/*#############################################################

Program Name    : ex3_Keypad_KeyHoldIn
Author          : Grant Phillips
Date Modified   : 05/04/2016
Compiler        : ARMmbed
Tested On       : STM32F4-Discovery

Description     : Example program that demonstrates the use of
                  the Keypad class to use when a 4x4 keypad 
                  using a polling method.  
                  Allows a user to enter and exit a menu type
                  application by holding in the '*' key.

                  The output is displayed on a PC using the
                  Serial Wire Viewer (SWV).  See the SWV examples
                  for an explanation of the use of this feature.

Requirements    : * STM32F4-Discovery Board
              
Circuit         : * 4x4 Keypad connected as follows:
                    COL1 (pin1)     -       PE15
                    COL2 (pin2)     -       PE14
                    COL3 (pin3)     -       PE13
                    COL4 (pin4)     -       PE12
                    ROW1 (pin5)     -       PE11
                    ROW2 (pin6)     -       PE10
                    ROW3 (pin7)     -       PE9
                    ROW4 (pin8)     -       PE8

                  * A wire link between PB3 and pin6 of the SWD
                    connector (CN2) as explained in the SWV
                    examples section

##############################################################*/

#include "mbed.h"
#include "Keypad.h"
#include "SWO.h"

Keypad kpad(PE_15, PE_14, PE_13, PE_12, PE_11, PE_10, PE_9, PE_8);
          //col1, col2, col3, col4, row1, row2, row3, row4
SWO_Channel SWO;

int main() {
    char key;
    int released = 1;                           //flag for indicating if a key was released (=1) or not (=0)
    
    uint32_t holdcounter = 0;
    int InMenuFlag = 0;
    int EnterMenuFlag = 0;
       
    SWO.printf("\nHold in * to enter the menu ...");
    
    while(1) {
        key = kpad.ReadKey();                   //read the current key pressed, but don't wait for a key to be pressed
        
        if(key == '\0')                         //if no key is pressed
            released = 1;                       //set the flag when all keys are released
            
        if((key != '\0') && (released == 1)) {  //if a key is pressed AND previous key was released           
            if(key == '*') {                    //if * is pressed
                holdcounter++;                          //increment a counter while the * key is held in
                if(holdcounter >= 200) {                //a nominal value which the counter much reach to indicate the key was held in long enough (+/- 2 sec)
                    holdcounter = 0;                        
                    if(InMenuFlag == 0) {               //if not in the menu ...
                        InMenuFlag = 1;                 //now go into the menu
                        EnterMenuFlag = 1;              //display the menu
                    }
                    else {                              //if in the menu...
                        InMenuFlag = 0;                 //now go out of the menu
                        SWO.printf("\n\n\n\n\n\n\nHold in * to enter the menu ...");
                    }
                }
            }
            else {
                if(InMenuFlag == 1) {                   //if any other key is pressed AND in the menu
                    SWO.printf("%c\n", key);            //print the character for the key pressed
                    switch(key) {
                        case '1':   SWO.printf("You selected Popcorn\n\n");
                                            EnterMenuFlag = 1;
                                            break;
                        case '2':   SWO.printf("You selected Chocolate\n\n");
                                            EnterMenuFlag = 1;
                                            break;
                        case '3':   SWO.printf("You selected Milkshake\n\n");
                                            EnterMenuFlag = 1;
                                            break;
                        case '4':   SWO.printf("You selected Cooldrink\n\n");
                                            EnterMenuFlag = 1;
                                            break;
                        default:    SWO.printf("Incorrect choice!\n\n");
                                            EnterMenuFlag = 1;
                    }
                    released = 0;                       //clear the flag to indicate that key is still pressed
                }
            }
        }
        
        if(EnterMenuFlag == 1) {                //display the menu
            SWO.printf("\n\n\nMENU\n");
            SWO.printf("====\n");
            SWO.printf("1. Popcorn\n");
            SWO.printf("2. Chocolate\n");
            SWO.printf("3. Milkshake\n");
            SWO.printf("4. Cooldrink\n");
            SWO.printf("Make your selection (hold * to exit): ");
            EnterMenuFlag = 0;
        }
    }
}