'use strict';
const escapeStringRegexp = require('escape-string-regexp');
const ansiStyles = require('ansi-styles');
const stdoutColor = require('supports-color').stdout;

const template = require('./templates.js');

const isSimpleWindowsTerm = process.platform === 'win32' && !(process.env.TERM || '').toLowerCase().startsWith('xterm');

// `supportsColor.level` → `ansiStyles.color[name]` mapping
const levelMapping = ['ansi', 'ansi', 'ansi256', 'ansi16m'];

// `color-convert` models to exclude from the Chalk API due to conflicts and such
const skipModels = new Set(['gray']);

const styles = Object.create(null);

function applyOptions(obj, options) {
    options = options || {};

    // Detect level if not set manually
    const scLevel = stdoutColor ? stdoutColor.level : 0;
    obj.level = options.level === undefined ? scLevel : options.level;
    obj.enabled = 'enabled' in options ? options.enabled : obj.level > 0;
}

function Chalk(options) {
    // We check for this.template here since calling `chalk.constructor()`
    // by itself will have a `this` of a previously constructed chalk object
    if (!this || !(this instanceof Chalk) || this.template) {
        const chalk = {};
        applyOptions(chalk, options);

        chalk.template = function () {
            const args = [].slice.call(arguments);
            return chalkTag.apply(null, [chalk.template].concat(args));
        };

        Object.setPrototypeOf(chalk, Chalk.prototype);
        Object.setPrototypeOf(chalk.template, chalk);

        chalk.template.constructor = Chalk;

        return chalk.template;
    }

    applyOptions(this, options);
}

// Use bright blue on Windows as the normal blue color is illegible
if (isSimpleWindowsTerm) {
    ansiStyles.blue.open = '\u001B[94m';
}

for (const key of Object.keys(ansiStyles)) {
    ansiStyles[key].closeRe = new RegExp(escapeStringRegexp(ansiStyles[key].close), 'g');

    styles[key] = {
        get() {
            const codes = ansiStyles[key];
            return build.call(this, this._styles ? this._styles.concat(codes) : [codes], this._empty, key);
        }
    };
}

styles.visible = {
    get() {
        return build.call(this, this._styles || [], true, 'visible');
    }
};

ansiStyles.color.closeRe = new RegExp(escapeStringRegexp(ansiStyles.color.close), 'g');
for (const model of Object.keys(ansiStyles.color.ansi)) {
    if (skipModels.has(model)) {
        continue;
    }

    styles[model] = {
        get() {
            const level = this.level;
            return function () {
                const open = ansiStyles.color[levelMapping[level]][model].apply(null, arguments);
                const codes = {
                    open,
                    close: ansiStyles.color.close,
                    closeRe: ansiStyles.color.closeRe
                };
                return build.call(this, this._styles ? this._styles.concat(codes) : [codes], this._empty, model);
            };
        }
    };
}

ansiStyles.bgColor.closeRe = new RegExp(escapeStringRegexp(ansiStyles.bgColor.close), 'g');
for (const model of Object.keys(ansiStyles.bgColor.ansi)) {
    if (skipModels.has(model)) {
        continue;
    }

    const bgModel = 'bg' + model[0].toUpperCase() + model.slice(1);
    styles[bgModel] = {
        get() {
            const level = this.level;
            return function () {
                const open = ansiStyles.bgColor[levelMapping[level]][model].apply(null, arguments);
                const codes = {
                    open,
                    close: ansiStyles.bgColor.close,
                    closeRe: ansiStyles.bgColor.closeRe
                };
                return build.call(this, this._styles ? this._styles.concat(codes) : [codes], this._empty, model);
            };
        }
    };
}

const proto = Object.defineProperties(() => {}, styles);

function build(_styles, _empty, key) {
    const builder = function () {
        return applyStyle.apply(builder, arguments);
    };

    builder._styles = _styles;
    builder._empty = _empty;

    const self = this;

    Object.defineProperty(builder, 'level', {
        enumerable: true,
        get() {
            return self.level;
        },
        set(level) {
            self.level = level;
        }
    });

    Object.defineProperty(builder, 'enabled', {
        enumerable: true,
        get() {
            return self.enabled;
        },
        set(enabled) {
            self.enabled = enabled;
        }
    });

    // See below for fix regarding invisible grey/dim combination on Windows
    builder.hasGrey = this.hasGrey || key === 'gray' || key === 'grey';

    // `__proto__` is used because we must return a function, but there is
    // no way to create a function with a different prototype
    builder.__proto__ = proto; // eslint-disable-line no-proto

    return builder;
}

function applyStyle() {
    // Support varags, but simply cast to string in case there's only one arg
    const args = arguments;
    const argsLen = args.length;
    let str = String(arguments[0]);

    if (argsLen === 0) {
        return '';
    }

    if (argsLen > 1) {
        // Don't slice `arguments`, it prevents V8 optimizations
        for (let a = 1; a < argsLen; a++) {
            str += ' ' + args[a];
        }
    }

    if (!this.enabled || this.level <= 0 || !str) {
        return this._empty ? '' : str;
    }

    // Turns out that on Windows dimmed gray text becomes invisible in cmd.exe,
    // see https://github.com/chalk/chalk/issues/58
    // If we're on Windows and we're dealing with a gray color, temporarily make 'dim' a noop.
    const originalDim = ansiStyles.dim.open;
    if (isSimpleWindowsTerm && this.hasGrey) {
        ansiStyles.dim.open = '';
    }

    for (const code of this._styles.slice().reverse()) {
        // Replace any instances already present with a re-opening code
        // otherwise only the part of the string until said closing code
        // will be colored, and the rest will simply be 'plain'.
        str = code.open + str.replace(code.closeRe, code.open) + code.close;

        // Close the styling before a linebreak and reopen
        // after next line to fix a bleed issue on macOS
        // https://github.com/chalk/chalk/pull/92
        str = str.replace(/\r?\n/g, `${code.close}$&${code.open}`);
    }

    // Reset the original `dim` if we changed it to work around the Windows dimmed gray issue
    ansiStyles.dim.open = originalDim;

    return str;
}

function chalkTag(chalk, strings) {
    if (!Array.isArray(strings)) {
        // If chalk() was called by itself or with a string,
        // return the string itself as a string.
        return [].slice.call(arguments, 1).join(' ');
    }

    const args = [].slice.call(arguments, 2);
    const parts = [strings.raw[0]];

    for (let i = 1; i < strings.length; i++) {
        parts.push(String(args[i - 1]).replace(/[{}\\]/g, '\\$&'));
        parts.push(String(strings.raw[i]));
    }

    return template(chalk, parts.join(''));
}

Object.defineProperties(Chalk.prototype, styles);

module.exports = Chalk(); // eslint-disable-line new-cap
module.exports.supportsColor = stdoutColor;
module.exports.default = module.exports; // For TypeScript