// Copyright 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

/**
 * Handles DumpDatabase tab for syncfs-internals.
 */
var DumpDatabase = (function() {
'use strict';

var DumpDatabase = {};

/**
 * Get the database dump.
 */
function getDatabaseDump() {
  chrome.send('getDatabaseDump');
}

/**
 * Creates an element named |elementName| containing the content |text|.
 * @param {string} elementName Name of the new element to be created.
 * @param {string} text Text to be contained in the new element.
 * @return {HTMLElement} The newly created HTML element.
 */
function createElementFromText(elementName, text) {
  var element = document.createElement(elementName);
  element.appendChild(document.createTextNode(text));
  return element;
}

/**
 * Creates a table by filling |header| and |body|.
 * @param {HTMLElement} div The outer container of the table to be renderered.
 * @param {HTMLElement} header The table header element to be fillied by
 *     this function.
 * @param {HTMLElement} body The table body element to be filled by this
 *     function.
 * @param {Array} databaseDump List of dictionaries for the database dump.
 *     The first element must have metadata of the entry.
 *     The remaining elements must be dictionaries for the database dump,
 *     which can be iterated using the 'keys' fields given by the first
 *     element.
 */
function createDatabaseDumpTable(div, header, body, databaseDump) {
  var metadata = databaseDump.shift();
  div.appendChild(createElementFromText('h3', metadata['title']));

  var tr = document.createElement('tr');
  for (var i = 0; i < metadata.keys.length; ++i)
    tr.appendChild(createElementFromText('td', metadata.keys[i]));
  header.appendChild(tr);

  for (var i = 0; i < databaseDump.length; i++) {
    var entry = databaseDump[i];
    var tr = document.createElement('tr');
    for (var k = 0; k < metadata.keys.length; ++k)
      tr.appendChild(createElementFromText('td', entry[metadata.keys[k]]));
    body.appendChild(tr);
  }
}

/**
 * Handles callback from onGetDatabaseDump.
 * @param {Array} databaseDump List of lists for the database dump.
 */
DumpDatabase.onGetDatabaseDump = function(databaseDump) {
  var placeholder = $('dump-database-placeholder');
  placeholder.innerHTML = '';
  for (var i = 0; i < databaseDump.length; ++i) {
    var div = document.createElement('div');
    var table = document.createElement('table');
    var header = document.createElement('thead');
    var body = document.createElement('tbody');
    createDatabaseDumpTable(div, header, body, databaseDump[i]);
    table.appendChild(header);
    table.appendChild(body);
    div.appendChild(table);
    placeholder.appendChild(div);
  }
}

function main() {
  getDatabaseDump();
  $('refresh-database-dump').addEventListener('click', getDatabaseDump);
}

document.addEventListener('DOMContentLoaded', main);
return DumpDatabase;
})();