keyboard.c

#include <SDL/SDL.h>
#include "font.h"

#define NUM_ROWS 6
#define NUM_KEYS 18

//#ifdef RS97

#define KEY_UP SDLK_UP
#define KEY_DOWN SDLK_DOWN
#define KEY_LEFT SDLK_LEFT
#define KEY_RIGHT SDLK_RIGHT
#define KEY_ENTER SDLK_LCTRL // A
#define KEY_TOGGLE SDLK_LALT // B
#define KEY_BACKSPACE SDLK_BACKSPACE // R
#define KEY_SHIFT SDLK_TAB // L
#define KEY_LOCATION SDLK_LSHIFT // Y
#define KEY_ACTIVATE SDLK_SPACE // X
#define KEY_QUIT SDLK_ESCAPE // SELECT
#define KEY_HELP SDLK_RETURN // START

/*#else

#define KEY_UP SDLK_UP
#define KEY_DOWN SDLK_DOWN
#define KEY_LEFT SDLK_LEFT
#define KEY_RIGHT SDLK_RIGHT
#define KEY_ENTER SDLK_RETURN
#define KEY_TOGGLE SDLK_SPACE
#define KEY_BACKSPACE SDLK_b
#define KEY_SHIFT SDLK_s
#define KEY_LOCATION SDLK_l
#define KEY_ACTIVATE SDLK_BACKQUOTE

#endif*/

#define KMOD_SYNTHETIC (1 << 13)

static int row_length[NUM_ROWS] = {13, 17, 17, 15, 14, 8};

static SDLKey keys[2][NUM_ROWS][NUM_KEYS] = {
	{
		{SDLK_ESCAPE, SDLK_F1, SDLK_F2, SDLK_F3, SDLK_F4, SDLK_F5, SDLK_F6, SDLK_F8, SDLK_F9, SDLK_F10, SDLK_F11, SDLK_F12},
		{SDLK_BACKQUOTE, SDLK_1, SDLK_2, SDLK_3, SDLK_4, SDLK_5, SDLK_6, SDLK_7, SDLK_8, SDLK_9, SDLK_0, SDLK_MINUS, SDLK_EQUALS, SDLK_BACKSPACE, SDLK_INSERT, SDLK_DELETE, SDLK_UP},
		{SDLK_TAB, SDLK_q, SDLK_w, SDLK_e, SDLK_r, SDLK_t, SDLK_y, SDLK_u, SDLK_i, SDLK_o, SDLK_p, SDLK_LEFTBRACKET, SDLK_RIGHTBRACKET, SDLK_BACKSLASH, SDLK_HOME, SDLK_END, SDLK_DOWN},
		{SDLK_CAPSLOCK, SDLK_a, SDLK_s, SDLK_d, SDLK_f, SDLK_g, SDLK_h, SDLK_j, SDLK_k, SDLK_l, SDLK_SEMICOLON, SDLK_QUOTE, SDLK_RETURN, SDLK_PAGEUP, SDLK_LEFT},
		{SDLK_LSHIFT, SDLK_z, SDLK_x, SDLK_c, SDLK_v, SDLK_b, SDLK_n, SDLK_m, SDLK_COMMA, SDLK_PERIOD, SDLK_SLASH, SDLK_RSHIFT, SDLK_PAGEDOWN, SDLK_RIGHT},
		{SDLK_LCTRL, SDLK_LSUPER, SDLK_LALT, SDLK_SPACE, SDLK_RALT, SDLK_RSUPER, SDLK_MENU, SDLK_RCTRL}
	}, {
		{SDLK_ESCAPE, SDLK_F1, SDLK_F2, SDLK_F3, SDLK_F4, SDLK_F5, SDLK_F6, SDLK_F8, SDLK_F9, SDLK_F10, SDLK_F11, SDLK_F12},
		{'~', SDLK_EXCLAIM, SDLK_AT, SDLK_HASH, SDLK_DOLLAR, '%', SDLK_CARET, SDLK_AMPERSAND, SDLK_ASTERISK, SDLK_LEFTPAREN, SDLK_RIGHTPAREN, SDLK_UNDERSCORE, SDLK_PLUS, SDLK_BACKSPACE, SDLK_INSERT, SDLK_DELETE, SDLK_UP},
		{SDLK_TAB, SDLK_q, SDLK_w, SDLK_e, SDLK_r, SDLK_t, SDLK_y, SDLK_u, SDLK_i, SDLK_o, SDLK_p, '{', '}', '|', SDLK_HOME, SDLK_END, SDLK_DOWN},
		{SDLK_CAPSLOCK, SDLK_a, SDLK_s, SDLK_d, SDLK_f, SDLK_g, SDLK_h, SDLK_j, SDLK_k, SDLK_l, SDLK_COLON, SDLK_QUOTEDBL, SDLK_RETURN, SDLK_PAGEUP, SDLK_LEFT},
		{SDLK_LSHIFT, SDLK_z, SDLK_x, SDLK_c, SDLK_v, SDLK_b, SDLK_n, SDLK_m, SDLK_LESS, SDLK_GREATER, SDLK_QUESTION, SDLK_RSHIFT, SDLK_PAGEDOWN, SDLK_RIGHT},
		{SDLK_LCTRL, SDLK_LSUPER, SDLK_LALT, SDLK_SPACE, SDLK_RALT, SDLK_RSUPER, SDLK_MENU, SDLK_RCTRL}
	}
};

