/*
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * The Original Code is Copyright (C) 2008 Blender Foundation.
 * All rights reserved.
 */

/** \file
 * \ingroup spfile
 */

#include <math.h>
#include <string.h>
#include <errno.h>

#include "BLI_blenlib.h"
#include "BLI_utildefines.h"
#include "BLI_math.h"

#ifdef WIN32
#  include "BLI_winstuff.h"
#endif

#include "BIF_glutil.h"

#include "BKE_context.h"
#include "BKE_main.h"

#include "BLO_readfile.h"

#include "BLT_translation.h"

#include "BLF_api.h"

#include "IMB_imbuf_types.h"

#include "DNA_userdef_types.h"
#include "DNA_windowmanager_types.h"

#include "RNA_access.h"

#include "ED_fileselect.h"
#include "ED_screen.h"

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

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

#include "GPU_immediate.h"
#include "GPU_immediate_util.h"
#include "GPU_state.h"

#include "filelist.h"

#include "file_intern.h"  // own include

/* Dummy helper - we need dynamic tooltips here. */
static char *file_draw_tooltip_func(bContext *UNUSED(C), void *argN, const char *UNUSED(tip))
{
  char *dyn_tooltip = argN;
  return BLI_strdup(dyn_tooltip);
}

/* Note: This function uses pixelspace (0, 0, winx, winy), not view2d.
 * The controls are laid out as follows:
 *
 * -------------------------------------------
 * | Directory input               | execute |
 * -------------------------------------------
 * | Filename input        | + | - | cancel  |
 * -------------------------------------------
 *
 * The input widgets will stretch to fill any excess space.
 * When there isn't enough space for all controls to be shown, they are
 * hidden in this order: x/-, execute/cancel, input widgets.
 */
void file_draw_buttons(const bContext *C, ARegion *ar)
{
  /* Button layout. */
  const int max_x = ar->winx - 10;
  const int line1_y = ar->winy - (IMASEL_BUTTONS_HEIGHT / 2 + IMASEL_BUTTONS_MARGIN);
  const int line2_y = line1_y - (IMASEL_BUTTONS_HEIGHT / 2 + IMASEL_BUTTONS_MARGIN);
  const int input_minw = 20;
  const int btn_h = UI_UNIT_Y;
  const int btn_fn_w = UI_UNIT_X;
  const int btn_minw = 80;
  const int btn_margin = 20;
  const int separator = 4;

  /* Additional locals. */
  char uiblockstr[32];
  int loadbutton;
  int fnumbuttons;
  int min_x = 10;
  int chan_offs = 0;
  int available_w = max_x - min_x;
  int line1_w = available_w;
  int line2_w = available_w;

  uiBut *but;
  uiBlock *block;
  SpaceFile *sfile = CTX_wm_space_file(C);
  FileSelectParams *params = ED_fileselect_get_params(sfile);
  ARegion *artmp;
  const bool is_browse_only = (sfile->op == NULL);

  /* Initialize UI block. */
  BLI_snprintf(uiblockstr, sizeof(uiblockstr), "win %p", (void *)ar);
  block = UI_block_begin(C, ar, uiblockstr, UI_EMBOSS);

  /* exception to make space for collapsed region icon */
  for (artmp = CTX_wm_area(C)->regionbase.first; artmp; artmp = artmp->next) {
    if (artmp->regiontype == RGN_TYPE_TOOLS && artmp->flag & RGN_FLAG_HIDDEN) {
      chan_offs = 16;
      min_x += chan_offs;
      available_w -= chan_offs;
    }
  }

  /* Is there enough space for the execute / cancel buttons? */

  if (is_browse_only) {
    loadbutton = 0;
  }
  else {
    const uiFontStyle *fstyle = UI_FSTYLE_WIDGET;
    loadbutton = UI_fontstyle_string_width(fstyle, params->title) + btn_margin;
    CLAMP_MIN(loadbutton, btn_minw);
    if (available_w <= loadbutton + separator + input_minw) {
      loadbutton = 0;
    }
  }

  if (loadbutton) {
    line1_w -= (loadbutton + separator);
    line2_w = line1_w;
  }

