'use strict'; const os = require('os'); const hasFlag = require('has-flag');

const env = process.env;

let forceColor; if (hasFlag('no-color') ||

hasFlag('no-colors') ||
hasFlag('color=false')) {
forceColor = false;

} else if (hasFlag('color') ||

hasFlag('colors') ||
hasFlag('color=true') ||
hasFlag('color=always')) {
forceColor = true;

} if ('FORCE_COLOR' in env) {

forceColor = env.FORCE_COLOR.length === 0 || parseInt(env.FORCE_COLOR, 10) !== 0;

}

function translateLevel(level) {

if (level === 0) {
        return false;
}

return {
        level,
        hasBasic: true,
        has256: level >= 2,
        has16m: level >= 3
};

}

function supportsColor(stream) {

if (forceColor === false) {
        return 0;
}

if (hasFlag('color=16m') ||
        hasFlag('color=full') ||
        hasFlag('color=truecolor')) {
        return 3;
}

if (hasFlag('color=256')) {
        return 2;
}

if (stream && !stream.isTTY && forceColor !== true) {
        return 0;
}

const min = forceColor ? 1 : 0;

if (process.platform === 'win32') {
        // Node.js 7.5.0 is the first version of Node.js to include a patch to
        // libuv that enables 256 color output on Windows. Anything earlier and it
        // won't work. However, here we target Node.js 8 at minimum as it is an LTS
        // release, and Node.js 7 is not. Windows 10 build 10586 is the first Windows
        // release that supports 256 colors. Windows 10 build 14931 is the first release
        // that supports 16m/TrueColor.
        const osRelease = os.release().split('.');
        if (
                Number(process.versions.node.split('.')[0]) >= 8 &&
                Number(osRelease[0]) >= 10 &&
                Number(osRelease[2]) >= 10586
        ) {
                return Number(osRelease[2]) >= 14931 ? 3 : 2;
        }

        return 1;
}

if ('CI' in env) {
        if (['TRAVIS', 'CIRCLECI', 'APPVEYOR', 'GITLAB_CI'].some(sign => sign in env) || env.CI_NAME === 'codeship') {
                return 1;
        }

        return min;
}

if ('TEAMCITY_VERSION' in env) {
        return /^(9\.(0*[1-9]\d*)\.|\d{2,}\.)/.test(env.TEAMCITY_VERSION) ? 1 : 0;
}

if (env.COLORTERM === 'truecolor') {
        return 3;
}

if ('TERM_PROGRAM' in env) {
        const version = parseInt((env.TERM_PROGRAM_VERSION || '').split('.')[0], 10);

        switch (env.TERM_PROGRAM) {
                case 'iTerm.app':
                        return version >= 3 ? 3 : 2;
                case 'Apple_Terminal':
                        return 2;
                // No default
        }
}

if (/-256(color)?$/i.test(env.TERM)) {
        return 2;
}

if (/^screen|^xterm|^vt100|^vt220|^rxvt|color|ansi|cygwin|linux/i.test(env.TERM)) {
        return 1;
}

if ('COLORTERM' in env) {
        return 1;
}

if (env.TERM === 'dumb') {
        return min;
}

return min;

}

function getSupportLevel(stream) {

const level = supportsColor(stream);
return translateLevel(level);

}

module.exports = {

supportsColor: getSupportLevel,
stdout: getSupportLevel(process.stdout),
stderr: getSupportLevel(process.stderr)

};