#include "../graphics.c"

b8 button_0_down    = 0;
b8 button_1_down    = 0;
b8 button_1_checked = 0;

i64        text_len  = 0;
static c32 text[512] = {0};

i64 cursor    = 0;
i64 selection = 0;

void update_and_render_frame(void) {
  p_wait_events();

  for (i32 j = 0; j < g_platform.frame_height; ++j)
    for (i32 i = 0; i < g_platform.frame_width; ++i)
      g_platform.pixels[j * g_platform.frame_width + i] = (vec3_f32) { .2f, .1f, 0.f };

  if (g_platform.cursor_x >= 40 && g_platform.cursor_x < 100 && g_platform.cursor_y >= 40 && g_platform.cursor_y < 100) {
    button_0_down = g_platform.key_down[BUTTON_LEFT];
    if (button_0_down)
      fill_rectangle(OP_SET, (vec3_f32) { 1.f, 1.f, 1.f }, 40, 40, 60, 60);
    else
      fill_rectangle(OP_SET, (vec3_f32) { 0.f, 1.f, 0.f }, 40, 40, 60, 60);
  } else {
    button_0_down = 0;
    fill_rectangle(OP_SET, (vec3_f32) { .1f, .5f, .1f }, 40, 40, 60, 60);
  }

  if (g_platform.cursor_x >= 40 && g_platform.cursor_x < 100 && g_platform.cursor_y >= 120 && g_platform.cursor_y < 180) {
    button_1_down = g_platform.key_down[BUTTON_LEFT];
    if (g_platform.key_pressed[BUTTON_LEFT])
      button_1_checked = !button_1_checked;
    if (button_1_down)
      fill_rectangle(OP_SET, (vec3_f32) { 1.f, 1.f, 1.f }, 40, 120, 60, 60);
    else if (button_1_checked)
      fill_rectangle(OP_SET, (vec3_f32) { 1.f, .5f, .5f }, 40, 120, 60, 60);
    else
      fill_rectangle(OP_SET, (vec3_f32) { .5f, 1.f, .5f }, 40, 120, 60, 60);
  } else {
    button_1_down = 0;
    if (button_1_checked)
      fill_rectangle(OP_SET, (vec3_f32) { 1.f, 0.f, 0.f }, 40, 120, 60, 60);
    else
      fill_rectangle(OP_SET, (vec3_f32) { 0.f, 1.f, 0.f }, 40, 120, 60, 60);
  }

  i64 w  = g_platform.frame_width  / 2;
  i64 h  = g_platform.frame_height / 2;
  i64 x0 = w / 2;
  i64 y0 = h / 2;

  vec3_f32 color = { 1.f, .5f, .5f };

  if (g_platform.cursor_x >= x0 && g_platform.cursor_x < x0 + w &&
      g_platform.cursor_y >= y0 && g_platform.cursor_y < y0 + h)
    color = (vec3_f32) { 1.f, 1.f, 1.f };

  for (i64 i = 0; i < g_platform.input_size; ++i)
    if (g_platform.input[i].ctrl)
      switch (g_platform.input[i].key) {
        case KEY_V: {
          if (selection != 0) {
            i64 i0 = selection < 0 ? cursor + selection : cursor;
            i64 i1 = selection < 0 ? cursor : cursor + selection;
            for (i64 i = 0; i1 + i < text_len; ++i)
              text[i0 + i] = text[i1 + i];
            selection = 0;
            cursor    = i0;
            text_len -= i1 - i0;
          }

          for (i64 n = 0; n < g_platform.clipboard_size;) {
            c32 c = utf8_read(g_platform.clipboard_size - n, g_platform.clipboard + n);

            if (text_len < (i64) (sizeof text / sizeof *text)) {
              for (i64 j = text_len; j > cursor; --j)
                text[j] = text[j - 1];
              text[cursor++] = c;
              ++text_len;
            }

            n += utf8_size(c);
          }
        } break;

        case KEY_X: {
          i64       len = 0;
          static c8 buf[1024];

          i64 i0 = selection < 0 ? cursor + selection : cursor;
          i64 i1 = selection < 0 ? cursor : cursor + selection;
          for (i64 i = 0; len + 4 <= (i64) sizeof buf && i < i1 - i0; ++i)
            len += utf8_write(text[i0 + i], buf + len);

