Add Text viewer (#87)

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## Description
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Adds a basic text viewer. It does not (yet) support full file content.
superseeds #21 

## Motivation and Context
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issue here -->
There were too many changes to merge from the original PR.

## How Has This Been Tested?
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On an SC64 via devcontainer.

## Screenshots
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## Types of changes
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- [x] Improvement (non-breaking change that adds a new feature)
- [ ] Bug fix (fixes an issue)
- [ ] Breaking change (breaking change)
- [ ] Config and build (change in the configuration and build system,
has no impact on code or features)

## Checklist:
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- [ ] My code follows the code style of this project.
- [ ] My change requires a change to the documentation.
- [ ] I have updated the documentation accordingly.
- [ ] I have added tests to cover my changes.
- [ ] All new and existing tests passed.

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Signed-off-by: GITHUB_USER <GITHUB_USER_EMAIL>

---------

Co-authored-by: Mateusz Faderewski <sc@mateuszfaderewski.pl>
Co-authored-by: Mateusz Faderewski <polprzewodnikowy@gmail.com>

Makefile

@@ -56,6 +56,7 @@ SRCS = \
 	menu/views/fault.c \
 	menu/views/file_info.c \
 	menu/views/image_viewer.c \
+	menu/views/text_viewer.c \
 	menu/views/load_disk.c \
 	menu/views/load_emulator.c \
 	menu/views/load_rom.c \

src/menu/menu.c

@@ -148,6 +148,7 @@ static view_t menu_views[] = {
     { MENU_MODE_FILE_INFO, view_file_info_init, view_file_info_display },
     { MENU_MODE_SYSTEM_INFO, view_system_info_init, view_system_info_display },
     { MENU_MODE_IMAGE_VIEWER, view_image_viewer_init, view_image_viewer_display },
+    { MENU_MODE_TEXT_VIEWER, view_text_viewer_init, view_text_viewer_display },
     { MENU_MODE_MUSIC_PLAYER, view_music_player_init, view_music_player_display },
     { MENU_MODE_CREDITS, view_credits_init, view_credits_display },
     { MENU_MODE_SETTINGS_EDITOR, view_settings_init, view_settings_display },

src/menu/menu_state.h

@@ -29,6 +29,7 @@ typedef enum {
     MENU_MODE_FILE_INFO,
     MENU_MODE_SYSTEM_INFO,
     MENU_MODE_IMAGE_VIEWER,
+    MENU_MODE_TEXT_VIEWER,
     MENU_MODE_MUSIC_PLAYER,
     MENU_MODE_CREDITS,
     MENU_MODE_SETTINGS_EDITOR,
@@ -50,6 +51,7 @@ typedef enum {
     ENTRY_TYPE_EMULATOR,
     ENTRY_TYPE_SAVE,
     ENTRY_TYPE_IMAGE,
+    ENTRY_TYPE_TEXT,
     ENTRY_TYPE_MUSIC,
     ENTRY_TYPE_OTHER,
 } entry_type_t;

src/menu/views/browser.c

@@ -14,6 +14,7 @@ static const char *disk_extensions[] = { "ndd", NULL };
 static const char *emulator_extensions[] = { "nes", "sfc", "smc", "gb", "gbc", "sms", "gg", "sg", NULL };
 static const char *save_extensions[] = { "sav", NULL }; // TODO: "eep", "sra", "srm", "fla" could be used if transfered from different flashcarts.
 static const char *image_extensions[] = { "png", NULL };
+static const char *text_extensions[] = { "txt", "ini", "yml", "yaml", NULL };
 static const char *music_extensions[] = { "mp3", NULL };
 
