Merge pull request #5 from olin/frontend_init

Frontend init

src/.gitignore → .gitignore

@@ -5,3 +5,6 @@
 *.o
 *.a
 *.lib
+
+## VS Code
+.vscode/

src/Makefile

@@ -1,7 +1,7 @@
 CC=gcc
 CFLAGS+=-Wall
 # global includes
-# LDFLAGS+=
+# LDFLAGS+=-lncurses
 
 # add debug annotations, turn off optimizations, and #define DEBUG
 # use in bash with `DEBUG=1 make <foo>`
@@ -13,6 +13,13 @@ endif
 # link ncurses library
 # foo: LDFLAGS+=-lncurses
 
+# Generate .out files for easier .gitignore. Based on the default make rule
+# https://www.gnu.org/software/make/manual/html_node/Catalogue-of-Rules.html#Catalogue-of-Rules
+%.out: %.c
+	$(LINK.c) $^ $(LOADLIBES) $(LDLIBS) -o $@
+
+LINK.c = $(CC) $(CFLAGS) $(CPPFLAGS) $(LDFLAGS) $(TARGET_ARCH)
+
 # **GNU Make only** run all test files (any file ending in _test.c)
 # turns each `foo_test.c` into `.run-foo_test.c` with "Text Functions"
 test: $(patsubst %.c, .run-%.c, $(wildcard *_test.c))
@@ -27,5 +34,10 @@ test: $(patsubst %.c, .run-%.c, $(wildcard *_test.c))
 %_test: %_test.c minunit.h
 	$(CC) $(CFLAGS) $(LDFLAGS) -o $@ $^
 
+# frontend.out: frontend.c frontend.h
+# 	$(CC) frontend.c $(CFLAGS) $(LDLIBS) -o frontend.out
+frontend.out: cursor.o
+frontend.out: LDLIBS +=-lncurses
+
 clean:
-	-rm *.o *_test
+	-rm *.o *_test *.out

src/cursor.c

@@ -0,0 +1,71 @@
+#include <stdlib.h>
+#include <ncurses.h>
+#include "cursor.h"
+
+/* The Cursor struct helps with controls.
+ * It also maps the drawing area to the canvas nicely.
+ */
+
+Cursor *cursor_new() {
+    Cursor *cursor = malloc(sizeof(Cursor));
+    cursor->x = 0;
+    cursor->y = 0; 
+    return cursor;
+}
+
+void cursor_move_up(Cursor* cursor) {
+    if (cursor->y == 0) {
+        return;
+    }
+    cursor->y--;
+}
+
+void cursor_move_down(Cursor* cursor) {
+    if (cursor->y == (LINES - 2)) { // Take box lines into account
+        return;
+    }
+    cursor->y++;
+}
+
+void cursor_move_left(Cursor* cursor) {
+    if (cursor->x == 0) {
+        return;
+    }
+    cursor->x--;
+}
+
+void cursor_move_right(Cursor* cursor) {
+    if (cursor->x == (COLS - 2)) { // Take box lines into account
+        return;
+    }
+    cursor->x++;
+}
+
+int cursor_x_to_canvas(Cursor* cursor) {
+    return cursor->x + 1;
+}
+
+int cursor_y_to_canvas(Cursor* cursor) {
+    return cursor->y + 1;
+}
+
+void cursor_key_to_move(int arrow, Cursor *cursor) {
+    switch(arrow) {	
+        case KEY_LEFT:
+            cursor_move_left(cursor);
+            break;
+        case KEY_RIGHT:
+            cursor_move_right(cursor);
+            break;
+        case KEY_UP:
+            cursor_move_up(cursor);
+            break;
+        case KEY_DOWN:
+            cursor_move_down(cursor);
+            break;
+    }
+}
+
+void cursor_free(Cursor* cursor) {
+    free(cursor);
+}

src/cursor.h

@@ -0,0 +1,20 @@
+/* The Cursor struct helps with controls.
+ * It also maps the drawing area to the canvas nicely.
+ */
+
+typedef struct CURSOR {
+    int x;
+    int y;
+} Cursor;
+
+Cursor *cursor_new();
+void cursor_free(Cursor* cursor);
+
+void cursor_move_up(Cursor* cursor);
+void cursor_move_down(Cursor* cursor);
+void cursor_move_left(Cursor* cursor);
+void cursor_move_right(Cursor* cursor);
+
+int cursor_x_to_canvas(Cursor* cursor);
+int cursor_y_to_canvas(Cursor* cursor);
+void cursor_key_to_move(int arrow, Cursor *cursor);

