From 5a39c618ce56f95b6c4ce01de5ea0644e217423f Mon Sep 17 00:00:00 2001
From: Pim van Pelt <pim@ipng.nl>
Date: Sun, 4 Nov 2018 14:10:28 +0100
Subject: [PATCH] Allow LED and Relay logic level to be inverted

---
 include/main.h |  2 ++
 src/channel.c  | 15 ++++++++++-----
 2 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/include/main.h b/include/main.h
index b6c99b1..f36f93f 100644
--- a/include/main.h
+++ b/include/main.h
@@ -12,7 +12,9 @@
 struct channel_t {
   uint8_t button_gpio;
   uint8_t led_gpio;
+  bool    led_invert;
   uint8_t relay_gpio;
+  bool    relay_invert;
   bool    relay_state;
   double  button_last_change;
 };
diff --git a/src/channel.c b/src/channel.c
index 542fc22..a253dc0 100644
--- a/src/channel.c
+++ b/src/channel.c
@@ -57,6 +57,8 @@ bool channel_init(const char *fn) {
   // Traverse Array
   while ((h = json_next_elem(json, strlen(json), h, ".channels", &idx, &val)) != NULL) {
     int led = -1, relay = -1, button = -1;
+    bool led_invert = false;
+    bool relay_invert = false;
 
     LOG(LL_DEBUG, ("[%d]: [%.*s]", idx, val.len, val.ptr));
     if (val.len == 0 || !val.ptr) {
@@ -66,7 +68,7 @@ bool channel_init(const char *fn) {
       LOG(LL_ERROR, ("Incomplete Channel JSON: require 'led' and 'relay' and 'button' fields"));
       goto exit;
     }
-    LOG(LL_INFO, ("Channel[%d]: led=%d relay=%d button=%d ", idx, led, relay, button));
+    json_scanf(val.ptr, val.len, "{led:%d, led_invert:%B, relay:%d, relay_invert:%B, button:%d}", &led, &led_invert, &relay, &relay_invert, &button);
     if (!valid_gpio(led)) {
       LOG(LL_ERROR, ("LED GPIO (%d) out of bounds [%d,%d]", led, GPIO_MIN, GPIO_MAX));
       goto exit;
@@ -83,9 +85,12 @@ bool channel_init(const char *fn) {
       LOG(LL_ERROR, ("Too many channels (max is %d)", CHANNEL_MAX));
       goto exit;
     }
+    LOG(LL_INFO, ("Channel[%d]: led=%d%s relay=%d%s button=%d ", idx, led, led_invert?"(inverted)":"", relay, relay_invert?"(inverted)":"", button));
     s_channels[idx].button_gpio = button;
     s_channels[idx].relay_gpio  = relay;
+    s_channels[idx].relay_invert= relay_invert;
     s_channels[idx].led_gpio    = led;
+    s_channels[idx].led_invert  = led_invert;
   }
 
   ret = true;
@@ -103,12 +108,12 @@ exit:
 
       if (s_channels[idx].relay_gpio != GPIO_INVALID) {
         mgos_gpio_set_mode(s_channels[idx].relay_gpio, MGOS_GPIO_MODE_OUTPUT);
-        mgos_gpio_write(s_channels[idx].relay_gpio, s_channels[idx].relay_state);
+        mgos_gpio_write(s_channels[idx].relay_gpio, (s_channels[idx].relay_state + s_channels[idx].relay_invert)%2);
       }
 
       if (s_channels[idx].led_gpio != GPIO_INVALID) {
         mgos_gpio_set_mode(s_channels[idx].led_gpio, MGOS_GPIO_MODE_OUTPUT);
-        mgos_gpio_write(s_channels[idx].led_gpio, s_channels[idx].relay_state);
+        mgos_gpio_write(s_channels[idx].led_gpio, (s_channels[idx].relay_state + s_channels[idx].led_invert)%2);
       }
 
       if (s_channels[idx].button_gpio != GPIO_INVALID) {
@@ -187,10 +192,10 @@ void channel_set(int idx, bool state) {
   s_channels[idx].button_last_change = now;
   s_channels[idx].relay_state        = state;
   if (s_channels[idx].relay_gpio != GPIO_INVALID) {
-    mgos_gpio_write(s_channels[idx].relay_gpio, state);
+    mgos_gpio_write(s_channels[idx].relay_gpio, (s_channels[idx].relay_state + s_channels[idx].relay_invert)%2);
   }
   if (s_channels[idx].led_gpio != GPIO_INVALID) {
-    mgos_gpio_write(s_channels[idx].led_gpio, state);
+    mgos_gpio_write(s_channels[idx].led_gpio, (s_channels[idx].relay_state + s_channels[idx].led_invert)%2);
   }
 
   mqtt_publish_stat("channel", "{idx: %d, relay_state: %d}", idx, channel_get(idx));