[homeassistant] Native switch entity import and control (#7018)

Co-authored-by: Jesse Hills <3060199+jesserockz@users.noreply.github.com>

esphome/components/homeassistant/switch/homeassistant_switch.cpp

@@ -0,0 +1,59 @@
+#include "homeassistant_switch.h"
+#include "esphome/components/api/api_server.h"
+#include "esphome/core/log.h"
+
+namespace esphome {
+namespace homeassistant {
+
+static const char *const TAG = "homeassistant.switch";
+
+using namespace esphome::switch_;
+
+void HomeassistantSwitch::setup() {
+  api::global_api_server->subscribe_home_assistant_state(this->entity_id_, nullopt, [this](const std::string &state) {
+    auto val = parse_on_off(state.c_str());
+    switch (val) {
+      case PARSE_NONE:
+      case PARSE_TOGGLE:
+        ESP_LOGW(TAG, "Can't convert '%s' to binary state!", state.c_str());
+        break;
+      case PARSE_ON:
+      case PARSE_OFF:
+        bool new_state = val == PARSE_ON;
+        ESP_LOGD(TAG, "'%s': Got state %s", this->entity_id_.c_str(), ONOFF(new_state));
+        this->publish_state(new_state);
+        break;
+    }
+  });
+}
+
+void HomeassistantSwitch::dump_config() {
+  LOG_SWITCH("", "Homeassistant Switch", this);
+  ESP_LOGCONFIG(TAG, "  Entity ID: '%s'", this->entity_id_.c_str());
+}
+
+float HomeassistantSwitch::get_setup_priority() const { return setup_priority::AFTER_CONNECTION; }
+
+void HomeassistantSwitch::write_state(bool state) {
+  if (!api::global_api_server->is_connected()) {
+    ESP_LOGE(TAG, "No clients connected to API server");
+    return;
+  }
+
+  api::HomeassistantServiceResponse resp;
+  if (state) {
+    resp.service = "switch.turn_on";
+  } else {
+    resp.service = "switch.turn_off";
+  }
+
+  api::HomeassistantServiceMap entity_id_kv;
+  entity_id_kv.key = "entity_id";
+  entity_id_kv.value = this->entity_id_;
+  resp.data.push_back(entity_id_kv);
+
+  api::global_api_server->send_homeassistant_service_call(resp);
+}
+
+}  // namespace homeassistant
+}  // namespace esphome