/* jslint node: true */
'use strict';

//	ENiGMA½
const Config	= require('./config.js').get;
const StatLog	= require('./stat_log.js');

//	deps
const _			= require('lodash');
const assert	= require('assert');

exports.parseAsset				= parseAsset;
exports.getAssetWithShorthand	= getAssetWithShorthand;
exports.getArtAsset				= getArtAsset;
exports.getModuleAsset			= getModuleAsset;
exports.resolveConfigAsset		= resolveConfigAsset;
exports.resolveSystemStatAsset	= resolveSystemStatAsset;
exports.getViewPropertyAsset	= getViewPropertyAsset;

const ALL_ASSETS = [
    'art',
    'menu',
    'method',
    'userModule',
    'systemMethod',
    'systemModule',
    'prompt',
    'config',
    'sysStat',
];

const ASSET_RE = new RegExp('\\@(' + ALL_ASSETS.join('|') + ')\\:([\\w\\d\\.]*)(?:\\/([\\w\\d\\_]+))*');

function parseAsset(s) {
    const m = ASSET_RE.exec(s);

    if(m) {
        let result = { type : m[1] };

        if(m[3]) {
            result.location = m[2];
            result.asset	= m[3];
        } else {
            result.asset	= m[2];
        }

        return result;
    }
}

function getAssetWithShorthand(spec, defaultType) {
    if(!_.isString(spec)) {
        return null;
    }

    if('@' === spec[0]) {
        const asset = parseAsset(spec);
        assert(_.isString(asset.type));

        return asset;
    }

    return {
        type	: defaultType,
        asset	: spec,
    };
}

function getArtAsset(spec) {
    const asset = getAssetWithShorthand(spec, 'art');

    if(!asset) {
        return null;
    }

    assert( ['art', 'method' ].indexOf(asset.type) > -1);
    return asset;
}

function getModuleAsset(spec) {
    const asset = getAssetWithShorthand(spec, 'systemModule');

    if(!asset) {
        return null;
    }

    assert( ['userModule', 'systemModule' ].includes(asset.type) );

    return asset;
}

function resolveConfigAsset(spec) {
    const asset = parseAsset(spec);
    if(asset) {
        assert('config' === asset.type);

        const path	= asset.asset.split('.');
        let conf	= Config();
        for(let i = 0; i < path.length; ++i) {
            if(_.isUndefined(conf[path[i]])) {
                return spec;
            }
            conf = conf[path[i]];
        }
        return conf;
    } else {
        return spec;
    }
}

function resolveSystemStatAsset(spec) {
    const asset = parseAsset(spec);
    if(!asset) {
        return spec;
    }

    assert('sysStat' === asset.type);

    return StatLog.getSystemStat(asset.asset) || spec;
}

function getViewPropertyAsset(src) {
    if(!_.isString(src) || '@' !== src.charAt(0)) {
        return null;
    }

    return parseAsset(src);
}