From add17d025733bb70e05359604c8369d718488032 Mon Sep 17 00:00:00 2001
From: Christophe Meneboeuf <christophe@xtof.photo>
Date: Thu, 15 Sep 2016 23:43:00 +0200
Subject: [PATCH] Adding the state machine

---
 gol_apple2.c | 133 +++++++++++++++++++++++++++++++++++----------------
 1 file changed, 91 insertions(+), 42 deletions(-)

diff --git a/gol_apple2.c b/gol_apple2.c
index 2ab2b3c..80b360a 100755
--- a/gol_apple2.c
+++ b/gol_apple2.c
@@ -9,8 +9,9 @@
 
 /******************* FUNCTION DEFINITIONS **************/
 
-void init_display( void );                  /* Inits displayed playfield */
-void draw_cells( void );                    /* lets the user draw some starting cells */
+void init_display( void );              /* Inits displayed playfield */
+void draw_cells( void );                /* Draws the actual cells */
+void editor( void );                    /* lets the user draw some starting cells */
 uint8_t toggle_cell( const uint8_t x, const uint8_t y ); /* toggles the cell at the given coordinates. \
                                                             Returns the cursor X position */
 
@@ -28,15 +29,24 @@ const uint8_t JUMP_BEGINNING_NEXT_LINE = NB_LINES - 2u;
 
 #define ALIVE       1u
 #define DEAD        0u
-#define SPRITE_ALIVE       '0'
-#define SPRITE_DEAD        ' '
+#define SPRITE_ALIVE    '0'
+#define SPRITE_DEAD     ' '
+
+#define STATE_INIT      0u
+#define STATE_EDITOR    1u
+#define STATE_RUN       2u
+#define STATE_QUIT      3u
+uint8_t State = STATE_INIT;
+
+#define NO_KEY     '\0'
+char KeyPressed = NO_KEY;
 
 
 /******************* STATIC GLOBAL VARIABLES ******************/
 
 uint8_t Cells[ NB_COLUMNS ][ NB_LINES ];
 uint8_t Cells_Future[ NB_COLUMNS ][ NB_LINES ];
-
+uint8_t Cells_Initial[ NB_COLUMNS ][ NB_LINES ];
 
 /******************** CODE ************************/
 
@@ -46,15 +56,37 @@ int main( int argc, char** argv )
     (void)argc;
     (void)argv;
 
-    printf("HELLO");
-
-    /* Initial state */
-    memset( Cells, DEAD, sizeof(Cells) );
-    init_display();
-
-    /* go */
-    draw_cells();
-    run();
+    /* Running the state machine */
+    while( State != STATE_QUIT )
+    {
+        switch (State) {
+            case STATE_INIT:
+                memset( Cells, DEAD, sizeof(Cells) );
+                init_display();
+                State = STATE_EDITOR;
+                break;
+            case STATE_EDITOR:
+                editor();
+                State = STATE_RUN;
+                break;
+            case STATE_RUN:
+                run();
+                if( KeyPressed == 'e' ) { /* Go back to editor */
+                    State = STATE_EDITOR;
+                } else if( KeyPressed == 'r' ) { /* reset and rerun */
+                    memcpy( Cells, Cells_Initial, sizeof(Cells) );
+                    memcpy( Cells_Future, Cells_Initial, sizeof(Cells_Future) );
+                    draw_cells();
+                } else if( KeyPressed == 'q' ) { /* quit */
+                    State = STATE_QUIT;
+                }
+                break;
+            default: 
+                printf("ERROR!");
+                State = STATE_QUIT;
+                break;
+        }
+    }
 
     quit();
     return 0;
@@ -83,7 +115,24 @@ void init_display( void )
     cputcxy ( NB_COLUMNS-1u, NB_LINES-1u,'+');
 }
 
-void draw_cells( void )
+
+void draw_cells( void ) {
+    uint8_t x, y;
+    for( x = 1u; x < NB_COLUMNS - 1u; ++x )
+    {
+        for( y = 1u; y < NB_LINES - 1u; ++y )
+        {
+            if( Cells[x][y] == ALIVE ) {
+                cputcxy ( x, y, SPRITE_ALIVE );
+            } else {
+                cputcxy ( x, y, SPRITE_DEAD );
+            }
+        }
+    } 
+}
+
+
+void editor( void )
 {
     #define KEY_LEFT    'j'
     #define KEY_DOWN    'k'
@@ -91,7 +140,6 @@ void draw_cells( void )
     #define KEY_RIGHT   'l'
 
     uint8_t quit = 0;
-    uint8_t ch;
 
     uint8_t x = NB_COLUMNS >> 1u;
     uint8_t y = NB_LINES >> 1u;
@@ -99,33 +147,33 @@ void draw_cells( void )
 
     while ( quit == 0)
     {
-    cursor(1);
-    ch = cgetc();
-    switch (ch) {
-    case KEY_LEFT:
-            if( x > 1u ) { gotoxy( --x, y ); }
-      break;
-    case KEY_DOWN:
-            if( y < NB_LINES-2u ) { gotoxy( x, ++y ); }
-      break;
-    case KEY_UP:
-            if( y > 1u ) { gotoxy( x, --y ); }
-      break;
-    case KEY_RIGHT:
-            if( x < NB_COLUMNS-2u ) {	gotoxy( ++x, y ); }
-      break;
-    case ' ':
-            x = toggle_cell( x, y );
-            break;
-    case 'q':
-      quit = 1;
-      break;
-    }
+        cursor(1);
+        KeyPressed = cgetc();
+        switch (KeyPressed) {
+        case KEY_LEFT:
+                if( x > 1u ) { gotoxy( --x, y ); }
+          break;
+        case KEY_DOWN:
+                if( y < NB_LINES-2u ) { gotoxy( x, ++y ); }
+          break;
+        case KEY_UP:
+                if( y > 1u ) { gotoxy( x, --y ); }
+          break;
+        case KEY_RIGHT:
+                if( x < NB_COLUMNS-2u ) {	gotoxy( ++x, y ); }
+          break;
+        case ' ':
+                x = toggle_cell( x, y );
+                break;
+        case 'q':
+          quit = 1;
+          break;
+        }
 	}
 
     /* Cells was updated by the calls to toggle() */
     memcpy( Cells_Future, Cells, sizeof(Cells_Future) );
-
+    memcpy( Cells_Initial, Cells, sizeof(Cells_Initial) );
 }
 
 
@@ -149,12 +197,12 @@ void run( void  )
 {
     char str_nb_iteration [5];
     uint16_t nb_iterations = 2u;
-    char ch = '\0';
+    KeyPressed = NO_KEY;
     cursor(0);
 
     gotoxy( 0u, NB_LINES );
     printf("Iteration: 1");
-    while( ch != 'q')
+    while( KeyPressed == NO_KEY)
     {
         /* Evolving the cells */
         update();
@@ -163,7 +211,8 @@ void run( void  )
         printf( itoa(nb_iterations++, str_nb_iteration, 10) );
         /* Testing key pressed */
         if( kbhit() ){
-            ch = cgetc();
+            KeyPressed = cgetc();
+            break;
         }
     }
 }