pendulum68k/pendDialog.c

#include "pendDialog.h"
#include <errno.h>
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "common.h"

#define DLOG_PREFS 128
#define DLOG_ABOUT 129

#define PREFS_EDIT_START 3
#define PREFS_EDIT_END 7

enum {
	PREFS_THETA=0,
	PREFS_DTHETA,
	PREFS_MU,
	PREFS_LEN,
	PREFS_GRAV
};

extern Boolean forceRedraw;

static Boolean valid_input(double *n, int no) {
	if( *n == HUGE_VAL ||
		*n == -HUGE_VAL ||
		/*isnan(*n) ||*/		/* Cannot detect NANs */
		(*n == 0.0 && errno == ERANGE)) {
		return false;
	}
	
	switch(no) {
	case PREFS_THETA: {
		*n = fmod(*n, 2*M_PI);
		if(*n > M_PI) *n -= 2*M_PI;
	} return true;
	
	case PREFS_LEN:
	case PREFS_GRAV:
		if(*n == 0.0) return false;
		return true;
	}
	
	return true;
}

static Boolean parse_pi(char *str) {
	return ((tolower(str[0]) == 'p') &&
			(tolower(str[1]) == 'i') &&
			(str[2] == '\0'));
}

static pascal Boolean aboutFilter(DialogPtr theDialog,
								  EventRecord *theEvent,
								  int *itemHit) {
	int 		windowCode;
	WindowPtr 	theWindow;
	
	if(theEvent->what != mouseDown)
		return false;
	windowCode = FindWindow(theEvent->where, &theWindow);
	if(windowCode != inContent || theWindow != theDialog)
		return false;
	
	return true;
}

void DialogAbout() {
	int itemHit;
	DialogPtr dlog = GetNewDialog(DLOG_ABOUT, NULL, (WindowPtr) -1L);
	ModalDialog(&aboutFilter, &itemHit);
	DisposDialog(dlog);
	forceRedraw = true;
}

void DialogPrefs(struct dialog_prefs_t *p) {
	union prefs_choose {
		struct dialog_prefs_t	*rec;
		double					*arr;	/* Size 5 */
	};

	union prefs_choose args;
	double tmpargs[5];
	StringPtr dblText;
	int itemHit, itemno;
	Boolean valid_settings = false;
	DialogPtr dlog;
	
	dblText = (StringPtr) NewPtr(sizeof(Str255));
	if(!dblText) return;
	
	dlog = GetNewDialog(DLOG_PREFS, NULL, (WindowPtr) -1L);
	if(!dlog) goto err_dlog;
	args.rec = p;
	
	/* Convert p's fields to EditText fields */	
	for(itemno = PREFS_EDIT_START; itemno <= PREFS_EDIT_END; ++itemno) {
		int arrval = itemno - PREFS_EDIT_START;
		int itemType;
		ControlHandle itemHandle;
		Rect itemBox;
		
		PLEN(dblText) = sprintf((char *) PSTR(dblText), "%.9g", args.arr[arrval]);
		GetDItem(dlog, itemno, &itemType, &itemHandle, &itemBox);
		SetIText(itemHandle, dblText);
	}
	
	while(!valid_settings) {
		ModalDialog(NULL, &itemHit);
		if(itemHit == cancel) break;
		
		valid_settings = true;
		for(itemno = PREFS_EDIT_START; itemno <= PREFS_EDIT_END; ++itemno) {
			int arrval = itemno - PREFS_EDIT_START;
			int itemType;
			ControlHandle itemHandle;
			Rect itemBox;
			char *endpos;
			
			/* Convert EditText fields to p fields */
			GetDItem(dlog, itemno, &itemType, &itemHandle, &itemBox);
			GetIText(itemHandle, dblText);
			
			/* If a field was left empty */
			if(PLEN(dblText) == 0) {
				valid_settings = false;
				break;
			}
			
			/* Convert to Cstring */
			if(PLEN(dblText) == 255)
				PSTR(dblText)[255] = '\0';
			else
				PSTR(dblText)[PLEN(dblText)] = '\0';
			
			/* Convert to double */
			tmpargs[arrval] = strtod((char *) PSTR(dblText), &endpos);
			if(endpos == (char *) PSTR(dblText)) {
				/* Input: "pi" */
				if(parse_pi(endpos)) {
					tmpargs[arrval] = M_PI;
				} else {
					valid_settings = false;
					break;
				}
			} else if(*endpos != '\0') {
				/* Input: "xx.xxpi" */
				if(parse_pi(endpos)) {
					tmpargs[arrval] *= M_PI;
				} else {
					valid_settings = false;
					break;
				}
			}
					
			/* Modifies / Verifies input */
			if(!valid_input(&tmpargs[arrval], arrval)) {
				valid_settings = false;
				break;
			}
		}
		
		/* Error condition */
		if(!valid_settings) {
			SelIText(dlog, itemno, 0, 32767);
			SysBeep(0);
		}
	}
	
	if(itemHit == ok)
		memcpy(p, tmpargs, sizeof(tmpargs));
	DisposDialog(dlog);
	
err_dlog:
	DisposPtr(dblText);
	forceRedraw = true;
}