Adding arduino code

.gitignore

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+secrets*

arduino/Houseplant/Houseplant.ino

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+// WiFi Module
+#include <ESP8266WiFi.h>
+#include <ESP8266HTTPClient.h>
+#include <WiFiClientSecureBearSSL.h>
+
+// Constants and variables
+const int sensorPin = A0;
+const unsigned long interval = 3600000; // One hour
+//const unsigned long interval = 21600000; // Six hours
+unsigned long lastUpdate = millis() - interval;
+int reading;
+HTTPClient https;
+
+// WiFi & Connectivity Settings
+#include "secrets.h"
+/*
+  secrets.h contents:
+    const char* wifi_ssid = "";
+    const char* wifi_pass = "";
+    const char* gcp_app_secret = "";
+*/
+
+void setup() {
+  Serial.begin(115200);
+  setup_wifi();
+}
+
+void setup_wifi() {
+  delay(10);
+  Serial.print("WiFi connecting to ");
+  Serial.println(wifi_ssid);
+
+  WiFi.begin(wifi_ssid, wifi_pass);
+
+  while (WiFi.status() != WL_CONNECTED) {
+    delay(500);
+    Serial.print(".");
+  }
+
+  Serial.println("WiFi connected");
+  Serial.print("IP address: ");
+  Serial.println(WiFi.localIP());
+}
+
+void loop() {
+  if (millis() - lastUpdate >= interval) {
+    lastUpdate = millis();
+
+    Serial.print("Reading: ");
+    reading = analogRead(sensorPin);
+    Serial.println(reading);
+
+    std::unique_ptr<BearSSL::WiFiClientSecure>client(new BearSSL::WiFiClientSecure);
+    client->setInsecure();
+
+    // Publish to GCP app
+    if (https.begin(*client, "https://houseplantcloud.appspot.com/newreading?s=" + String(gcp_app_secret) + "&v=" + String(reading))) {
+      int httpCode = https.GET();
+
+      if (httpCode > 0) {
+        if (httpCode == HTTP_CODE_OK || httpCode == HTTP_CODE_MOVED_PERMANENTLY) {
+          String payload = https.getString();
+          Serial.print("Response from server: ");
+          Serial.println(payload);
+        }
+      } else {
+        Serial.printf("Server connection failed: %s\n", https.errorToString(httpCode).c_str());
+      }
+    } else {
+      Serial.println("Server connection failed");
+    }
+
+    // Publish to glitch app
+    if (https.begin(*client, "https://jasonsplant.glitch.me/newreading?s=" + String(gcp_app_secret) + "&v=" + String(reading))) {
+      int httpCode = https.GET();
+
+      if (httpCode > 0) {
+        if (httpCode == HTTP_CODE_OK || httpCode == HTTP_CODE_MOVED_PERMANENTLY) {
+          String payload = https.getString();
+          Serial.print("Response from server: ");
+          Serial.println(payload);
+        }
+      } else {
+        Serial.printf("Server connection failed: %s\n", https.errorToString(httpCode).c_str());
+      }
+    } else {
+      Serial.println("Server connection failed");
+    }
+  }
+}