const path = require("path"),
chokidar = require("chokidar"),
fs = require("fs")

var paths = {
    static: path.join(__dirname, "static"),
    postUrl: path.join(__dirname, "resources/html/postUrl.html"),
    redirWarn: path.join(__dirname, "resources/html/redirWarn.html"),
    data: path.join(__dirname, "data"),
    config: path.join(__dirname, "data/config.json"),
    defaultConfig: path.join(__dirname, "resources/json/config.json"),
    urls: path.join(__dirname, "data/urls.json")
}

if (!fs.existsSync(paths.data)) {
    fs.mkdirSync(paths.data)
}

module.exports = {
    paths,
    config: undefined,
    urls: [],
    writeUrls: function (props) {
        var urls = module.exports.urls
        props.shortCode = 0
        
        for (var i in urls) {
            props.shortCode = urls[i].shortCode + 1
        }

        if (props.shortCode > 100000) {
            props.shortCode = 0
        }

        urls.push(props)

        var expirePoint = 0

        for (var i in urls) {
            var url = urls[i] 
            if (url.expire < Date.now()) {
                expirePoint = i
                continue
            }
        }

        urls.splice(0, expirePoint)

        fs.writeFileSync(paths.urls, JSON.stringify(module.exports.urls))
        return props
    }
}

if (!fs.existsSync(paths.config)) {
    fs.writeFileSync(paths.config, "{}")
}

var currentConfig = JSON.parse(fs.readFileSync(paths.config))
var defaultConfig = JSON.parse(fs.readFileSync(paths.defaultConfig))
currentConfig = Object.assign({}, defaultConfig, currentConfig)
fs.writeFileSync(paths.config, JSON.stringify(currentConfig))

var watcher = chokidar.watch(paths.data)

function dataUpdate() {
    module.exports.config = JSON.parse(fs.readFileSync(paths.config))
}

watcher
.on("change", dataUpdate)
.on("add", dataUpdate)

if (!fs.existsSync(paths.urls)) {
    fs.writeFileSync(paths.urls, "[]")
}

module.exports.urls = JSON.parse(fs.readFileSync(paths.urls))