Initial Commit

2 files changed, 252 insertions, 0 deletions

diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..b974136
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,2 @@
+0x800: main.c
+	gcc main.c -o 0x800
diff --git a/main.c b/main.c
new file mode 100644
index 0000000..0273894
--- /dev/null
+++ b/main.c
@@ -0,0 +1,250 @@
+#include<stdio.h>
+#include<stdlib.h>
+#include<time.h>
+#include<unistd.h>
+#include<termios.h>
+/*
+ *macro for random number from 0, up to but not including x, however this does
+ *not guarantee absolute equal distribution as RAND_MAX % x isn't guaranteed to
+ *be x-1, so all values up to and including RAND_MAX %x will have a slight
+ *advantage
+ */
+#define r(x) (rand() % x)
+/*
+ * Stores the state of the game
+ */
+unsigned int field[4][4] = {0};
+//if victory is 1, then 2048 has been found, if -1, then we ran out of space
+int victory = 0;
+//loop var
+int loop = 1;
+/*
+ * Adds another value randomly to board, if this can not be done declare lose
+ * condition. It also looks for 2048 and handles the win condition
+ */
+void addlose() {
+	// Number of empty spaces left, it this is 0 then this function will
+	// handle the lose condition/ death screen
+	int empty = 0;
+	//loops through and counts empty spaces
+	for (int i = 0; i <4 ; i++) {
+		for (int j =0; j < 4; j++) {
+			if (field[i][j] == 0) {
+				empty++;
+			}
+			//victory detected
+			if (field[i][j] == 2048) {
+				loop = 0;
+				victory = 1;
+				return;
+			}
+		}
+	}
+	//no empty spaces left, lose
+	if (empty == 0) {
+		loop = 0;
+		victory = -1;
+		return;
+	}
+	int  addfield  = r(empty);
+	int k = 0;
+	for (int i = 0; i < 4; i++) {
+		for (int j = 0; j < 4; j++) {
+			//the kth empty field has been found
+			if (field[i][j] == 0) {
+				if ( k == addfield) {
+					field[i][j] = 2;
+				}
+				k++;
+			}
+		}
+	}
+}
+/*
+ * Shifts the values in field according to dx and dy, handles all logic even for
+ * the case where there is no shift. Returns 1 if it has shifted, return 0 if
+ * not.
+ */
+int shift (int dx, int dy) {
+	//if there is no shift, return
+	if (dx == 0 && dy == 0) {
+		return 0;
+	}
+	int shift = 0;
+	//initial and final x and y values
+	int xi, xf, yi, yf = 0;
+	//increment values, default to going low to high
+	int di, dj = 1;
+	/*
+	 * We want it to go from highest x to lowest x if dx is positive, and
+	 * the opposite if it's negative, likewise for y values
+	 */
+	if (dx > 0) {
+		di = -1;
+		xi = 3;
+		xf = -1;
+	} else {
+		di = 1;
+		xi = 0;
+		xf = 4;
+	}
+	if (dy > 0) {
+		dj = -1;
+		yi = 3;
+		yf = -1;
+	} else {
+		dj = 1;
+		yi = 0;
+		yf = 4;
+	}
+	//loops through and does all the shifting
+	for (int i = xi; i != xf; i += di) {
+		for (int j = yi; j != yf; j += dj) {
+			//finds prime field to compare to
+			int xp = i + dx;
+			int yp = j + dy;
+			//checks that there's an actual shift and that it's in
+			//bounds
+			if (xp == i && yp == j) {
+				//don't do anything
+			} else if (xp < 0 || xp > 3 || yp < 0 || yp > 3) {
+				//don't do anythign either
+			} else {
+				//it shifts and it's in bound
+				//check to see if you should merge
+				if (field[xp][yp] == 0 || 
+					field[xp][yp] == field[i][j]) {
+					//make shift not 0 if that wasn't a zero
+					//being shifted
+					if (field[i][j] != 0) {
+						shift = 1;
+					}
+					//add the current field to the
+					//transformed field, then set current
+					//field to 0 so somebody else can move
+					//in.
+					field[xp][yp] += field[i][j];
+					field[i][j] = 0;
+				}
+			}
+
+		}
+	}
+	return shift;
+}
+int main (int argc, char * argv[]) {
+	//seeding RNG with time
+	srand(time(NULL));
+	//initializes the game board
+	field[r(4)][r(4)] = 2;
+	//sets raw tty mode
+	struct termios term;
+	tcgetattr(STDIN_FILENO, &term);
+	struct termios old_term = term;
+	cfmakeraw(&term);
+	tcsetattr(STDIN_FILENO, TCSANOW, &term);
+	while (loop) {
+		//clears the screen
+		printf("\033[2J");
+		//homes the cursor
+		printf("\033[H");
+		//displays the field
+		for (int i =0; i < 4; i ++) {
+			for (int j = 0; j < 4; j++) {
+				//adds color
+				switch (field[j][i]) {
+					case 0:
+						printf("\033[31m");
+					break;
+					case 2:
+						printf("\033[32m");
+					break;
+					case 4:
+						printf("\033[33m");
+					break;
+					case 8:
+						printf("\033[34m");
+					break;
+					case 16:
+						printf("\033[35m");
+					break;
+					case 32:
+						printf("\033[36m");
+					break;
+					case 64:
+						printf("\033[1;31m");
+					break;
+					case 128:
+						printf("\033[1;32m");
+					break;
+					case 256:
+						printf("\033[30m\033[41m");
+					break;
+					case 512:
+						printf("\033[30m\033[42m");
+					break;
+					case 1024:
+						printf("\033[30m\033[43m");
+					break;
+					case 2048:
+						printf("\033[30m\033[44m");
+					break;
+				}
+				printf("%.3X\033[0;39m\033[49m ",field[j][i]);
+			}
+			printf("\r\n\n");
+		}
+		//Determines the direction that blocks will attempt to move
+		int dx = 0;
+		int dy = 0;
+		//only reads one byte, may get messy with utf-8
+		char input;
+		read(STDIN_FILENO, &input, 1);
+		//write(STDOUT_FILENO, &input, 1);
+		//input handling
+		switch (input) {
+			case 'q':
+				loop = 0;
+			break;
+			
+			case 'h':
+				dx = -1;
+			break;
+			
+			case 'j':
+				dy = 1;
+			break;
+			
+			case 'k':
+				dy = -1;
+			break;
+			
+			case 'l':
+				dx = 1;
+			break;
+
+			default:
+			break;
+		}
+		//shifts until it can't shift anymore
+		while ( shift(dx,dy) ) {
+			//pass
+		}
+		//detects win/lose state, add another '2' to field otherwise
+		if (dx != 0 || dy != 0) {
+			addlose();
+		}
+	}
+	//Prints victory or defeat
+	if (victory == 1) {
+		printf("YOU WIN\r\n");
+	} else if (victory == -1) {
+		printf("YOU LOSE\r\n");
+	} else {
+		printf("Goodbye!\r\n");
+	}
+	//restores terminal state
+	printf("\033[0;39m\033[49m");
+	tcsetattr(STDIN_FILENO, TCSANOW, &old_term);
+	return 0;
+}