/* SPDX-License-Identifier: GPL-2.0-or-later
 * Copyright 2019 Blender Foundation. All rights reserved. */

/** \file
 * \ingroup edanimation
 */

#include "BKE_context.h"
#include "BKE_scene.h"

#include "GPU_immediate.h"
#include "GPU_matrix.h"
#include "GPU_state.h"

#include "ED_time_scrub_ui.h"

#include "WM_api.h"
#include "WM_types.h"

#include "UI_interface.h"
#include "UI_interface_icons.h"
#include "UI_resources.h"
#include "UI_view2d.h"

#include "DNA_scene_types.h"

#include "BLI_math.h"
#include "BLI_rect.h"
#include "BLI_string.h"
#include "BLI_timecode.h"

#include "RNA_access.h"
#include "RNA_prototypes.h"

void ED_time_scrub_region_rect_get(const ARegion *region, rcti *rect)
{
  rect->xmin = 0;
  rect->xmax = region->winx;
  rect->ymax = region->winy;
  rect->ymin = rect->ymax - UI_TIME_SCRUB_MARGIN_Y;
}

static int get_centered_text_y(const rcti *rect)
{
  return BLI_rcti_cent_y(rect) - UI_DPI_FAC * 4;
}

static void draw_background(const rcti *rect)
{
  uint pos = GPU_vertformat_attr_add(immVertexFormat(), "pos", GPU_COMP_F32, 2, GPU_FETCH_FLOAT);
  immBindBuiltinProgram(GPU_SHADER_3D_UNIFORM_COLOR);

  immUniformThemeColor(TH_TIME_SCRUB_BACKGROUND);

  GPU_blend(GPU_BLEND_ALPHA);

  immRectf(pos, rect->xmin, rect->ymin, rect->xmax, rect->ymax);

  GPU_blend(GPU_BLEND_NONE);

  immUnbindProgram();
}

static void get_current_time_str(
    const Scene *scene, bool display_seconds, int frame, uint max_len, char *r_str)
{
  if (display_seconds) {
    BLI_timecode_string_from_time(r_str, max_len, 0, FRA2TIME(frame), FPS, U.timecode_style);
  }
  else {
    BLI_snprintf(r_str, max_len, "%d", frame);
  }
}

static void draw_current_frame(const Scene *scene,
                               bool display_seconds,
                               const View2D *v2d,
                               const rcti *scrub_region_rect,
                               int current_frame)
{
  const uiFontStyle *fstyle = UI_FSTYLE_WIDGET;
  int frame_x = UI_view2d_view_to_region_x(v2d, current_frame);

  char frame_str[64];
  get_current_time_str(scene, display_seconds, current_frame, sizeof(frame_str), frame_str);
  float text_width = UI_fontstyle_string_width(fstyle, frame_str);
  float box_width = MAX2(text_width + 8 * UI_DPI_FAC, 24 * UI_DPI_FAC);
  float box_padding = 3 * UI_DPI_FAC;
  const int line_outline = max_ii(1, round_fl_to_int(1 * UI_DPI_FAC));

  float bg_color[4];
  UI_GetThemeColorShade4fv(TH_CFRAME, -5, bg_color);

  /* Draw vertical line from the bottom of the current frame box to the bottom of the screen. */
  const float subframe_x = UI_view2d_view_to_region_x(v2d, BKE_scene_ctime_get(scene));
  GPUVertFormat *format = immVertexFormat();
  uint pos = GPU_vertformat_attr_add(format, "pos", GPU_COMP_F32, 2, GPU_FETCH_FLOAT);

  GPU_blend(GPU_BLEND_ALPHA);
  immBindBuiltinProgram(GPU_SHADER_3D_UNIFORM_COLOR);

  /* Outline. */
  immUniformThemeColorShadeAlpha(TH_BACK, -25, -100);
  immRectf(pos,
           subframe_x - (line_outline + U.pixelsize),
           scrub_region_rect->ymax - box_padding,
           subframe_x + (line_outline + U.pixelsize),
           0.0f);

  /* Line. */
  immUniformThemeColor(TH_CFRAME);
  immRectf(pos,
           subframe_x - U.pixelsize,
           scrub_region_rect->ymax - box_padding,
           subframe_x + U.pixelsize,
           0.0f);
  immUnbindProgram();
  GPU_blend(GPU_BLEND_NONE);

  UI_draw_roundbox_corner_set(UI_CNR_ALL);

  float outline_color[4];
  UI_GetThemeColorShade4fv(TH_CFRAME, 5, outline_color);