static char* syms[2][NUM_ROWS][NUM_KEYS] = {
	{
		{"esc",   "F1",  "F2",  "F3",    "F4",  "F5",  "F6",   "F7", "F8", "F9", "F10", "F11", "F12", NULL},
		{"`",     "1",   "2",   "3",     "4",   "5",   "6",    "7",  "8",  "9",  "0",   "-",   "=",     "bksp", "ins",  "del", " ^ ", NULL},
		{"tab",   "q",   "w",   "e",     "r",   "t",   "y",    "u",  "i",  "o",  "p",   "[",   "]",     "\\",   "home", "end", " \xde ", NULL},
		{"caps",  "a",   "s",   "d",     "f",   "g",   "h",    "j",  "k",  "l",  ";",   "'",   "enter", "pg up", " < ", NULL},
		{"shift", "z",   "x",   "c",     "v",   "b",   "n",    "m",  ",",  ".",  "/",   " shift", "pg dn", " > ", NULL},
		{"ctrl",  "win", "alt", "   space   ", "alt", "win", "menu", "ctrl", NULL}
	}, {
		{"esc",   "F1",  "F2",  "F3",    "F4",  "F5",  "F6",   "F7", "F8", "F9", "F10", "F11", "F12", NULL},
		{"~",     "!",   "@",   "#",     "$",   "%",   "^",    "&",  "*",  "(",  ")",   "_",   "+",     "bksp", "ins",  "del", " ^ ", NULL},
		{"tab",   "Q",   "W",   "E",     "R",   "T",   "Y",    "U",  "I",  "O",  "P",   "{",   "}",     "|",   "home", "end", " \xde ", NULL},
		{"caps",  "A",   "S",   "D",     "F",   "G",   "H",    "J",  "K",  "L",  ":",   "\"",   "enter", "pg up", " < ", NULL},
		{"shift", "Z",   "X",   "C",     "V",   "B",   "N",    "M",  "<",  ">",  "?",   " shift", "pg dn", " > ", NULL},
		{"ctrl",  "win", "alt", "   space   ", "alt", "win", "menu", "ctrl", NULL}
	}
};

static unsigned char toggled[NUM_ROWS][NUM_KEYS];

static int selected_i = 0, selected_j = 0;
static int shifted = 0;
static int location = 0;
static int active = 1;
static int mod_state = 0;
static int show_help = 1;

void init_keyboard() {
	for(int j = 0; j < NUM_ROWS; j++)
		for(int i = 0; i < NUM_KEYS; i++)
			toggled[j][i] = 0;
	selected_i = selected_j = shifted = location = 0;
	active = 1;
	mod_state = 0;

