2 files changed, 211 insertions(+), 0 deletions(-)

A text-viewer/include/gui_component_text_view.h
A text-viewer/src/gui_component_text_view.c

@@ 0,0 1,33 @@
+#ifndef __GUI_COMPONENT_TEXT_VIEW_H__
+#define __GUI_COMPONENT_TEXT_VIEW_H__
+
+#include "display_utils.h"
+#include "gui.h"
+
+typedef struct {
+  char *line;
+  uint16_t length;
+} line_t;
+
+typedef struct {
+  line_t *lines;
+  uint16_t lines_count;
+  char *text;
+  font_t *font;
+  display_pixel_t color;
+} multiline_text_t;
+
+multiline_text_t *gui_multiline_text_create(font_t *font, display_pixel_t color, char *text);
+
+component_t gui_text_view_create(gui_t *gui, multiline_text_t *text, int16_t x, int16_t y);
+void gui_text_view_register_commands(gui_t *gui, component_t *text_view);
+
+void gui_text_view_scroll(component_t *text_view, int16_t x, int16_t y);
+void gui_text_view_reset_scroll(component_t *text_view);
+
+void gui_text_view_render(container_t *container, component_t *component,
+                          gui_t *gui);
+void gui_text_view_update(container_t *container, component_t *component,
+                          gui_t *gui);
+
+#endif // __GUI_COMPONENT_TEXT_VIEW_H__

@@ 0,0 1,178 @@
+#include "gui_component_text_view.h"
+#include "display_utils.h"
+#include "input.h"
+#include "renderer.h"
+#include <string.h>
+#include <stdlib.h>
+#include "direction.h"
+#include "keyboard_const.h"
+#include "rotation_const.h"
+
+multiline_text_t *gui_multiline_text_create(font_t *font, display_pixel_t color, char *text) {
+  size_t len = strlen(text) + 1;
+  size_t lines = 1;
+
+  for (int i = 0; i < len; i++) {
+    if (text[i] == '\n') {
+      lines++;
+    }
+  }
+
+  void* new = realloc(text, len + sizeof(multiline_text_t) + sizeof(line_t) * lines);
+  if (new == NULL) {
+    free(text);
+    return NULL;
+  }
+
+  text = new;
+
+  multiline_text_t *multiline_text = (multiline_text_t*)(new + len);
+  line_t *line_ptr = (line_t*)(new + len + sizeof(multiline_text_t));
+
+  multiline_text->font = font;
+  multiline_text->color = color;
+  multiline_text->lines = line_ptr;
+  multiline_text->lines_count = lines;
+  multiline_text->text = text;
+
+  bool new_line = false;
+  uint32_t line_index = 0;
+  uint32_t line_length = 0;
+  char *line_str_ptr = text;
+
+  for (int i = 0; i < len; i++) {
+    if (new_line) {
+      line_ptr[line_index].line = line_str_ptr;
+      line_ptr[line_index++].length = line_length;
+      line_str_ptr += line_length + 1;
+      line_length = 0;
+      new_line = false;
+    }
+
+    if (text[i] == '\n') {
+      text[i] = '\0';
+      new_line = true;
+    } else {
+      line_length++;
+    }
+  }
+
+  if (line_index < lines) {
+    line_ptr[line_index].line = line_str_ptr;
+    line_ptr[line_index].length = line_length;
+  }
+
+  return multiline_text;
+}
+
+static void command_handler_move(void *state, direction_t direction, int amount) {
+  component_t *text_view = (component_t*)state;
+  if (text_view->focused) {
+    direction_move_xy(direction, (int32_t*)&text_view->x, (int32_t*)&text_view->y, -amount);
+  }
+}
+
+static void command_handler_move_down(void *state, int amount) {
+  command_handler_move(state, DOWN, amount);
+}
+
+static void command_handler_move_up(void *state, int amount) {
+  command_handler_move(state, UP, amount);
+}
+
+static void command_handler_move_left(void *state, int amount) {
+  command_handler_move(state, LEFT, amount);
+}
+static void command_handler_move_right(void *state, int amount) {
+  command_handler_move(state, RIGHT, amount);
+}
+static void command_handler_reset(void *state, int amount) {
+  gui_text_view_reset_scroll((component_t*)state);
+}
+
+component_t gui_text_view_create(gui_t *gui, multiline_text_t *text, int16_t x, int16_t y) {
+  component_t text_view =
+      gui_component_create(x, y, 1, 1, gui_text_view_render, gui_text_view_update);
+  text_view.state = text;
+  text_view.focusable = true;
+
+  return text_view;
+}
+
+void gui_text_view_register_commands(gui_t *gui, component_t *text_view) {
+  commands_register(gui->commands, IN_KEYBOARD, KEYBOARD_LEFT,
+                    command_handler_move_left, text_view);
+  commands_register(gui->commands, IN_KEYBOARD, KEYBOARD_RIGHT,
+                    command_handler_move_right, text_view);
+  commands_register(gui->commands, IN_KEYBOARD, KEYBOARD_DOWN,
+                    command_handler_move_down, text_view);
+  commands_register(gui->commands, IN_KEYBOARD, KEYBOARD_UP,
+                    command_handler_move_up, text_view);
+  commands_register(gui->commands, IN_KEYBOARD, 'r',
+                    command_handler_reset, text_view);
+
+  commands_register(gui->commands, IN_ENCODER_ROTATE,
+                    ROTATION_ENCODER_HORIZONTAL, command_handler_move_right,
+                    text_view);
+
+  commands_register(gui->commands, IN_ENCODER_ROTATE,
+                    ROTATION_ENCODER_VERTICAL, command_handler_move_down,
+                    text_view);
+
+  commands_register(gui->commands, IN_ENCODER_CLICK,
+                    ROTATION_ENCODER_ZOOM, command_handler_reset,
+                    text_view);
+}
+
+void gui_text_view_scroll(component_t *text_view, int16_t x, int16_t y) {
+  text_view->x -= x;
+  text_view->y -= y;
+}
+
+void gui_text_view_reset_scroll(component_t *text_view) {
+  text_view->x = 0;
+  text_view->y = 0;
+}
+
+void gui_text_view_render(container_t *container, component_t *component,
+                          gui_t *gui) {
+  multiline_text_t *text = (multiline_text_t*)component->state;
+  font_t *font = text->font;
+  int16_t x_offset = component->x, y_offset = component->y;
+
+  if (x_offset > 0) {
+    x_offset = 0;
+  }
+
+  if (y_offset > 0) {
+    y_offset = 0;
+  } else if (y_offset < -(font->size + font->line_spacing) * (text->lines_count) + gui->size.y - container->y) {
+    y_offset = -(font->size + font->line_spacing) * (text->lines_count) + gui->size.y - container->y;
+  }
+
+  component->x = x_offset;
+  component->y = y_offset;
+
+  int16_t first_line_index = -y_offset / (font->size + font->line_spacing);
+  int16_t lines_count = gui->size.y / font->size;
+  if (first_line_index < 0) {
+    first_line_index = 0;
+  }
+  int16_t last_line_index = lines_count + first_line_index;
+
+  y_offset += first_line_index * (font->size + font->line_spacing);
+
+  for (int i = first_line_index; i < last_line_index && i < text->lines_count;
+       i++) {
+    line_t *line = &text->lines[i];
+    size2d_t size = renderer_write_string(gui->renderer, x_offset, y_offset,
+                                          line->length, font, line->line, text->color);
+
+    y_offset += size.y;
+  }
+}
+
+void gui_text_view_update(container_t *container, component_t *component,
+                          gui_t *gui) {
+  // do nothing
+}