 
@@ -46,6 +47,10 @@ static int compare_entry (const void *pa, const void *pb) {
             return -1;
         } else if (b->type == ENTRY_TYPE_IMAGE) {
             return 1;
+        } else if (a->type == ENTRY_TYPE_TEXT) {
+            return -1;
+        } else if (b->type == ENTRY_TYPE_TEXT) {
+            return 1;
         } else if (a->type == ENTRY_TYPE_MUSIC) {
             return -1;
         } else if (b->type == ENTRY_TYPE_MUSIC) {
@@ -110,6 +115,8 @@ static bool load_directory (menu_t *menu) {
             entry->type = ENTRY_TYPE_SAVE;
         } else if (file_has_extensions(info.fname, image_extensions)) {
             entry->type = ENTRY_TYPE_IMAGE;
+        } else if (file_has_extensions(info.fname, text_extensions)) {
+            entry->type = ENTRY_TYPE_TEXT;
         } else if (file_has_extensions(info.fname, music_extensions)) {
             entry->type = ENTRY_TYPE_MUSIC;
         } else {
@@ -297,6 +304,9 @@ static void process (menu_t *menu) {
             case ENTRY_TYPE_IMAGE:
                 menu->next_mode = MENU_MODE_IMAGE_VIEWER;
                 break;
+            case ENTRY_TYPE_TEXT:
+                menu->next_mode = MENU_MODE_TEXT_VIEWER;
+                break;
             case ENTRY_TYPE_MUSIC:
                 menu->next_mode = MENU_MODE_MUSIC_PLAYER;
                 break;
@@ -334,6 +344,7 @@ static void draw (menu_t *menu, surface_t *d) {
             case ENTRY_TYPE_ROM: action = "A: Load"; break;
             case ENTRY_TYPE_DISK: action = "A: Load"; break;
             case ENTRY_TYPE_IMAGE: action = "A: Show"; break;
+            case ENTRY_TYPE_TEXT: action = "A: View"; break;
             case ENTRY_TYPE_MUSIC: action = "A: Play"; break;
             default: action = "A: Info"; break;
         }

src/menu/views/text_viewer.c

@@ -0,0 +1,78 @@
+#include <fatfs/ff.h>
+
+#include "utils/fs.h"
+#include "views.h"
+
+static char *file_content;
+
+static void process (menu_t *menu) {
+    if (menu->actions.back) {
+        menu->next_mode = MENU_MODE_BROWSER;
+    }
+}
+
+static void draw (menu_t *menu, surface_t *d) {
+    rdpq_attach(d, NULL);
+
+    component_background_draw();
+
+    component_layout_draw();
+
+	component_main_text_draw(
+        ALIGN_CENTER, VALIGN_TOP,
+        "TEXT VIEWER\n"
+        "\n"
+    );
+
+    component_main_text_draw(
+        ALIGN_LEFT, VALIGN_TOP,
+        "\n"
+        "\n"
+        "%s\n",
+        file_content
+    );
+
+
+    component_actions_bar_text_draw(
+        ALIGN_LEFT, VALIGN_TOP,
+        "\n"
+        "B: Back"
+    );
+
+    rdpq_detach_show();
+}
+
+
+void view_text_viewer_init (menu_t *menu) {
+    path_t *path = path_clone_push(menu->browser.directory, menu->browser.entry->name);
+
+    uint32_t file_size = file_get_size(path_get(path));
+
+    if (file_size > 1024) { // FIXME: this is just a placeholder until scrolling is implemented.
+        file_size = 1024; // For the moment, we just set it to that, since any more would be a waste.
+    }
+
+    file_content = calloc(file_size, 1);
+
+    // read file content
+    FIL fil;
+    UINT br;
+
+    if (f_open(&fil, strip_sd_prefix(path_get(path)), FA_READ) != FR_OK) {
+        debugf("Error loading file\n");
+    }
+    if (f_read(&fil, file_content, file_size, &br) != FR_OK) {
+        f_close(&fil);
+        debugf("Error loading file content\n");
+    }
+    if (f_close(&fil) != FR_OK) {
+        debugf("Error closing file\n");
+    }
+
+    path_free(path);
+}
+
+void view_text_viewer_display (menu_t *menu, surface_t *display) {
+    process(menu);
+    draw(menu, display);
+}

src/menu/views/views.h

@@ -32,6 +32,9 @@ void view_system_info_display (menu_t *menu, surface_t *display);
 void view_image_viewer_init (menu_t *menu);
 void view_image_viewer_display (menu_t *menu, surface_t *display);
 
+void view_text_viewer_init (menu_t *menu);
+void view_text_viewer_display (menu_t *menu, surface_t *display);
+
 void view_music_player_init (menu_t *menu);
 void view_music_player_display (menu_t *menu, surface_t *display);