<?php

namespace App\Http\Controllers;

use App\Models\Language;
use App\Models\Post;
use App\Models\PostTranslation;
use Barryvdh\DomPDF\Facade\Pdf;
use Illuminate\Support\Carbon;
use Illuminate\Support\Facades\App;
use Illuminate\Support\Facades\Auth;

class PostController extends Controller
{

    public function showById($id)
    {
        $post =
            Post::with([
            'postable' => function ($query) {
                $query->select(['id', 'name']);
            },
            'category' => function ($query) {
                $query->with('translations');
            },
            'translations' => function ($query) {
                $query
                ->where('locale', App::getLocale());
                // ->whereDate('from', '<=', now())    //TODO: Exclude date queries ONLY for post Admins!
                // ->where( function($query) {
                //     $query->whereDate('till', '>', now())->orWhereNull('till');
                // })
            },
            ])
            ->where('id', $id)
            ->firstOrFail();

        // Poll posts have their own page
        if (\App\Models\Poll::where('post_id', $post->id)->exists()) {
            $slug = $post->translations->first()?->slug ?? PostTranslation::where('post_id', $post->id)->value('slug');
            if ($slug) {
                return redirect()->route('poll.show', ['slug' => $slug]);
            }
        }

        if ($post->media) {
            $media = Post::find($id)->getFirstMedia('posts');
        }

        if ($post->translations->count() >= 1) {

            if ($post->category->translations) {
                $category =  $post->category->translations->where('locale', App::getLocale())->first()->name;
            }

            $update = Carbon::createFromTimeStamp(strtotime($post->translations->first()->updated_at), config('app.timezone'))->isoFormat('LL');

        } else {
            // No translation in current locale - check for fallback translations
            return $this->handleNoTranslation($post, $id);
        }

        // Use guest layout for non-authenticated users, app layout for authenticated users
        $viewName = Auth::check() ? 'posts.show' : 'posts.show-guest';
        return ($post != null ? view($viewName, compact(['post','media','category','update'])) : abort(403));
    }

    /**
     * Handle case when no translation exists for current locale.
     * Check for available translations in other locales and offer fallback.
     */
    private function handleNoTranslation($post, $postId)
    {
        // Get all available translations for this post (active ones)
        $availableTranslation = PostTranslation::where('post_id', $postId)
            ->whereDate('from', '<=', now())
            ->where(function ($query) {
                $query->whereDate('till', '>', now())->orWhereNull('till');
            })
            ->first();

        $viewData = [
            'fallbackLocale' => null,
            'fallbackLanguageName' => null,
            'fallbackUrl' => null,
            'post' => $post,
        ];

        if ($availableTranslation) {
            // Found an available translation in another locale
            $fallbackLocale = $availableTranslation->locale;
            $fallbackLanguageName = Language::where('lang_code', $fallbackLocale)->first()->name ?? $fallbackLocale;

            // Generate URL to the same post in the fallback locale
            $fallbackUrl = \LaravelLocalization::getLocalizedURL($fallbackLocale, route('post.show', ['id' => $postId]));

            $viewData['fallbackLocale'] = $fallbackLocale;
            $viewData['fallbackLanguageName'] = __($fallbackLanguageName);
            $viewData['fallbackUrl'] = $fallbackUrl;
        }

        // Use guest layout for non-authenticated users, app layout for authenticated users
        $viewName = Auth::check() ? 'posts.no_translation' : 'posts.no_translation-guest';
        return view($viewName, $viewData);
    }

    /**
     * Show view by .../posts/{slug}.
     * Post will be shown in user's App:locale() language if available, even is the slug is in another language.
     *
     * @param  mixed $slug
     * @return void
     */
    public function showBySlug($slug)
    {
        $postTranslation = PostTranslation::where('slug', $slug)->get()->first();
        if (!$postTranslation) {
            return view('posts.not_found');
        }
        $id = $postTranslation->post_id;
        $locale = $postTranslation->locale;

        // Poll posts have their own page
        if (\App\Models\Poll::where('post_id', $id)->exists()) {
            return redirect()->route('poll.show', ['slug' => $slug]);
        }

