<style>
#backup-status th { text-align: center; }
#backup-status tr.full-backup td { font-weight: bold; }
</style>

<h2>Backup Status</h2>

<p>The box makes an incremental backup each night. By default the backup is stored on the machine itself, but you can also store it on S3-compatible services like Amazon Web Services (AWS).</p>

<h3>Configuration</h3>

<form class="form-horizontal" role="form" onsubmit="set_custom_backup(); return false;">
  <div class="form-group">
    <label for="backup-target-type" class="col-sm-2 control-label">Backup to:</label>
    <div class="col-sm-2">
      <select class="form-control" rows="1" id="backup-target-type" onchange="toggle_form()">
        <option value="off">Nowhere (Disable Backups)</option>
        <option value="local">{{hostname}}</option>
        <option value="rsync">rsync</option>
        <option value="s3">S3 (Amazon or compatible) </option>
        <option value="b2">Backblaze B2</option>
      </select>
    </div>
  </div>
  <!-- LOCAL BACKUP -->
  <div class="form-group backup-target-local">
    <div class="col-sm-10 col-sm-offset-2">
      <p>Backups are stored on this machine&rsquo;s own hard disk. You are responsible for periodically using SFTP (FTP over SSH) to copy the backup files from <tt class="backup-location"></tt> to a safe location. These files are encrypted, so they are safe to store anywhere.</p>
      <p>Separately copy the encryption password from <tt class="backup-encpassword-file"></tt> to a safe and secure location. You will need this file to decrypt backup files.</p>
    </div>
  </div>
  <!-- RSYNC BACKUP -->
  <div class="form-group backup-target-rsync">
    <div class="col-sm-10 col-sm-offset-2">

      <p>Backups synced to a remote machine using rsync over SSH, with local
      copies in <tt class="backup-location"></tt>. These files are encrypted, so
      they are safe to store anywhere.</p> <p>Separately copy the encryption
      password from <tt class="backup-encpassword-file"></tt> to a safe and
      secure location. You will need this file to decrypt backup files.</p>

