/*REMEMBER 2 add KARLKODER + LIB :-)*/

const KEYWORDS = [
    "Array",
    "ArrayBuffer",
    "BigInt",
    "Blob",
    "CaretPosition",
    "Date",
    "Error",
    "FormData",
    "Headers",
    "Infinity",
    "Int8Array",
    "JSON",
    "Map",
    "Math",
    "NaN",
    "Number",
    "Object",
    "Promise",
    "ReadableStream",
    "RegExp",
    "Request",
    "Response",
    "Set",
    "String",
    "Symbol",
    "TextDecoder",
    "TextEncoder",
    "URL",
    "Uint8Array",
    "WebSocket",
    "Worker",
    "WritableStream",
    "alert",
    "atob",
    "blur",
    "btoa",
    "crypto",
    "decodeURI",
    "decodeURIComponent",
    "encodeURI",
    "encodeURIComponent",
    "fetch",
    "isFinite",
    "isNaN",
    "length",
    "localStorage",
    "navigator",
    "parseFloat",
    "parseInt",
    "sessionStorage",
    "undefined",
    "window",
    "globalThis",
];

export class TextCompleter {
    getCompletions(_editor, session, pos, _, callback) {
        // Check if user has written "lib."
        const line = session.doc["$lines"][pos.row].slice(0, pos.column);
        if (line.match(/lib\.\w*$/)) {
            callback(null, []);
            return;
        }

        const locals = [];
        for (let i = 0; i <= pos.row; ++i) {
            const line = session.doc["$lines"][i].trim();
            if (line.startsWith("const ") || line.startsWith("let ")) {
                const [_, name] = line.match(/^\w+ (\w+)/);
                locals.push(name);
                continue;
            }

            if (line.startsWith("function ")) {
                const lineNoFunction = line.slice("function ".length);
                const [_, name] = lineNoFunction.match(/^\s*(\w+)/);
                locals.push(name);

                let local = "";
                const start = lineNoFunction.indexOf(name) + name.length;
                for (let i = start; i < lineNoFunction.length; ++i) {
                    if (lineNoFunction[i].trim() === "") {
                        continue;
                    }
                    const ch = lineNoFunction[i];
                    if (["{", "=", "}", "(", ")", "[", "]"].includes(ch)) {
                        continue;
                    }
                    if (ch === ",") {
                        locals.push(local);
                        local = "";
                        continue;
                    }
                    local += ch;
                }
                if (local.trim() !== "") {
                    locals.push(local);
                }

                continue;
            }
        }

        const wordList = []
            .concat(locals.map((word) => ({
                name: word,
                value: word,
                score: 0,
                meta: "local",
            })))
            .concat(KEYWORDS.map((word) => ({
                name: word,
                value: word,
                score: 0,
                meta: "keyword",
            })));

        return callback(null, wordList);
    }
}