clock_*(): New functions

And create and draw the clock on the screen.

5 files changed, 262 insertions, 1 deletions

diff --git a/src/clock.c b/src/clock.c
new file mode 100644
index 0000000..0e6085c
--- /dev/null
+++ b/src/clock.c
@@ -0,0 +1,198 @@
+/*
+ * Clock screen functions
+ *
+ * Copyright (C) 2019  Patrick McDermott
+ *
+ * This file is part of Timeteller.
+ *
+ * Timeteller 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.
+ *
+ * Timeteller 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 Timeteller.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "clock.h"
+
+#include <assert.h>
+#include <curses.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <time.h>
+
+#include "screen.h"
+
+#define MIN(a, b) (((a) < (b)) ? (a) : (b))
+
+#define NUM_DIGITS   6
+#define NUM_COLONS   2
+#define DIGIT_HEIGHT 5
+#define DIGIT_WIDTH  3
+#define COLON_WIDTH  1
+#define SPACING      1
+
+static const uint16_t _clock_font[] = {
+	075557,  /* 0 */
+	011111,  /* 1 */
+	071747,  /* 2 */
+	071717,  /* 3 */
+	055711,  /* 4 */
+	074717,  /* 5 */
+	074757,  /* 6 */
+	071111,  /* 7 */
+	075757,  /* 8 */
+	075717,  /* 9 */
+	004040,  /* : */
+};
+#define COLON_DIGIT 10
+
+struct clock {
+	WINDOW *win;
+	int     begy;
+	int     begx;
+	int     font_size;
+};
+
+struct clock *
+clock_new(WINDOW *win)
+{
+	struct clock *clock;
+
+	clock = calloc(1, sizeof(*clock));
+	if (clock == NULL) {
+		return NULL;
+	}
+
+	if (clock_size(clock) == false) {
+		free(clock);
+		return NULL;
+	}
+
+	clock->win = win;
+
+	return clock;
+}
+
+bool
+clock_size(struct clock *clock)
+{
+	int win_h;
+	int win_w;
+	int clock_h;
+	int clock_w;
+
+	assert(clock);
+
+	getmaxyx(clock->win, win_h, win_w);
+	if (win_h < 0 && win_w < 0) {
+		win_h = LINES;
+		win_w = COLS;
+	}
+	clock_h = DIGIT_HEIGHT + SPACING * 2;
+	clock_w = NUM_DIGITS * (DIGIT_WIDTH + SPACING)
+	        + NUM_COLONS * (COLON_WIDTH + SPACING)
+	        + SPACING;
+	clock_w *= 2;  /* A "dot" is two columns wide.  */
+	if (win_h < clock_h || win_w < clock_w) {
+		return false;
+	}
+	clock->font_size = MIN(win_h / clock_h, win_w / clock_w);
+	clock_h *= clock->font_size;
+	clock_w *= clock->font_size;
+	clock->begy = (win_h - clock_h    ) / 2;
+	clock->begx = (win_w - clock_w + 1) / 2;
+
+	return true;
+}
+
+/* begy and begx are measured in dots from the top left corner of clock area. */
+static void
+_clock_draw_dot(struct clock *clock, int begy, int begx, int dot)
+{
+	chtype ch;
+	int y;
+	int x;
+
+	assert(clock);
+
+	ch = ' ' | (dot ? A_REVERSE : 0);
+
+	begy = clock->begy +  begy * clock->font_size;
+	begx = clock->begx + (begx * clock->font_size) * 2;
+	for (y = 0; y < clock->font_size; ++y) {
+		for (x = 0; x < clock->font_size; ++x) {
+			mvwaddch(clock->win, begy + y, begx + x * 2    , ch);
+			mvwaddch(clock->win, begy + y, begx + x * 2 + 1, ch);
+		}
+	}
+}
+
+/* begx is measured in dots from the left side of clock area.  */
+static void
+_clock_draw_digit(struct clock *clock, int begx, int d)
+{
+	int i;
+	int y;
+	int x;
+	int dot;
+
+	assert(clock);
+
+	for (i = 0; i < DIGIT_HEIGHT * DIGIT_WIDTH; ++i) {
+		y =    1 + i / DIGIT_WIDTH;
+		x = begx + i % DIGIT_WIDTH;