        $post = Post::with([
            'postable' => function ($query) {
                $query->select(['id', 'name']);
            },
            'category' => function ($query) {
                $query->with('translations');
            },
            'meeting',
            'translations' => function ($query) {
                //TODO!: Currently only user 1 (Super-admin) can view unpublished posts, change to permission/role based!
                $query->where('locale', App::getLocale());
                // Only show published posts for guests and non-admin users
                if (!Auth::guard('web')->check() || Auth::guard('web')->user()->id != 1) {
                    $query->whereDate('from', '<=', now())
                        ->where(function ($query) {
                            $query->whereDate('till', '>', now())->orWhereNull('till');
                        });
                }
            }
        ])
        ->where('id', $id)
        ->first();


        if ($post->media) {
            $media = Post::find($id)->getFirstMedia('posts');
        }


        if ($post->translations->count() >= 1) {
            if ($post->category->translations) {
                $category =  $post->category->translations->where('locale', App::getLocale())->first()->name;
            }

            $update = Carbon::createFromTimeStamp(strtotime($post->translations->first()->updated_at), config('app.timezone'))->isoFormat('LL');

        } else {
            // No translation in current locale - check for fallback translations
            return $this->handleNoTranslation($post, $id);
        }

        // Use guest layout for non-authenticated users, app layout for authenticated users
        $viewName = Auth::check() ? 'posts.show' : 'posts.show-guest';
        return ($post != null ? view($viewName, compact(['post','media','category','update'])) : abort(403));

    }


    public function manage()
    {
        if (getActiveProfileType() !== 'Admin') {
            abort(403, __('Admin profile required'));
        }

        return view('posts.manage');
    }


    public function postPdf($id)
    {
        $data = $this->buildPostPdfData($id);
        $pdf = Pdf::loadView('posts.pdf', $data)
            ->setPaper('A4', 'portrait')
            ->setOptions([
                'isHtml5ParserEnabled' => true,
                'isRemoteEnabled'      => false,
                'defaultFont'          => 'DejaVu Sans',
                'dpi'                  => 150,
                'chroot'               => public_path(),
            ]);
        return $pdf->download('post-' . $data['post']->id . '.pdf');
    }

    public function postPdfBulk(\Illuminate\Http\Request $request)
    {
        $ids     = array_filter(array_map('intval', explode(',', $request->input('ids', ''))));
        $perPage = in_array((int) $request->input('per_page', 1), [1, 2, 4])
                    ? (int) $request->input('per_page', 1)
                    : 1;
        if (empty($ids)) abort(400);

        $activeProfileType = session('activeProfileType');
        $activeProfileId   = session('activeProfileId');
        $isAdmin = $activeProfileType === \App\Models\Admin::class
                || ($activeProfileType === \App\Models\Bank::class
                    && \App\Models\Bank::find($activeProfileId)?->level === 0);

        if (!$isAdmin) abort(403);

        $posts = [];
        foreach ($ids as $translationId) {
            $translation = PostTranslation::withTrashed()->find($translationId);
            if (!$translation) continue;

            $locale = $translation->locale ?? App::getLocale();
            $posts[] = $this->buildPostPdfDataForLocale($translation->post_id, $locale);
        }

        if (empty($posts)) abort(403);

        $view        = 'posts.pdf-bulk';
        $orientation = $perPage === 2 ? 'landscape' : 'portrait';

        $pdf = Pdf::loadView($view, compact('posts', 'perPage'))
            ->setPaper('A4', $orientation)
            ->setOptions([
                'isHtml5ParserEnabled' => true,
                'isRemoteEnabled'      => false,
                'defaultFont'          => 'DejaVu Sans',
                'dpi'                  => 150,
                'chroot'               => public_path(),
                'margin_top'           => 0,
                'margin_right'         => 0,
                'margin_bottom'        => 0,
                'margin_left'          => 0,
            ]);

        return $pdf->download('posts-bulk-' . now()->format('Ymd-His') . '.pdf');
    }

    private function buildPostPdfDataForLocale(int $postId, string $locale): array
    {
        $previous = App::getLocale();
        App::setLocale($locale);
        try {
            return $this->buildPostPdfData($postId);
        } finally {
            App::setLocale($previous);
        }
    }

    private function buildPostPdfData($id): array
    {
        $locale = App::getLocale();

