Starting work on LCD library

4 files changed, 118 insertions, 44 deletions

diff --git a/do_buildroot.sh b/do_buildroot.sh
index 1d26106..40c3f0b 100755
--- a/do_buildroot.sh
+++ b/do_buildroot.sh
@@ -7,8 +7,8 @@ overlay="$board/rootfs_overlay/"
 
 # Build configuration
 cp resources/buildroot.config "$BR/.config"
-# resources/linux.config
-cp resources/{post-build,ct1986}.sh resources/genimage-raspberrypi0.cfg resources/busybox.config "$board"
+#cp resources/linux.config resources/busybox.config "$board" # Causes recompile
+cp resources/{post-build,ct1986}.sh resources/genimage-raspberrypi0.cfg  "$board"
 
 # Overlay filesystem
 dirs="/usr/bin"
diff --git a/include/lcdlib.c b/include/lcdlib.c
new file mode 100644
index 0000000..a22a1e2
--- /dev/null
+++ b/include/lcdlib.c
@@ -0,0 +1,71 @@
+#include "lcdlib.h"
+
+// ===================================================================
+// Globals
+// ===================================================================
+
+static char previous_lines[LCD_HEIGHT][LCD_WIDTH+1];
+static FILE *lcd = NULL;
+static int line_idx;
+
+static const char* esc = "\x1B[L";
+
+int
+lcd_begin(void) {
+	lcd = fopen("/dev/lcd", "w");
+	if (lcd == NULL) return EXIT_FAILURE;
+	fprintf(lcd, "%sB", esc);
+	fflush(lcd);
+	lcd_clear();
+	return EXIT_SUCCESS;
+}
+
+void
+lcd_end(void) {
+	fclose(lcd);
+}
+
+void
+lcd_clear(void) {
+	line_idx = 0;
+	for (int y = 0; y + 1 < LCD_HEIGHT; y++) {
+		fprintf(lcd, "%sy%dx0;%sk", esc, y, esc);
+		previous_lines[y][0] = 0;
+	}
+	fflush(lcd);
+}
+
+void
+lcd_put_line(const enum LCD_WRITE_MODE mode, const char *line) {
+	if (mode == L_SCROLL && line_idx == LCD_HEIGHT) {
+		// If we're at the bottom, ``shift'' everything up
+		for (int y = 1; y < LCD_HEIGHT; y++) {
+			// Go to the start of row y, clear the line, and print the
+			// previous string there
+			fprintf(lcd, "%sy%dx0;%sk%s", esc, y-1, esc, previous_lines[y]);
+			// Overwrite the stored previous line with the next
+			strncpy(previous_lines[y-1], previous_lines[y], 16);
+		}
+		line_idx--;
+	}
+	// Go to the correct line, clear it, and write the input.
+	fprintf(lcd, "%sy%dx0;%sk%s", esc, line_idx, esc, line);
+	fflush(lcd);
+	// Store this line, null-terminate!
+	strncpy(previous_lines[line_idx], line, 16);
+	previous_lines[line_idx][16] = 0;
+	if (mode == L_SCROLL && line_idx < LCD_HEIGHT) line_idx++;
+}
+
+void
+lcd_printf_line(const enum LCD_WRITE_MODE mode,
+								const char *format, ...) {
+	char buf[16];
+
+	va_list(args);
+	va_start(args, format);
+	vsnprintf(buf, 16, format, args);
+	va_end(args);
+
+	lcd_put_line(mode, buf);
+}
diff --git a/include/lcdlib.h b/include/lcdlib.h
new file mode 100644
index 0000000..fd28a0e
--- /dev/null
+++ b/include/lcdlib.h
@@ -0,0 +1,19 @@
+#include <stdlib.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <string.h>
+
+#define LCD_WIDTH  16
+#define LCD_HEIGHT 2
+
+enum LCD_WRITE_MODE { L_OVERWRITE, L_SCROLL };
+
+int lcd_begin(void);
+void lcd_end(void);
+void lcd_clear(void);
+
+void lcd_put_line(const enum LCD_WRITE_MODE mode,
+									const char *line);
+
+void lcd_printf_line(const enum LCD_WRITE_MODE mode,
+										 const char *format, ...);
diff --git a/src/ct1986.c b/src/ct1986.c
index f697877..273fd98 100644
--- a/src/ct1986.c
+++ b/src/ct1986.c
@@ -1,23 +1,14 @@
 #include <stdlib.h>
-#include <stdio.h>
 #include <string.h>
 
 #include <tak.h>
 #include <negamax_cnn1986.h>
+#include <lcdlib.h>
 
-const char* esc = "\x1B[L";
-
-FILE *lcd = NULL;
 static char *gamelog = 0;
 static int human;
 
 static void
-write_line(const char *line) {
-	fprintf(lcd, "%s\n", line);
-	fflush(lcd);
-}
-
-static void
 append_to_gamelog(const char *line, const uint8_t win_line) {
 	// I _could_ dynamically compute the size but ... don't let
 	// `perfect' be the enemy of `good' ?
@@ -45,8 +36,7 @@ static void
 end_game(char *line, char *win) {
 	append_to_gamelog(line, 0);
 	append_to_gamelog(win, 1);
-	fprintf(lcd, "Game over: %s\n", win);
-	fflush(lcd);
+	lcd_printf_line(L_SCROLL, "Game over: %s", win);
 }
 
