Add ROM selection menu

src/linux/port.c

@@ -3,6 +3,7 @@
 
 #include <time.h>
 #include <unistd.h>
+#include <dirent.h>
 
 #include <sys/mman.h>
 #include <sys/stat.h>
@@ -97,6 +98,62 @@ typedef struct {
 } platform_data;
 
 
+/* Directories */
+
+static int cmp_files(const void* _a, const void* _b) {
+    const char* a = *(const char**)_a;
+    const char* b = *(const char**)_b;
+
+    int diff = 0;
+    for (char ca = 1, cb = 1; ca && cb && 0 == diff; ++a, ++b) {
+        // Cut extensions; replace underscore with space
+        ca = (*a == '_' ? ' ' : (*a == '.' ? '\0' : *a));
+        cb = (*b == '_' ? ' ' : (*b == '.' ? '\0' : *b));
+        diff = (ca - cb);
+    }
+
+    return diff;
+}
+
+static int count_files(DIR* dir) {
+    int count = 0;
+    struct dirent* de = NULL;
+    while (NULL != (de = readdir(dir))) {
+        if ('.' != de->d_name[0]) ++count;
+    }
+    rewinddir(dir);
+    return count;
+}
+
+static void make_file_list(DIR* dir, File_List* files) {
+    files->count = count_files(dir);
+    files->files = calloc(files->count, sizeof(char*));
+    struct dirent* de = NULL;
+    int i_file = 0;
+    while (NULL != (de = readdir(dir))) {
+        if ('.' != de->d_name[0]) {
+            files->files[i_file] = strdup(de->d_name);
+            ++i_file;
+        }
+    }
+    qsort(files->files, files->count, sizeof(char*), cmp_files);
+}
+
+static void free_file_list(File_List* files) {
+    for (int i = 0; i < files->count; ++i) {
+        free(files->files[i]);
+    }
+    free(files->files);
+}
+
+static int find_file(File_List* files, const char* filename) {
+    int i = (files->count - 1);
+    for ( ; i >= 0 &&
+            (0 != strcmp(files->files[i], filename)); --i);
+    return i;
+}
+
+
 /* Input */
 
 static const int sdl_action_keycodes[Action_Max] = {
@@ -175,13 +232,6 @@ static nese_Action process_events(nes* sys) {
     return action;
 }
 
-nese_Action nese_update_input(void* plat_data, nes_Input* input) {
-    platform_data* plat = (platform_data*)plat_data;
-    nese_Action action = process_events(plat->sys);
-    if (NULL != input) *input = plat->sys->core.memory.input;
-    return action;
-}
-
 
 /*
  * Time / Video - Should be maximally reusable across platforms
@@ -385,6 +435,59 @@ int nese_get_audio_frequency(void*) {
 // TODO: Audio functions
 
 
+/* Menus */
+
+nese_Action nese_update_input(void* plat_data, nes_Input* input) {
+    time_sleep_until(time_now() + (NS_PER_S / 60));
+    platform_data* plat = (platform_data*)plat_data;
+    nese_Action action = process_events(plat->sys);
+    if (NULL != input) *input = plat->sys->core.memory.input;
+    return action;
+}
+
+static nese_Action run_rom_menu(platform_data* plat, Menu_State* state,
+                                char* filename, int sz_filename) {
+    nese_Action action = Action_Cancel;
+
+    DIR* dir = opendir("rom");
+
+    if (NULL == dir) {
+        modal_popup(plat, "No ROMS found!\nPress any key to exit",
+                    color_error);
+
+    } else {
+        File_List files = {0};
+        make_file_list(dir, &files);
+        closedir(dir);
+
+        Menu_State menu = {0};
+        if (NULL != state) menu = *state;
+
+        // Add 4 to skip past "rom/"
+        int current = find_file(&files, filename + 4);
+        if (current >= 0) menu.cursor = current;
+
+        action = run_menu(plat, &menu, &files, 20);
+
+        if (Action_OK == action) {
+            if (    menu.cursor >= 0 &&
+                    menu.cursor < files.count) {
+                snprintf(filename, sz_filename - 1,
+                         "%s/%s", "rom", files.files[menu.cursor]);
+            } else {
+                action = Action_Cancel;
+            }
+        }
+
+        free_file_list(&files);
+
+        if (NULL != state) *state = menu;
+    }
+
+    return action;
+}
+
+
 /* Platform Data */
 
 static int plat_init(platform_data* plat) {
@@ -414,6 +517,7 @@ static nes sys = {0};
 
 int main(int argc, char* argv[]) {
     int status = 0;
+    char filename[1024] = {0};
 
     // This should be tiny enough to keep on the stack.
     platform_data plat = {
@@ -425,22 +529,27 @@ int main(int argc, char* argv[]) {
     }
 
     if (0 == status) {
-        if (argc <= 1) {
-            modal_popup(&plat, "No ROM file provided.", color_error);
-            status = -1;
+        if (1 < argc) {
+            strncpy(filename, argv[1], sizeof(filename) - 1);
+            filename[sizeof(filename) - 1] = '\0';
+        }
 
-        } else {
-            status = load_cart(&plat.cart, argv[1], &sys);
-            if (0 != status) {
-                char message[128];
-                snprintf(message, sizeof(message), "Failed to load %s", argv[1]);
-                modal_popup(&plat, message, color_error);
+        while (NULL == sys.cart_header && 0 == status) {
+            if (filename[0]) {
+                status = load_cart(&plat.cart, filename, &sys);
+                if (0 != status) {
+                    char message[1039];
+                    snprintf(message, sizeof(message),
+                             "Failed to load %s", filename);
+                    modal_popup(&plat, message, color_error);
+                }
             }
-        }
 
