js/transforms.js - master - UzhvaD/Web_application_development_Course_work

js/transforms.js
127 строк5 KB
UzhvaD
create: style.css, app.js, database.js, scheduler.js, transforms.js, ui.js, utils.js
03 май 2026, 16:07
03 май 2026, 16:07b7726da
// ==================== ТРАНСФОРМАЦИИ ДАННЫХ ====================

function transformRemoveDuplicates(csvText) {
    const { headers, data, delimiter } = csvToObjects(csvText);
    if (!headers.length) return { csv: csvText, removed: 0, message: 'нет данных' };
    
    const seen = new Set();
    const unique = data.filter(row => {
        const key = headers.map(h => row[h]).join('|');
        if (seen.has(key)) return false;
        seen.add(key);
        return true;
    });
    
    const removed = data.length - unique.length;
    return {
        csv: objectsToCsv(headers, unique, delimiter),
        removed: removed,
        message: `удалено ${removed} дубликатов`
    };
}

function transformNormalizeNumbers(csvText) {
    const { headers, data, delimiter } = csvToObjects(csvText);
    if (!headers.length) return { csv: csvText, normalized: 0, message: 'нет данных' };
    
    const numericCols = headers.filter(col => {
        return data.some(row => {
            const val = parseFloat(row[col]);
            return !isNaN(val) && isFinite(val);
        });
    });
    
    if (numericCols.length === 0) {
        return { csv: csvText, normalized: 0, message: 'числовые колонки не найдены' };
    }
    
    const stats = {};
    numericCols.forEach(col => {
        const values = data.map(row => parseFloat(row[col])).filter(v => !isNaN(v));
        stats[col] = { min: Math.min(...values), max: Math.max(...values) };
    });
    
    const normalizedData = data.map(row => {
        const newRow = { ...row };
        numericCols.forEach(col => {
            const val = parseFloat(row[col]);
            if (!isNaN(val) && stats[col].max !== stats[col].min) {
                newRow[col] = ((val - stats[col].min) / (stats[col].max - stats[col].min)).toFixed(4);
            }
        });
        return newRow;
    });
    
    return {
        csv: objectsToCsv(headers, normalizedData, delimiter),  // ← ИСПРАВЛЕНО: normalizedData
        normalized: numericCols.length,
        message: `нормализовано ${numericCols.length} колонок`
    };
}

function transformUppercase(csvText) {
    const { headers, data, delimiter } = csvToObjects(csvText);
    if (!headers.length) return { csv: csvText, processed: 0, message: 'нет данных' };
    
    const processedData = data.map(row => {
        const newRow = { ...row };
        headers.forEach(col => {
            if (typeof row[col] === 'string') {
                newRow[col] = row[col].toUpperCase();
            } else if (row[col] !== undefined && row[col] !== null) {
                newRow[col] = String(row[col]).toUpperCase();
            }
        });
        return newRow;
    });
    
    return {
        csv: objectsToCsv(headers, processedData, delimiter),  // ← ИСПРАВЛЕНО: processedData
        processed: data.length,
        message: `обработано ${data.length} строк`
    };
}

function transformFillNA(csvText, fillValue = 'N/A') {
    const { headers, data, delimiter } = csvToObjects(csvText);
    if (!headers.length) return { csv: csvText, filled: 0, message: 'нет данных' };
    
    let filledCount = 0;
    const filledData = data.map(row => {
        const newRow = { ...row };
        headers.forEach(col => {
            if (row[col] === undefined || row[col] === null || row[col].trim() === '') {
                newRow[col] = fillValue;
                filledCount++;
            }
        });
        return newRow;
    });
    
    return {
        csv: objectsToCsv(headers, filledData, delimiter),
        filled: filledCount,
        message: `заполнено ${filledCount} пропусков`
    };
}

function applyTransform(transformType, csvText, options = {}) {
    switch (transformType) {
        case 'dedup':
            return transformRemoveDuplicates(csvText);
        case 'normalize':
            return transformNormalizeNumbers(csvText);
        case 'uppercase':
            return transformUppercase(csvText);
        case 'fillna':
            return transformFillNA(csvText, options.fillValue || 'N/A');
        default:
            return { csv: csvText, message: 'неизвестная трансформация' };
    }
}

window.applyTransform = applyTransform;
window.transformRemoveDuplicates = transformRemoveDuplicates;
window.transformNormalizeNumbers = transformNormalizeNumbers;
window.transformUppercase = transformUppercase;
window.transformFillNA = transformFillNA;