    </div>
  </div>
  <div class="form-group backup-target-rsync">
    <label for="backup-target-rsync-host" class="col-sm-2 control-label">Hostname</label>
    <div class="col-sm-8">
      <input type="text" placeholder="hostname.local" class="form-control" rows="1" id="backup-target-rsync-host">
      <div class="small" style="margin-top: 2px">
	The hostname at your rsync provider, e.g. <tt>da2327.rsync.net</tt>.  Optionally includes a colon
	and the provider's non-standard ssh port number, e.g. <tt>u215843.your-storagebox.de:23</tt>. 
      </div>
    </div>
  </div>
  <div class="form-group backup-target-rsync">
    <label for="backup-target-rsync-path" class="col-sm-2 control-label">Path</label>
    <div class="col-sm-8">
        <input type="text" placeholder="/backups/{{hostname}}" class="form-control" rows="1" id="backup-target-rsync-path">
    </div>
  </div>
  <div class="form-group backup-target-rsync">
    <label for="backup-target-rsync-user" class="col-sm-2 control-label">Username</label>
    <div class="col-sm-8">
      <input type="text" class="form-control" rows="1" id="backup-target-rsync-user">
    </div>
  </div>
  <div class="form-group backup-target-rsync">
    <label for="ssh-pub-key" class="col-sm-2 control-label">Public SSH Key</label>
    <div class="col-sm-8">
      <input type="text" class="form-control" rows="1" id="ssh-pub-key" readonly>
      <div class="small" style="margin-top: 2px">
        Copy the Public SSH Key above, and paste it within the <tt>~/.ssh/authorized_keys</tt>
        of target user on the backup server specified above. That way you'll enable secure and
        passwordless authentication from your mail-in-a-box server and your backup server.
      </div>
    </div>
  </div>
  <!-- S3 BACKUP -->
  <div class="form-group backup-target-s3">
    <div class="col-sm-10 col-sm-offset-2">
      <p>Backups are stored in an S3-compatible bucket. You must have an AWS or other S3 service account already.</p>
      <p>You MUST manually copy the encryption password from <tt class="backup-encpassword-file"></tt> to a safe and secure location. You will need this file to decrypt backup files. It is <b>NOT</b> stored in your S3 bucket.</p>
    </div>
  </div>
  <div class="form-group backup-target-s3">
    <label for="backup-target-s3-host-select" class="col-sm-2 control-label">S3 Region</label>
    <div class="col-sm-8">
      <select class="form-control" rows="1" id="backup-target-s3-host-select">
        {% for name, host in backup_s3_hosts %}
          <option value="{{host}}">{{name}}</option>
        {% endfor %}
        <option value="other">Other (non AWS)</option>
      </select>
    </div>
  </div>
  <div class="form-group backup-target-s3">
    <label for="backup-target-s3-host" class="col-sm-2 control-label">S3 Host / Endpoint</label>
    <div class="col-sm-8">
      <input type="text" placeholder="Endpoint" class="form-control" rows="1" id="backup-target-s3-host">
    </div>
  </div>
  <div class="form-group backup-target-s3">
    <label for="backup-target-s3-path" class="col-sm-2 control-label">S3 Path</label>
    <div class="col-sm-8">
      <input type="text" placeholder="your-bucket-name/backup-directory" class="form-control" rows="1" id="backup-target-s3-path">
    </div>
  </div>
  <div class="form-group backup-target-s3">
    <label for="backup-target-user" class="col-sm-2 control-label">S3 Access Key</label>
    <div class="col-sm-8">
      <input type="text" class="form-control" rows="1" id="backup-target-user">
    </div>
  </div>
  <div class="form-group backup-target-s3">
    <label for="backup-target-pass" class="col-sm-2 control-label">S3 Secret Access Key</label>
    <div class="col-sm-8">
      <input type="text" class="form-control" rows="1" id="backup-target-pass">
    </div>
  </div>
  <!-- Backblaze -->
  <div class="form-group backup-target-b2">
      <div class="col-sm-10 col-sm-offset-2">
        <p>Backups are stored in a <a href="https://www.backblaze.com/" target="_blank" rel="noreferrer">Backblaze</a> B2 bucket. You must have a Backblaze account already.</p>
        <p>You MUST manually copy the encryption password from <tt class="backup-encpassword-file"></tt> to a safe and secure location. You will need this file to decrypt backup files. It is NOT stored in your Backblaze B2 bucket.</p>
      </div>
  </div>
  <div class="form-group backup-target-b2">
      <label for="backup-target-b2-user" class="col-sm-2 control-label">B2 Application KeyID</label>
      <div class="col-sm-8">
        <input type="text" class="form-control" rows="1" id="backup-target-b2-user">
      </div>
  </div>
  <div class="form-group backup-target-b2">
      <label for="backup-target-b2-pass" class="col-sm-2 control-label">B2 Application Key</label>
      <div class="col-sm-8">
        <input type="text" class="form-control" rows="1" id="backup-target-b2-pass">
      </div>
  </div>
  <div class="form-group backup-target-b2">
      <label for="backup-target-b2-bucket" class="col-sm-2 control-label">B2 Bucket</label>
      <div class="col-sm-8">
        <input type="text" class="form-control" rows="1" id="backup-target-b2-bucket">
      </div>
  </div>
  <!-- Common -->
  <div class="form-group backup-target-local backup-target-rsync backup-target-s3 backup-target-b2">
    <label for="min-age" class="col-sm-2 control-label">Retention Days:</label>
    <div class="col-sm-8">
      <input type="number" class="form-control" rows="1" id="min-age">
      <div class="small" style="margin-top: 2px">This is the minimum time backup data is kept for. The box makes an incremental backup most nights, which requires that previous backups back to the most recent full backup be preserved, so backup data is often kept much longer than this setting. Full backups are made periodically when the incremental backup data size exceeds a limit.</div>
    </div>
  </div>
  <div class="form-group">
    <div class="col-sm-offset-2 col-sm-10">
      <button id="set-s3-backup-button" type="submit" class="btn btn-primary">Save</button>
    </div>
  </div>
</form>

