/*
Program to find various properties of triangles
Original layout by Paul Davey, 2007
Debugging and restructure by Jonathan Love, 2007

Notes:
- C99 Compatible:
	- all 'for' loops replaced with 'while' (Jonathan)
	- Standard variable types - no strings or files (Paul)

- Used Defines for boolean replacement. (Jonathan)
- All vars and functions renamed appropriately according to their return - e.g. iCalcPerimeter returns and integer, fCalcArea returns float (Jonathan)
- System independent - no system calls (Paul)
- Adjusted call to fCalcArea to fix iCalcPerimeter call (Jonathan)
- Algorithms implemented, except isRightAngled (Paul)
- Menu System (Paul)
- Functional Program (Jonathan)

THIS PROGRAM WILL COMPILE WITH GCC!
*/
#include <stdio.h>
#include <stdlib.h>
#include <math.h>

//Constants and Defines
#define TRUE 1;
#define FALSE 0;

void fnClear()
{
		//Clear the screen - no library dependence, but puts cursor at screen bottom
		int iCounter = 0;
		while (iCounter < 25)	//Assume 25 is screen height
		{
			printf("\n");
			iCounter++;
		}
}


int iCalcPerimeter(int iSides[])
{
    //Calculate Perimeter
	int iPerimeter = 0;
	int iCounter = 0;
    while (iCounter < 3)
	{
		iPerimeter += iSides[iCounter];
		iCounter++;
    }
    return iPerimeter;
}

int isRightAngled(int iSides[])
{
	//Enter isRightAngled algorithm here
	return FALSE;
}

float fCalcArea(int iSides[])
{
	//Calculate Area
	float fS = iCalcPerimeter(iSides)/2;
    return sqrt(fS*(fS - iSides[0])*(fS - iSides[1])*(fS - iSides[2]));
}
 
       

int main(int argc, char *argv[])
{
	//Integers
	int iSides[3];
	int iResponse;

	//Booleans - which are actually integers
	int isExit		= FALSE;
	int isInputDone	= FALSE;
	 
	//Chars and Char Pointers (Strings)
	char cYesNo;

	 while (!isExit)
		{
			//Main Menu
			
			isInputDone = FALSE;		//Restore false status
			iResponse = 0;
			
			//Get three Sides
			printf("Please enter the lengths of the three sides of a triangle:");
			printf("\nSide 1: ");
			scanf("%d",&iSides[0]);
			printf("Side 2: ");
			scanf("%d",&iSides[1]);
			printf("Side 3: ");
			scanf("%d",&iSides[2]);
			
			//Do until input done = true (IE new triangle)
			while (!isInputDone)
			{
				fnClear();
				//Ask for a menu option. Usually clear screen here
				printf("1: Find the perimeter of the triangle.\n");
				printf("2: Find if the triangle is right angled or not.\n");
				printf("3: Find the area of the triangle\n");
				printf("4: Enter a new triangle\n");
				printf("5: Quit Program\n\n");
				printf("Please enter the number of the option you want: ");
				
				//Get input response
				scanf("%d", &iResponse);
				printf("\n");
				switch (iResponse)
				{
						case 1: 
								//Find the perimeter
								printf("The perimeter is:%d\n", iCalcPerimeter(iSides));
								break;
						case 2: 
								//Find whether triangle is right-angled
								isRightAngled(iSides);
								printf("Not Implemented Yet\n");
								break;
						case 3: 
								//Determine triangle area
								printf("The area is:%f\n",fCalcArea(iSides));
								break;
						case 4:
								//Get new triangle
								isInputDone	= TRUE;
								break;
						case 5:
								//Input is done and we want to exit
								isInputDone = TRUE;
								isExit = TRUE;
								break;
				         default: 
								printf("Please enter a number from the menu:");
								break;
				}
			
				printf("\n\n");		//Print some newlines
			} 
		}
		
	return 0;
}