/**
 * Storage Saturation Report - Main JavaScript
 * Loads report via mode=getreport. PDF/Image export via client-side jsPDF + html2canvas (no XI Chromium pipeline).
 */

$(document).ready(function() {
    load_report();

    $('#export-pdf-btn').on('click', function() {
        exportToPdf();
    });

    $('#export-image-btn').on('click', function() {
        exportToImage();
    });

    function load_report() {
        var baseUrl = window.saturationreportBaseUrl || (window.location.pathname.replace(/\/[^/]*$/, '/index.php'));
        var url = baseUrl + '?mode=getreport';

        $.get(url, function(html) {
            $('#report').html(html);
        }).fail(function() {
            $('#report').html(
                '<div class="alert alert-danger">' +
                'Error loading storage saturation report.' +
                '</div>'
            );
        });
    }

    function getComponentBase() {
        return (window.saturationreportBaseUrl || '').replace(/\/[^/]*$/, '');
    }

    function loadScript(src, onload, onerror) {
        var script = document.createElement('script');
        script.src = src;
        script.onload = onload;
        script.onerror = onerror || function() {};
        document.head.appendChild(script);
    }

    function exportToPdf() {
        var btn = $('#export-pdf-btn');
        var originalText = btn.html();
        btn.prop('disabled', true).html('<i class="fa fa-spinner fa-spin"></i> Generating...');

        function doPdf() {
            if (typeof html2canvas === 'undefined') {
                var componentBase = getComponentBase();
                var localH2c = componentBase ? (componentBase + '/scripts/vendor/html2canvas.min.js') : '';
                var cdnH2c = 'https://cdnjs.cloudflare.com/ajax/libs/html2canvas/1.4.1/html2canvas.min.js';
                loadScript(localH2c || cdnH2c, function() { doPdf(); }, function() {
                    if (localH2c) { loadScript(cdnH2c, doPdf, fallbackPdf); return; }
                    fallbackPdf();
                });
                return;
            }
            if (typeof window.jspdf === 'undefined' || !window.jspdf.jsPDF) {
                var componentBase = getComponentBase();
                var localJspdf = componentBase ? (componentBase + '/scripts/vendor/jspdf.umd.min.js') : '';
                var cdnJspdf = 'https://cdnjs.cloudflare.com/ajax/libs/jspdf/2.5.1/jspdf.umd.min.js';
                loadScript(localJspdf || cdnJspdf, doPdf, function() {
                    if (localJspdf) loadScript(cdnJspdf, doPdf, fallbackPdf);
                    else fallbackPdf();
                });
                return;
            }
            var container = document.getElementById('saturationreport-container');
            if (!container) container = document.getElementById('report');
            if (!container) {
                alert('Report container not found');
                btn.prop('disabled', false).html(originalText);
                return;
            }
            html2canvas(container, {
                backgroundColor: '#ffffff',
                scale: 2,
                logging: false,
                useCORS: true
            }).then(function(canvas) {
                try {
                    var JsPDF = window.jspdf.jsPDF;
                    var doc = new JsPDF('p', 'mm', 'a4');
                    var pageW = doc.internal.pageSize.getWidth();
                    var pageH = doc.internal.pageSize.getHeight();
                    var margin = 10;
                    var maxW = pageW - 2 * margin;
                    var maxH = pageH - 2 * margin;
                    var imgW = maxW;
                    var imgH = (canvas.height * maxW) / canvas.width;
                    if (imgH > maxH) {
                        imgH = maxH;
                        imgW = (canvas.width * maxH) / canvas.height;
                    }
                    doc.addImage(canvas.toDataURL('image/png'), 'PNG', margin, margin, imgW, imgH);
                    doc.save('storage-saturation-report-' + new Date().getTime() + '.pdf');
                } catch (err) {
                    console.error('PDF export error:', err);
                    alert('Failed to generate PDF. Try Print to PDF from the browser.');
                }
                btn.prop('disabled', false).html(originalText);
            }).catch(function(err) {
                console.error('Capture error:', err);
                fallbackPdf();
            });
        }

        function fallbackPdf() {
            btn.prop('disabled', false).html(originalText);
            window.print();
        }

        doPdf();
    }

    function exportToImage() {
        if (typeof html2canvas === 'undefined') {
            var componentBase = (window.saturationreportBaseUrl || '').replace(/\/[^/]*$/, '');
            var localSrc = componentBase ? (componentBase + '/scripts/vendor/html2canvas.min.js') : '';
            var cdnSrc = 'https://cdnjs.cloudflare.com/ajax/libs/html2canvas/1.4.1/html2canvas.min.js';
            var script = document.createElement('script');
            script.src = localSrc || cdnSrc;
            script.onload = function() { captureImage(); };
            script.onerror = function() {
                if (localSrc && script.src === localSrc) {
                    var fallback = document.createElement('script');
                    fallback.src = cdnSrc;
                    fallback.onload = function() { captureImage(); };
                    fallback.onerror = function() {
                        alert('Failed to load image export library. Please try using browser screenshot or print-to-PDF instead.');
                    };
                    document.head.appendChild(fallback);
                } else {
                    alert('Failed to load image export library. Please try using browser screenshot or print-to-PDF instead.');
                }
            };
            document.head.appendChild(script);
        } else {
            captureImage();
        }
    }

    function captureImage() {
        var container = document.getElementById('saturationreport-container');
        if (!container) {
            container = document.getElementById('report');
        }
        if (!container) {
            alert('Report container not found');
            return;
        }

        var btn = $('#export-image-btn');
        var originalText = btn.html();
        btn.prop('disabled', true).html('<i class="fa fa-spinner fa-spin"></i> Generating...');

        html2canvas(container, {
            backgroundColor: '#ffffff',
            scale: 2,
            logging: false,
            useCORS: true
        }).then(function(canvas) {
            var link = document.createElement('a');
            link.download = 'saturation-report-' + new Date().getTime() + '.png';
            link.href = canvas.toDataURL('image/png');
            link.click();
            btn.prop('disabled', false).html(originalText);
        }).catch(function(err) {
            console.error('Error capturing image:', err);
            alert('Failed to generate image. Please try using browser screenshot or print-to-PDF instead.');
            btn.prop('disabled', false).html(originalText);
        });
    }
});