/* gui.c

   This file is part of the "First" CPU simulator project.

   Copyright (c) 2024 Efthymios Kritikos

   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 <ncurses.h>
#include <string.h>
#include "simdata.h"

int terminal_width;
int terminal_height;

WINDOW *tabs;
WINDOW *general_memdump;

int monochrome;

int get_terminal_size(){
	int new_height,new_width;
	getmaxyx(stdscr,new_height,new_width);
	int changed=(new_width!=terminal_width)||(new_height!=terminal_height);
	terminal_width=new_width;
	terminal_height=new_height;
	return changed;
}

int gui_ncurses_refresh(){
	if(refresh()==ERR)
		return 1;
	if(wrefresh(tabs)==ERR)
		return 1;
	if(wrefresh(general_memdump)==ERR)
		return 1;
	return 0;
}

char *tab_name[]={"Overview","Memory","Internal"};

unsigned int CURRENT_TAB=0;

enum CPU_STATE_t CPU_STATE=SINGLE_STEPPING;
//enum CPU_STATE_t CPU_STATE=STOPPED;

void update_tabs(){
	wattron(tabs,COLOR_PAIR(2));
	for(int i=0;i<terminal_width;i++)
		mvwprintw(tabs,0,i," ");

	int x=2;
	for(unsigned int i=0;i<sizeof(tab_name)/sizeof(tab_name[0]);i++){
		if(i==CURRENT_TAB)
			wattron(tabs,COLOR_PAIR(4));
		else
			wattron(tabs,COLOR_PAIR(5));
		mvwprintw(tabs,0,x," %1d",i);
		x+=2;
		if(i==CURRENT_TAB)
			wattron(tabs,COLOR_PAIR(3));
		else
			wattron(tabs,COLOR_PAIR(2));
		mvwprintw(tabs,0,x," %s ",tab_name[i]);
		x+=strlen(tab_name[i])+2+3;
	}
	switch(CPU_STATE){
		case RUNNING:
			wattron(tabs,COLOR_PAIR(6));
			mvwprintw(tabs,0,terminal_width-13,"[ RUNNING ");
			break;
		case SINGLE_STEPPING:
			wattron(tabs,COLOR_PAIR(7));
			mvwprintw(tabs,0,terminal_width-21,"[ SINGLE-STEPPING ");
			break;
		case STOPPED:
			wattron(tabs,COLOR_PAIR(8));
			mvwprintw(tabs,0,terminal_width-13,"[ STOPPED ");
			break;
	}
	mvwprintw(tabs,0,terminal_width-3,"]");
}

int start_gui(){
	if(!initscr())
		return 1;
	monochrome=( has_colors() == FALSE );
	init_color(8, 700, 700, 700);
	init_color(COLOR_WHITE, 100, 1000, 1000);
	if(!monochrome){
		start_color();
		init_pair(1, COLOR_RED, COLOR_BLACK);

		//tab colors
		init_pair(2, COLOR_BLACK, 8);
		init_pair(3, 8, COLOR_BLACK);
		init_pair(4, COLOR_WHITE, COLOR_BLACK);
		init_pair(5, COLOR_WHITE, 8);
		init_pair(6, COLOR_BLACK,COLOR_GREEN);
		init_pair(7, COLOR_BLACK,COLOR_YELLOW);
		init_pair(8, COLOR_BLACK,COLOR_RED);
	}
	noecho();
	curs_set(0);
	get_terminal_size();
	mvprintw((terminal_height-3)/2+3,terminal_width/2-15,"Initialising the simulator...");
	tabs = newwin(1,terminal_width,0,0);
	update_tabs();
	general_memdump=newwin(terminal_height*0.8,terminal_width/2,4,5);
	if(gui_ncurses_refresh())
		return 1;
	return 0;
}

int gui_error(char *str){
	WINDOW *error_win = newwin(3,40,terminal_height/2-1,terminal_width/2-20);
	box(error_win, 0 , 0);
	if(!monochrome)
		wattron(error_win,COLOR_PAIR(1));
	mvwprintw(error_win,1,1,"%s",str);
	if(wrefresh(error_win)==ERR)
		return 1;
	getch();
	delwin(error_win);
	return 0;

	if(!monochrome)
		wattroff(error_win,COLOR_PAIR(1));
}

int update_general_memdump(struct simdata_t *simdata){
	int width,height;
	getmaxyx(general_memdump,height,width);
	box(general_memdump, 0 , 0);
	mvwprintw(general_memdump,0,terminal_width/4-6,"[ MEMDUMP ]");
	if(width<16){
		mvwprintw(general_memdump,1,1,"too small window");
	}else{
		int n=(width-12)/4; // bytes in each line
		int usable_height=height-3-(width-12)%2;

		uint32_t ADDRESS=(simdata->PC-n*usable_height/2)&0x00FFFFFF;
		for(int h=0;h<usable_height;h++){
			wmove(general_memdump,h+2,2+(width-12)%2);
			wprintw(general_memdump,"%06x  ",ADDRESS);
			uint32_t temp_address=ADDRESS;
			for (int i=0;i<n;i++)
				wprintw(general_memdump,"%02x ",simdata->RAM[temp_address++]);
			for (int i=0;i<n;i++){
				wprintw(general_memdump,"%c",(simdata->RAM[ADDRESS]>=0x20&&simdata->RAM[ADDRESS]<0x7F)?simdata->RAM[ADDRESS]:'.');
				ADDRESS=(ADDRESS+1)&0xFFFFFF;
			}
		}
	}
	return 0;
}

int update_gui(struct simdata_t *simdata){
	clear();
	update_tabs();
	if(update_general_memdump(simdata))
		return 1;
	if(gui_ncurses_refresh())
		return 1;
	return 0;
}

int gui_continue_request(){
	if(getch()==ERR)
		return 1;
	return 0;
}

int end_gui(){
	if(endwin()==ERR)
		return 1;
	return 0;
}