<?php

namespace App\Ingest;

use Illuminate\Support\Facades\Storage;
use Symfony\Component\Process\Exception\ProcessFailedException;
use Symfony\Component\Process\Process;
use League\HTMLToMarkdown\HtmlConverter;

class Convertor
{
    /**
     * @var \Illuminate\Contracts\Filesystem\Filesystem
     */
    private $storage;
    private $path;
    protected $type;

    public function __construct($path, $type)
    {
        $this->storage = Storage::disk('local');
        $this->path = $path;
        $this->type = $type;
    }

    /**
     * @return mixed
     * @throws \Exception
     */
    public function execute()
    {
        if ($this->type === 'txt') {
            return $this->path;
        }

        if ($this->type === 'pdf') {
//            $this->convertPdfToText();
            $this->convertPdfToMD();
//            $this->getHtmlContentsFromPdfWithImages();

            return $this->path;
        }

        if ($this->type !== 'docx') {
            $this->convertToDocx();
        }

        $this->convertDocumentToText();
        //$this->convertToHtml();

        return $this->path;
    }

    /**
     * Convert doc,dot,rtf,odt,pdf,docx to docx
     *
     *
     * @return string|void
     */
    private function convertToDocx()
    {
        (new Process(['export HOME=' . env('USER_HOME_PATH')]))->run();

        /**
         * Convert doc,dot,rtf,odt to docx
         */
        $process = new Process([
            'soffice',
            '--headless',
            '--convert-to',
            'docx',
            $this->storage->path($this->path),
            '--outdir',
            $this->storage->path('contracts')
        ]);

        $process->run();

        if (!$process->isSuccessful()) {
            throw new ProcessFailedException($process);
        }

        $this->storage->delete($this->path);

        $this->path = str_replace(".$this->type", '.docx', $this->path);
    }

    /**
     * Convert docx file to text
     *
     * @return void
     */
    private function convertDocumentToText()
    {
        (new Process(['export HOME=' . env('USER_HOME_PATH')]))->run();

        $process = new Process([
            'soffice',
            '--headless',
            '--convert-to',
            'txt',
            $this->storage->path($this->path),
            '--outdir',
            $this->storage->path('contracts')
        ]);

        $process->run();

        if (!$process->isSuccessful()) {
            throw new ProcessFailedException($process);
        }

        $this->storage->delete($this->path);

        $this->path = str_replace(['.docx', '.bin'], '.txt', $this->path);
    }

    protected function convertPdfToText()
    {
        $this->prepareForConvertPDF();

        $images = $this->getImagesFromPDF();

        $contents = $this->getTextContentsFromPDF();

        if (!$contents && count($images) === 0) {
            throw new \Exception('Could not read from file.');
        }

        // Handle images and image contents.
        if (count($images) > 0) {
            foreach ($images as $image) {
                try {
                    $ocr = new OCR($this->storage->path($image));

                    $imageContents = $ocr->execute();

                    $contents = $contents . "\n" . $imageContents;
                } catch (\Exception $exception) {
                    \Illuminate\Support\Facades\Log::info('something wrong: ' . $exception->getMessage());
                }
            }

            $dir = str_replace('.pdf', '', $this->path);

            $this->storage->deleteDirectory($dir);
        }

        $this->storage->delete($this->path);

        $this->path = str_replace('.pdf', '.txt', $this->path);

        $this->storage->put($this->path, $contents);
    }

    protected function convertPdfToMD()
    {
//        $this->prepareForConvertPDF();

        $result = $this->getContentsFromPdf();

        if ( ! $result['has_images'] && ! $result['has_text']) {
            throw new \Exception('Cannot get pdf file contents.');
        }

        if ($result['has_text']) {
            if ($result['has_images']) {
                // Both text and images.
                throw new \Exception('Not supported for now.');
            }

            // Delete directory because the contents are in the '$result' variable.
            $this->storage->deleteDirectory($this->path);

            $mdContents = '';

            foreach ($result['htmls'] as $html) {
                $converter = new HtmlConverter();
                $converter->getConfig()->setOption('strip_tags', true);