<h3>Available backups</h3>

<p>The backup location currently contains the backups listed below. The total size of the backups is currently <span id="backup-total-size"></span>.</p>

<table id="backup-status" class="table" style="width: auto">
  <thead>
    <th colspan="2">When</th>
    <th>Type</th>
    <th>Size</th>
    <th>Deleted in...</th>
  </thead>
  <tbody>
  </tbody>
</table>
<script>

function toggle_form() {
  var target_type = $("#backup-target-type").val();
  $(".backup-target-local, .backup-target-rsync, .backup-target-s3, .backup-target-b2").hide();
  $(".backup-target-" + target_type).show();

  init_inputs(target_type);
}

function nice_size(bytes) {
  var powers = ['bytes', 'KB', 'MB', 'GB', 'TB'];
  while (true) {
    if (powers.length == 1) break;
    if (bytes < 1000) break;
    bytes /= 1024;
    powers.shift();
  }
  // round to have three significant figures but at most one decimal place
  if (bytes >= 100)
    bytes = Math.round(bytes)
  else
    bytes = Math.round(bytes*10)/10;
  return bytes + " " + powers[0];
}

function show_system_backup() {
  show_custom_backup()

  $('#backup-status tbody').html("<tr><td colspan='2' class='text-muted'>Loading...</td></tr>")
  api(
    "/system/backup/status",
    "GET",
    { },
    function(r) {
      if (r.error) {
          show_modal_error("Backup Error", $("<pre/>").text(r.error));
          return;
      }

      $('#backup-status tbody').html("");
      var total_disk_size = 0;

      if (typeof r.backups == "undefined") {
        var tr = $('<tr><td colspan="3">Backups are turned off.</td></tr>');
        $('#backup-status tbody').append(tr);
        return;
      } else if (r.backups.length == 0) {
        var tr = $('<tr><td colspan="3">No backups have been made yet.</td></tr>');
        $('#backup-status tbody').append(tr);
      }

      for (var i = 0; i < r.backups.length; i++) {
        var b = r.backups[i];
        var tr = $('<tr/>');
        if (b.full) tr.addClass("full-backup");
        tr.append( $('<td/>').text(b.date_str) );
        tr.append( $('<td/>').text(b.date_delta + " ago") );
        tr.append( $('<td/>').text(b.full ? "full" : "increment") );
        tr.append( $('<td style="text-align: right"/>').text( nice_size(b.size)) );
        if (b.deleted_in)
          tr.append( $('<td/>').text(b.deleted_in) );
        else
          tr.append( $('<td class="text-muted">unknown</td>') );
        $('#backup-status tbody').append(tr);

        total_disk_size += b.size;
      }

      total_disk_size += r.unmatched_file_size;
      $('#backup-total-size').text(nice_size(total_disk_size));
    })
}

function show_custom_backup() {
    $(".backup-target-local, .backup-target-rsync, .backup-target-s3, .backup-target-b2").hide();
    api(
      "/system/backup/config",
      "GET",
      { },
      function(r) {
        $("#backup-target-user").val(r.target_user);
        $("#backup-target-pass").val(r.target_pass);
        $("#min-age").val(r.min_age_in_days);
        $(".backup-location").text(r.file_target_directory);
        $(".backup-encpassword-file").text(r.enc_pw_file);
        $("#ssh-pub-key").val(r.ssh_pub_key);