-        if (NULL == sys.cart_header) {
-            // TODO: ROM selection menu
-            status = -1;
+            if (NULL == sys.cart_header) {
+                nese_Action action = run_rom_menu(&plat, NULL,
+                                                  filename, sizeof(filename));
+                status = (Action_OK == action) ? 0 : -1;
+            }
         }
 
         // This shall invoke menus as needed

src/menu.c

@@ -2,6 +2,7 @@
 #include "nes.h"
 #include "action.h"
 #include "port.h"
+#include "draw.h"
 
 
 static nese_Action wait_for_input(void* plat, uint8_t* new_buttons) {
@@ -22,7 +23,7 @@ static nese_Action wait_for_input(void* plat, uint8_t* new_buttons) {
 }
 
 
-int modal_popup(void* plat, const char* message, uint32_t color) {
+nese_Action modal_popup(void* plat, const char* message, uint32_t color) {
     int w = 0;
     int h = 0;
 
@@ -45,3 +46,119 @@ int modal_popup(void* plat, const char* message, uint32_t color) {
 
     return action;
 }
+
+static void fix_filename(char* dst, int n, const char* src) {
+    for (   int i = 0;
+            i < n && *src && '.' != *src;
+            ++i, ++dst, ++src) {
+        *dst = ('_' == *src ? ' ' : *src);
+    }
+    *dst = '\0';
+}
+
+static inline int n_visible(void) {
+    return ((nes_ppu_render_h - 20) / 11);
+}
+
+static const uint32_t menu_colors[6] = {
+    color_red, color_orange, color_yellow,
+    color_green, color_blue, color_purple,
+};
+
+static void show_menu(void* plat, const Menu_State* menu,
+                      const File_List* files, int x) {
+    nese_draw_begin(plat);
+
+    int bottom = menu->top + n_visible() - 1;
+
+    int max = n_visible();
+    if (max > files->count) max = files->count;
+    int y = (nes_ppu_render_h - (max * 11)) / 2;
+
+    for (   int n = menu->top;
+            n < files->count && n <= bottom;
+            ++n, y += 11 ) {
+        char filename[100];
+        fix_filename(filename, sizeof(filename) - 1,
+                     files->files[n]);
+        nese_draw_text(
+                plat,
+                ( (menu->top == n && 0 != menu->top) ||
+                  (bottom == n && files->count - 1 > bottom) ) ?
+                  "..." : filename,
+                x, y,
+                (menu->cursor == n) ?
+                    color_white : menu_colors[n % 6]
+            );
+        if (menu->cursor == n) {
+            nese_draw_text(plat, ">", x - 10, y, color_white);
+        }
+    }
+
+    nese_draw_finish(plat);
+}
+
+int run_menu(void* plat, Menu_State* state, const File_List* files, int x) {
+    Menu_State menu = {0};
+    if (NULL != state) {
+        menu = *state;
+        if (menu.cursor < 0) {
+            menu.cursor = 0;
+        } else if (menu.cursor >= files->count) {
+            menu.cursor = files->count - 1;
+        }
+    }
+
+    nese_Action action = Action_OK;
+    while (Action_OK == action) {
+        // Scrolling (do this first to ensure menu is valid)
+        const int visible = n_visible() - 1;
+        menu.top = menu.cursor - (visible / 2);
+        if (menu.top <= 0) {
+            // We use <= so we don't readjust the top from 0
+            menu.top = 0;
+        } else if (menu.top + visible >= files->count) {
+            menu.top = (files->count - 1) - visible;
+        }
+
+        show_menu(plat, &menu, files, x);
+
+        uint8_t buttons = 0;
+        action = wait_for_input(plat, &buttons);
+
+        if (Action_Menu == action) {
+            action = Action_Cancel;
+
+        } else if (Action_OK == action) {
+            if (buttons & (1 << Button_B)) {
+                action = Action_Cancel;
+                break;
+
+            } else if (buttons & ( (1 << Button_A) |
+                            (1 << Button_Start) )) {
+                // Select
+                break;
+
+            } else if (buttons & (1 << Button_Up)) {
+                if (menu.cursor > 0) --menu.cursor;
+
+            } else if (buttons & (  (1 << Button_Down) |
+                                    (1 << Button_Select) )) {
+                if (menu.cursor < (files->count - 1)) {
+                    ++menu.cursor;
+                } else if (buttons & (1 << Button_Select)) {
+                    // Wrap around on Select
+                    menu.cursor = 0;
+                }
+            }
+
+        } else if (Action_Quit != action && Action_Cancel != action) {
+            // Ignore anything that isn't "Menu", "Cancel" or "Quit"
+            action = Action_OK;
+        }
+    }
+
+    if (NULL != state) *state = menu;
+
+    return action;
+}

src/menu.h

@@ -2,6 +2,7 @@
 #define NESE_MENU_H_
 
 #include "cartinfo.h"
+#include "action.h"
 
 
 typedef struct {
@@ -9,12 +10,14 @@ typedef struct {
 	int top;
 } Menu_State;
 
+typedef struct {
+    int count;
+    char** files;
+} File_List;
 
-int run_rom_menu(void*, Menu_State*, const Cart_Info*, char* file, int sz_file);
-
-int run_game_menu(void*, Menu_State*);
+nese_Action run_menu(void*, Menu_State* state, const File_List* files, int x);
 
-int modal_popup(void*, const char* message, uint32_t color);
+nese_Action modal_popup(void*, const char* message, uint32_t color);
 
 
 #endif // NESE_MENU_H_