const fs = require('fs');
let average = (array) => array.reduce((a, b) => a + b) / array.length;

function tryrem(file) {
    try {
        data = JSON.parse(fs.readFileSync(file));
    } catch (e) {
        console.log("Failed to save, removing file");
        fs.unlinkSync(file);
        tryrem(file);
    }
}

module.exports = (percs, words, file, silent) => {
    if (typeof silent == "undefined") {
        silent = false;
    }

    tryrem(file);

    keys = Object.keys(percs);
    keys2 = Object.keys(data);

    for (var i=0; i<keys.length; i++) {
        key = keys[i];

        if (key !== "total") {
            data[key].entries.push(percs[key]);
        }
    }

    if (!silent) console.log("Saving words list...");
    newwords = [];
    words.forEach((word) => {
        if (!data["words"].includes(word)) {
            newwords.push(word);
        }
    })
    data["words"] = [...data["words"], ...newwords];

    if (!silent) console.log("Recalculating averages...");

    for (var i=0; i<keys2.length; i++) {
        key = keys2[i];

        if (key !== "total" && key !== "words") {
            data[key].average = average(data[key].entries);
        }
    }

    fs.writeFileSync(file, JSON.stringify(data));
}