bentopdf/src/js/utils/helpers.ts

const STANDARD_SIZES = {
    'A4': { width: 595.28, height: 841.89 },
    'Letter': { width: 612, height: 792 },
    'Legal': { width: 612, height: 1008 },
    'Tabloid': { width: 792, height: 1224 },
    'A3': { width: 841.89, height: 1190.55 },
    'A5': { width: 419.53, height: 595.28 },
};

export function getStandardPageName(width: any, height: any) {
    const tolerance = 1; // Allow for minor floating point variations
    for (const [name, size] of Object.entries(STANDARD_SIZES)) {
        if ((Math.abs(width - size.width) < tolerance && Math.abs(height - size.height) < tolerance) ||
            (Math.abs(width - size.height) < tolerance && Math.abs(height - size.width) < tolerance)) {
            return name;
        }
    }
    return 'Custom';
}

export function convertPoints(points: any, unit: any) {
    let result = 0;
    switch (unit) {
        case 'in':
            result = points / 72;
            break;
        case 'mm':
            result = (points / 72) * 25.4;
            break;
        case 'px':
            result = points * (96 / 72); // Assuming 96 DPI
            break;
        default: // 'pt'
            result = points;
            break;
    }
    return result.toFixed(2);
}

export const hexToRgb = (hex: any) => {
    const result = /^#?([a-f\d]{2})([a-f\d]{2})([a-f\d]{2})$/i.exec(hex);
    return result ? {
        r: parseInt(result[1], 16) / 255,
        g: parseInt(result[2], 16) / 255,
        b: parseInt(result[3], 16) / 255,
    } : { r: 0, g: 0, b: 0 }; // Default to black
};

export const formatBytes = (bytes: any, decimals = 1) => {
    if (bytes === 0) return '0 Bytes';
    const k = 1024;
    const dm = decimals < 0 ? 0 : decimals;
    const sizes = ['Bytes', 'KB', 'MB', 'GB', 'TB'];
    const i = Math.floor(Math.log(bytes) / Math.log(k));
    return parseFloat((bytes / Math.pow(k, i)).toFixed(dm)) + ' ' + sizes[i];
};

export const downloadFile = (blob: any, filename: any) => {
    const url = URL.createObjectURL(blob);
    const a = document.createElement('a');
    a.href = url;
    a.download = filename;
    document.body.appendChild(a);
    a.click();
    document.body.removeChild(a);
    URL.revokeObjectURL(url);
};

export const readFileAsArrayBuffer = (file: any) => {
    return new Promise((resolve, reject) => {
        const reader = new FileReader();
        reader.onload = () => resolve(reader.result);
        reader.onerror = (error) => reject(error);
        reader.readAsArrayBuffer(file);
    });
};

export function parsePageRanges(rangeString: any, totalPages: any) {
    if (!rangeString || rangeString.trim() === '') {
        return Array.from({ length: totalPages }, (_, i) => i);
    }

    const indices = new Set();
    const parts = rangeString.split(',');

    for (const part of parts) {
        const trimmedPart = part.trim();
        if (!trimmedPart) continue;

        if (trimmedPart.includes('-')) {
            const [start, end] = trimmedPart.split('-').map(Number);
            if (isNaN(start) || isNaN(end) || start < 1 || end > totalPages || start > end) {
                console.warn(`Invalid range skipped: ${trimmedPart}`);
                continue;
            }

            for (let i = start; i <= end; i++) {
                indices.add(i - 1); 
            }
        } else {
            const pageNum = Number(trimmedPart);
            
            if (isNaN(pageNum) || pageNum < 1 || pageNum > totalPages) {
                console.warn(`Invalid page number skipped: ${trimmedPart}`);
                continue;
            }
            indices.add(pageNum - 1); 
        }
    }

    // @ts-expect-error TS(2362) FIXME: The left-hand side of an arithmetic operation must... Remove this comment to see the full error message
    return Array.from(indices).sort((a, b) => a - b);
}