<?php

namespace BookStack\Http\Controllers\Api;

use BookStack\Entities\Models\Book;
use BookStack\Entities\Models\Chapter;
use BookStack\Entities\Models\Page;
use BookStack\Entities\Repos\PageRepo;
use BookStack\Exceptions\PermissionsException;
use Exception;
use Illuminate\Http\Request;

class PageApiController extends ApiController
{
    protected $pageRepo;

    protected $rules = [
        'create' => [
            'book_id' => 'required_unless:chapter_id|integer',
            'chapter_id' => 'required_unless:book_id|integer',
            'name' => 'required|string|max:255',
            'html' => 'required_without:markdown|string',
            'markdown' => 'required_without:html|string',
            'tags' => 'array',
        ],
        'update' => [
            'book_id' => 'required|integer',
            'chapter_id' => 'required|integer',
            'name' => 'string|min:1|max:255',
            'html' => 'string',
            'markdown' => 'string',
            'tags' => 'array',
        ],
    ];

    public function __construct(PageRepo $pageRepo)
    {
        $this->pageRepo = $pageRepo;
    }

    /**
     * Get a listing of pages visible to the user.
     */
    public function list()
    {
        $pages = Page::visible();
        return $this->apiListingResponse($pages, [
            'id', 'book_id', 'chapter_id', 'name', 'slug', 'priority',
            'draft', 'template',
            'created_at', 'updated_at', 'created_by', 'updated_by',
        ]);
    }

    /**
     * Create a new page in the system.
     */
    public function create(Request $request)
    {
        $this->validate($request, $this->rules['create']);

        if ($request->has('chapter_id')) {
            $parent = Chapter::visible()->findOrFail($request->get('chapter_id'));
        } else {
            $parent = Book::visible()->findOrFail($request->get('book_id'));
        }
        $this->checkOwnablePermission('page-create', $parent);

        $draft = $this->pageRepo->getNewDraftPage($parent);
        $this->pageRepo->publishDraft($draft, $request->only(array_keys($this->rules['create'])));

        return response()->json($draft->load(['tags']));
    }

    /**
     * View the details of a single page.
     */
    public function read(string $id)
    {
        $page = $this->pageRepo->getById($id, ['tags', 'createdBy', 'updatedBy']);
        return response()->json($page);
    }

    /**
     * Update the details of a single page.
     */
    public function update(Request $request, string $id)
    {
        $page = $this->pageRepo->getById($id, []);
        $this->checkOwnablePermission('page-update', $page);

        $parent = null;
        if ($request->has('chapter_id')) {
            $parent = Chapter::visible()->findOrFail($request->get('chapter_id'));
        } else if ($request->has('book_id')) {
            $parent = Book::visible()->findOrFail($request->get('book_id'));
        }

        if ($parent && !$parent->matches($page->getParent())) {
            $this->checkOwnablePermission('page-delete', $page);
            try {
                $this->pageRepo->move($page, $parent->getType() . ':' . $parent->id);
            } catch (Exception $exception) {
                if ($exception instanceof  PermissionsException) {
                    $this->showPermissionError();
                }

                return $this->jsonError(trans('errors.selected_book_chapter_not_found'));
            }
        }

        $updatedPage = $this->pageRepo->update($page, $request->all());
        return response()->json($updatedPage->load(['tags']));
    }

    /**
     * Delete a page from the system.
     */
    public function delete(string $id)
    {
        $page = $this->pageRepo->getById($id, []);
        $this->checkOwnablePermission('page-delete', $page);

        $this->pageRepo->destroy($page);
        return response('', 204);
    }
}