                $contents = $converter->convert($html);

                $mdContents = $mdContents . $contents;
            }

            $this->path = "$this->path.md";

            $this->storage->put($this->path, $mdContents);

            return;
        }

        // Only contains images.
        $imagesContent = '';
        $files = $this->storage->allFiles($this->path);

        foreach ($files as $file) {
            // Only get the image files from the directory, it may contain some empty html files too.
            if (in_array(pathinfo($file, PATHINFO_EXTENSION), ['jpg', 'png'])) {
                $ocr = new OCR($this->storage->path($file));

                $imagesContent = $imagesContent . $ocr->execute();
            }
        }

        // We are done with the images processing, delete directory.
        $this->storage->deleteDirectory($this->path);

        $this->path = "$this->path.md";

        $this->storage->put($this->path, $imagesContent);
    }

    private function convertToHtml()
    {
        (new Process(['export HOME=' . env('USER_HOME_PATH')]))->run();

        $process = new Process([
            'soffice',
            '--headless',
            '--convert-to',
            'html:HTML:EmbedImages',
            $this->storage->path($this->path),
            '--outdir',
            $this->storage->path('contracts')
        ]);

        $process->run();

        if (!$process->isSuccessful()) {
            throw new ProcessFailedException($process);
        }

        $this->storage->delete($this->path);

        $this->path = str_replace(".$this->type", '.html', $this->path);
    }

    private function convertToXML()
    {
        //Convert the file to xml using pdftohtml to xml and run a python scrypt to fix the paragraphs
        $process = new Process([
            'pdftohtml',
            '-xml',
            '-i',
            $this->storage->path($this->path)
        ]);

        $process->run();

        if (!$process->isSuccessful()) {
            throw new ProcessFailedException($process);
        }

        $this->storage->delete($this->path);

        $this->path = str_replace(".$this->type", '.xml', $this->path);
    }

    protected function prepareForConvertPDF()
    {
        (new Process(['export HOME=' . env('USER_HOME_PATH')]))->run();

        $process = new Process([
            'pip3',
            'install',
            'pdftotext',
        ]);

        $process->run();

        if (!$process->isSuccessful()) {
            throw new ProcessFailedException($process);
        }
    }

    protected function getImagesFromPDF()
    {
        $dir = str_replace('.pdf', '', $this->path);

        $this->storage->makeDirectory($dir);

        $process = new Process([
            'pdfimages',
            '-p',
            $this->storage->path($this->path),
            '-tiff',
            $this->storage->path("$dir/ocr")
        ]);

        $process->run();

        if (!$process->isSuccessful()) {
            throw new ProcessFailedException($process);
        }

        return $this->storage->allFiles($dir);
    }

    protected function getTextContentsFromPDF()
    {
        $outputPath = $this->storage->path(str_replace('.pdf', '.txt', $this->path));

        $process = new Process([
            'python3',
            storage_path('scripts' . DIRECTORY_SEPARATOR . 'parse-pdf.py'),
            '-i',
            $this->storage->path($this->path),
            '-o',
            $outputPath
        ]);

        $process->run();

        if (!$process->isSuccessful()) {
            throw new ProcessFailedException($process);
        }

        return file_get_contents($outputPath);
    }

    protected function getHtmlContentsFromPdfWithImages()
    {
        $dirName = str_replace('.pdf', '', $this->path);
        $this->storage->makeDirectory($dirName);

        $outputPath = $this->storage->path("$dirName/html");

        $process = new Process([
            'pdftohtml',
            '-noframes',
            $this->storage->path($this->path),
            $outputPath
        ]);

        $process->run();

        if (!$process->isSuccessful()) {
            throw new ProcessFailedException($process);
        }

        $this->storage->delete($this->path);

        $this->path = $dirName;

        $converter = new HtmlConverter();
        $converter->getConfig()->setOption('strip_tags', true);

        $files = $this->storage->allFiles($this->path);

