/*
 * str: string
 *
 * Returns a string
 */
function escapeItem(str) {
    return str.replaceAll(/(\\*)\|/g, function(match, backslashes) {
        if (backslashes.length % 2 === 0) {
            backslashes += "\\";
        }
        return backslashes + "|";
    });
}

/*
 * escapedColumns: array of objects
 * escapedRow: array of string
 *
 * Returns a string
 */
function writeRow(escapedColumns, escapedRow) {
    let res = "";
    for (let i = 0; i < escapedColumns.length; i++) {
        let escapedColumn = escapedColumns[i];
        let escapedItem = escapedRow[i];
        res += `| ${escapedItem}${" ".repeat(escapedColumn.maxLength - escapedItem.length)} `;
    }
    res += "|";

    return res;
}

/*
 * escapedColumns: array of objects
 *
 * Returns a string
 */
function writeHeader(escapedColumns) {
    let headerRow = [];
    let delimiterRow = [];

    for (let escapedColumn of escapedColumns) {
        headerRow.push(escapedColumn.text);

        let delimiter = "";
        if (escapedColumn.leftAligned) {
            delimiter += ":";
        }
        delimiter += "-".repeat(escapedColumn.maxLength - escapedColumn.leftAligned - escapedColumn.rightAligned);
        if (escapedColumn.rightAligned) {
            delimiter += ":";
        }
        delimiterRow.push(delimiter);
    }

    return writeRow(escapedColumns, headerRow) + "\n" + writeRow(escapedColumns, delimiterRow);
}

/*
 * column: object
 * rows: array of array of strings
 * headerIndex: integer
 *
 * Returns an integer
 */
function calculateColumnLength(column, rows, columnIndex) {
    let length = Math.max(column.text.length, 3);

    for (let row of rows) {
        let item = row[columnIndex];
        if (item.length > length) {
            length = item.length;
        }
    }

    return length;
}

/*
 * table: object
 *
 * Returns a string
 */
function serializeTable(table) {
    let escapedColumns = [];
    let escapedRows = [];

    for (let column of table.columns) {
        escapedColumns.push({
            text: escapeItem(column.text),
            leftAligned: column.leftAligned,
            rightAligned: column.rightAligned
        });
    }

    for (let row of table.rows) {
        let escapedRow = [];
        for (let item of row) {
            escapedRow.push(escapeItem(item));
        }

        escapedRows.push(escapedRow);
    }

    for (let i = 0; i < escapedColumns.length; i++) {
        escapedColumns[i].maxLength = calculateColumnLength(escapedColumns[i], escapedRows, i);
    }

    let res = writeHeader(escapedColumns);
    for (let escapedRow of escapedRows) {
        res += "\n" + writeRow(escapedColumns, escapedRow);
    }
    return res;
}



// XXX: perhaps calculateColumnLength could be placed somewhere else?
export {serializeTable, calculateColumnLength};