interface loop mostly done, added some helper methods

1 files changed, 126 insertions, 5 deletions

diff --git a/chess.c b/chess.c
index 5593d79..a4c728a 100644
--- a/chess.c
+++ b/chess.c
@@ -1,13 +1,33 @@
 #include <stdio.h>
 #include <stdlib.h>
-enum piece {
+typedef enum {
 	pawn = 1,
 	knight = 2,
 	bishop = 3,
 	rook = 4,
 	queen = 5,
-	king = 6
-};
+	king = 6,
+} piece_t;
+typedef struct Vector {
+	int mx;
+	int my;	
+} vector_t;
+vector_t init_vector(int mx, int my) {
+	vector_t vector;
+	vector.mx = mx;
+	vector.my = my;
+	return vector;
+}
+typedef struct VectorP {
+	vector_t* vectors;
+	int length;
+} vectorp_t;
+vectorp_t init_vectorp(vector_t* vectors, int length) {
+	vectorp_t vectorP;
+	vectorP.vectors = vectors;
+	vectorP.length = length;
+	return vectorP;
+}
 void draw_board(int board[8][8]) {
 	printf("  ABCDEFGH\n");
 	for(int r = 0; r < 8; r++) {
@@ -71,6 +91,76 @@ void draw_board(int board[8][8]) {
 		free(line);
 	}
 }
+int in_board(vector_t position) {
+	return position.mx < 8 && position.mx >= 0 && position.my < 8 && position.my >= 0;
+}
+int is_empty(int board[8][8], vector_t position) {
+	return board[position.mx][position.my] == 0;
+}
+vectorp_t get_moves(int board[8][8], vector_t position, piece_t piece) {
+	vector_t* moves = malloc(27 * sizeof(vector_t));
+	int moveCount = 0;
+	if(piece == pawn) {
+		vector_t move1 = init_vector(position.mx, position.my - 1);
+		if(in_board(move1) && is_empty(board, move1)) {
+			moves[0] = move1;
+			moveCount++;
+			if(position.my == 6) {
+				vector_t move2 = init_vector(position.mx, position.my - 2);
+				if(is_empty(board, move2)) {
+					moves[1] = move2;
+					moveCount++;
+				}
+			}
+		}
+		return init_vectorp(moves, moveCount);
+	}
+	else if(piece == pawn + 6) {
+		vector_t move1 = init_vector(position.mx, position.my + 1);
+		if(in_board(move1) && is_empty(board, move1)) {
+			moves[0] = move1;
+			moveCount++;
+			if(position.my == 1) {
+				vector_t move2 = init_vector(position.mx, position.my + 2);
+				if(is_empty(board, move2)) {
+					moves[1] = move2;
+					moveCount++;
+				}
+			}
+		}
+		return init_vectorp(moves, moveCount);
+	}
+}
+vector_t user_input_pos() {
+	char* inputString = malloc(3 * sizeof(char));
+	vector_t pos;
+	printf("Enter coordinates: ");
+	scanf("%2s", inputString);
+	for(int i = 0; i < 2; i++) {
+		if(inputString[i] <= '9' && inputString[i] >= '0') {
+			pos.my = 8 - (inputString[i] - '0');
+		}
+		else if(inputString[i] <= 'Z' && inputString[i] >= 'A') {
+			pos.mx = inputString[i] - 'A';
+		}
+		else if(inputString[i] <= 'z' && inputString[i] >= 'a') {
+			pos.mx = inputString[i] - 'a';
+		}
+		else {
+			return init_vector(-1, -1);
+		}
+	}
+	free(inputString);
+	return pos;
+}
+//converts board coordinates into algebraic notation
+char* get_readable_coords(vector_t position) {
+	char* output = malloc(3 * sizeof(char));
+	output[0] = 'A' + position.mx;
+	output[1] = '8' - position.my;
+	output[2] = '\0';
+	return output;
+}
 void clear_screen() {
 	system("@cls||clear");
 }
@@ -85,7 +175,38 @@ int main() {
 		{ knight + 6, pawn + 6, 0, 0, 0, 0, pawn, knight },
 		{ rook + 6, pawn + 6, 0, 0, 0, 0, pawn, rook }
 	}; 
-	clear_screen(board);
-	draw_board(board);
+	while(1) {
+		clear_screen(board);
+		draw_board(board);
+		printf("Enter the coordinates of the piece you want to move\n");
+		vector_t selection = user_input_pos();
+		int selectedPiece = board[selection.mx][selection.my];
+		if(selectedPiece == 0) {
+			continue;
+		}
+		printf("Selected piece: ");
+		printf("%d", selectedPiece);
+		printf("\n");
+		vectorp_t moves = get_moves(board, selection, selectedPiece);
+		if(moves.length == 0) {
+			continue;
+		}
+		printf("Valid moves: ");
+		for(int i = 0; i < moves.length; i++) {
+			char* readable_coords = get_readable_coords(moves.vectors[i]);
+			printf(readable_coords);
+			free(readable_coords);
+			printf("; ");
+		}
+		printf("\nEnter the coordinates you would like to move that piece to, or enter < to go back\n");
+		vector_t target = user_input_pos();
+		if(target.mx == -1) {
+			continue;
+		}
+		//TODO: check that target is in list of valid moves
+		board[selection.mx][selection.my] = 0;
+		board[target.mx][target.my] = selectedPiece;
+		printf("\n");
+	}	
 	return 0;
 }