}

char* help = 
"How to use:\n"
"  ARROWS: select key from keyboard\n"
"  A: press key\n"
"  B: toggle key (useful for shift/ctrl...)\n"
"  L: shift\n"
"  R: backspace\n"
"  Y: change keyboard location (top/bottom)\n"
"  X: show / hide keyboard\n"
"  SELECT: quit\n"
"  START: show this help\n\n"
"Cheatcheet (tutorial at www.shellscript.sh):\n"
"  TAB key         complete path\n"
"  UP/DOWN keys    navigate history\n"
"  pwd             print current directory\n"
"  ls              list files (-l for file size)\n"
"  cd <d>          change directory (.. = go up)\n"
"  cp <f> <d>      copy files (dest can be dir)\n"
"  mv <f> <d>      move files (dest can be dir)\n"
"  rm <f>          remove files (use -rf for dir)\n"
"  top             see running processes (q to quit)\n"
"  more <f>        see content of text file\n"
"  file <f>        see type of file\n"
"  opkg install <f.ipk>  install package\n"
"  opkg remove <f>       remove package\n"
"  grep <pattern> <f>    find in files\n"
;

void draw_keyboard(SDL_Surface* surface) {
	unsigned short bg_color = SDL_MapRGB(surface->format, 64, 64, 64);
	unsigned short key_color = SDL_MapRGB(surface->format, 128, 128, 128);
	unsigned short text_color = SDL_MapRGB(surface->format, 0, 0, 0);
	unsigned short sel_color = SDL_MapRGB(surface->format, 128, 255, 128);
	unsigned short sel_toggled_color = SDL_MapRGB(surface->format, 255, 255, 128);
	unsigned short toggled_color = SDL_MapRGB(surface->format, 192, 192, 0);
	if(show_help) {
		SDL_FillRect(surface, NULL, bg_color);
		draw_string(surface, "SDL Terminal by Benob, based on st-sdl", 42, 10, sel_toggled_color);
		draw_string(surface, help, 8, 28, sel_color);
		return;
	}
	if(!active) return;
	int total_length = -1;
	for(int i = 0; i < NUM_KEYS && syms[0][0][i]; i++) {
		total_length += (1 + strlen(syms[0][0][i])) * 6;
	}
	int center_x = (surface->w - total_length) / 2;
	int x = center_x, y = surface->h - 8 * (NUM_ROWS) - 16;
	if(location == 1) y = 16;

	SDL_Rect rect = {x - 4, y - 3, total_length + 3, NUM_ROWS * 8 + 3};
	SDL_FillRect(surface, &rect, bg_color);

	for(int j = 0; j < NUM_ROWS; j++) {
		x = center_x;
		for(int i = 0; i < row_length[j]; i++) {
			int length = strlen(syms[shifted][j][i]);
			SDL_Rect r2 = {x - 2, y - 1, length * 6 + 4, 7};
			if(toggled[j][i]) {
				if(selected_i == i && selected_j == j) {
					SDL_FillRect(surface, &r2, sel_toggled_color);
				} else {
					SDL_FillRect(surface, &r2, toggled_color);
				}
			} else if(selected_i == i && selected_j == j) {
				SDL_FillRect(surface, &r2, sel_color);
			} else {
				SDL_FillRect(surface, &r2, key_color);
			}
			draw_string(surface, syms[shifted][j][i], x, y, text_color);
			x += 6 * (length + 1);
		}
		y += 8;
	}
}

enum { STATE_TYPED, STATE_UP, STATE_DOWN };

