cmd: Add 2048 game

Add the 2048 game, a good demo of ANSI sequences and a way to waste a
little time.

Bring it it from Barebox, modified for code style.

Signed-off-by: Simon Glass <sjg@chromium.org>

4 files changed, 410 insertions, 0 deletions

diff --git a/cmd/2048.c b/cmd/2048.c
new file mode 100644
index 0000000000..fa60aa94aa
--- /dev/null
+++ b/cmd/2048.c
@@ -0,0 +1,397 @@
+// SPDX-License-Identifier: MIT
+// SPDX-FileCopyrightText: © 2014 Maurits van der Schee
+
+/* Console version of the game "2048" for GNU/Linux */
+
+#include <common.h>
+#include <cli.h>
+#include <command.h>
+#include <rand.h>
+#include <linux/delay.h>
+
+#define SIZE 4
+static uint score;
+
+static void getColor(uint value, char *color, size_t length)
+{
+	u8 original[] = {
+		8, 255, 1, 255, 2, 255, 3, 255,
+		4, 255, 5, 255, 6, 255, 7, 255,
+		9, 0, 10, 0, 11, 0, 12, 0, 13,
+		0, 14, 0, 255, 0, 255, 0};
+	u8 *scheme = original;
+	u8 *background = scheme + 0;
+	u8 *foreground = scheme + 1;
+
+	if (value > 0) {
+		while (value >>= 1) {
+			if (background + 2 < scheme + sizeof(original)) {
+				background += 2;
+				foreground += 2;
+			}
+		}
+	}
+	snprintf(color, length, "\033[38;5;%d;48;5;%dm", *foreground,
+		 *background);
+}
+
+static void drawBoard(u16 board[SIZE][SIZE])
+{
+	int x, y;
+	char color[40], reset[] = "\033[0m";
+
+	printf("\033[H");
+	printf("2048.c %17d pts\n\n", score);
+
+	for (y = 0; y < SIZE; y++) {
+		for (x = 0; x < SIZE; x++) {
+			getColor(board[x][y], color, 40);
+			printf("%s", color);
+			printf("       ");
+			printf("%s", reset);
+		}
+		printf("\n");
+		for (x = 0; x < SIZE; x++) {
+			getColor(board[x][y], color, 40);
+			printf("%s", color);
+			if (board[x][y] != 0) {
+				char s[8];
+				s8 t;
+
+				snprintf(s, 8, "%u", board[x][y]);
+				t = 7 - strlen(s);
+				printf("%*s%s%*s", t - t / 2, "", s, t / 2, "");
+			} else {
+				printf("   ·   ");
+			}
+			printf("%s", reset);
+		}
+		printf("\n");
+		for (x = 0; x < SIZE; x++) {
+			getColor(board[x][y], color, 40);
+			printf("%s", color);
+			printf("       ");
+			printf("%s", reset);
+		}
+		printf("\n");
+	}
+	printf("\n");
+	printf("        ←, ↑, →, ↓ or q        \n");
+	printf("\033[A");
+}
+
+static int8_t findTarget(u16 array[SIZE], int x, int stop)
+{
+	int t;
+
+	/* if the position is already on the first, don't evaluate */
+	if (x == 0)
+		return x;
+	for (t = x - 1; t >= 0; t--) {
+		if (array[t]) {
+			if (array[t] != array[x]) {
+				/* merge is not possible, take next position */
+				return t + 1;
+			}
+			return t;
+		}
+
+		/* we should not slide further, return this one */
+		if (t == stop)
+			return t;
+	}
+	/* we did not find a */
+	return x;
+}
+
+static bool slideArray(u16 array[SIZE])
+{
+	bool success = false;
+	int x, t, stop = 0;
+
+	for (x = 0; x < SIZE; x++) {
+		if (array[x] != 0) {
+			t = findTarget(array, x, stop);
+			/*
+			 * if target is not original position, then move or
+			 * merge
+			 */
+			if (t != x) {
+				/*
+				 * if target is not zero, set stop to avoid
+				 * double merge
+				 */
+				if (array[t]) {
+					score += array[t] + array[x];
+					stop = t + 1;
+				}
+				array[t] += array[x];
+				array[x] = 0;
+				success = true;
+			}
+		}
+	}
+	return success;
+}
+
+static void rotateBoard(u16 board[SIZE][SIZE])
+{
+	s8 i, j, n = SIZE;
+	int tmp;
+
+	for (i = 0; i < n / 2; i++) {
+		for (j = i; j < n - i - 1; j++) {
+			tmp = board[i][j];
+			board[i][j] = board[j][n - i - 1];
+			board[j][n - i - 1] = board[n - i - 1][n - j - 1];
+			board[n - i - 1][n - j - 1] = board[n - j - 1][i];
+			board[n - j - 1][i] = tmp;
+		}
+	}
+}
+
+static bool moveUp(u16 board[SIZE][SIZE])
+{
+	bool success = false;
+	int x;
+
+	for (x = 0; x < SIZE; x++)
+		success |= slideArray(board[x]);
+
+	return success;
+}
+
+static bool moveLeft(u16 board[SIZE][SIZE])
+{
+	bool success;
+
+	rotateBoard(board);
+	success = moveUp(board);
+	rotateBoard(board);
+	rotateBoard(board);
+	rotateBoard(board);
+	return success;
+}
+
+static bool moveDown(u16 board[SIZE][SIZE])
+{
+	bool success;
+
+	rotateBoard(board);
+	rotateBoard(board);
+	success = moveUp(board);
+	rotateBoard(board);
+	rotateBoard(board);
+	return success;
+}
+