  /* Is there enough space for file number increment/decrement buttons? */
  fnumbuttons = 2 * btn_fn_w;
  if (!loadbutton || line2_w <= fnumbuttons + separator + input_minw) {
    fnumbuttons = 0;
  }
  else {
    line2_w -= (fnumbuttons + separator);
  }

  /* Text input fields for directory and file. */
  if (available_w > 0) {
    const struct FileDirEntry *file = sfile->files ?
                                          filelist_file(sfile->files, params->active_file) :
                                          NULL;
    int overwrite_alert = file_draw_check_exists(sfile);
    const bool is_active_dir = file && (file->typeflag & FILE_TYPE_FOLDER);

    /* callbacks for operator check functions */
    UI_block_func_set(block, file_draw_check_cb, NULL, NULL);

    but = uiDefBut(block,
                   UI_BTYPE_TEXT,
                   -1,
                   "",
                   min_x,
                   line1_y,
                   line1_w - chan_offs,
                   btn_h,
                   params->dir,
                   0.0,
                   (float)FILE_MAX,
                   0,
                   0,
                   TIP_("File path"));
    UI_but_func_complete_set(but, autocomplete_directory, NULL);
    UI_but_flag_enable(but, UI_BUT_NO_UTF8);
    UI_but_flag_disable(but, UI_BUT_UNDO);
    UI_but_funcN_set(but, file_directory_enter_handle, NULL, but);

    /* TODO, directory editing is non-functional while a library is loaded
     * until this is properly supported just disable it. */
    if (sfile->files && filelist_lib(sfile->files)) {
      UI_but_flag_enable(but, UI_BUT_DISABLED);
    }

    if ((params->flag & FILE_DIRSEL_ONLY) == 0) {
      but = uiDefBut(
          block,
          UI_BTYPE_TEXT,
          -1,
          "",
          min_x,
          line2_y,
          line2_w - chan_offs,
          btn_h,
          is_active_dir ? (char *)"" : params->file,
          0.0,
          (float)FILE_MAXFILE,
          0,
          0,
          TIP_(overwrite_alert ? N_("File name, overwrite existing") : N_("File name")));
      UI_but_func_complete_set(but, autocomplete_file, NULL);
      UI_but_flag_enable(but, UI_BUT_NO_UTF8);
      UI_but_flag_disable(but, UI_BUT_UNDO);
      /* silly workaround calling NFunc to ensure this does not get called
       * immediate ui_apply_but_func but only after button deactivates */
      UI_but_funcN_set(but, file_filename_enter_handle, NULL, but);

      /* check if this overrides a file and if the operator option is used */
      if (overwrite_alert) {
        UI_but_flag_enable(but, UI_BUT_REDALERT);
      }
    }

    /* clear func */
    UI_block_func_set(block, NULL, NULL, NULL);
  }

  /* Filename number increment / decrement buttons. */
  if (fnumbuttons && (params->flag & FILE_DIRSEL_ONLY) == 0) {
    UI_block_align_begin(block);
    but = uiDefIconButO(block,
                        UI_BTYPE_BUT,
                        "FILE_OT_filenum",
                        0,
                        ICON_REMOVE,
                        min_x + line2_w + separator - chan_offs,
                        line2_y,
                        btn_fn_w,
                        btn_h,
                        TIP_("Decrement the filename number"));
    RNA_int_set(UI_but_operator_ptr_get(but), "increment", -1);

    but = uiDefIconButO(block,
                        UI_BTYPE_BUT,
                        "FILE_OT_filenum",
                        0,
                        ICON_ADD,
                        min_x + line2_w + separator + btn_fn_w - chan_offs,
                        line2_y,
                        btn_fn_w,
                        btn_h,
                        TIP_("Increment the filename number"));
    RNA_int_set(UI_but_operator_ptr_get(but), "increment", 1);
    UI_block_align_end(block);
  }