+		dot = _clock_font[d] & (1 << (DIGIT_HEIGHT*DIGIT_WIDTH-1-i));
+		_clock_draw_dot(clock, y, x, dot);
+	}
+}
+
+void
+clock_draw(struct clock *clock)
+{
+	time_t     t = 0;
+	struct tm *tm;
+	int        x;
+
+	assert(clock);
+
+	time(&t);
+	if (t < (time_t) 0) {
+		return;
+	}
+
+	tm = localtime(&t);
+	if (tm == NULL) {
+		return;
+	}
+
+	x = 0;
+	_clock_draw_digit(clock, x += SPACING              , tm->tm_hour / 10);
+	_clock_draw_digit(clock, x += SPACING + DIGIT_WIDTH, tm->tm_hour % 10);
+	_clock_draw_digit(clock, x += SPACING + DIGIT_WIDTH, COLON_DIGIT);
+	_clock_draw_digit(clock, x += SPACING + COLON_WIDTH, tm->tm_min / 10);
+	_clock_draw_digit(clock, x += SPACING + DIGIT_WIDTH, tm->tm_min % 10);
+	_clock_draw_digit(clock, x += SPACING + DIGIT_WIDTH, COLON_DIGIT);
+	_clock_draw_digit(clock, x += SPACING + COLON_WIDTH, tm->tm_sec / 10);
+	_clock_draw_digit(clock, x += SPACING + DIGIT_WIDTH, tm->tm_sec % 10);
+}
+
+struct clock *
+clock_destroy(struct clock **clock_p)
+{
+	struct clock *clock;
+
+	assert(clock_p && *clock_p);
+
+	clock = *clock_p;
+
+	free(clock);
+	return clock = NULL;
+}
diff --git a/src/clock.h b/src/clock.h
new file mode 100644
index 0000000..eedda1c
--- /dev/null
+++ b/src/clock.h
@@ -0,0 +1,44 @@
+/*
+ * Clock screen functions
+ *
+ * Copyright (C) 2019  Patrick McDermott
+ *
+ * This file is part of Timeteller.
+ *
+ * Timeteller 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.
+ *
+ * Timeteller 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 Timeteller.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef CLOCK_H_
+#define CLOCK_H_
+
+#include <curses.h>
+#include <stdbool.h>
+
+#include "screen.h"
+
+struct clock;
+
+struct clock *
+clock_new(WINDOW *win);
+
+bool
+clock_size(struct clock *clock);
+
+void
+clock_draw(struct clock *clock);
+
+struct clock *
+clock_destroy(struct clock **clock_p);
+
+#endif  /* CLOCK_H_ */
diff --git a/src/local.mk b/src/local.mk
index d9142ac..0429b52 100644
--- a/src/local.mk
+++ b/src/local.mk
@@ -1,4 +1,6 @@
 timeteller_SOURCES += \
+	%reldir%/clock.c \
+	%reldir%/clock.h \
 	%reldir%/main.c \
 	%reldir%/screen.c \
 	%reldir%/screen.h \
diff --git a/src/main.c b/src/main.c
index 673dd24..a3118db 100644
--- a/src/main.c
+++ b/src/main.c
@@ -67,6 +67,7 @@ main(int argc, char **argv)
 
 	screen = screen_new();
 
+	screen_draw(screen);
 	speech_play_time(speech);
 
 	screen_destroy(&screen);
diff --git a/src/screen.c b/src/screen.c
index a8b8b26..f705701 100644
--- a/src/screen.c
+++ b/src/screen.c
@@ -25,8 +25,11 @@
 #include <curses.h>
 #include <stdlib.h>
 
+#include "clock.h"
+
 struct screen {
-	WINDOW *win;
+	WINDOW       *win;
+	struct clock *clock;
 };
 
 struct screen *
@@ -46,12 +49,23 @@ screen_new(void)
 	}
 	curs_set(0);  /* Ignore errors.  */
 
+	screen->clock = clock_new(screen->win);
+	if (screen->clock == NULL) {
+		free(screen);
+		return NULL;
+	}
+
 	return screen;
 }
 
 void
 screen_draw(struct screen *screen)
 {
+	assert(screen);
+
+	clock_draw(screen->clock);
+
+	refresh();
 }
 
 struct screen *
@@ -66,6 +80,8 @@ screen_destroy(struct screen **screen_p)
 	delwin(screen->win);
 	endwin();
 
+	clock_destroy(&screen->clock);
+
 	free(screen);
 	return screen = NULL;
 }