        if (r.target == "file://" + r.file_target_directory) {
          $("#backup-target-type").val("local");
        } else if (r.target == "off") {
          $("#backup-target-type").val("off");
        } else if (r.target.substring(0, 8) == "rsync://") {
          const spec = url_split(r.target);
          $("#backup-target-type").val(spec.scheme);
	  $("#backup-target-rsync-user").val(spec.user);
	  $("#backup-target-rsync-host").val(spec.host);
	  $("#backup-target-rsync-path").val(spec.path);
        } else if (r.target.substring(0, 5) == "s3://") {
          $("#backup-target-type").val("s3");
          var hostpath = r.target.substring(5).split('/');
          var host = hostpath.shift();
          $("#backup-target-s3-host-select").val(host);
          $("#backup-target-s3-host").val(host);
          $("#backup-target-s3-path").val(hostpath.join('/'));
        } else if (r.target.substring(0, 5) == "b2://") {
          $("#backup-target-type").val("b2");
          var targetPath = r.target.substring(5);
          var b2_application_keyid = targetPath.split(':')[0];
          var b2_applicationkey = targetPath.split(':')[1].split('@')[0];
          var b2_bucket = targetPath.split('@')[1];
          $("#backup-target-b2-user").val(b2_application_keyid);
          $("#backup-target-b2-pass").val(b2_applicationkey);
          $("#backup-target-b2-bucket").val(b2_bucket);
        }
        toggle_form()
      })
}

function set_custom_backup() {
  var target_type = $("#backup-target-type").val();
  var target_user = $("#backup-target-user").val();
  var target_pass = $("#backup-target-pass").val();

  var target;
  if (target_type == "local" || target_type == "off")
    target = target_type;
  else if (target_type == "s3")
    target = "s3://" + $("#backup-target-s3-host").val() + "/" + $("#backup-target-s3-path").val();
  else if (target_type == "rsync") {
    target = "rsync://" + $("#backup-target-rsync-user").val() + "@" + $("#backup-target-rsync-host").val()
                                                                + "/" + $("#backup-target-rsync-path").val();
    target_user = '';
  } else if (target_type == "b2") {
    target = 'b2://' + $('#backup-target-b2-user').val() + ':' + $('#backup-target-b2-pass').val()
        + '@' + $('#backup-target-b2-bucket').val()
    target_user = '';
    target_pass = '';
  }


  var min_age = $("#min-age").val();
  api(
    "/system/backup/config",
    "POST",
    {
      target: target,
      target_user: target_user,
      target_pass: target_pass,
      min_age: min_age
    },
    function(r) {
      // use .text() --- it's a text response, not html
      show_modal_error("Backup configuration", $("<p/>").text(r), function() { if (r == "OK") show_system_backup(); }); // refresh after modal on success
    },
    function(r) {
      // use .text() --- it's a text response, not html
      show_modal_error("Backup configuration", $("<p/>").text(r));
    });
  return false;
}

function init_inputs(target_type) {
  function set_host(host) {
    if(host !== 'other') {
      $("#backup-target-s3-host").val(host);
    } else {
      $("#backup-target-s3-host").val('');
    }
  }
  if (target_type == "s3") {
    $('#backup-target-s3-host-select').off('change').on('change', function() {
      set_host($('#backup-target-s3-host-select').val());
    });
    set_host($('#backup-target-s3-host-select').val());
  }
}

// Return a two-element array of the substring preceding and the substring following
// the first occurence of separator in string. Return [undefined, string] if the
// separator does not appear in string.
const split1_rest = (string, separator) => {
    const index = string.indexOf(separator);
    return (index >= 0) ? [string.substring(0, index), string.substring(index + separator.length)] : [undefined, string];
};

// Note: The manifest JS URL class does not work in some security-conscious
// settings, e.g. Brave browser, so we roll our own that handles only what we need.
//
// Use greedy separator parsing to get parts of a MIAB backup target url.
// Note: path will not include a leading forward slash '/'
const url_split = url => {
    const [ scheme, scheme_rest ] = split1_rest(url, '://');
    const [ user, user_rest ] = split1_rest(scheme_rest, '@');
    const [ host, path ] = split1_rest(user_rest, '/');

    return {
	scheme,
	user,
	host,
	path,
    }
};
  
</script>