src/frontend.c

@@ -0,0 +1,161 @@
+#include <stdlib.h>
+#include <signal.h>
+#include "frontend.h"
+#include "cursor.h"
+
+int STATUS_HEIGHT = 1;  // not including borders
+
+/* Layout
+ * ___________________________________________ 
+ * | 0 -- X, COLS                           | canvas window
+ * | |                                      |
+ * | Y, LINES                               |
+ * |                                        |
+ * |                                        |
+ * |                                        |
+ * |                                        |
+ * |                                        |
+ * |                                        |
+ * |________________________________________|  
+ * |                                        |  command window
+ * |________________________________________|
+ * */
+
+int main(int argc, char *argv[]) {
+    /* initialize your non-curses data structures here */
+
+    (void) signal(SIGINT, finish);      /* arrange interrupts to terminate */
+
+    (void) initscr();      /* initialize the curses library */
+    keypad(stdscr, TRUE);  /* enable keyboard mapping */
+    (void) nonl();         /* tell curses not to do NL->CR/NL on output */
+    (void) cbreak();       /* take input chars one at a time, no wait for \n */
+    (void) noecho();       /* don't print on getch() */
+    curs_set(2);
+
+    if (has_colors()) { 
+        setup_colors();
+    }
+
+    WINDOW *canvas_win = create_canvas_win();
+    WINDOW *status_win = create_status_win();
+
+    // Enable keyboard mapping
+    keypad(canvas_win, TRUE);
+    keypad(status_win, TRUE);
+
+    Cursor *cursor = cursor_new();
+
+    char test_msg[] = "Test mode";
+    print_status(test_msg, status_win);
+
+    wrefresh(status_win);
+
+    //// Main loop
+    int last_arrow_direction = KEY_RIGHT;
+    int ch;
+    while ((ch = wgetch(canvas_win)))
+    {
+        if ((ch == KEY_LEFT) || (ch == KEY_RIGHT) || (ch == KEY_UP) || (ch == KEY_DOWN)) {
+            cursor_key_to_move(ch, cursor);
+            last_arrow_direction = ch;
+        } else {
+            if (' ' <= ch && ch <= '~') {  // check if ch is printable
+                mvwaddch(canvas_win, cursor_y_to_canvas(cursor), cursor_x_to_canvas(cursor), ch);
+                cursor_key_to_move(last_arrow_direction, cursor);
+            } else {
+                // Print non-print characters to bottom left in status_win bar
+                mvwaddch(status_win, 0, COLS-3, ch); 
+            }
+        }
+        // Move UI cursor to the right place
+        wmove(canvas_win, cursor_y_to_canvas(cursor), cursor_x_to_canvas(cursor));
+
+        wrefresh(status_win);
+        wrefresh(canvas_win); // Refresh Canvas last so it gets the cursor
+    }
+
+    // Cleanup
+    cursor_free(cursor);
+    destroy_win(status_win);
+    destroy_win(canvas_win);
+    finish(0);
+}
+
+static void setup_colors() {
+    start_color();
+
+    // TODO: Use #define to get colors for standard uses
+    // Assign color codes
+    init_pair(1, COLOR_RED,     COLOR_BLACK);
+    init_pair(2, COLOR_GREEN,   COLOR_BLACK);
+    init_pair(3, COLOR_BLUE,    COLOR_BLACK);
+    init_pair(4, COLOR_CYAN,    COLOR_BLACK);
+    init_pair(5, COLOR_MAGENTA, COLOR_BLACK);
+    init_pair(6, COLOR_YELLOW,  COLOR_BLACK);
+    init_pair(7, COLOR_BLACK,   COLOR_WHITE);
+}
+
+WINDOW *create_newwin(int height, int width, int starty, int startx, int should_draw_box) {
+	WINDOW *local_win;
+
+	local_win = newwin(height, width, starty, startx);
+
+    if (should_draw_box) {
+        box(local_win, 0 , 0);		/* 0, 0 gives default characters 
+                                    * for the vertical and horizontal
+                                    * lines			*/
+        wrefresh(local_win);		/* Show that box 		*/
+
+    }
+
+	return local_win;
+}
+
+WINDOW *create_canvas_win() {
+	WINDOW *local_win;
+
+    //                                        + 1 due to bottom border
+	local_win = newwin(LINES - (STATUS_HEIGHT + 1), COLS, 0, 0);  // height, width, starty, startx
+
+    wborder(local_win, ACS_VLINE, ACS_VLINE, ACS_HLINE, ACS_HLINE,      // Sides:   ls,  rs,  ts,  bs,
+                       ACS_ULCORNER, ACS_URCORNER, ACS_LTEE, ACS_RTEE); // Corners: tl,  tr,  bl,  br
+
+    wrefresh(local_win);
+	return local_win;
+}
+
+WINDOW *create_status_win() {
+	WINDOW *local_win;
+    //                               + 2 due to horizontal borders
+	local_win = newwin(STATUS_HEIGHT + 2, COLS, 
+                        LINES - (STATUS_HEIGHT+2), 0);
+
+    wborder(local_win, ACS_VLINE, ACS_VLINE, ACS_HLINE, ACS_HLINE,      // Sides:   ls,  rs,  ts,  bs,
+                       ACS_LTEE, ACS_RTEE, ACS_LLCORNER, ACS_LRCORNER); // Corners: tl,  tr,  bl,  br
+
+    wrefresh(local_win);
+	return local_win;
+}
+
+void destroy_win(WINDOW *local_win)
+{	
+	// Clear borders explicitly
+    wborder(local_win, ' ', ' ', ' ',' ',' ',' ',' ',' ');
+
+	wrefresh(local_win);
+	delwin(local_win);
+}
+
+int print_status(char* str, WINDOW* window) {
+    wattrset(window, COLOR_PAIR(7));
+    return mvwprintw(window, 1, 1, str);
+}
+
+static void finish(int sig) {
+    endwin();
+
+    /* do your non-curses wrapup here */
+
+    exit(0);
+}

src/frontend.h

@@ -0,0 +1,11 @@
+#include <curses.h>
+
+static void finish(int sig);
+static void setup_colors();
+WINDOW *create_canvas_win();
+WINDOW *create_status_win();
+void destroy_win();
+
+int print_status(char* str, WINDOW* window);
+
+WINDOW *create_newwin(int height, int width, int starty, int startx, int should_draw_box);