/** \file helphelper.c
 * use OSX Help system
 */

/*  XTrkCad - Model Railroad CAD
 *  Copyright (C) 2015 Martin Fischer
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#import <CoreFoundation/CoreFoundation.h>
#import <Carbon/Carbon.h>

#include <stdio.h>
#include <stdlib.h>
#include <dirent.h>
#include <sys/time.h>
#include <signal.h>
#include <unistd.h>
#include <string.h>
#include <ctype.h>
#include <assert.h>
#include <errno.h>
#include <fcntl.h>

#include <stdint.h>

#define HELPCOMMANDPIPE "/tmp/helppipe"
#define EXITCOMMAND "##exit##"


OSStatus MyGoToHelpPage (CFStringRef pagePath, CFStringRef anchorName)
{
	CFBundleRef myApplicationBundle = NULL;
	CFStringRef myBookName = NULL;
	OSStatus err = noErr;
	printf("HelpHelper: Started to look for help\n");

	myApplicationBundle = CFBundleGetMainBundle();
	if (myApplicationBundle == NULL) {
		printf("HelpHelper: Error - No Application Bundle\n");
		err = fnfErr;
		return err;
	}
	printf("HelpHelper: Application Bundle Found\n");

	myBookName = CFBundleGetValueForInfoDictionaryKey(
	                     myApplicationBundle,
	                     CFSTR("CFBundleHelpBookName"));
	if (myBookName == NULL) {
		myBookName = CFStringCreateWithCString(NULL, "XTrackCAD Help",
		                                       kCFStringEncodingMacRoman);
		printf("HelpHelper: Defaulting to 'XTrackCAD Help'\n" );
		err = fnfErr;
		return err;
	}
	printf("HelpHelper: BookName dictionary name %s found\n",
	       CFStringGetCStringPtr(myBookName, kCFStringEncodingMacRoman));

	if (CFGetTypeID(myBookName) != CFStringGetTypeID()) {
		printf("HelpHelper: Error - BookName is not a string\n" );
		err = paramErr;
	}

	if (err == noErr) {
		err = AHGotoPage (myBookName, pagePath, anchorName);
		if (err != noErr) {
			printf("HelpHelper: Error in AHGoToPage('%s','%s')\n",
			       CFStringGetCStringPtr(myBookName, kCFStringEncodingMacRoman),
			       CFStringGetCStringPtr(pagePath, kCFStringEncodingMacRoman));
		}
	}

	return err;

};

int displayHelp(char* name)
{
	CFStringRef str = CFStringCreateWithCString(NULL,name,
	                  kCFStringEncodingMacRoman);
	OSStatus err = MyGoToHelpPage(str, NULL);
	if (err != noErr) { printf("HelpHelper: MyGoToHelpPage had error %d\n", err); }
	return err;

};

int
main( int argc, char **argv )
{
	int handleOfPipe = 0;
	char buffer[ 100 ];
	char issue[ 100 ];

	int len;
	int finished = 0;
	int numBytes = 0;
	int numBytes2 = 0;

	printf( "HelpHelper: starting!\n" );

	handleOfPipe = open( HELPCOMMANDPIPE, O_RDONLY );
	if( handleOfPipe ) {
		printf( "HelpHelper: opened pipe for reading\n" );
		while( !finished ) {
			printf( "HelpHelper: reading from pipe...\n" );
			numBytes = read( handleOfPipe, &len, sizeof( int ));

			if( numBytes > 0 ) {
				printf( "HelpHelper: read %d bytes\n", numBytes );
			}
			if( numBytes == sizeof(int)) {
				printf( "HelpHelper: Expecting %d bytes\n", len );
				numBytes2 = read( handleOfPipe, buffer, len + 1 );
				buffer[numBytes2] = '\0';
				if (numBytes2 > 0) {
					printf( "HelpHelper: Display help on: %s\n", buffer );
				}

				if( !strcmp(buffer, EXITCOMMAND )) {
					finished = 1;
				} else {
					if (displayHelp(buffer) != 0) {
						printf( "HelpHelper: Error\n");
					}
				}
			}
			if( numBytes <= 0 ) {
				printf( "HelpHelper: exiting on pipe error\n" );
				exit( 1 );
			}
		}
	} else {
		printf( "HelpHelper: Could not open pipe for reading\n" );
	}

	printf( "HelpHelper: exiting!" );

	exit( 0 );
};