/**

* Module dependencies.
*/

const tty = require('tty'); const util = require('util');

/**

* This is the Node.js implementation of `debug()`.
*/

exports.init = init; exports.log = log; exports.formatArgs = formatArgs; exports.save = save; exports.load = load; exports.useColors = useColors;

/**

* Colors.
*/

exports.colors = [6, 2, 3, 4, 5, 1];

try {

// Optional dependency (as in, doesn't need to be installed, NOT like optionalDependencies in package.json)
// eslint-disable-next-line import/no-extraneous-dependencies
const supportsColor = require('supports-color');

if (supportsColor && (supportsColor.stderr || supportsColor).level >= 2) {
        exports.colors = [
                20,
                21,
                26,
                27,
                32,
                33,
                38,
                39,
                40,
                41,
                42,
                43,
                44,
                45,
                56,
                57,
                62,
                63,
                68,
                69,
                74,
                75,
                76,
                77,
                78,
                79,
                80,
                81,
                92,
                93,
                98,
                99,
                112,
                113,
                128,
                129,
                134,
                135,
                148,
                149,
                160,
                161,
                162,
                163,
                164,
                165,
                166,
                167,
                168,
                169,
                170,
                171,
                172,
                173,
                178,
                179,
                184,
                185,
                196,
                197,
                198,
                199,
                200,
                201,
                202,
                203,
                204,
                205,
                206,
                207,
                208,
                209,
                214,
                215,
                220,
                221
        ];
}

} catch (error) {

// Swallow - we only care if `supports-color` is available; it doesn't have to be.

}

/**

* Build up the default `inspectOpts` object from the environment variables.
*
*   $ DEBUG_COLORS=no DEBUG_DEPTH=10 DEBUG_SHOW_HIDDEN=enabled node script.js
*/

exports.inspectOpts = Object.keys(process.env).filter(key => {

return /^debug_/i.test(key);

}).reduce((obj, key) => {

// Camel-case
const prop = key
        .substring(6)
        .toLowerCase()
        .replace(/_([a-z])/g, (_, k) => {
                return k.toUpperCase();
        });

// Coerce string value into JS value
let val = process.env[key];
if (/^(yes|on|true|enabled)$/i.test(val)) {
        val = true;
} else if (/^(no|off|false|disabled)$/i.test(val)) {
        val = false;
} else if (val === 'null') {
        val = null;
} else {
        val = Number(val);
}

obj[prop] = val;
return obj;

}, {});

/**

* Is stdout a TTY? Colored output is enabled when `true`.
*/

function useColors() {

return 'colors' in exports.inspectOpts ?
        Boolean(exports.inspectOpts.colors) :
        tty.isatty(process.stderr.fd);

}

/**

* Adds ANSI color escape codes if enabled.
*
* @api public
*/

function formatArgs(args) {

const {namespace: name, useColors} = this;

if (useColors) {
        const c = this.color;
        const colorCode = '\u001B[3' + (c < 8 ? c : '8;5;' + c);
        const prefix = `  ${colorCode};1m${name} \u001B[0m`;

        args[0] = prefix + args[0].split('\n').join('\n' + prefix);
        args.push(colorCode + 'm+' + module.exports.humanize(this.diff) + '\u001B[0m');
} else {
        args[0] = getDate() + name + ' ' + args[0];
}

}

function getDate() {

if (exports.inspectOpts.hideDate) {
        return '';
}
return new Date().toISOString() + ' ';

}

/**

* Invokes `util.format()` with the specified arguments and writes to stderr.
*/

function log(…args) {

return process.stderr.write(util.format(...args) + '\n');

}

/**

* Save `namespaces`.
*
* @param {String} namespaces
* @api private
*/

function save(namespaces) {

if (namespaces) {
        process.env.DEBUG = namespaces;
} else {
        // If you set a process.env field to null or undefined, it gets cast to the
        // string 'null' or 'undefined'. Just delete instead.
        delete process.env.DEBUG;
}

}

/**

* Load `namespaces`.
*
* @return {String} returns the previously persisted debug modes
* @api private
*/

function load() {

return process.env.DEBUG;

}

/**

* Init logic for `debug` instances.
*
* Create a new `inspectOpts` object in case `useColors` is set
* differently for a particular `debug` instance.
*/

function init(debug) {

debug.inspectOpts = {};

const keys = Object.keys(exports.inspectOpts);
for (let i = 0; i < keys.length; i++) {
        debug.inspectOpts[keys[i]] = exports.inspectOpts[keys[i]];
}

}

module.exports = require('./common')(exports);

const {formatters} = module.exports;

/**

* Map %o to `util.inspect()`, all on a single line.
*/

formatters.o = function (v) {

this.inspectOpts.colors = this.useColors;
return util.inspect(v, this.inspectOpts)
        .replace(/\s*\n\s*/g, ' ');

};

/**

* Map %O to `util.inspect()`, allowing multiple lines if needed.
*/

formatters.O = function (v) {

this.inspectOpts.colors = this.useColors;
return util.inspect(v, this.inspectOpts);

};