+static bool moveRight(u16 board[SIZE][SIZE])
+{
+	bool success;
+
+	rotateBoard(board);
+	rotateBoard(board);
+	rotateBoard(board);
+	success = moveUp(board);
+	rotateBoard(board);
+	return success;
+}
+
+static bool findPairDown(u16 board[SIZE][SIZE])
+{
+	bool success = false;
+	int x, y;
+
+	for (x = 0; x < SIZE; x++) {
+		for (y = 0; y < SIZE - 1; y++) {
+			if (board[x][y] == board[x][y + 1])
+				return true;
+		}
+	}
+
+	return success;
+}
+
+static int16_t countEmpty(u16 board[SIZE][SIZE])
+{
+	int x, y;
+	int count = 0;
+
+	for (x = 0; x < SIZE; x++) {
+		for (y = 0; y < SIZE; y++) {
+			if (board[x][y] == 0)
+				count++;
+		}
+	}
+	return count;
+}
+
+static bool gameEnded(u16 board[SIZE][SIZE])
+{
+	bool ended = true;
+
+	if (countEmpty(board) > 0)
+		return false;
+	if (findPairDown(board))
+		return false;
+	rotateBoard(board);
+	if (findPairDown(board))
+		ended = false;
+	rotateBoard(board);
+	rotateBoard(board);
+	rotateBoard(board);
+
+	return ended;
+}
+
+static void addRandom(u16 board[SIZE][SIZE])
+{
+	int x, y;
+	int r, len = 0;
+	u16 n, list[SIZE * SIZE][2];
+
+	for (x = 0; x < SIZE; x++) {
+		for (y = 0; y < SIZE; y++) {
+			if (board[x][y] == 0) {
+				list[len][0] = x;
+				list[len][1] = y;
+				len++;
+			}
+		}
+	}
+
+	if (len > 0) {
+		r = rand() % len;
+		x = list[r][0];
+		y = list[r][1];
+		n = ((rand() % 10) / 9 + 1) * 2;
+		board[x][y] = n;
+	}
+}
+
+static int test(void)
+{
+	u16 array[SIZE];
+	u16 data[] = {
+		0, 0, 0, 2,	2, 0, 0, 0,
+		0, 0, 2, 2,	4, 0, 0, 0,
+		0, 2, 0, 2,	4, 0, 0, 0,
+		2, 0, 0, 2,	4, 0, 0, 0,
+		2, 0, 2, 0,	4, 0, 0, 0,
+		2, 2, 2, 0,	4, 2, 0, 0,
+		2, 0, 2, 2,	4, 2, 0, 0,
+		2, 2, 0, 2,	4, 2, 0, 0,
+		2, 2, 2, 2,	4, 4, 0, 0,
+		4, 4, 2, 2,	8, 4, 0, 0,
+		2, 2, 4, 4,	4, 8, 0, 0,
+		8, 0, 2, 2,	8, 4, 0, 0,
+		4, 0, 2, 2,	4, 4, 0, 0
+	};
+	u16 *in, *out;
+	u16 t, tests;
+	int i;
+	bool success = true;
+
+	tests = (sizeof(data) / sizeof(data[0])) / (2 * SIZE);
+	for (t = 0; t < tests; t++) {
+		in = data + t * 2 * SIZE;
+		out = in + SIZE;
+		for (i = 0; i < SIZE; i++)
+			array[i] = in[i];
+		slideArray(array);
+		for (i = 0; i < SIZE; i++) {
+			if (array[i] != out[i])
+				success = false;
+		}
+		if (!success) {
+			for (i = 0; i < SIZE; i++)
+				printf("%d ", in[i]);
+			printf(" = > ");
+			for (i = 0; i < SIZE; i++)
+				printf("%d ", array[i]);
+			printf("expected ");
+			for (i = 0; i < SIZE; i++)
+				printf("%d ", in[i]);
+			printf(" = > ");
+			for (i = 0; i < SIZE; i++)
+				printf("%d ", out[i]);
+			printf("\n");
+			break;
+		}
+	}
+	if (success)
+		printf("All %u tests executed successfully\n", tests);
+
+	return !success;
+}
+
+static int do_2048(struct cmd_tbl *cmdtp, int flag, int argc,
+		   char *const argv[])
+{
+	struct cli_ch_state cch_s, *cch = &cch_s;
+	u16 board[SIZE][SIZE];
+	bool success;
+
+	if (argc == 2 && strcmp(argv[1], "test") == 0)
+		return test();
+
+	score = 0;
+
+	printf("\033[?25l\033[2J\033[H");
+
+	memset(board, 0, sizeof(board));
+	addRandom(board);
+	addRandom(board);
+	drawBoard(board);
+	cli_ch_init(cch);
+	while (true) {
+		int c;
+
+		c = cli_ch_process(cch, 0);
+		if (!c) {
+			c = getchar();
+			c = cli_ch_process(cch, c);
+		}
+		switch (c) {
+		case CTL_CH('b'): /* left arrow */
+			success = moveLeft(board);
+			break;
+		case CTL_CH('f'): /* right arrow */
+			success = moveRight(board);
+			break;
+		case CTL_CH('p'):/* up arrow */
+			success = moveUp(board);
+			break;
+		case CTL_CH('n'): /* down arrow */
+			success = moveDown(board);
+			break;
+		default:
+			success = false;
+		}
+		if (success) {
+			drawBoard(board);
+			mdelay(150);
+			addRandom(board);
+			drawBoard(board);
+			if (gameEnded(board)) {
+				printf("         GAME OVER          \n");
+				break;
+			}
+		}
+		if (c == 'q') {
+			printf("            QUIT            \n");
+			break;
+		}
+	}
+
+	printf("\033[?25h");
+
+	return 0;
+}
+
+U_BOOT_CMD(
+	2048,	2,	1,	do_2048,
+	"The 2048 game",
+	"Use your arrow keys to move the tiles. When two tiles with "
+	"the same number touch, they merge into one!"
+);
diff --git a/cmd/Kconfig b/cmd/Kconfig
index 091a0ee21a..e45b8847ae 100644
--- a/cmd/Kconfig
+++ b/cmd/Kconfig
@@ -1941,6 +1941,17 @@ endif
 
