SimenB/stylint

'use strict'

var fs = require( 'fs' )
var path = require( 'path' )
var userHome = require( 'user-home' )
var stripJsonComments = require( 'strip-json-comments' )
var Glob = require( 'glob' ).Glob

// @TODO i just this sloppy just to fix some stuff
// comes back and refactor / cleanup

/**
 * @description overrides default config with a new config object
 *              many potential code paths here.
 * 1: user passed in config object via function param
 * 2: user passes location of .stylintrc file to use via cli
 * 3: user has options obj in package.json or path to
 * 4: none of the above, fallback to initial config
 * 5: user has a .stylintrc file in a dir but doesnt pass anything
 * @param {String} [configpath] If defined, the path to a config-file to read
 * @returns {Function} kick off linter again
*/
var setConfig = function( configpath ) {
    var files = []
    var customPath = ''
    // return default config if nothing passed in or found
    var returnConfig
    var cwd = process.cwd()
    var pkg = null
    try {
        pkg = require( cwd + '/package.json' )
    }
    catch ( err ) {
        // no output
    }

    /**
     * @description sets the return config if one if found
     * @param  {string} path [where to look for config]
     * @return {Object|void} [object if stylintrc found, undefined if not]
     */
    var _parseConfig = function( path ) {
        return JSON.parse(
            stripJsonComments(
                fs.readFileSync( path, 'utf-8' )
            )
        )
    }

    /**
     * @description [reverse walk from cwd to usr]
     *              [if .stylintrc found, use it]
     * @param  {Array<string>} files [all files for this dir level]
     * @param  {number} level [# of dirs traversed so far]
     * @param  {string} cwd   [relative path to current directory being walked]
     * @return {?Object|?Function} [config if found, recurse if not. null if failed]
     */
    var _recurseDirectories = function( files, level, cwd ) {
        // parse stylintrc if found, stop recursion
        if ( files.indexOf( '.stylintrc' ) !== -1 ) {
            return _parseConfig( cwd + '/.stylintrc' )
        }

        // only go up to user home directory, stop recursion
        if ( userHome ) return null

        // next dir level
        var nextLevel = level + 1
        // pathArr is generated by applying our dir level
        // to cwd, and going backwards
        // ie, level = 1, pathArr = [ cwd, '..' ]
        // ie, level = 2, pathArr = [ cwd, '..', '..' ]
        // and so on
        var pathArr = [ cwd ]

        // push '..' for each dir level
        while ( level-- ) {
            pathArr.push( '..' )
        }

        // creates the path to the next directory
        var newPath = path.join.apply( null, pathArr )
        // gets the files for the next directory
        var newFiles = fs.readdirSync( newPath )
        // passes the newFiles, nextLevel, and newPath to itself
        // to start the process over again
        return _recurseDirectories( newFiles, nextLevel, newPath )
    }

    // if 1, the customConfig will be what we want
    // this only occurs if using stylint programmatically
    // ie, user passed in option object
    if ( this.customConfig ) {
        returnConfig = this.customConfig
    }
    // if 2, we pass in a path to the config
    // this only occurs if using stylint via the command line
    else if ( configpath ) {
        customPath = path.isAbsolute( configpath ) ? configpath : cwd + '/' + configpath
        try {
            returnConfig = _parseConfig( customPath )
        }
        catch ( err ) {
            throw err
        }
    }
    // 3, if user did not pass in option obj, or pass options via cli
    // check the user's package.json for either an option obj, or
    // at least a path to one
    else if ( pkg !== null &&
        typeof pkg.stylintrc !== 'undefined' ) {
        var rc = pkg.stylintrc

        if ( typeof rc === 'object' && !( rc instanceof Array ) ) {
            returnConfig = rc
        }
        else if ( typeof rc === 'string' ) {
            returnConfig = _parseConfig( rc )
        }
    }
    // 4, nothing passed in via cli or programmatically or via pkg
    // start at cwd, walk up to user home directory, if nothing
    // found, then just use the default config
    else {
        try {
            // recurse up to user home
            files = fs.readdirSync( cwd )
            // null if .stylintrc file found anywhere
            returnConfig = _recurseDirectories( files, 1, cwd )

            // default config if nothing found
            if ( !returnConfig ) {
                returnConfig = this.config
            }
        }
        // in case there's an issue parsing or no .stylintrc found at specified location
        catch ( err ) {
            throw err
        }
    }

    returnConfig.exclude = ( returnConfig.exclude || [] ).map( function( exclude ) {
        return new Glob( exclude, {
            matchBase: true
        } ).minimatch
    } )

    // make sure indentPref is set no matter what
    returnConfig.indentPref = returnConfig.indentPref || false

    // 5, just return the default config if nothing found
    return returnConfig
}

module.exports = setConfig