 static int
@@ -55,9 +45,9 @@ handle_turn(char *line) {
 	uint8_t new_win = (won == 0xFF);
 	switch (do_ptn(line)) {
 		// Errors
-		case PTN_INVALID:  { write_line("Invalid PTN.");  break; }
-		case ACT_ILLEGAL:  { write_line("Illegal ply.");  break; }
-		case ACT_OVERFLOW: { write_line("Overflow.");     break; }
+		case PTN_INVALID:  { lcd_put_line(L_SCROLL, "Invalid PTN.");  break; }
+		case ACT_ILLEGAL:  { lcd_put_line(L_SCROLL, "Illegal ply.");  break; }
+		case ACT_OVERFLOW: { lcd_put_line(L_SCROLL, "Overflow.");     break; }
 			// Game has ended
 		case GAME_END: {
 			// Did it end this turn?
@@ -71,7 +61,7 @@ handle_turn(char *line) {
 				}
 				return EXIT_SUCCESS;
 			} else {
-				write_line("Game over.");
+				lcd_put_line(L_SCROLL, "Game over.");
 				break;
 			}
 		}
@@ -87,7 +77,7 @@ handle_turn(char *line) {
 static void
 new_game(uint8_t size) {
 	reset_state(size);
-	write_line("New 5x5 game.");
+	lcd_put_line(L_SCROLL, "New 5x5 game.");
 	if (gamelog) gamelog = realloc(gamelog, sizeof(char));
 	else gamelog = malloc(sizeof(char));
 	gamelog[0] = 0;
@@ -95,34 +85,31 @@ new_game(uint8_t size) {
 
 // Set up output function for negamax_cnn1986
 static uint8_t perc;
+
 inline void
 negamax_cnn1986_display_progress(const uint8_t depth) {
 	if (depth == 0) {
 		perc++;
-		// back four spaces and clear line, followed by perc%
-		fprintf(lcd, "%sl%sl%sl%sl%sk%3d%%",
-						esc, esc, esc, esc, esc,
-						perc*4);
-		fflush(lcd);
+		lcd_printf_line(L_OVERWRITE, "Computing: %d%%", perc*4);
 	}
 }
 
 static int
 negamax_cnn1986_turn() {
 	// Prepare progress bar
-	fputs("Computing:     ", lcd); fflush(lcd);
+	lcd_put_line(L_SCROLL, "Computing: 0%");
 	// Run the minimax
 	perc = 0;
 	float minimax = negamax_cnn1986_generate();
-	fputc('\n', lcd); fflush(lcd);
 	// Failed to find a move?
 	if (minimax <= -infty) {
-		fprintf(lcd, "%s concedes!\n", (ply & 1) ? "Black" : "White");
+		lcd_printf_line(L_SCROLL, "%s concedes!",
+										(ply & 1) ? "Black" : "White");
 		return EXIT_FAILURE;
 	} else {
-		fprintf(lcd, "%s: %s\n",
-						(ply & 1) ? "Black" : "White",
-						negamax_cnn1986_ptn);
+		lcd_printf_line(L_SCROLL, "%s: %s",
+										(ply & 1) ? "Black" : "White",
+										negamax_cnn1986_ptn);
 		handle_turn(negamax_cnn1986_ptn);
 		return EXIT_SUCCESS;
 	}
@@ -130,7 +117,7 @@ negamax_cnn1986_turn() {
 
 static void
 do_game_log(void) {
-	fputs(gamelog, lcd);
+	lcd_put_line(L_SCROLL, "Not implemented.");
 }
 
 static int
@@ -138,14 +125,14 @@ input_is_not_turn(const char *line) {
 	switch (line[0]) {
 		case 'l': { do_game_log(); break; }
 		case 'n': { new_game(5);   break; }
-		case 'd': {
+		case 's': {
 			negamax_cnn1986_search_depth = line[1] - '0';
-			fprintf(lcd, "Search depth: %d\n", negamax_cnn1986_search_depth);
-			fflush(lcd);
+			lcd_printf_line(L_SCROLL, "Search depth: %d",
+											negamax_cnn1986_search_depth);
 			break;
 		}
-		case 'b': { human = 1; new_game(5); break; }
-		case 'w': { human = 0; new_game(5); break; }
+		case 'B': { human = 1; new_game(5); break; }
+		case 'W': { human = 0; new_game(5); break; }
 		default: return EXIT_FAILURE;
 	}
 	return EXIT_SUCCESS;
@@ -156,11 +143,8 @@ main(int argc, char **argv) {
 	(void)(argc);
 	(void)(argv);
 
-	lcd = fopen("/dev/lcd", "w");
-	if (lcd == NULL) return EXIT_FAILURE;
-
-	fprintf(lcd, "%sB", esc);
-	fflush(lcd);
+	if (lcd_begin() != EXIT_SUCCESS)
+		return EXIT_FAILURE;
 
 	human = 0;
 	negamax_cnn1986_search_depth = 3;
@@ -172,8 +156,8 @@ main(int argc, char **argv) {
 
 	for (int playing = 1; playing;) {
 		while (human == 0) {
-			if (ply & 1) write_line("Black: ");
-			else write_line("White: ");
+			if (ply & 1) lcd_put_line(L_SCROLL, "Black: ");
+			else lcd_put_line(L_SCROLL, "White: ");
 			read = getline(&line, &alloc_size, stdin);
 			if (read > 0) {
 				line[read - 1] = 0;
@@ -194,6 +178,6 @@ main(int argc, char **argv) {
 		}
 	}
 
-	fclose(lcd);
+	lcd_end();
 	return EXIT_SUCCESS;
 }