 menu "Misc commands"
 
+config CMD_2048
+	bool "Play 2048"
+	help
+	  This is a simple sliding block puzzle game designed by Italian web
+	  developer Gabriele Cirulli. The game's objective is to slide numbered
+	  tiles on a grid to combine them to create a tile with the number
+	  2048.
+
+	  This needs ANSI support on your terminal to work. It is not fully
+	  functional on a video device.
+
 config CMD_BMP
 	bool "Enable 'bmp' command"
 	depends on VIDEO
diff --git a/cmd/Makefile b/cmd/Makefile
index 054ef42017..6c37521b4e 100644
--- a/cmd/Makefile
+++ b/cmd/Makefile
@@ -12,6 +12,7 @@ obj-y += panic.o
 obj-y += version.o
 
 # command
+obj-$(CONFIG_CMD_2048) += 2048.o
 obj-$(CONFIG_CMD_ACPI) += acpi.o
 obj-$(CONFIG_CMD_ADDRMAP) += addrmap.o
 obj-$(CONFIG_CMD_AES) += aes.o
diff --git a/configs/sandbox_defconfig b/configs/sandbox_defconfig
index 3a1f14c60f..ca95b2c5d2 100644
--- a/configs/sandbox_defconfig
+++ b/configs/sandbox_defconfig
@@ -340,3 +340,4 @@ CONFIG_TEST_FDTDEC=y
 CONFIG_UNIT_TEST=y
 CONFIG_UT_TIME=y
 CONFIG_UT_DM=y
+CONFIG_CMD_2048=y