          if (len > 0)
            p_clipboard_write(len, buf);

          for (i64 i = 0; i1 + i < text_len; ++i)
            text[i0 + i] = text[i1 + i];
          selection = 0;
          cursor    = i0;
          text_len -= i1 - i0;
        } break;

        case KEY_C: {
          i64       len = 0;
          static c8 buf[1024];

          i64 i0 = selection < 0 ? cursor + selection : cursor;
          i64 i1 = selection < 0 ? cursor : cursor + selection;
          for (i64 i = 0; len + 4 <= (i64) sizeof buf && i < i1 - i0; ++i)
            len += utf8_write(text[i0 + i], buf + len);

          if (len > 0)
            p_clipboard_write(len, buf);
        } break;

        default:;
      }
    else
      switch (g_platform.input[i].key) {
        case KEY_LEFT:
          if (g_platform.key_down[MOD_SHIFT]) {
            if (cursor > 0)
              ++selection;
          } else if (selection != 0) {
            cursor = selection < 0 ? cursor + selection + 1 : cursor + 1;
            selection = 0;
          }
          if (cursor > 0)
            --cursor;
          break;

        case KEY_RIGHT:
          if (g_platform.key_down[MOD_SHIFT]) {
            if (cursor < text_len)
              --selection;
          } else if (selection != 0) {
            cursor = selection < 0 ? cursor - 1 : cursor + selection - 1;
            selection = 0;
          }
          if (cursor < text_len)
            ++cursor;
          break;

        case KEY_BACKSPACE:
          if (selection != 0) {
            i64 i0 = selection < 0 ? cursor + selection : cursor;
            i64 i1 = selection < 0 ? cursor : cursor + selection;
            for (i64 i = 0; i1 + i < text_len; ++i)
              text[i0 + i] = text[i1 + i];
            selection = 0;
            cursor    = i0;
            text_len -= i1 - i0;
          } else if (cursor > 0 && text_len > 0) {
            for (i64 i = cursor; i < text_len; ++i)
              text[i - 1] = text[i];
            --cursor;
            --text_len;
          }
          break;

        case KEY_DELETE:
          if (selection != 0) {
            i64 i0 = selection < 0 ? cursor + selection : cursor;
            i64 i1 = selection < 0 ? cursor : cursor + selection;
            for (i64 i = 0; i1 + i < text_len; ++i)
              text[i0 + i] = text[i1 + i];
            selection = 0;
            cursor    = i0;
            text_len -= i1 - i0;
          } else if (cursor < text_len) {
            for (i64 i = cursor + 1; i < text_len; ++i)
              text[i - 1] = text[i];
            --text_len;
          }
          break;

        case KEY_ENTER:
        case KEY_TAB:
          g_platform.input[i].c = g_platform.input[i].key;
          //  fallthrough

        default:
          if (g_platform.input[i].c) {
            if (selection != 0) {
              i64 i0 = selection < 0 ? cursor + selection : cursor;
              i64 i1 = selection < 0 ? cursor : cursor + selection;
              for (i64 i = 0; i1 + i < text_len; ++i)
                text[i0 + i] = text[i1 + i];
              selection = 0;
              cursor    = i0;
              text_len -= i1 - i0;
            }

            if (text_len < (i64) (sizeof text / sizeof *text)) {
              for (i64 i = text_len; i > cursor; --i)
                text[i] = text[i - 1];
              text[cursor++] = g_platform.input[i].c;
              ++text_len;
            }
          }
      }

  draw_text_area((vec3_f32) {0}, x0 + 8, y0 - 8, w, h, 10., 10., text_len, text);
  draw_text_area(color, x0, y0, w, h, 10., 10., text_len, text);
  draw_selection_cursor((vec3_f32) { 1.f, 1.f, 1.f }, x0, y0, w, h, 10., 10., cursor, selection, text_len, text);

  p_render_frame();
}

i32 main(i32 argc, c8 **argv) {
  (void) argc;
  (void) argv;

  g_platform = (Platform) {
    .title            = "UI",
    .frame_width      = 960,
    .frame_height     = 720,
    .exact_resolution = 1,
  };

  p_event_loop();

  return 0;
}