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Add amazon link by ISBN
// ==UserScript==
// @name Bangumi-ISBN-Amazon-Link
// @namespace BIAL
// @description Add amazon link by ISBN
// @include /https?:\/\/(bgm|bangumi|chii)\.(tv|in)\/subject\/\d+$/
// @version 0.0.4
// @grant none
// ==/UserScript==
$('#infobox').html((function() {
var isbn = $('#infobox').html().match(/ISBN: <\/span\>([\dX\-]+)/)[1];
if(typeof isbn == "undefined") return $('#infobox').html();
isbn = isbn.replace(/\-/g, '');
if(isbn.length == 13) {
isbn = isbn.substr(3, 9);
var tmp = 0;
for(var i = 0; i <= 8; i++) {
tmp += parseInt(isbn[i]) * (10 - i);
}
tmp = 11 - (tmp % 11);
if(tmp == 10) tmp = "X";
if(tmp == 11) tmp = "0";
isbn += ("" + tmp);
}
return $('#infobox').html().replace(/ISBN: <\/span\>([\dX\-]+)/, 'ISBN: </span>$1 <a class="l" href="https://www.amazon.co.jp/dp/' + isbn + '" target="_blank">日本Amazon</a>');
}));