRequest struct {
	FolderPath string `json:"folderId"`
}

// Keep the existing JSON contract for the frontend, but use clearer path-vs-stable-ID
// names internally so the move flow is easier to reason about.
type moveProjectFolderRequest struct {
	FolderPath       string `json:"folderId"`
	FolderStableID   string `json:"folderNodeId"`
	ParentFolderPath string `json:"parentFolderId"`
	ParentStableID   string `json:"parentNodeId"`
	TargetIndex      int    `json:"targetIndex"`
}

type createProjectItemRequest struct {
	Name             string `json:"name"`
	ParentFolderPath string `json:"parentFolderId"`
	ItemType         string `json:"itemType"`
}

type deleteProjectItemRequest struct {
	ItemPath string `json:"itemId"`
}

type moveProjectItemRequest struct {
	ItemPath         string `json:"itemId"`
	ItemStableID     string `json:"itemNodeId"`
	ParentFolderPath string `json:"parentFolderId"`
	ParentStableID   string `json:"parentNodeId"`
	TargetIndex      int    `json:"targetIndex"`
}

func decodeMoveProjectFolderRequest(w http.ResponseWriter, r *http.Request) (moveProjectFolderRequest, bool) {
	var payload moveProjectFolderRequest
	if !decodeJSONObjectBody(w, r, &payload) {
		return payload, false
	}
	return payload, true
}

func decodeDeleteProjectFolderRequest(r *http.Request) deleteProjectFolderRequest {
	return deleteProjectFolderRequest{
		FolderPath: strings.TrimSpace(r.URL.Query().Get("folderId")),
	}
}

func decodeDeleteProjectItemRequest(r *http.Request) deleteProjectItemRequest {
	return deleteProjectItemRequest{
		ItemPath: strings.TrimSpace(r.URL.Query().Get("itemId")),
	}
}

func decodeRenameProjectFolderRequest(w http.ResponseWriter, r *http.Request) (renameProjectFolderRequest, bool) {
	var payload renameProjectFolderRequest
	if !decodeJSONObjectBody(w, r, &payload) {
		return payload, false
	}
	return payload, true
}

func decodeProjectFolderRequest(w http.ResponseWriter, r *http.Request) (createProjectFolderRequest, bool) {
	var payload createProjectFolderRequest
	if !decodeJSONObjectBody(w, r, &payload) {
		return payload, false
	}
	return payload, true
}

func decodeProjectItemRequest(w http.ResponseWriter, r *http.Request) (createProjectItemRequest, bool) {
	var payload createProjectItemRequest
	if !decodeJSONObjectBody(w, r, &payload) {
		return payload, false
	}
	return payload, true
}

func decodeMoveProjectItemRequest(w http.ResponseWriter, r *http.Request) (moveProjectItemRequest, bool) {
	var payload moveProjectItemRequest
	if !decodeJSONObjectBody(w, r, &payload) {
		return payload, false
	}
	return payload, true
}

func decodeJSONObjectBody(w http.ResponseWriter, r *http.Request, target any) bool {
	decoder := json.NewDecoder(r.Body)
	decoder.DisallowUnknownFields()

	if err := decoder.Decode(target); err != nil {
		if errors.Is(err, io.EOF) {
			WriteError(w, http.StatusBadRequest, RequestIDFromContext(r.Context()), "invalid_json", "The request body is required and must be valid JSON.")
			return false
		}

		WriteError(w, http.StatusBadRequest, RequestIDFromContext(r.Context()), "invalid_json", "The request body must be valid JSON.")
		return false
	}

	if err := decoder.Decode(&struct{}{}); !errors.Is(err, io.EOF) {
		WriteError(w, http.StatusBadRequest, RequestIDFromContext(r.Context()), "invalid_json", "The request body must contain a single JSON object.")
		return false
	}

	return true
}