/**

* 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;

exports.destroy = util.deprecate(

() => {},

'Instance method `debug.destroy()` is deprecated and no longer does anything. It will be removed in the next major version of `debug`.'

);

/**

* 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)

.split('\n')

.map(str => str.trim())

.join(' ');

};

/**

* 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);

};