From d528ba902a82ec1a498614cb93126e2d12fa2544 Mon Sep 17 00:00:00 2001
From: Gerardo Marx <gmarx_cc@itmorelia.edu.mx>
Date: Mon, 20 Apr 2020 05:09:12 +0000
Subject: [PATCH] OOP for LED class OK

---
 LED.cpp  | 57 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 LED.h    | 25 +++++++++++++++++++++++++
 main.cpp | 33 ++++++++++++++++++++++++++++++++
 3 files changed, 115 insertions(+)
 create mode 100644 LED.cpp
 create mode 100644 LED.h
 create mode 100644 main.cpp

diff --git a/LED.cpp b/LED.cpp
new file mode 100644
index 0000000..3d3078f
--- /dev/null
+++ b/LED.cpp
@@ -0,0 +1,57 @@
+/*led.cpp*/
+#include"LED.h"
+#include<iostream>
+#include<fstream>
+#include<string>
+#include<sstream>
+
+#define LED_PATH "/sys/class/leds/beaglebone:green:usr"
+
+LED::LED(int number){
+  this->number = number;
+  std::ostringstream s;
+  s << LED_PATH << number; // LED number to the Path
+  path = std::string(s.str()); // convert to string
+}
+
+void LED::writeLED(std::string filename, std::string value){
+  std::ofstream fs;
+  fs.open((path + filename).c_str());
+  fs << value;
+  fs.close();
+}
+
+void LED::removeTrigger(){
+  writeLED("/trigger", "none");
+}
+
+void LED::turnOn(){
+  std::cout << "Turning LED" << number << "on" << std::endl;
+  removeTrigger();
+  writeLED("/brightness", "1");
+}
+
+void LED::turnOff(){
+  std::cout << "Turning LED" << number << "off" << std::endl;
+  removeTrigger();
+  writeLED("/brightness", "0");
+}
+
+void LED::flash(std::string delayms ="50"){
+  std::cout << "Making LED" << number << "flash" << std::endl;
+  writeLED("/trigger", "timer");
+  writeLED("/delay_on", delayms);
+  writeLED("/delay_off", delayms);
+}
+
+void LED::outputState(){
+  std::ifstream fs;
+  fs.open((path + "/trigger").c_str());
+  std::string line;
+  while(getline(fs,line)) std::cout << line <<std::endl;
+  fs.close();
+}
+
+LED::~LED(){
+  std::cout << "!!Destroying the LED with path: " << path << std::endl;
+}
diff --git a/LED.h b/LED.h
new file mode 100644
index 0000000..006744b
--- /dev/null
+++ b/LED.h
@@ -0,0 +1,25 @@
+/*led.h
+ Gerardo Marx April/19/2020*/
+#ifndef LED_H
+#define LED_H
+#include<iostream>
+#include<fstream>
+#include<string>
+#include<sstream>
+
+class LED{
+private:
+  std::string path;
+  int number;
+  virtual void writeLED(std::string filename, std::string value);
+  virtual void removeTrigger();
+public:
+  LED(int number);
+  virtual void turnOn();
+  virtual void turnOff();
+  virtual void flash(std::string delayms);
+  virtual void outputState();
+  virtual ~LED();
+};
+
+#endif
diff --git a/main.cpp b/main.cpp
new file mode 100644
index 0000000..1446e57
--- /dev/null
+++ b/main.cpp
@@ -0,0 +1,33 @@
+/*OOP in C++ example for LEDs
+ Gerardo Marx April/20/2020
+g++ main.cpp -o main LED.cpp*/
+#include<string>
+#include"LED.h"
+using namespace std;
+
+
+int main(int argc, char* argv[]){
+  if(argc!=2){
+    cout << "The usage is main <command>" << endl;
+    cout << "<command> is on, off flash or status" << endl;
+    cout << "e.g. main on" << endl;
+    return 2;
+  }
+  cout << "Starting program ..." << endl;
+  string cmd(argv[1]);
+  LED leds[4] = {LED(0), LED(1), LED(2), LED(3)};
+  for(int i=0; i<=3; i++){
+    if(cmd=="on")
+      leds[i].turnOn();
+    else if(cmd=="off")
+      leds[i].turnOff();
+    else if(cmd=="flash")
+      leds[i].flash("100");
+    else if(cmd=="status")
+      leds[i].outputState();
+    else
+      cout << "invalid command, please type main" << endl;
+  }
+  cout << "Program done, Thanks." << endl;
+  return 0;
+}