#!/usr/bin/env node

/*
 * Run all analytics reports output JSON to disk.
 *
 * Usage: analytics
 *
 * Defaults to printing JSON to STDOUT.
 *
 * --output: Output to a directory.
 * --publish: Publish to an S3 bucket.
 * --only: only run one report.
 * --slim: Where supported, use totals only (omit the `data` array).
 *         Only applies to JSON, and reports where "slim": true.
 * --csv: CSV instead of JSON.
 * --frequency: Limit to reports with this 'frequency' value.
 * --debug: print debug details on STDOUT
 */

var Analytics = require("../analytics"),
    config = require("../config"),
    fs = require("fs"),
    path = require('path'),
    async = require("async")
    csv = require("fast-csv");


// AWS credentials are looked for in env vars or in ~/.aws/config.
// AWS bucket and path need to be set in env vars mentioned in config.js.

var AWS = require("aws-sdk");

var publish = function(name, data, extension, options, callback) {
  if (options.debug) console.log("[" + name + "] Publishing to " + config.aws.bucket + "...");

  var mime = {".json": "application/json", ".csv": "text/csv"};

  new AWS.S3({params: {Bucket: config.aws.bucket}}).upload({
    Key: config.aws.path + "/" + name + extension,
    Body: data,
    ContentType: mime[extension],
    ACL: "public-read",
    CacheControl: "max-age=" + (config.aws.cache || 0)
  }, callback);
};


var run = function(options) {
  if (!options) options = {};
  if (options.debug) options.verbose = options.debug;
  if (options.verbose) options.debug = options.verbose;

  // can be overridden to only do one report
  var names;
  if (options.only)
    names = [options.only];
  else if (options.frequency) {
    names = [];
    var all = Object.keys(Analytics.reports);
    for (var i=0; i<all.length; i++) {
      if (Analytics.reports[all[i]].frequency == options.frequency)
        names.push(all[i]);
    }
  }

  else
    names = Object.keys(Analytics.reports);

  var eachReport = function(name, done) {
    var report = Analytics.reports[name];

    if (options.debug) console.log("\n[" + report.name + "] Fetching...");
    Analytics.query(report, function(err, data) {
        if (err) return console.log("ERROR AFTER QUERYING: " + err);

        if (options.debug) console.log("[" + report.name + "] Saving report data...");

        // CSV, see https://github.com/C2FO/fast-csv#formatting-functions
        if (options.csv) {
          csv.writeToString(data['data'], {headers: true}, function(err, data) {
            if (err) return console.log("ERROR AFTER CSV: " + JSON.stringify(err));

            writeReport(name, data, ".csv", done);
          });
        }

        // JSON
        else {
          // some reports can be slimmed down for direct rendering
          if (options.slim && report.slim) delete data.data;

          writeReport(name, JSON.stringify(data, null, 2), ".json", done);
        }
    });
  };

  var writeReport = function(name, output, extension, done) {
    var written = function(err) {
      if (err)
        console.error("ERROR AFTER WRITING: " + JSON.stringify(err));
      else if (options.debug)
        console.log("[" + name + "] Done.");
      done();
    };

    if (options.publish)
      publish(name, output, extension, options, written);

    else if (options.output && (typeof(options.output) == "string"))
      fs.writeFile(path.join(options.output, (name + extension)), output, written);

    else {
      // could be split on \n\n
      console.log(output + "\n");
      written();
    }
  };

  async.eachSeries(names, eachReport, function(err) {
    if (err) {
      console.error(err);
      process.exit(1);
    }

    if (options.debug) console.log("All done.");
  });
};

run(require('minimist')(process.argv.slice(2)));