        $post = Post::with([
            'author',
            'category.translations',
            'translations' => function ($query) use ($locale) {
                $query->where('locale', $locale);
            },
            'meeting.meetingable',
            'meeting.location.city.translations',
        ])->findOrFail($id);

        // Polls are for logged-in profiles only
        abort_if($post->isPoll() && !Auth::guard('web')->check(), 404);

        $translation = $post->translations->first();

        $categoryName = $post->category?->translations->firstWhere('locale', $locale)?->name
            ?? $post->category?->translations->first()?->name;

        $categoryType = $post->category?->type ?? '';
        $isEvent     = $categoryType === 'App\Models\Meeting';
        $isArticle   = $categoryType === 'App\Models\Article';
        $isNews      = $categoryType === 'App\Models\News';
        $isImagePost = str_starts_with($categoryType, 'App\Models\ImagePost');

        $update = $translation
            ? Carbon::parse($translation->updated_at)->isoFormat('LL')
            : null;

        // Hero image as base64 for DomPDF (GD for webp, direct read for others)
        $heroBase64 = null;
        $heroMedia  = $post->getFirstMedia('posts');
        if ($heroMedia) {
            $heroPath = $heroMedia->getPath();
            if (file_exists($heroPath)) {
                $raw = @file_get_contents($heroPath);
                if ($raw) {
                    $src = @imagecreatefromstring($raw);
                    if ($src) {
                        // Crop to A4 portrait aspect ratio (cover behaviour)
                        $srcW = imagesx($src);
                        $srcH = imagesy($src);
                        $dstW = 1240; // 210mm @ 150dpi
                        $dstH = 1754; // 297mm @ 150dpi
                        $scale = max($dstW / $srcW, $dstH / $srcH);
                        $scaledW = (int) round($srcW * $scale);
                        $scaledH = (int) round($srcH * $scale);
                        $cropX = (int) round(($scaledW - $dstW) / 2);
                        $cropY = (int) round(($scaledH - $dstH) / 2);
                        $dst = imagecreatetruecolor($dstW, $dstH);
                        imagecopyresampled($dst, $src, 0, 0, (int) round($cropX / $scale), (int) round($cropY / $scale), $dstW, $dstH, (int) round($dstW / $scale), (int) round($dstH / $scale));
                        // Boost saturation +50%: blend color image with its grayscale at factor > 1
                        // output = gray + (color - gray) * 1.5  →  clamp to 0-255
                        $gray = imagecreatetruecolor($dstW, $dstH);
                        imagecopy($gray, $dst, 0, 0, 0, 0, $dstW, $dstH);
                        imagefilter($gray, IMG_FILTER_GRAYSCALE);
                        for ($px = 0; $px < $dstW; $px++) {
                            for ($py = 0; $py < $dstH; $py++) {
                                $c = imagecolorat($dst, $px, $py);
                                $g = imagecolorat($gray, $px, $py);
                                $gr = ($g >> 16) & 0xFF;
                                $nr = max(0, min(255, (int) round($gr + ((($c >> 16) & 0xFF) - $gr) * 1.75)));
                                $ng = max(0, min(255, (int) round($gr + ((($c >> 8)  & 0xFF) - $gr) * 1.75)));
                                $nb = max(0, min(255, (int) round($gr + (($c        & 0xFF) - $gr) * 1.75)));
                                imagesetpixel($dst, $px, $py, ($nr << 16) | ($ng << 8) | $nb);
                            }
                        }
                        imagedestroy($gray);
                        ob_start();
                        imagejpeg($dst, null, 85);
                        $heroBase64 = 'data:image/jpeg;base64,' . base64_encode(ob_get_clean());
                        imagedestroy($src);
                        imagedestroy($dst);
                    }
                }
            }
        }