  /* Execute / cancel buttons. */
  if (loadbutton) {
    const struct FileDirEntry *file = sfile->files ?
                                          filelist_file(sfile->files, params->active_file) :
                                          NULL;
    char const *str_exec;

    if (file && FILENAME_IS_PARENT(file->relpath)) {
      str_exec = IFACE_("Parent Directory");
    }
    else if (file && file->typeflag & FILE_TYPE_DIR) {
      str_exec = IFACE_("Open Directory");
    }
    else {
      str_exec = params->title; /* params->title is already translated! */
    }

    but = uiDefButO(block,
                    UI_BTYPE_BUT,
                    "FILE_OT_execute",
                    WM_OP_EXEC_REGION_WIN,
                    str_exec,
                    max_x - loadbutton,
                    line1_y,
                    loadbutton,
                    btn_h,
                    "");
    /* Just a display hint. */
    UI_but_flag_enable(but, UI_BUT_ACTIVE_DEFAULT);

    uiDefButO(block,
              UI_BTYPE_BUT,
              "FILE_OT_cancel",
              WM_OP_EXEC_REGION_WIN,
              IFACE_("Cancel"),
              max_x - loadbutton,
              line2_y,
              loadbutton,
              btn_h,
              "");
  }

  UI_block_end(C, block);
  UI_block_draw(C, block);
}

static void draw_tile(int sx, int sy, int width, int height, int colorid, int shade)
{
  float color[4];
  UI_GetThemeColorShade4fv(colorid, shade, color);
  UI_draw_roundbox_corner_set(UI_CNR_ALL);
  UI_draw_roundbox_aa(
      true, (float)sx, (float)(sy - height), (float)(sx + width), (float)sy, 5.0f, color);
}

static void file_draw_icon(
    uiBlock *block, const char *path, int sx, int sy, int icon, int width, int height, bool drag)
{
  uiBut *but;
  int x, y;
  // float alpha = 1.0f;

  x = sx;
  y = sy - height;

  /*if (icon == ICON_FILE_BLANK) alpha = 0.375f;*/

  but = uiDefIconBut(
      block, UI_BTYPE_LABEL, 0, icon, x, y, width, height, NULL, 0.0f, 0.0f, 0.0f, 0.0f, NULL);
  UI_but_func_tooltip_set(but, file_draw_tooltip_func, BLI_strdup(path));

  if (drag) {
    /* path is no more static, cannot give it directly to but... */
    UI_but_drag_set_path(but, BLI_strdup(path), true);
  }
}

static void file_draw_string(int sx,
                             int sy,
                             const char *string,
                             float width,
                             int height,
                             eFontStyle_Align align,
                             const uchar col[4])
{
  uiStyle *style;
  uiFontStyle fs;
  rcti rect;
  char fname[FILE_MAXFILE];

  if (string[0] == '\0') {
    return;
  }

  style = UI_style_get();
  fs = style->widgetlabel;

  BLI_strncpy(fname, string, FILE_MAXFILE);
  UI_text_clip_middle_ex(&fs, fname, width, UI_DPI_ICON_SIZE, sizeof(fname), '\0');

  /* no text clipping needed, UI_fontstyle_draw does it but is a bit too strict
   * (for buttons it works) */
  rect.xmin = sx;
  rect.xmax = (int)(sx + ceil(width + 5.0f / UI_DPI_FAC));
  rect.ymin = sy - height;
  rect.ymax = sy;

  UI_fontstyle_draw(&fs,
                    &rect,
                    fname,
                    col,
                    &(struct uiFontStyleDraw_Params){
                        .align = align,
                    });
}

void file_calc_previews(const bContext *C, ARegion *ar)
{
  SpaceFile *sfile = CTX_wm_space_file(C);
  View2D *v2d = &ar->v2d;

