<?php

namespace App\Services;

use App\Exceptions\SubmissionException;
use App\Helpers\EntryHelpers;
use App\Http\Requests\StoreEntryRequest;
use App\Models\Author;
use App\Models\Entry;
use App\Models\EntryFile;
use App\Models\EntryGallery;
use App\Models\EntryHash;
use App\Models\Game;
use App\Models\Genre;
use App\Models\Language;
use App\Models\Modification;
use App\Models\Platform;
use Illuminate\Support\Facades\Cache;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Facades\Storage;

/**
 * @phpstan-import-type FSFileData from \App\Types\FSTypes
 */
class SubmissionsService {

    /**
     * Request for store/edit.
     * @var StoreEntryRequest|null
     */
    private ?StoreEntryRequest $request = null;

    /**
     * Section for store/edit.
     * @var string|null
     */
    private ?string $section = null;

    /**
     * @return list<FSFileData>
     */
    public function prepareOldFiles( ?Entry $entry = null ): array
    {
        if( $entry === null ){
            $files = old( 'files_uuid', [] );
        } else {
            $files = old( 'files_uuid', $entry->files->pluck('file_uuid')->toArray() );
        }

        if( $files === [] )
            return [];

        return array_map(
            function( string $uuid ) {
                $file = EntryFile::where('file_uuid', $uuid)->first();

                if( $file )
                    return [
                        'name' => $file->filename,
                        'totalChunks' => 0, // Already uploaded.
                        'rawFile' => null,
                        'progressValue' => 0,
                        'currentChunk' => 0,
                        'done' => true,
                        'error' => null,
                        'uuid' => $uuid
                    ];

                $file = Cache::get("uploaded_file_{$uuid}");
                if( $file )
                    return [
                        'name' => $file['filename'],
                        'totalChunks' => 0, // Already uploaded.
                        'rawFile' => null,
                        'progressValue' => 0,
                        'currentChunk' => 0,
                        'done' => true,
                        'error' => null,
                        'uuid' => $uuid
                    ];

                return null;
             },
        $files );
    }

    /**
     * @param StoreEntryRequest $request
     * @param string $section
     *
     * @return Entry
     * @throws SubmissionException
     * @throws \Throwable
     */
    public function storeEntry( StoreEntryRequest $request, string $section ){

        // STEP 1 : Prepare basic fields.

        $this->request = $request;
        $this->section = $section;
        $user_id = 0; // TODO: Replace that.

        $entry = DB::transaction(function () use ( $user_id ) {

            // STEP 2 : Create game.

            $gameId = null;
            if( section_must_be( ['romhacks', 'translations'], $this->section ) ){
                $gameId = $this->Step2_CreateAndReturnGameId();
            }

            // STEP 3 : Create Complete title.
            $completeTitle = $this->Step3_BuildCompleteTitle( $gameId );

            // STEP 4 : Generate slug and entry title.
            $entrySlug = EntryHelpers::uniqueSlug( $completeTitle, Entry::class );

            if( section_must_be( 'translations', $this->section ) &&
                !$this->request->input('entry_title') ){
                $entryTitle = Game::find($gameId)->name;
            } else {
                $entryTitle = $this->request->input('entry_title');
            }

            // STEP 5 : Removed / Delayed.
            // $mainImage = $this->Step5_MoveMainImage();

            // STEP 6 : Prepare entry fields and save entry.
            $fields = [
                'type' => $this->section,
                'title' => $entryTitle,
                'slug' => $entrySlug,
                'description' => $this->request->input('description'),
                'main_image' => $this->request->input('main-image'),
                'state' => $this->request->input('submit-state'),
                'game_id' => $gameId,
                'status_id' => $this->request->input('status'),
                'version' => $this->request->input('version'),
                'release_date' => $this->request->input('release-date'),
                'staff_credits' => $this->request->input('staff_credits'),
                'relevant_link' => $this->request->input('release_site'),
                'youtube_link' => $this->request->input('youtube_video'),
                'user_id' => $user_id,
                'complete_title' => $completeTitle,
            ];

            $entry = Entry::create( $fields );

            // STEP 7 : Save entry fields.
            $this->Step7_SaveEntryFiles( $entry->id );

            // STEP 8 : Save hashes.
            $this->Step8_SaveHashes( $entry->id );

            // STEP 9 : Save Authors.
            $this->Step9_SaveAuthors( $entry );

            // STEP 10 : Save Modifications.
            if( section_must_be( 'romhacks', $this->section ) ){
                $this->Step10_SaveRomhacksModifications( $entry );
            }

            // STEP 11 : Save Languages
            $this->Step11_SaveLanguages( $entry );

            // STEP 12 : Prepare Gallery images.
            $this->Step12a_PrepareGalleryImages( $entry );

            return $entry;

        });

        // Step 12, Move main image and gallery.
        $this->Step12b_MoveMainImage( $entry );
        $this->Step12c_SaveGalleryImages( $entry );

        return $entry;

    }

    /**
     * @return int
     *
     * @throws SubmissionException
     */
    private function Step2_CreateAndReturnGameId(): int {

        // Already existing game.
        if( $this->request->input('game_id') )
            return $this->request->input('game_id');

        // Need to create a game.
        if( !$this->request->input('new-game-title') || !$this->request->input('new-game-platform') || !$this->request->input('new-game-genre') )
            throw new SubmissionException( "New game informations is missing" );

        $platform = Platform::find( $this->request->input('new-game-platform') );
        $genre = Genre::find( $this->request->input('new-game-genre') );

        if( !$platform || !$genre )
            throw new SubmissionException( "Incorrect game platform id" );