        // Author avatar as base64 (SVG skipped — GD cannot render SVG)
        $avatarBase64 = null;
        $author = $post->author;
        if ($author && $author->profile_photo_path) {
            $avatarPath = storage_path('app/public/' . $author->profile_photo_path);
            $ext = strtolower(pathinfo($avatarPath, PATHINFO_EXTENSION));
            if (file_exists($avatarPath) && $ext !== 'svg') {
                $mime = mime_content_type($avatarPath) ?: 'image/jpeg';
                $avatarBase64 = 'data:' . $mime . ';base64,' . base64_encode(file_get_contents($avatarPath));
            }
        }

        $brandColor = theme_color('brand') ?: '#000000';

        // Platform logo
        $logoBase64 = null;
        $logoPath = theme_email_logo_file();
        if (file_exists($logoPath)) {
            $logoBase64 = 'data:image/png;base64,' . base64_encode(file_get_contents($logoPath));
        }

        // Hero logo: invert RGB to white while preserving alpha transparency
        $logoWhiteBase64 = null;
        if ($logoPath && file_exists($logoPath)) {
            $src = @imagecreatefrompng($logoPath);
            if ($src) {
                $w = imagesx($src);
                $h = imagesy($src);
                $dst = imagecreatetruecolor($w, $h);
                imagealphablending($dst, false);
                imagesavealpha($dst, true);
                // Fill with transparent background
                $transparent = imagecolorallocatealpha($dst, 0, 0, 0, 127);
                imagefill($dst, 0, 0, $transparent);
                // Copy pixel by pixel, inverting RGB but keeping alpha
                for ($x = 0; $x < $w; $x++) {
                    for ($y = 0; $y < $h; $y++) {
                        $rgba  = imagecolorat($src, $x, $y);
                        $alpha = ($rgba >> 24) & 0x7F;
                        $r     = 255 - (($rgba >> 16) & 0xFF);
                        $g     = 255 - (($rgba >> 8) & 0xFF);
                        $b     = 255 - ($rgba & 0xFF);
                        imagesetpixel($dst, $x, $y, imagecolorallocatealpha($dst, $r, $g, $b, $alpha));
                    }
                }
                ob_start();
                imagepng($dst);
                $logoWhiteBase64 = 'data:image/png;base64,' . base64_encode(ob_get_clean());
                imagedestroy($src);
                imagedestroy($dst);
            }
        }

        // QR code as inline SVG (no ImageMagick needed)
        $postUrl = route('post.show', ['id' => $post->id]);
        $qrSvg = \SimpleSoftwareIO\QrCode\Facades\QrCode::format('svg')
            ->size(300)->margin(2)->errorCorrection('M')->color(0, 0, 0)->generate($postUrl);
        $qrBase64 = 'data:image/svg+xml;base64,' . base64_encode($qrSvg);

        // Sanitize and truncate content for PDF, preserving HTML formatting.
        // Truncation is based on plain-text length; the HTML is kept intact up to that point.
        $rawContent = $translation?->content ?? '';
        $plainContent = strip_tags($rawContent);
        $contentMax = 800;
        $isTruncated = mb_strlen($plainContent) > $contentMax;
        $pdfContent = \App\Helpers\StringHelper::sanitizeHtml($rawContent);

        // Pass the full excerpt — CSS overflow:hidden on .hero-excerpt clips it within the hero.
        $rawExcerpt = $translation?->excerpt ?? '';
        $pdfExcerpt = $rawExcerpt;

        $meetingCityName = null;
        if ($isEvent && $post->meeting?->location?->city) {
            $city = $post->meeting->location->city;
            $meetingCityName = $city->translations->firstWhere('locale', $locale)?->name
                ?? $city->translations->first()?->name;
        }

        return compact(
            'post', 'translation', 'categoryName', 'update',
            'categoryType', 'isEvent', 'isArticle', 'isNews', 'isImagePost',
            'heroBase64', 'avatarBase64', 'logoBase64', 'logoWhiteBase64', 'qrBase64',
            'pdfContent', 'isTruncated', 'pdfExcerpt', 'author', 'brandColor',
            'meetingCityName'
        );
    }

    public function notFound()
    {
        return view('posts.not_found');
    }
}