  ED_fileselect_init_layout(sfile, ar);
  UI_view2d_totRect_set(v2d, sfile->layout->width, sfile->layout->height);
}

static void file_draw_preview(uiBlock *block,
                              const char *path,
                              int sx,
                              int sy,
                              const float icon_aspect,
                              ImBuf *imb,
                              const int icon,
                              FileLayout *layout,
                              const bool is_icon,
                              const int typeflags,
                              const bool drag)
{
  uiBut *but;
  float fx, fy;
  float dx, dy;
  int xco, yco;
  float ui_imbx, ui_imby;
  float scaledx, scaledy;
  float scale;
  int ex, ey;
  bool use_dropshadow = !is_icon && (typeflags & FILE_TYPE_IMAGE);
  float col[4] = {1.0f, 1.0f, 1.0f, 1.0f};

  BLI_assert(imb != NULL);

  ui_imbx = imb->x * UI_DPI_FAC;
  ui_imby = imb->y * UI_DPI_FAC;
  /* Unlike thumbnails, icons are not scaled up. */
  if (((ui_imbx > layout->prv_w) || (ui_imby > layout->prv_h)) ||
      (!is_icon && ((ui_imbx < layout->prv_w) || (ui_imby < layout->prv_h)))) {
    if (imb->x > imb->y) {
      scaledx = (float)layout->prv_w;
      scaledy = ((float)imb->y / (float)imb->x) * layout->prv_w;
      scale = scaledx / imb->x;
    }
    else {
      scaledy = (float)layout->prv_h;
      scaledx = ((float)imb->x / (float)imb->y) * layout->prv_h;
      scale = scaledy / imb->y;
    }
  }
  else {
    scaledx = ui_imbx;
    scaledy = ui_imby;
    scale = UI_DPI_FAC;
  }

  ex = (int)scaledx;
  ey = (int)scaledy;
  fx = ((float)layout->prv_w - (float)ex) / 2.0f;
  fy = ((float)layout->prv_h - (float)ey) / 2.0f;
  dx = (fx + 0.5f + layout->prv_border_x);
  dy = (fy + 0.5f - layout->prv_border_y);
  xco = sx + (int)dx;
  yco = sy - layout->prv_h + (int)dy;

  /* shadow */
  if (use_dropshadow) {
    UI_draw_box_shadow(220, (float)xco, (float)yco, (float)(xco + ex), (float)(yco + ey));
  }

  GPU_blend(true);

  /* the image */
  if (!is_icon && typeflags & FILE_TYPE_FTFONT) {
    UI_GetThemeColor4fv(TH_TEXT, col);
  }

  if (!is_icon && typeflags & FILE_TYPE_BLENDERLIB) {
    /* Datablock preview images use premultiplied alpha. */
    GPU_blend_set_func_separate(
        GPU_ONE, GPU_ONE_MINUS_SRC_ALPHA, GPU_ONE, GPU_ONE_MINUS_SRC_ALPHA);
  }

  IMMDrawPixelsTexState state = immDrawPixelsTexSetup(GPU_SHADER_2D_IMAGE_COLOR);
  immDrawPixelsTexScaled(&state,
                         (float)xco,
                         (float)yco,
                         imb->x,
                         imb->y,
                         GL_RGBA,
                         GL_UNSIGNED_BYTE,
                         GL_NEAREST,
                         imb->rect,
                         scale,
                         scale,
                         1.0f,
                         1.0f,
                         col);

  GPU_blend_set_func_separate(
      GPU_SRC_ALPHA, GPU_ONE_MINUS_SRC_ALPHA, GPU_ONE, GPU_ONE_MINUS_SRC_ALPHA);

  if (icon) {
    UI_icon_draw_ex((float)xco + (7 * UI_DPI_FAC),
                    (float)yco + (7 * UI_DPI_FAC),
                    icon,
                    icon_aspect,
                    1.0f,
                    0.0f,
                    NULL,
                    false);
  }

