/* This example shows a simple Intuition program that works with
 * Release 2 (V36) and later versions of the Amiga operating system.
 */

/* easyintuition37.c -- Simple Intuition program for V37   */
/* (Release 2) and later versions of the operating system. */
/* Compiled with Lattice C v5.04: lc -L easyintuition37.c  */

#include <exec/types.h>             /* The Amiga data types file.         */
#include <intuition/intuition.h>    /* Intuition data strucutres, etc.    */
#include <graphics/displayinfo.h>   /* Release 2 Amiga display mode ID's  */
#include <libraries/dos.h>          /* Official return codes defined here */

#include <clib/exec_protos.h>       /* Exec function prototypes           */
#include <clib/intuition_protos.h>  /* Intuition function prototypes      */

/* Force use of new variable names to help prevent errors  */
#define INTUI_V36_NAMES_ONLY

#ifdef LATTICE                      /* Disable Ctrl-C handling in SAS/C   */
int CXBRK(void)  {return(0);}
void chkabort(void) {return;}
#endif

/* Use lowest non-obsolete version that supplies the functions needed. */
#define INTUITION_REV 37

/* Declare the prototypes of our own functions.  Prototypes for system */
/* functions are declared in the header files in the clib directory.   */
VOID cleanExit( struct Screen *, struct Window *, LONG );
BOOL handleIDCMP( struct Window *);

struct Library *IntuitionBase = NULL;

/* Position and sizes for our window */
#define WIN_LEFTEDGE   20
#define WIN_TOPEDGE    20
#define WIN_WIDTH     400
#define WIN_MINWIDTH   80
#define WIN_HEIGHT    150
#define WIN_MINHEIGHT  20


VOID main(int argc, char *argv[])
{
    /* Declare variables here */
    ULONG signalmask, winsignal, signals;
    BOOL done = FALSE;
    UWORD pens[]={~0};

    struct Screen *screen1 = NULL;
    struct Window *window1 = NULL;

    /* Open the Intuition Library */
    IntuitionBase = OpenLibrary( "intuition.library",INTUITION_REV );
    if (IntuitionBase == NULL)
        cleanExit(screen1, window1, RETURN_WARN);

    /* Open any other required libraries and make */
    /* any assignments that were postponed above  */

    /* Open the screen */
    screen1 = OpenScreenTags(NULL,
                             SA_Pens,  (ULONG)pens,
                             SA_DisplayID, HIRES_KEY,
                             SA_Depth, 2,
                             SA_Title, (ULONG)"Our Screen",
                             TAG_DONE);

    if (screen1 == NULL)
        cleanExit(screen1, window1, RETURN_WARN);

    /* ... and open the window */
    window1 = OpenWindowTags(NULL,
                             /* Specify window dimensions and limits */
                             WA_Left,         WIN_LEFTEDGE,
                             WA_Top,          WIN_TOPEDGE,
                             WA_Width,        WIN_WIDTH,
                             WA_Height,       WIN_HEIGHT,
                             WA_MinWidth,     WIN_MINWIDTH,
                             WA_MinHeight,    WIN_MINHEIGHT,
                             WA_MaxWidth,     ~0,
                             WA_MaxHeight,    ~0,
                             /* Specify the system gadgets we want */
                             WA_CloseGadget,  TRUE,
                             WA_SizeGadget,   TRUE,
                             WA_DepthGadget,  TRUE,
                             WA_DragBar,      TRUE,
                             /* Specify other attributes           */
                             WA_Activate,     TRUE,
                             WA_NoCareRefresh,TRUE,

                             /* Specify the events we want to know about */
                             WA_IDCMP,        IDCMP_CLOSEWINDOW,

                             /* Attach the window to the open screen ...*/
                             WA_CustomScreen, screen1,
                             WA_Title,        "EasyWindow",
                             WA_ScreenTitle,  "Our Screen - EasyWindow is Active",
                             TAG_DONE);
    if (window1 == NULL)
        cleanExit(screen1, window1, RETURN_WARN);

    /* Set up the signals for the events we want to hear about ...   */
    winsignal = 1L << window1->UserPort->mp_SigBit;  /* window IDCMP */
    signalmask = winsignal;   /* we are only waiting on IDCMP events */

    /* Here's the main input event loop where we wait for events.    */
    /* We have asked Intuition to send us CLOSEWINDOW IDCMP events   */
    /* Exec will wake us if any event we are waiting for occurs.     */
    while( !done )
    {
        signals = Wait(signalmask);

        /* An event occurred - now act on the signal(s) we received.*/
        /* We were only waiting on one signal (winsignal) in our    */
        /* signalmask, so we actually know we received winsignal.   */
        if(signals & winsignal)
            done = handleIDCMP(window1);    /* done if close gadget */
    }
    cleanExit(screen1, window1, RETURN_OK); /* Exit the program     */
}

BOOL handleIDCMP( struct Window *win )
{
    BOOL done = FALSE;
    struct IntuiMessage *message = NULL;
    ULONG class;

    /* Examine pending messages */
    while( message = (struct IntuiMessage *)GetMsg(win->UserPort) )
    {
        class = message->Class;  /* get all data we need from message */

        /* When we're through with a message, reply */
        ReplyMsg( (struct Message *)message);

        /* See what events occurred */
        switch( class )
        {
            case IDCMP_CLOSEWINDOW:
                done = TRUE;
                break;
            default:
                break;
        }
    }
    return(done);
}

VOID cleanExit( struct Screen *scrn, struct Window *wind, LONG returnValue )
{
    /* Close things in the reverse order of opening */
    if (wind) CloseWindow( wind );      /* Close window if opened */
    if (scrn) CloseScreen( scrn );      /* Close screen if opened */

    /* Close the library, and then exit */
    if (IntuitionBase) CloseLibrary( IntuitionBase );
    exit(returnValue);
}