// note: this is a work in progress
import { showLoader, hideLoader, showAlert } from '../ui.js';
import { downloadFile } from '../utils/helpers.js';
import html2canvas from 'html2canvas';


export async function mdToPdf() {
    // @ts-expect-error TS(2339) FIXME: Property 'jspdf' does not exist on type 'Window & ... Remove this comment to see the full error message
    if (typeof window.jspdf === 'undefined' || typeof window.html2canvas === 'undefined') {
        showAlert('Libraries Not Ready', 'PDF generation libraries are loading. Please try again.');
        return;
    }
    // @ts-expect-error TS(2339) FIXME: Property 'value' does not exist on type 'HTMLEleme... Remove this comment to see the full error message
    const markdownContent = document.getElementById('md-input').value.trim();
    if (!markdownContent) {
        showAlert('Input Required', 'Please enter some Markdown text.');
        return;
    }
    showLoader('Generating High-Quality PDF...');

    try {
        // @ts-expect-error TS(2304) FIXME: Cannot find name 'marked'.
        const htmlContent = marked.parse(markdownContent);
        // @ts-expect-error TS(2339) FIXME: Property 'value' does not exist on type 'HTMLEleme... Remove this comment to see the full error message
        const pageFormat = document.getElementById('page-format').value;
        // @ts-expect-error TS(2339) FIXME: Property 'value' does not exist on type 'HTMLEleme... Remove this comment to see the full error message
        const orientation = document.getElementById('orientation').value;
        // @ts-expect-error TS(2339) FIXME: Property 'value' does not exist on type 'HTMLEleme... Remove this comment to see the full error message
        const marginSize = document.getElementById('margin-size').value;

        const tempContainer = document.createElement('div');
        tempContainer.style.cssText = 'position: absolute; top: -9999px; left: -9999px; width: 800px; padding: 40px; background: white; color: black;';
        const styleSheet = document.createElement('style');
        styleSheet.textContent = `
            body { font-family: Helvetica, Arial, sans-serif; line-height: 1.6; font-size: 12px; }
            h1, h2, h3 { margin: 20px 0 10px 0; font-weight: 600; border-bottom: 1px solid #eaecef; padding-bottom: .3em; }
            h1 { font-size: 2em; } h2 { font-size: 1.5em; }
            p, blockquote, ul, ol, pre, table { margin: 0 0 16px 0; }
            blockquote { padding: 0 1em; color: #6a737d; border-left: .25em solid #dfe2e5; }
            pre { padding: 16px; overflow: auto; font-size: 85%; line-height: 1.45; background-color: #f6f8fa; border-radius: 6px; }
            code { font-family: 'Courier New', monospace; background-color: rgba(27,31,35,.05); border-radius: 3px; padding: .2em .4em; }
            table { width: 100%; border-collapse: collapse; } th, td { padding: 6px 13px; border: 1px solid #dfe2e5; }
            img { max-width: 100%; }
        `;
        tempContainer.appendChild(styleSheet);
        tempContainer.innerHTML += htmlContent;
        document.body.appendChild(tempContainer);

        const canvas = await html2canvas(tempContainer, { scale: 2, useCORS: true });
        document.body.removeChild(tempContainer);

        // @ts-expect-error TS(2339) FIXME: Property 'jspdf' does not exist on type 'Window & ... Remove this comment to see the full error message
        const { jsPDF } = window.jspdf;
        const pdf = new jsPDF({ orientation, unit: 'mm', format: pageFormat });
        const pageFormats = { 'a4': [210, 297], 'letter': [216, 279] };
        const format = pageFormats[pageFormat];
        const [pageWidth, pageHeight] = orientation === 'landscape' ? [format[1], format[0]] : format;
        const margins = { 'narrow': 10, 'normal': 20, 'wide': 30 };
        const margin = margins[marginSize];
        const contentWidth = pageWidth - (margin * 2);
        const contentHeight = pageHeight - (margin * 2);
        const imgData = canvas.toDataURL('image/png');
        const imgHeight = (canvas.height * contentWidth) / canvas.width;

        let heightLeft = imgHeight;
        let position = margin;
        pdf.addImage(imgData, 'PNG', margin, position, contentWidth, imgHeight);
        heightLeft -= contentHeight;

        while (heightLeft > 0) {
            position = position - pageHeight;
            pdf.addPage();
            pdf.addImage(imgData, 'PNG', margin, position, contentWidth, imgHeight);
            heightLeft -= contentHeight;
        }

        const pdfBlob = pdf.output('blob');
        downloadFile(pdfBlob, 'markdown-document.pdf');
    } catch (error) {
        console.error('MD to PDF conversion error:', error);
        showAlert('Conversion Error', 'Failed to generate PDF.');
    } finally {
        hideLoader();
    }
}