  /* border */
  if (use_dropshadow) {
    GPUVertFormat *format = immVertexFormat();
    uint pos = GPU_vertformat_attr_add(format, "pos", GPU_COMP_F32, 2, GPU_FETCH_FLOAT);

    immBindBuiltinProgram(GPU_SHADER_2D_UNIFORM_COLOR);
    immUniformColor4f(0.0f, 0.0f, 0.0f, 0.4f);
    imm_draw_box_wire_2d(pos, (float)xco, (float)yco, (float)(xco + ex), (float)(yco + ey));
    immUnbindProgram();
  }

  but = uiDefBut(block, UI_BTYPE_LABEL, 0, "", xco, yco, ex, ey, NULL, 0.0, 0.0, 0, 0, NULL);
  UI_but_func_tooltip_set(but, file_draw_tooltip_func, BLI_strdup(path));

  /* dragregion */
  if (drag) {
    /* path is no more static, cannot give it directly to but... */
    UI_but_drag_set_image(but, BLI_strdup(path), icon, imb, scale, true);
  }

  GPU_blend(false);
}

static void renamebutton_cb(bContext *C, void *UNUSED(arg1), char *oldname)
{
  Main *bmain = CTX_data_main(C);
  char newname[FILE_MAX + 12];
  char orgname[FILE_MAX + 12];
  char filename[FILE_MAX + 12];
  wmWindowManager *wm = CTX_wm_manager(C);
  SpaceFile *sfile = (SpaceFile *)CTX_wm_space_data(C);
  ScrArea *sa = CTX_wm_area(C);
  ARegion *ar = CTX_wm_region(C);

  const char *blendfile_path = BKE_main_blendfile_path(bmain);
  BLI_make_file_string(blendfile_path, orgname, sfile->params->dir, oldname);
  BLI_strncpy(filename, sfile->params->renamefile, sizeof(filename));
  BLI_filename_make_safe(filename);
  BLI_make_file_string(blendfile_path, newname, sfile->params->dir, filename);

  if (!STREQ(orgname, newname)) {
    if (!BLI_exists(newname)) {
      errno = 0;
      if ((BLI_rename(orgname, newname) != 0) || !BLI_exists(newname)) {
        WM_reportf(RPT_ERROR, "Could not rename: %s", errno ? strerror(errno) : "unknown error");
        WM_report_banner_show();
      }
      else {
        /* If rename is sucessfull, scroll to newly renamed entry. */
        BLI_strncpy(sfile->params->renamefile, filename, sizeof(sfile->params->renamefile));
        sfile->params->rename_flag = FILE_PARAMS_RENAME_POSTSCROLL_PENDING;

        if (sfile->smoothscroll_timer != NULL) {
          WM_event_remove_timer(CTX_wm_manager(C), CTX_wm_window(C), sfile->smoothscroll_timer);
        }
        sfile->smoothscroll_timer = WM_event_add_timer(wm, CTX_wm_window(C), TIMER1, 1.0 / 1000.0);
        sfile->scroll_offset = 0;
      }

      /* to make sure we show what is on disk */
      ED_fileselect_clear(wm, sa, sfile);
    }

    ED_region_tag_redraw(ar);
  }
}

static void draw_background(FileLayout *layout, View2D *v2d)
{
  int i;
  int sy;

  uint pos = GPU_vertformat_attr_add(immVertexFormat(), "pos", GPU_COMP_F32, 2, GPU_FETCH_FLOAT);
  immBindBuiltinProgram(GPU_SHADER_2D_UNIFORM_COLOR);
  immUniformThemeColorShade(TH_BACK, -7);

  /* alternating flat shade background */
  for (i = 0; (i <= layout->rows); i += 2) {
    sy = (int)v2d->cur.ymax - i * (layout->tile_h + 2 * layout->tile_border_y) -
         layout->tile_border_y;

    immRectf(pos,
             v2d->cur.xmin,
             (float)sy,
             v2d->cur.xmax,
             (float)(sy + layout->tile_h + 2 * layout->tile_border_y));
  }

  immUnbindProgram();
}

static void draw_dividers(FileLayout *layout, View2D *v2d)
{
  /* vertical column dividers */

  const int step = (layout->tile_w + 2 * layout->tile_border_x);

  unsigned int vertex_len = 0;
  int sx = (int)v2d->tot.xmin;
  while (sx < v2d->cur.xmax) {
    sx += step;
    vertex_len += 4; /* vertex_count = 2 points per line * 2 lines per divider */
  }

  if (vertex_len > 0) {
    int v1[2], v2[2];
    unsigned char col_hi[3], col_lo[3];