        $gameSlug = EntryHelpers::uniqueSlug( $this->request->input('new-game-title'), Game::class );

        $game = Game::create([
            'name' => trim( $this->request->input('new-game-title') ),
            'slug' => $gameSlug,
            'platform_id' => $platform->id,
            'genre_id' => $genre->id,
        ]);

        return $game->id;
    }

    /**
     * Prepare and build complete title.
     *
     * @param int|null $gameId
     *
     * @return string
     */
    private function Step3_BuildCompleteTitle( ?int $gameId = null ): string {
        $fields = [];

        $fields['entry_title'] = $this->request->input('entry_title') ?? null;
        if( section_must_be( [ 'homebrew', 'translations' ], $this->section ) && $gameId ){
            $fields['game_name'] = Game::find( $gameId )->name;
        }
        if( section_must_be( 'translations', $this->section ) ) {
            $fields['languages_string'] = Language::whereIn('id', $this->request->input('languages', []))->pluck('name')->implode(', ');
        }
        if( section_must_be(['romhacks', 'homebrew', 'lua-scripts', 'tutorials'], $this->section ) ) {
            // TODO: Add single platform ID compatibility.
            $fields['platform_name'] = Game::find( $gameId )->platform->name;
        }

        return EntryHelpers::buildCompleteTitle( $this->section, $fields );
    }

    /**
     * @param int $entryId
     *
     * @return void
     * @throws SubmissionException
     */
    private function Step7_SaveEntryFiles( int $entryId ): void
    {
        foreach ( $this->request->input('files_uuid', [] ) as $uuid ) {
            $fileData = Cache::pull("uploaded_file_{$uuid}");
            if( !$fileData )
                throw new SubmissionException( "File {$uuid} has expired. Please delete all your files and retry." );

            EntryFile::create([
                'entry_id' => $entryId,
                'file_uuid' => $uuid,
                'filename' => $fileData['filename'],
                'filepath' => $fileData['filepath'],
                'favorite_server' => $fileData['favorite_server'],
                'favorite_at' => \DateTimeImmutable::createFromTimestamp( $fileData['favorite_at'] ),
                'filesize' => $fileData['filesize'],
                'state' => 'public'
            ]);

        }
    }

    /**
     * @param int $entryId
     *
     * @return void
     */
    private function Step8_SaveHashes( int $entryId ): void
    {
        foreach ( $this->request->input('hashes', [] ) as $hash ) {
            if( !isset($hash['filename'], $hash['hash_crc32'], $hash['hash_sha1'], $hash['verified']) ) {
                continue;
            }

            EntryHash::create([
               'entry_id' => $entryId,
               'filename' => $hash['filename'],
               'hash_crc32' => $hash['hash_crc32'],
               'hash_sha1' => $hash['hash_sha1'],
               'verified' => $hash['verified'],
            ]);
        }
    }

    /**
     * @param Entry $entry
     *
     * @return void
     * @throws SubmissionException
     */
    private function Step9_SaveAuthors( Entry $entry ): void
    {
        // Existing authors.
        foreach ( $this->request->input('authors', [] ) as $authorId ) {
            $author = Author::find( $authorId );
            if( !$author )
                throw new SubmissionException( "Author {$authorId} does not exist." );
            $entry->authors()->attach( $author->id );
        }

        // New Authors
        foreach ( $this->request->input('new-authors', [] ) as $authorName ) {
            $authorName = trim( $authorName );
            if( $authorName === '' )
                continue;

            $author = Author::firstOrCreate(
               ['slug' => EntryHelpers::uniqueSlug( $authorName, Author::class )],
               ['name' => $authorName]
            );
            $entry->authors()->attach( $author->id );
        }
    }

    /**
     * @param Entry $entry
     *
     * @return void
     * @throws SubmissionException
     */
    private function Step10_SaveRomhacksModifications( Entry $entry ): void
    {
        foreach ( $this->request->input('modifications', [] ) as $modificationId ) {
            $modification = Modification::find( $modificationId );
            if( !$modification )
                throw new SubmissionException( "Modification {$modificationId} does not exist." );
            $entry->modifications()->attach( $modification->id );
        }
    }

    /**
     * @param Entry $entry
     *
     * @return void
     * @throws SubmissionException
     */
    private function Step11_SaveLanguages( Entry $entry ): void
    {
        foreach ( $this->request->input('languages', [] ) as $languageId ) {
            $language = Language::find( $languageId );
            if( !$language )
                throw new SubmissionException( "Language {$languageId} does not exist." );
            $entry->languages()->attach( $language->id );
        }

    }

    private function Step12a_PrepareGalleryImages( Entry $entry ): void
    {
        foreach ( $this->request->input('gallery', [] ) as $imagePath ) {
            EntryGallery::create([
                'entry_id' => $entry->id,
                'image' => $imagePath,
            ]);
        }
    }

    /**
     * @param Entry $entry
     *
     * @return void
     */
    private function Step12b_MoveMainImage( Entry $entry ): void {
        $mainImage = $entry->main_image;
        $newPath = 'entries/main-images/' . basename($mainImage);

        if( !Storage::disk('public')->move($mainImage, $newPath) )
            return;

        $entry->update(['main_image' => $newPath]);
    }

    private function Step12c_SaveGalleryImages( Entry $entry ): void
    {
        foreach ( $entry->gallery as $galleryItem ) {
            $newPath = 'entries/gallery-images/' . $entry->id . '/' . basename($galleryItem->image);

            if( !Storage::disk('public')->move($galleryItem->image, $newPath) )
                continue;

            $galleryItem->update(['image' => $newPath]);
        }
    }

}