/*
	VitaShell
	Copyright (C) 2015-2017, TheFloW

	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 3 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, see <http://www.gnu.org/licenses/>.
*/

#include "main.h"
#include "ime_dialog.h"
#include "utils.h"

static int ime_dialog_running = 0;
static int ime_dialog_option = 0;

static const char *ime_initial_text = NULL;
static uint16_t ime_title_utf16[SCE_IME_DIALOG_MAX_TITLE_LENGTH];
static uint16_t ime_initial_text_utf16[SCE_IME_DIALOG_MAX_TEXT_LENGTH];
static uint16_t ime_input_text_utf16[SCE_IME_DIALOG_MAX_TEXT_LENGTH + 1];
static uint8_t ime_input_text_utf8[SCE_IME_DIALOG_MAX_TEXT_LENGTH + 1];

static void utf16_to_utf8(const uint16_t *src, uint8_t *dst) {
	int i;
	for (i = 0; src[i]; i++) {
		if ((src[i] & 0xFF80) == 0) {
			*(dst++) = src[i] & 0xFF;
		} else if((src[i] & 0xF800) == 0) {
			*(dst++) = ((src[i] >> 6) & 0xFF) | 0xC0;
			*(dst++) = (src[i] & 0x3F) | 0x80;
		} else if((src[i] & 0xFC00) == 0xD800 && (src[i+1] & 0xFC00) == 0xDC00) {
			*(dst++) = (((src[i] + 64) >> 8) & 0x3) | 0xF0;
			*(dst++) = (((src[i] >> 2) + 16) & 0x3F) | 0x80;
			*(dst++) = ((src[i] >> 4) & 0x30) | 0x80 | ((src[i+1] << 2) & 0xF);
			*(dst++) = (src[i+1] & 0x3F) | 0x80;
			i += 1;
		} else {
			*(dst++) = ((src[i] >> 12) & 0xF) | 0xE0;
			*(dst++) = ((src[i] >> 6) & 0x3F) | 0x80;
			*(dst++) = (src[i] & 0x3F) | 0x80;
		}
	}

	*dst = '\0';
}

static void utf8_to_utf16(const uint8_t *src, uint16_t *dst) {
	int i;
	for (i = 0; src[i];) {
		if ((src[i] & 0xE0) == 0xE0) {
			*(dst++) = ((src[i] & 0x0F) << 12) | ((src[i+1] & 0x3F) << 6) | (src[i+2] & 0x3F);
			i += 3;
		} else if ((src[i] & 0xC0) == 0xC0) {
			*(dst++) = ((src[i] & 0x1F) << 6) | (src[i+1] & 0x3F);
			i += 2;
		} else {
			*(dst++) = src[i];
			i += 1;
		}
	}

	*dst = '\0';
}

int initImeDialog(const char *title, const char *initial_text, int max_text_length, int type, int option) {
	if (ime_dialog_running)
		return -1;

	ime_initial_text = initial_text;

	// Convert UTF8 to UTF16
	utf8_to_utf16((uint8_t *)title, ime_title_utf16);
	utf8_to_utf16((uint8_t *)initial_text, ime_initial_text_utf16);

	SceImeDialogParam param;
	sceImeDialogParamInit(&param);

	param.supportedLanguages = 0x0001FFFF;
	param.languagesForced = SCE_TRUE;
	param.type = type;
	param.option = option;
	if (option == SCE_IME_OPTION_MULTILINE)
		param.dialogMode = SCE_IME_DIALOG_DIALOG_MODE_WITH_CANCEL;
	param.title = ime_title_utf16;
	param.maxTextLength = max_text_length;
	param.initialText = ime_initial_text_utf16;
	param.inputTextBuffer = ime_input_text_utf16;

	int res = sceImeDialogInit(&param);
	if (res >= 0) {
		ime_dialog_running = 1;
		ime_dialog_option = option;
	}

	return res;
}

int isImeDialogRunning() {
	return ime_dialog_running;	
}

uint16_t *getImeDialogInputTextUTF16() {
	return ime_input_text_utf16;
}

uint8_t *getImeDialogInputTextUTF8() {
	return ime_input_text_utf8;
}

const char *getImeDialogInitialText() {
	return ime_initial_text;
}

int updateImeDialog() {
	if (!ime_dialog_running)
		return IME_DIALOG_RESULT_NONE;

	SceCommonDialogStatus status = sceImeDialogGetStatus();
	if (status == IME_DIALOG_RESULT_FINISHED) {
		SceImeDialogResult result;
		memset(&result, 0, sizeof(SceImeDialogResult));
		sceImeDialogGetResult(&result);

		if ((ime_dialog_option == SCE_IME_OPTION_MULTILINE && result.button == SCE_IME_DIALOG_BUTTON_CLOSE) ||
			(ime_dialog_option != SCE_IME_OPTION_MULTILINE && result.button == SCE_IME_DIALOG_BUTTON_ENTER)) {
			// Convert UTF16 to UTF8
			utf16_to_utf8(ime_input_text_utf16, ime_input_text_utf8);
		} else {
			status = IME_DIALOG_RESULT_CANCELED;
		}

		sceImeDialogTerm();

		ime_dialog_running = 0;
	}

	return status;
}