<?php

namespace NoccyLabs\Glabels;

use SimpleXMLElement;

class GlabelsLabel
{

    const XMLNS_GLABELS = "http://glabels.org/xmlns/3.0/";

    private $filename;

    /** @var SimpleXMLElement */
    private $root;

    public function __construct(?string $filename=null)
    {
        if ($filename) {
            $this->open($filename);
        }
    }

    public function open(string $filename)
    {
        $path = sprintf("compress.zlib://%s", realpath($filename));

        $xml = file_get_contents($path);

        $root = @simplexml_load_string($xml, "SimpleXMLElement", LIBXML_BIGLINES);
        if ($root) {
            $root->registerXPathNamespace("glabels", self::XMLNS_GLABELS);
            $this->root = $root;
        }

        $this->filename = $filename;
    }

    public function getFilename(): ?string
    {
        return $this->filename;
    }

    public function getMergeFields(): array
    {
        if (!$this->root) {
            throw GlabelsException::NoDocumentLoaded();
        }

        $fields = [];

        foreach ($this->root->xpath("//glabels:Field") as $field) {
            $fieldName = (string)$field['name'];
            if (!in_array($fieldName, $fields)) 
                $fields[] = $fieldName;
        }

        return $fields;
    }

    public function getTemplateInformation(): array
    {
        if (!$this->root) {
            throw GlabelsException::NoDocumentLoaded();
        }

        $template = $this->root->xpath("//glabels:Glabels-document/glabels:Template");
        $template = array_shift($template);

        $templateBrand = (string)$template['brand'];
        $templatePart = (string)$template['part'];
        $templateSize = [
            'width' => (string)$template['width'],
            'height' => (string)$template['height']
        ];
        $templateDescr = (string)$template['description'];

        $rotate = $this->root->xpath("//glabels:Objects");
        $rotate = array_shift($rotate);

        $rotate = ($rotate['rotate'] == "True");

        return [
            'brand' => $templateBrand,
            'part' => $templatePart,
            'description' => $templateDescr,
            'size' => $templateSize,
            'rotate' => $rotate
        ];
    }

    public function getMergeType(): string
    {
        if (!$this->root) {
            throw GlabelsException::NoDocumentLoaded();
        }

        $merge = $this->root->xpath("//glabels:Merge");
        $merge = array_shift($merge);

        return (string)$merge['type'];
    }

    public function generatePreview(string $output, array $data=null)
    {
        if (!$data) {
            $fields = $this->getMergeFields();
            $data = array_combine($fields, $fields);
        }

        $tempfile = sprintf("/tmp/%s.tmp", uniqid("php_glabels_"));
        $tempout = sprintf("/tmp/%s.pdf", uniqid("php_glabels_"));

        $fd = fopen($tempfile, "w");
        fputcsv($fd, array_keys($data));
        fputcsv($fd, array_values($data));
        fclose($fd);

        $mergeCmdline = sprintf(
            "glabels-3-batch -i %s -o %s %s", 
            escapeshellarg($tempfile),
            escapeshellarg($tempout),
            escapeshellarg($this->filename)
        );

        echo "\$ ".$mergeCmdline."\n";

        exec($mergeCmdline, $out, $ret);
        if ($ret != 0) {
            throw GlabelsException::MergeCommandFailed();
        }

        unlink($tempfile);

        $template = $this->getTemplateInformation();

        $args = [
            "-density 300",
            escapeshellarg($tempout)
        ];
        if ($template['rotate']) {
            $args[] = "-rotate 270";
        }
        $args[] = escapeshellarg($output);

        $convertCmdline = sprintf("convert %s", join(" ",$args));

        echo "\$ ".$convertCmdline."\n";

        exec($convertCmdline, $out, $ret);

        if ($ret != 0) {
            throw GlabelsException::ConvertCommandFailed();
        }

        unlink($tempout);

    }

}