nintendo_store_watcher.gs

var Discord = (function(){
    var w = function(id, token){
        this.id = id;
        this.token = token;
    };
    w.prototype = {
        _endpoint: function(){
            return 'https://discordapp.com/api/webhooks/' + this.id + '/' + this.token;
        },
        send: function(content){
            UrlFetchApp.fetch(this._endpoint(), { 'method': 'post', 'payload': { 'content': content } });
        }
    };
    return w;
})();

var SpreadSheet = (function () { // 完成した内部クラスの提供
    var c = function (sid, sname) {
        this.inner = SpreadsheetApp.openById(sid).getSheetByName(sname);
    };
    c.prototype = {
        addRows: function (rows) {
            var height = rows.length;
            if (height <= 0)return;
            var width = rows[0].length;
            if (width <= 0)return;
            var headRow = this.inner.getLastRow() + 1;
            Logger.log([headRow, 1, headRow + height - 1, width]);
            this.inner.getRange(headRow, 1, height, width).setValues(rows);
        },
        addRow: function (row) {
            this.addRows([row]);
        },
        setRow: function (row, toRow) {
            var width = row.length;
            if (width <= 0)return;
            this.inner.getRange(toRow, 1, 1, width).setValues([row]);
        },
        addCell: function (cell) {
            this.addRows([[cell]]);
        },
        getDataFromRow: function (targetRow) {
            return this.inner.getRange(targetRow, 1, 1, this.inner.getLastColumn()).getDisplayValues()[0];
        },
        getAllRows: function () {
            return this.inner.getRange(1, 1, this.inner.getLastRow(), this.inner.getLastColumn()).getDisplayValues();
        }
    };
    return c;
})();


var KVS = (function () {
    var e = function (k, v, r, s) {
        this.r = r;
        this.k = k;
        this.v = v;
        this.s = s;
    };
    e.prototype = {
        commit: function () {
            this.s.setRow([this.k, '' + this.v], this.r);
        },
        update: function (v) {
            this.v = v;
        },
        updateWithCommit: function (v) {
            this.v = v;
            this.s.setRow([this.k, '' + this.v], this.r);
        },
        get: function () {
            return this.v;
        },
    };
    var u = function (ss) {
        this.inner = ss;
        this.entities = null;
        this.next = 0;
        this._readEntities();
    };
    u.prototype = {
        _readEntities: function () {
            var rows = this.inner.getAllRows();
            var indexes = {};
            for (var i = 1; i < rows.length; i++) {
                indexes[rows[i][0]] = new e(
                    rows[i][0],
                    rows[i][1],
                    i + 1,
                    this.inner
                );
            }
            this.entities = indexes;
            this.next = rows.length;
        },
        getEntity: function (key) {
            var r = this.entities[key];
            if (!r) r = new e(
                key,
                '',
                ++this.next,
                this.inner
            );
            return r;
        }
    };
    return u;
})();



var settings = {
    spreadsheet_id: '***************************************', // スプレッドシートのURLに付いてる長い奴
    sheet_meta: 'meta', // (データ管理用)↑にシートを追加し、付けたシート名を書いておく
    sheet_logs: 'logs', // (ログ収集先)↑にシートを追加し、付けたシート名を書いておく
    store: 'https://store.nintendo.co.jp/category/NINTENDOSWITCH/HAC_S_KAYAA.html',
    // https://discordapp.com/api/webhooks/' + discord_wh_id + '/' + discord_wh_token
    discord_wh_id : '000000000000000000',
    discord_wh_token : '********************************************************************'
};

function myFunction() {
    var discord = new Discord(
        settings.discord_wh_id,
        settings.discord_wh_token
    );
    var meta = new KVS(new SpreadSheet(settings.spreadsheet_id, settings.sheet_meta));
    var data = new SpreadSheet(settings.spreadsheet_id, settings.sheet_logs);
    var prev_state_cache = meta.getEntity('state');
    var prev_state_value = prev_state_cache.get().toLowerCase();
    var prev_state = prev_state_value == 'true';
    var resp = UrlFetchApp.fetch(settings.store, {'method': 'get'});
    var doc = resp.getContentText();
    var btn_txt = doc.split('<div class="add_area">')[1].split('</div>')[0].trim().replace(/<[^>]*>/g,'');
    var state = btn_txt != 'SOLD OUT'; // button message
    if(state != prev_state){
        data.addRow([''+(new Date()), state]);
        discord.send(state ? ('再販 at '+settings.store) : '完売');
        prev_state_cache.updateWithCommit(state ? 'true' : 'false');
    }
    meta.getEntity('updated').updateWithCommit((''+new Date()));
}