/*
    List cluster files - the launcher

    Submits list_files.job.agi as one cluster job, waits for it and returns
    its output: every file under cluster:/ with its size and extension, and
    a size total per extension.

    Optional parameters, in the URL query or a form body:
        root   folder to list, default cluster:/
        limit  maximum files in the list, default 5000

    Keep list_files.job.agi in the same folder as this file.
*/

requirelib("cluster");

//Read a request parameter. A script run as a Serverless endpoint gets the
//request through getPara() (URL query) and postPara() (form body); a WebApp
//backend script gets its POST fields as global variables instead.
function requestParam(name) {
    var v = null;
    if (typeof getPara === "function") {
        v = getPara(name);
    }
    if ((v === null || v === "") && typeof postPara === "function") {
        v = postPara(name);
    }
    if (v === null || v === "") {
        var globalScope = (function () { return this; })();
        v = (typeof globalScope[name] === "string") ? globalScope[name] : "";
    }
    return v === null ? "" : String(v);
}

function main() {
    if (!cluster.inCluster()) {
        return { error: "This node is not part of a cluster. Create or join one in System Settings > Cluster Settings." };
    }

    var args = {};
    if (requestParam("root") !== "") {
        args.root = requestParam("root");
    }
    if (parseInt(requestParam("limit")) > 0) {
        args.limit = parseInt(requestParam("limit"));
    }

    var id = cluster.jobs.submit({
        name: "List cluster files",
        script: "list_files.job.agi",
        args: args,
        timeout: 600
    });

    var rec;
    try {
        rec = cluster.jobs.wait(id, 120);
    } catch (e) {
        rec = cluster.jobs.status(id);
        return { job: id, status: rec.state.status, note: "Still running. Follow it on System Settings > Cluster Jobs." };
    }

    if (rec.state.status !== "succeeded") {
        return { job: id, status: rec.state.status, error: rec.state.error || rec.state.reason || "" };
    }
    return rec.state.output;
}

sendJSONResp(JSON.stringify(main()));