        $htmlFileIndex = null;

        foreach ($files as $index => $file) {
            // if (pathinfo($file, PATHINFO_BASENAME) === 'html-html.html') {
            // if (pathinfo($file, PATHINFO_EXTENSION) === 'html') {
            if (pathinfo($file, PATHINFO_BASENAME) === 'html.html') {
                $htmlFileIndex = $index;

                break;
            }
        }

        $htmlContents = $this->storage->get($files[$htmlFileIndex]);
        $contents = $converter->convert($htmlContents);

//        $this->storage->deleteDirectory($this->path);

        $this->path = "$this->path.md";

        $this->storage->put($this->path, $contents);

        dd(3);
    }

    protected function getContentsFromPdf()
    {
        $dirName = str_replace('.pdf', '', $this->path);
        $this->storage->makeDirectory($dirName);

        $outputPath = $this->storage->path("$dirName/html");

        $process = new Process([
            'pdftohtml',
            '-xml',
            $this->storage->path($this->path),
            $outputPath
        ]);

        $process->run();

        if (!$process->isSuccessful()) {
            throw new ProcessFailedException($process);
        }

        $this->storage->delete($this->path);

        $this->path = $dirName;

        $contents = $this->storage->get("$this->path/html.xml");

        $xml = simplexml_load_string($contents);

        $fonts = [];

        foreach ($xml->page as $page) {
            foreach ($page as $p) {
                if ($p->getName() === 'fontspec') {
                    $fonts[(int) $p['id']]['family'] = (string) $p['family'];
                    $fonts[(int) $p['id']]['size'] = (string) $p['size'];
                    $fonts[(int) $p['id']]['color'] = (string) $p['color'];
                }
            }
        }

        $htmls = [];
        $hasImages = false;
        $hasText = false;

        try {
            foreach ($xml->page as $page) {
                $html = '';

                $previousP = null;

                foreach ($page as $p) {
                    if ($p->getName() == 'image') {
                        $html = $html . '<img style="position: absolute; top: ' . $p['top'] . 'px; left: ' . $p['left'] . 'px;" width="' . $p['width'] . '" height="' . $p['height'] . '" src="' . $p['src'] . '">';

                        $hasImages = true;
                    }

                    if ($p->getName() == 'text') {
                        $id = (int) $p['font'];
                        $font_size = $fonts[$id]['size'];
                        $font_color = $fonts[$id]['color'];
                        $font_family = $fonts[$id]['family'];

                        $style = '';
                        $style = $style . 'position: absolute;';
                        $style = $style . "color: $font_color;";
                        $style = $style . "font-family: $font_family;";
                        $style = $style . "font-weight: 900;";
                        $style = $style . "width: " . $p['width'] . "px;";
                        $style = $style . "height: " . $p['height'] . "px;";
                        $style = $style . "top: " . $p['top'] . "px;";
                        $style = $style . "left: " . $p['left'] . "px;";

//                    $style = $style . "font-size: $font_size" . "px;";

                        if ($p->i) {
                            $content = '<i>' . $p->i . '</i>';
                        } else if ($p->b) {
                            $content = '<b>' . $p->b . '</b>';
                        } else {
                            $content = $p;
                        }

                        // @TODO Must chain paragraphs if top are almost same.

                        $tag = $this->getTag($p, $previousP, $font_size);

                        $html = $html . '<' . $tag . ' style="' . $style . '">' . $content . '</' . $tag . '>';

                        $hasText =  true;
                    }

                    $previousP = $p;
                }

                $htmls[] = '<html><head><title></title></head><body>' . $html . '</body></html>';
            }
        } catch (\Exception $exception) {
            \Illuminate\Support\Facades\Log::info($exception->getTraceAsString());
        }

        return [
            'has_images' => $hasImages,
            'has_text' => $hasText,
            'htmls' => $htmls,
        ];
    }

    protected function getTag($p, $previousP, $size)
    {
        if ($size > 24) {
            return 'h1';
        }

        if ($size > 18) {
            return 'h2';
        }

        if ($size > 16) {
            return 'h3';
        }

        if ($previousP && $p['top'] - $previousP['top'] <= 5) {
            return 'span';
        }

        return 'p';
    }
}