void update_modstate(int key, int state) {
	//SDLMod mod_state = SDL_GetModState();
	if(state == STATE_DOWN) {
		if(key == SDLK_LSHIFT) mod_state |= KMOD_LSHIFT;
		else if(key == SDLK_RSHIFT) mod_state |= KMOD_RSHIFT;
		else if(key == SDLK_LCTRL) mod_state |= KMOD_LCTRL;
		else if(key == SDLK_RCTRL) mod_state |= KMOD_RCTRL;
		else if(key == SDLK_LALT) mod_state |= KMOD_LALT;
		else if(key == SDLK_RALT) mod_state |= KMOD_RALT;
		else if(key == SDLK_LMETA) mod_state |= KMOD_LMETA;
		else if(key == SDLK_RMETA) mod_state |= KMOD_RMETA;
		//else if(key == SDLK_NUM) mod_state |= KMOD_NUM;
		else if(key == SDLK_CAPSLOCK) mod_state |= KMOD_CAPS;
		else if(key == SDLK_MODE) mod_state |= KMOD_MODE;
	} else if(state == STATE_UP) {
		if(key == SDLK_LSHIFT) mod_state &= ~KMOD_LSHIFT;
		else if(key == SDLK_RSHIFT) mod_state &= ~KMOD_RSHIFT;
		else if(key == SDLK_LCTRL) mod_state &= ~KMOD_LCTRL;
		else if(key == SDLK_RCTRL) mod_state &= ~KMOD_RCTRL;
		else if(key == SDLK_LALT) mod_state &= ~KMOD_LALT;
		else if(key == SDLK_RALT) mod_state &= ~KMOD_RALT;
		else if(key == SDLK_LMETA) mod_state &= ~KMOD_LMETA;
		else if(key == SDLK_RMETA) mod_state &= ~KMOD_RMETA;
		//else if(key == SDLK_NUM) mod_state &= ~KMOD_NUM;
		else if(key == SDLK_CAPSLOCK) mod_state &= ~KMOD_CAPS;
		else if(key == SDLK_MODE) mod_state &= ~KMOD_MODE;
	}
	SDL_SetModState(mod_state);
}

void simulate_key(int key, int state) {
	update_modstate(key, state);
	unsigned short unicode = 0;
	if(key < 128) {
		unicode = key;
	}
	SDL_Event event = {
		.key = {
			.type = SDL_KEYDOWN,
			.state = SDL_PRESSED,
			.keysym = {
				.scancode = 0,
				.sym = key,
				.mod = KMOD_SYNTHETIC,
				.unicode = unicode,
			}
		}
	};
	if(state == STATE_TYPED) {
		SDL_PushEvent(&event);
		event.key.type = SDL_KEYUP;
		event.key.state = SDL_RELEASED;
	} else if(state == STATE_UP) {
		event.key.type = SDL_KEYUP;
		event.key.state = SDL_RELEASED;
	}
	SDL_PushEvent(&event);
	//printf("%d\n", key);
}

int compute_visual_offset(int col, int row) {
	int sum = 0;
	for(int i = 0; i < col; i++) sum += 1 + strlen(syms[0][row][i]);
	sum += (1 + strlen(syms[0][row][col])) / 2;
	return sum;
}

int compute_new_col(int visual_offset, int old_row, int new_row) {
	int new_sum = 0;
	int new_col = 0;
	while(new_col < row_length[new_row] - 1 && new_sum + (1 + strlen(syms[0][new_row][new_col])) / 2 < visual_offset) {
		new_sum += 1 + strlen(syms[0][new_row][new_col]);
		new_col++;
	}
	return new_col;
}

int handle_keyboard_event(SDL_Event* event) {
	static int visual_offset = 0;
	if(event->key.type == SDL_KEYDOWN && !(event->key.keysym.mod & KMOD_SYNTHETIC) && event->key.keysym.sym == KEY_ACTIVATE) {
		active = ! active;
		return 1;
	}
	if(!active) return 0;
	if((event->key.type == SDL_KEYUP || event->key.type == SDL_KEYDOWN) && event->key.keysym.mod & KMOD_SYNTHETIC) return 0;

