/*
 * synergy -- mouse and keyboard sharing utility
 * Copyright (C) 2016 Symless Ltd.
 * 
 * This package is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * found in the file LICENSE that should have accompanied this file.
 * 
 * This package 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, see <http://www.gnu.org/licenses/>.
 */

#include "platform/IKeyResource.h"

#include <Carbon/Carbon.h>

//
// OSXKeyState::KeyResource
//

KeyID
IKeyResource::getKeyID(UInt8 c)
{
	if (c == 0) {
		return kKeyNone;
	}
	else if (c >= 32 && c < 127) {
		// ASCII
		return static_cast<KeyID>(c);
	}
	else {
		// handle special keys
		switch (c) {
		case 0x01:
			return kKeyHome;

		case 0x02:
			return kKeyKP_Enter;

		case 0x03:
			return kKeyKP_Enter;

		case 0x04:
			return kKeyEnd;

		case 0x05:
			return kKeyHelp;

		case 0x08:
			return kKeyBackSpace;

		case 0x09:
			return kKeyTab;

		case 0x0b:
			return kKeyPageUp;

		case 0x0c:
			return kKeyPageDown;

		case 0x0d:
			return kKeyReturn;

		case 0x10:
			// OS X maps all the function keys (F1, etc) to this one key.
			// we can't determine the right key here so we have to do it
			// some other way.
			return kKeyNone;

		case 0x1b:
			return kKeyEscape;

		case 0x1c:
			return kKeyLeft;

		case 0x1d:
			return kKeyRight;

		case 0x1e:
			return kKeyUp;

		case 0x1f:
			return kKeyDown;

		case 0x7f:
			return kKeyDelete;

		case 0x06:
		case 0x07:
		case 0x0a:
		case 0x0e:
		case 0x0f:
		case 0x11:
		case 0x12:
		case 0x13:
		case 0x14:
		case 0x15:
		case 0x16:
		case 0x17:
		case 0x18:
		case 0x19:
		case 0x1a:
			// discard other control characters
			return kKeyNone;

		default:
			// not special or unknown
			break;
		}

		// create string with character
		char str[2];
		str[0] = static_cast<char>(c);
		str[1] = 0;

		// get current keyboard script
		TISInputSourceRef isref = TISCopyCurrentKeyboardInputSource();
		CFArrayRef langs = (CFArrayRef) TISGetInputSourceProperty(isref, kTISPropertyInputSourceLanguages);
		CFStringEncoding encoding = CFStringConvertIANACharSetNameToEncoding(
										(CFStringRef)CFArrayGetValueAtIndex(langs, 0));
		// convert to unicode
		CFStringRef cfString =
			CFStringCreateWithCStringNoCopy(
				kCFAllocatorDefault, str, encoding, kCFAllocatorNull);

		// sometimes CFStringCreate...() returns NULL (e.g. Apple Korean
		// encoding with char value 214).  if it did then make no key,
		// otherwise CFStringCreateMutableCopy() will crash.
		if (cfString == NULL) {
			return kKeyNone; 
		}

		// convert to precomposed
		CFMutableStringRef mcfString =
			CFStringCreateMutableCopy(kCFAllocatorDefault, 0, cfString);
		CFRelease(cfString);
		CFStringNormalize(mcfString, kCFStringNormalizationFormC);

		// check result
		int unicodeLength = CFStringGetLength(mcfString);
		if (unicodeLength == 0) {
			CFRelease(mcfString);
			return kKeyNone;
		}
		if (unicodeLength > 1) {
			// FIXME -- more than one character, we should handle this
			CFRelease(mcfString);
			return kKeyNone;
		}

		// get unicode character
		UniChar uc = CFStringGetCharacterAtIndex(mcfString, 0);
		CFRelease(mcfString);

		// convert to KeyID
		return static_cast<KeyID>(uc);
	}
}

KeyID
IKeyResource::unicharToKeyID(UniChar c)
{
	switch (c) {
	case 3:
		return kKeyKP_Enter;

	case 8:
		return kKeyBackSpace;

	case 9:
		return kKeyTab;

	case 13:
		return kKeyReturn;

	case 27:
		return kKeyEscape;

	case 127:
		return kKeyDelete;

	default:
		if (c < 32) {
			return kKeyNone;
		}
		return static_cast<KeyID>(c);
	}
}