From ea09a18d3f05b20ff7f1ec25aea74f32d68ca5e0 Mon Sep 17 00:00:00 2001
From: Anatoly Bubenkov <bubenkoff@gmail.com>
Date: Thu, 3 Nov 2022 23:43:08 +0100
Subject: [PATCH] sms-forward: support hooks

---
 doc/sms-forward.md    | 28 ++++++++++++++++++++++++++++
 global-config         |  8 ++++++++
 global-config.changes |  1 +
 global-functions      |  2 +-
 sms-forward           | 22 ++++++++++++++++++++++
 5 files changed, 60 insertions(+), 1 deletion(-)

diff --git a/doc/sms-forward.md b/doc/sms-forward.md
index 3d9974d..73248eb 100644
--- a/doc/sms-forward.md
+++ b/doc/sms-forward.md
@@ -35,11 +35,39 @@ You have to enable receiving of SMS:
 
     /tool/sms/set receive-enabled=yes;
 
+The configuration goes to `global-config-overlay`, this is the only parameter:
+
+* `SmsForwardHooks`: an array with pre-defined hooks, where each hook consists
+  of `match` (which is matched against the received message), `allowed-number`
+  (which is matched against the sending phone number or name) and `command`.
+  For `match` and `allowed-number` regular expressions are supported.
+
 Notification settings are required for
 [e-mail](mod/notification-email.md),
 [matrix](mod/notification-matrix.md) and/or
 [telegram](mod/notification-telegram.md).
 
+Tips & Tricks
+-------------
+
+### Order new volume
+
+Most broadband providers include a volume limit for their data plans. The
+hook functionality can be used to order new volume automatically.
+
+Let's assume an imaginary provider **ABC** sends a message when the available
+volume is about to deplete. The message is sent from `ABC` and the text
+contains the string `80%`. New volume can be ordered by sending a SMS back to
+the phone number `1234` with the text `data-plan`.
+
+    :global SmsForwardHooks {
+      { match="80%";
+        allowed-number="ABC";
+        command="/tool/sms/send lte1 phone-number=1234 message=\"data-plan\";" };
+    };
+
+Adjust the values to your own needs.
+
 See also
 --------
 
diff --git a/global-config b/global-config
index d4ed298..fded46f 100644
--- a/global-config
+++ b/global-config
@@ -147,6 +147,14 @@
 # add more here...
 };
 
+# Run commands by hooking into SMS forward.
+:global SmsForwardHooks {
+  { match="magic string";
+    allowed-number="12345678";
+    command="/system/script/run ..." };
+# add more here...
+};
+
 # This is the address used to send gps data to.
 :global GpsTrackUrl "https://example.com/index.php";
 
diff --git a/global-config.changes b/global-config.changes
index 216cfc6..357dede 100644
--- a/global-config.changes
+++ b/global-config.changes
@@ -94,6 +94,7 @@
   83="Introduced new setting to disable news and change notifications, dropped version from configuration.";
   84="Support for e-mail notifications moved to a module. It is installed automatically if required.";
   85="Dropped 'netwatch-syslog', filtering in firewall is advised.";
+  86="Added support for hooks in 'sms-forward'. This now provides similar functionality to 'sms-action', but is more flexible.";
 };
 
 # Migration steps to be applied on script updates
diff --git a/global-functions b/global-functions
index d25d21d..0c584b7 100644
--- a/global-functions
+++ b/global-functions
@@ -10,7 +10,7 @@
 :local 0 "global-functions";
 
 # expected configuration version
-:global ExpectedConfigVersion 85;
+:global ExpectedConfigVersion 86;
 
 # global variables not to be changed by user
 :global GlobalFunctionsReady false;
diff --git a/sms-forward b/sms-forward
index 8dce464..802da48 100644
--- a/sms-forward
+++ b/sms-forward
@@ -1,6 +1,7 @@
 #!rsc by RouterOS
 # RouterOS script: sms-forward
 # Copyright (c) 2013-2023 Christian Hesse <mail@eworm.de>
+#                         Anatoly Bubenkov <bubenkoff@gmail.com>
 # https://git.eworm.de/cgit/routeros-scripts/about/COPYING.md
 #
 # forward SMS to e-mail
@@ -11,12 +12,14 @@
 :while ($GlobalFunctionsReady != true) do={ :delay 500ms; }
 
 :global Identity;
+:global SmsForwardHooks;
 
 :global IfThenElse;
 :global LogPrintExit2;
 :global ScriptLock;
 :global SendNotification2;
 :global SymbolForNotification;
+:global ValidateSyntax;
 :global WaitFullyConnected;
 
 $ScriptLock $0;
@@ -45,6 +48,25 @@ $WaitFullyConnected;
     } else={
       :set Messages ($Messages . "\n\nOn " . $SmsVal->"timestamp" . \
           " type " . $SmsVal->"type" . ":\n" . $SmsVal->"message");
+      :foreach Hook in=$SmsForwardHooks do={
+        :if ($Phone~($Hook->"allowed-number") && ($SmsVal->"message")~($Hook->"match")) do={
+          :if ([ $ValidateSyntax ($Hook->"command") ] = true) do={
+            $LogPrintExit2 info $0 ("Running hook '" . $Hook->"match" . "': " . \
+                $Hook->"command") false;
+            :do {
+              [ :parse ($Hook->"command") ];
+              :set Messages ($Messages . "\n\nRan hook '" . $Hook->"match" . "':\n" . \
+                  $Hook->"command");
+            } on-error={
+              $LogPrintExit2 warning $0 ("The code for hook '" . $Hook->"match" . \
+                  "' failed to run!") false;
+            }
+          } else={
+            $LogPrintExit2 warning $0 ("The code for hook '" . $Hook->"match" . \
+                "' failed syntax validation!") false;
+          }
+        }
+      }
       :set Delete ($Delete, $Sms);
     }
   }