	if(event->key.type == SDL_KEYDOWN && event->key.state == SDL_PRESSED) {
		if(show_help) {
			// do nothing
		} else if(event->key.keysym.sym == KEY_QUIT) {
			exit(0);
		} else if(event->key.keysym.sym == KEY_HELP) {
			show_help = 1;
		} else if(event->key.keysym.sym == KEY_UP && selected_j > 0) {
			selected_i = compute_new_col(visual_offset, selected_j, selected_j - 1);
			selected_j--;
			//selected_i = selected_i * row_length[selected_j] / row_length[selected_j + 1];
		} else if(event->key.keysym.sym == KEY_DOWN && selected_j < NUM_ROWS - 1) {
			selected_i = compute_new_col(visual_offset, selected_j, selected_j + 1);
			selected_j++;
			//selected_i = selected_i * row_length[selected_j] / row_length[selected_j - 1];
		} else if(event->key.keysym.sym == KEY_LEFT && selected_i > 0) {
			selected_i--;
			visual_offset = compute_visual_offset(selected_i, selected_j);
		} else if(event->key.keysym.sym == KEY_RIGHT && selected_i < row_length[selected_j] - 1) {
			selected_i++;
			visual_offset = compute_visual_offset(selected_i, selected_j);
		} else if(event->key.keysym.sym == KEY_SHIFT) {
			shifted = 1;
			toggled[4][0] = 1;
			update_modstate(SDLK_LSHIFT, STATE_DOWN);
		} else if(event->key.keysym.sym == KEY_LOCATION) {
			location = !location;
		} else if(event->key.keysym.sym == KEY_BACKSPACE) {
			simulate_key(SDLK_BACKSPACE, STATE_TYPED);
		} else if(event->key.keysym.sym == KEY_TOGGLE) {
			toggled[selected_j][selected_i] = 1 - toggled[selected_j][selected_i];
			if(toggled[selected_j][selected_i]) simulate_key(keys[shifted][selected_j][selected_i], STATE_DOWN);
			else simulate_key(keys[shifted][selected_j][selected_i], STATE_UP);
			if(selected_j == 4 && (selected_i == 0 || selected_i == 11)) shifted = toggled[selected_j][selected_i];
		} else if(event->key.keysym.sym == KEY_ENTER) {
			int key = keys[shifted][selected_j][selected_i];
			if(mod_state & KMOD_CTRL) {
				if (key >= 64 && key < 64 + 32) simulate_key(key - 64, STATE_DOWN);
				else if (key >= 97 && key < 97 + 31) simulate_key(key - 96, STATE_DOWN);
			} else if(mod_state & KMOD_SHIFT && key >= SDLK_a && key <= SDLK_z) {
				simulate_key(key - SDLK_a + 'A', STATE_TYPED);
			} else {
				simulate_key(key, STATE_TYPED);
			}
		}
	} else if(event->key.type == SDL_KEYUP || event->key.state == SDL_RELEASED) {
		if(show_help) {
			show_help = 0;
		} else if(event->key.keysym.sym == KEY_SHIFT) {
			shifted = 0;
			toggled[4][0] = 0;
			update_modstate(SDLK_LSHIFT, STATE_UP);
		}
	}
	return 1;
}

#ifdef TEST_KEYBOARD

int main() {
	SDL_Init( SDL_INIT_EVERYTHING );
	SDL_Surface* screen = SDL_SetVideoMode(320 * 4, 240 * 4, 16, SDL_SWSURFACE );
	SDL_Surface* buffer = SDL_CreateRGBSurface(SDL_SWSURFACE, 320, 240, 16, screen->format->Rmask, screen->format->Gmask, screen->format->Bmask, screen->format->Amask);
	while(1) {
		SDL_Event event;
		while( SDL_PollEvent( &event ) ) {
			if( event.type == SDL_QUIT ) { 
				return 0;
			} else {
				handle_keyboard_event(&event);
			}
		}
		SDL_Rect r = {0, 0, buffer->w, buffer->h};
		SDL_FillRect(buffer, &r, 0);
		draw_keyboard(buffer);
		SDL_LockSurface(buffer);
		for(int j = 0; j < buffer->h; j++) {
			for(int i = 0; i < buffer->w; i++) {
				SDL_Rect rect = {i * 4, j * 4, 4, 4};
				SDL_FillRect(screen, &rect, ((unsigned short*)buffer->pixels)[j * (buffer->pitch >> 1) + i]);
			}
		}
		SDL_UnlockSurface(buffer);
		SDL_Flip(screen);
		SDL_Delay(1000 / 30);
	}
	SDL_Quit();
}

#endif