  UI_draw_roundbox_4fv_ex(
      &(const rctf){
          .xmin = frame_x - box_width / 2 + U.pixelsize / 2,
          .xmax = frame_x + box_width / 2 + U.pixelsize / 2,
          .ymin = scrub_region_rect->ymin + box_padding,
          .ymax = scrub_region_rect->ymax - box_padding,
      },
      bg_color,
      NULL,
      1.0f,
      outline_color,
      U.pixelsize,
      4 * UI_DPI_FAC);

  uchar text_color[4];
  UI_GetThemeColor4ubv(TH_HEADER_TEXT_HI, text_color);
  UI_fontstyle_draw_simple(fstyle,
                           frame_x - text_width / 2 + U.pixelsize / 2,
                           get_centered_text_y(scrub_region_rect),
                           frame_str,
                           text_color);
}

void ED_time_scrub_draw_current_frame(const ARegion *region,
                                      const Scene *scene,
                                      bool display_seconds)
{
  const View2D *v2d = &region->v2d;
  GPU_matrix_push_projection();
  wmOrtho2_region_pixelspace(region);

  rcti scrub_region_rect;
  ED_time_scrub_region_rect_get(region, &scrub_region_rect);

  draw_current_frame(scene, display_seconds, v2d, &scrub_region_rect, scene->r.cfra);
  GPU_matrix_pop_projection();
}

void ED_time_scrub_draw(const ARegion *region,
                        const Scene *scene,
                        bool display_seconds,
                        bool discrete_frames)
{
  const View2D *v2d = &region->v2d;

  GPU_matrix_push_projection();
  wmOrtho2_region_pixelspace(region);

  rcti scrub_region_rect;
  ED_time_scrub_region_rect_get(region, &scrub_region_rect);

  draw_background(&scrub_region_rect);

  rcti numbers_rect = scrub_region_rect;
  numbers_rect.ymin = get_centered_text_y(&scrub_region_rect) - 4 * UI_DPI_FAC;
  if (discrete_frames) {
    UI_view2d_draw_scale_x__discrete_frames_or_seconds(
        region, v2d, &numbers_rect, scene, display_seconds, TH_TEXT);
  }
  else {
    UI_view2d_draw_scale_x__frames_or_seconds(
        region, v2d, &numbers_rect, scene, display_seconds, TH_TEXT);
  }

  GPU_matrix_pop_projection();
}

bool ED_time_scrub_event_in_region(const ARegion *region, const wmEvent *event)
{
  rcti rect = region->winrct;
  rect.ymin = rect.ymax - UI_TIME_SCRUB_MARGIN_Y;
  return BLI_rcti_isect_pt_v(&rect, event->xy);
}

void ED_time_scrub_channel_search_draw(const bContext *C, ARegion *region, bDopeSheet *dopesheet)
{
  GPU_matrix_push_projection();
  wmOrtho2_region_pixelspace(region);

  rcti rect;
  rect.xmin = 0;
  rect.xmax = region->winx;
  rect.ymin = region->winy - UI_TIME_SCRUB_MARGIN_Y;
  rect.ymax = region->winy;

  uint pos = GPU_vertformat_attr_add(immVertexFormat(), "pos", GPU_COMP_F32, 2, GPU_FETCH_FLOAT);
  immBindBuiltinProgram(GPU_SHADER_3D_UNIFORM_COLOR);
  immUniformThemeColor(TH_BACK);
  immRectf(pos, rect.xmin, rect.ymin, rect.xmax, rect.ymax);
  immUnbindProgram();

  PointerRNA ptr;
  RNA_pointer_create(&CTX_wm_screen(C)->id, &RNA_DopeSheet, dopesheet, &ptr);

  const uiStyle *style = UI_style_get_dpi();
  const float padding_x = 2 * UI_DPI_FAC;
  const float padding_y = UI_DPI_FAC;

  uiBlock *block = UI_block_begin(C, region, __func__, UI_EMBOSS);
  uiLayout *layout = UI_block_layout(block,
                                     UI_LAYOUT_VERTICAL,
                                     UI_LAYOUT_HEADER,
                                     rect.xmin + padding_x,
                                     rect.ymin + UI_UNIT_Y + padding_y,
                                     BLI_rcti_size_x(&rect) - 2 * padding_x,
                                     1,
                                     0,
                                     style);
  uiLayoutSetScaleY(layout, (UI_UNIT_Y - padding_y) / UI_UNIT_Y);
  UI_block_layout_set_current(block, layout);
  UI_block_align_begin(block);
  uiItemR(layout, &ptr, "filter_text", 0, "", ICON_NONE);
  uiItemR(layout, &ptr, "use_filter_invert", 0, "", ICON_ARROW_LEFTRIGHT);
  UI_block_align_end(block);
  UI_block_layout_resolve(block, NULL, NULL);

  /* Make sure the events are consumed from the search and don't reach other UI blocks since this
   * is drawn on top of animation-channels. */
  UI_block_flag_enable(block, UI_BLOCK_CLIP_EVENTS);
  UI_block_bounds_set_normal(block, 0);
  UI_block_end(C, block);
  UI_block_draw(C, block);

  GPU_matrix_pop_projection();
}