From 6e0e1bbb41a56b9a31f8edf60dc6516b60e55c6c Mon Sep 17 00:00:00 2001
From: DL6ER <dl6er@dl6er.de>
Date: Mon, 23 Nov 2020 13:35:40 +0100
Subject: [PATCH] Add button to remove dynamic DHCP leases. They are
 immediately removed both from FTL and the dhcp.leases file (FTL takes care of
 updating the file!) WITHOUT the need for a restart of the DHCP/DNS resolver.

Signed-off-by: DL6ER <dl6er@dl6er.de>
---
 api_FTL.php                    |  7 ++++++
 scripts/pi-hole/js/settings.js | 46 ++++++++++++++++++++++++++++++++++
 settings.php                   |  3 +++
 3 files changed, 56 insertions(+)

diff --git a/api_FTL.php b/api_FTL.php
index daf72307d..85227dd7a 100644
--- a/api_FTL.php
+++ b/api_FTL.php
@@ -416,6 +416,13 @@
 		$data = array_merge($data, $result);
 	}
 
+	if (isset($_GET['delete_lease']) && $auth)
+	{
+		sendRequestFTL("delete-lease ".$_GET['delete_lease']);
+		$return = getResponseFTL();
+		$data["delete_lease"] = $return[0];
+	}
+
 	disconnectFTL();
 }
 ?>
diff --git a/scripts/pi-hole/js/settings.js b/scripts/pi-hole/js/settings.js
index c50c7554e..6853e0c75 100644
--- a/scripts/pi-hole/js/settings.js
+++ b/scripts/pi-hole/js/settings.js
@@ -6,6 +6,7 @@
  *  Please see LICENSE file for your rights under this license. */
 
 /* global utils:false */
+var token = $("#token").text();
 
 $(function () {
   $("[data-static]").on("click", function () {
@@ -283,3 +284,48 @@ $(function () {
     localStorage.setItem("barchart_chkbox", bargraphs.prop("checked"));
   });
 });
+
+// Delete dynamic DHCP lease
+$('button[id="removedynamic"]').on("click", function () {
+  var tr = $(this).closest("tr");
+  var ipaddr = utils.escapeHtml(tr.children("#IP").text());
+  var name = utils.escapeHtml(tr.children("#HOST").text());
+  var ipname = name + " (" + ipaddr + ")";
+
+  utils.disableAll();
+  utils.showAlert("info", "", "Deleting DHCP lease...", ipname);
+  $.ajax({
+    url: "api.php",
+    method: "get",
+    dataType: "json",
+    data: {
+      delete_lease: ipaddr,
+      token: token
+    },
+    success: function (response) {
+      utils.enableAll();
+      if (response.delete_lease.startsWith("OK")) {
+        utils.showAlert(
+          "success",
+          "far fa-trash-alt",
+          "Successfully deleted DHCP lease for ",
+          ipname
+        );
+        // Remove column on success
+        tr.remove();
+        // We have to hide the tooltips explicitly or they will stay there forever as
+        // the onmouseout event does not fire when the element is already gone
+        $.each($(".tooltip"), function () {
+          $(this).remove();
+        });
+      } else {
+        utils.showAlert("error", "Error while deleting DHCP lease for " + ipname, response);
+      }
+    },
+    error: function (jqXHR, exception) {
+      utils.enableAll();
+      utils.showAlert("error", "Error while deleting DHCP lease for " + ipname, jqXHR.responseText);
+      console.log(exception); // eslint-disable-line no-console
+    }
+  });
+});
diff --git a/settings.php b/settings.php
index a17309e3c..dfaceacd8 100644
--- a/settings.php
+++ b/settings.php
@@ -717,6 +717,9 @@ function convertseconds($argument)
                                                             <td id="IP" data-order="<?php echo bin2hex(inet_pton($lease["IP"])); ?>"><?php echo $lease["IP"]; ?></td>
                                                             <td id="HOST"><?php echo $lease["host"]; ?></td>
                                                             <td>
+                                                                <button type="button" class="btn btn-danger btn-xs" id="removedynamic">
+                                                                    <span class="fas fas fa-trash-alt"></span>
+                                                                </button>
                                                                 <button type="button" id="button" class="btn btn-warning btn-xs" data-static="alert">
                                                                     <span class="fas fas fa-file-import"></span>
                                                                 </button>