const fs = require('fs');
const export_bytes = fs.readFileSync(__dirname + '/table_export.wasm');
const test_bytes = fs.readFileSync(__dirname + '/table_test.wasm');

let i = 0;
let increment = () => {
    i++;
    return i;
}

let decrement = () => {
    i--;
    return i;
}

const importObject = {
    js: {
        tbl: null,
        increment: increment,
        decrement: decrement,
        wasm_increment: null,
        wasm_decrement: null
    }
};

(async () => {
    let table_exp_obj = await WebAssembly.instantiate(
        new Uint8Array(export_bytes),
        importObject
    );

    importObject.js.tbl = table_exp_obj.instance.exports.tbl;

    importObject.js.wasm_increment = 
        table_exp_obj.instance.exports.increment;

    importObject.js.wasm_decrement =
        table_exp_obj.instance.exports.decrement;

    let obj = await WebAssembly.instantiate(
        new Uint8Array(test_bytes),
        importObject
    );

    // use destructuring 
    ({ js_table_test, js_import_test,
       wasm_table_test, wasm_import_test} = obj.instance.exports);

    i = 0;
    let start = Date.now();
    js_table_test();
    let time = Date.now() - start;
    console.log('js_table_test time: ' + time);

    i = 0;
    start = Date.now();
    js_import_test();
    time = Date.now() - start;
    console.log('js_import_test time: ' + time);

    i = 0;
    start = Date.now();
    wasm_table_test();
    time = Date.now() - start;
    console.log('wasm_table_test time: ' + time);

    i = 0;
    start = Date.now();
    wasm_import_test();
    time = Date.now() - start;
    console.log('wasm_import_test time: ' + time);
})();