From 644aec791ee5b6d84142033298a277f42a393a93 Mon Sep 17 00:00:00 2001
From: Otto Winter <otto@otto-winter.com>
Date: Sun, 20 Oct 2019 18:10:14 +0200
Subject: [PATCH] Add GPIO Switch interlock wait time (#777)

* Add interlock wait time to gpio switch

Fixes https://github.com/esphome/issues/issues/753

* Format

* Fix
---
 esphome/components/gpio/switch/__init__.py     |  3 +++
 esphome/components/gpio/switch/gpio_switch.cpp | 18 +++++++++++++++++-
 esphome/components/gpio/switch/gpio_switch.h   |  2 ++
 3 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/esphome/components/gpio/switch/__init__.py b/esphome/components/gpio/switch/__init__.py
index 7b383cb8a9..f75bc71009 100644
--- a/esphome/components/gpio/switch/__init__.py
+++ b/esphome/components/gpio/switch/__init__.py
@@ -15,12 +15,14 @@ RESTORE_MODES = {
     'ALWAYS_ON': GPIOSwitchRestoreMode.GPIO_SWITCH_ALWAYS_ON,
 }
 
+CONF_INTERLOCK_WAIT_TIME = 'interlock_wait_time'
 CONFIG_SCHEMA = switch.SWITCH_SCHEMA.extend({
     cv.GenerateID(): cv.declare_id(GPIOSwitch),
     cv.Required(CONF_PIN): pins.gpio_output_pin_schema,
     cv.Optional(CONF_RESTORE_MODE, default='RESTORE_DEFAULT_OFF'):
         cv.enum(RESTORE_MODES, upper=True, space='_'),
     cv.Optional(CONF_INTERLOCK): cv.ensure_list(cv.use_id(switch.Switch)),
+    cv.Optional(CONF_INTERLOCK_WAIT_TIME, default='0ms'): cv.positive_time_period_milliseconds,
 }).extend(cv.COMPONENT_SCHEMA)
 
 
@@ -40,3 +42,4 @@ def to_code(config):
             lock = yield cg.get_variable(it)
             interlock.append(lock)
         cg.add(var.set_interlock(interlock))
+        cg.add(var.set_interlock_wait_time(config[CONF_INTERLOCK_WAIT_TIME]))
diff --git a/esphome/components/gpio/switch/gpio_switch.cpp b/esphome/components/gpio/switch/gpio_switch.cpp
index d22a74847e..d87e5a61e6 100644
--- a/esphome/components/gpio/switch/gpio_switch.cpp
+++ b/esphome/components/gpio/switch/gpio_switch.cpp
@@ -69,13 +69,29 @@ void GPIOSwitch::dump_config() {
 void GPIOSwitch::write_state(bool state) {
   if (state != this->inverted_) {
     // Turning ON, check interlocking
+
+    bool found = false;
     for (auto *lock : this->interlock_) {
       if (lock == this)
         continue;
 
-      if (lock->state)
+      if (lock->state) {
         lock->turn_off();
+        found = true;
+      }
     }
+    if (found && this->interlock_wait_time_ != 0) {
+      this->set_timeout("interlock", this->interlock_wait_time_, [this, state] {
+        // Don't write directly, call the function again
+        // (some other switch may have changed state while we were waiting)
+        this->write_state(state);
+      });
+      return;
+    }
+  } else if (this->interlock_wait_time_ != 0) {
+    // If we are switched off during the interlock wait time, cancel any pending
+    // re-activations
+    this->cancel_timeout("interlock");
   }
 
   this->pin_->digital_write(state);
diff --git a/esphome/components/gpio/switch/gpio_switch.h b/esphome/components/gpio/switch/gpio_switch.h
index ceace477b2..dc0dd9bc95 100644
--- a/esphome/components/gpio/switch/gpio_switch.h
+++ b/esphome/components/gpio/switch/gpio_switch.h
@@ -26,6 +26,7 @@ class GPIOSwitch : public switch_::Switch, public Component {
   void setup() override;
   void dump_config() override;
   void set_interlock(const std::vector<Switch *> &interlock);
+  void set_interlock_wait_time(uint32_t interlock_wait_time) { interlock_wait_time_ = interlock_wait_time; }
 
  protected:
   void write_state(bool state) override;
@@ -33,6 +34,7 @@ class GPIOSwitch : public switch_::Switch, public Component {
   GPIOPin *pin_;
   GPIOSwitchRestoreMode restore_mode_{GPIO_SWITCH_RESTORE_DEFAULT_OFF};
   std::vector<Switch *> interlock_;
+  uint32_t interlock_wait_time_{0};
 };
 
 }  // namespace gpio