import * as comma from "add-commas";
import * as _ from "lodash";
import * as markdownTable from "markdown-table";
import * as yargs from "yargs";
import * as scanner from "../scanner";

export var command = "table";
export var describe = "Create a summary table of requested fields";

export function builder(yargs: yargs.Arguments)
{
    return yargs
        .help("help")

        .alias("f", "fields")
        .array("fields")
        .default("fields", ["_basename", "title"])

        .alias("t", "titles")
        .array("titles")

        .default("table-start", "| ")
        .default("table-end", " |")
        .default("table-delimiter", " | ")
        .boolean("table-rule")
        .default("table-rule", true)
        .boolean("table-header")
        .default("table-header", true)

        .default("list-delimiter", ", ")

        .alias("o", "output")
        .default("output", "-")

        .default("prefix", "")

        .demand(1);
}

export function handler(argv: any)
{
    var files = argv._.splice(1);
    var data = scanner.scanFiles(argv, files);
    render(argv, data);
}

export function render(argv, data)
{
    // Parse out the options and fields from the sources.
    var columns = parse(argv, argv.titles, argv.fields);

    // Create the header row.
    var header: any[] = [];

    for (var column1 of columns)
    {
        header.push(column1.header);
    }

    // Create the initial table with the header.
    var table = [header];

    // Loop through the results and get the fields we need to display.
    var totals: any = ["Totals"];

    for (var metadata of data)
    {
        // Add the row to the table.
        var row: any[] = [];
        table.push(row);

        // Loop through our fields and retrieve each one.
        for (var index = 0; index < columns.length; index++)
        {
            // Grab the value, even if nested.
            var column = columns[index];
            var value = _.get(metadata, column.ref);

            // If we have a list, format it with spaces.
            if (Array.isArray(value))
            {
                value = value.join(argv.listDelimiter);
            }

            // If we have totals, then add them.
            if (column.total)
            {
                totals[index] = totals[index] ? parseInt(totals[index]) : 0;
                totals[index] += parseInt(value);
            }

            // If we have commas requested, then add those.
            if (column.comma)
            {
                value = comma(value);
            }

            // Add the final row to the table.
            row.push(value);
        }
    }

    // If we have totals, then add it at the bottom.
    if (totals.length > 1)
    {
        for (var index2 = 0; index2 < columns.length && index2 < totals.length; index2++)
        {
            var column2 = columns[index2];

            if (column2.comma)
            {
                totals[index2] = comma(totals[index2]);
            }
        }

        table.push(totals);
    }

    // Format the results in a table.
    var formattedTable = markdownTable(table, {
        align: columns.map(c => c.align),
        delimiter: argv.tableDelimiter,
        start: argv.tableStart,
        end: argv.tableEnd,
        rule: argv.tableRule
    });

    // If we don't want the header row, strip off the first line.
    if (!argv.tableHeader)
    {
        formattedTable = formattedTable.substring(formattedTable.indexOf("\n") + 1);
    }

    console.log(formattedTable);
}

class Column
{
    ref: string;
    header: string;
    align: string = "l";
    comma: boolean = false;
    total: boolean = false;

    public set(field, header)
    {
        this.ref = this.parseSpecifier(field);
        this.header = this.parseSpecifier(header ? header : field);
    }

    private parseSpecifier(spec): string
    {
        // See if we have options.
        var m = spec.match(/^(.*?):([lcr.st]+)?$/);

        if (m)
        {
            // We have a match, so put the first part as the specifier.
            spec = m[1];

            for (var s of m[2])
            {
                switch (s)
                {
                    case "c":
                    case "l":
                    case "r":
                    case ".":
                        this.align = s;
                        break;

                    case "s":
                        this.comma = true;
                        break;

                    case "t":
                        this.total = true;
                        break;
                }
            }
        }

        // Return the resulting specifier.
        return spec;
    }
}

function parse(argv, titles, fields): Column[]
{
    var columns: Column[] = [];

    if (!titles) titles = [];

    for (var index = 0; index < fields.length; index++)
    {
        var column = new Column();

        column.set(
            fields[index],
            titles.length >= index ? titles[index] : undefined);

        columns.push(column);
    }

    return columns;
}

/* Notes

Comma-separated list of lists. I like spaces.
*/