    UI_GetThemeColorShade3ubv(TH_BACK, 30, col_hi);
    UI_GetThemeColorShade3ubv(TH_BACK, -30, col_lo);

    v1[1] = v2d->cur.ymax - layout->tile_border_y;
    v2[1] = v2d->cur.ymin;

    GPUVertFormat *format = immVertexFormat();
    uint pos = GPU_vertformat_attr_add(format, "pos", GPU_COMP_I32, 2, GPU_FETCH_INT_TO_FLOAT);
    uint color = GPU_vertformat_attr_add(
        format, "color", GPU_COMP_U8, 3, GPU_FETCH_INT_TO_FLOAT_UNIT);

    immBindBuiltinProgram(GPU_SHADER_2D_FLAT_COLOR);
    immBegin(GPU_PRIM_LINES, vertex_len);

    sx = (int)v2d->tot.xmin;
    while (sx < v2d->cur.xmax) {
      sx += step;

      v1[0] = v2[0] = sx;
      immAttrSkip(color);
      immVertex2iv(pos, v1);
      immAttr3ubv(color, col_lo);
      immVertex2iv(pos, v2);

      v1[0] = v2[0] = sx + 1;
      immAttrSkip(color);
      immVertex2iv(pos, v1);
      immAttr3ubv(color, col_hi);
      immVertex2iv(pos, v2);
    }

    immEnd();
    immUnbindProgram();
  }
}

void file_draw_list(const bContext *C, ARegion *ar)
{
  SpaceFile *sfile = CTX_wm_space_file(C);
  FileSelectParams *params = ED_fileselect_get_params(sfile);
  FileLayout *layout = ED_fileselect_get_layout(sfile, ar);
  View2D *v2d = &ar->v2d;
  struct FileList *files = sfile->files;
  struct FileDirEntry *file;
  const char *root = filelist_dir(files);
  ImBuf *imb;
  uiBlock *block = UI_block_begin(C, ar, __func__, UI_EMBOSS);
  int numfiles;
  int numfiles_layout;
  int sx, sy;
  int offset;
  int textwidth, textheight;
  int i;
  bool is_icon;
  eFontStyle_Align align;
  bool do_drag;
  int column_space = 0.6f * UI_UNIT_X;
  unsigned char text_col[4];
  const bool small_size = SMALL_SIZE_CHECK(params->thumbnail_size);
  const bool update_stat_strings = small_size != SMALL_SIZE_CHECK(layout->curr_size);
  const float thumb_icon_aspect = sqrtf(64.0f / (float)(params->thumbnail_size));

  numfiles = filelist_files_ensure(files);

  if (params->display != FILE_IMGDISPLAY) {

    draw_background(layout, v2d);

    draw_dividers(layout, v2d);
  }

  offset = ED_fileselect_layout_offset(layout, (int)ar->v2d.cur.xmin, (int)-ar->v2d.cur.ymax);
  if (offset < 0) {
    offset = 0;
  }

  numfiles_layout = ED_fileselect_layout_numfiles(layout, ar);

  /* adjust, so the next row is already drawn when scrolling */
  if (layout->flag & FILE_LAYOUT_HOR) {
    numfiles_layout += layout->rows;
  }
  else {
    numfiles_layout += layout->columns;
  }

  filelist_file_cache_slidingwindow_set(files, numfiles_layout);

  textwidth = (FILE_IMGDISPLAY == params->display) ? layout->tile_w :
                                                     (int)layout->column_widths[COLUMN_NAME];
  textheight = (int)(layout->textheight * 3.0 / 2.0 + 0.5);

  align = (FILE_IMGDISPLAY == params->display) ? UI_STYLE_TEXT_CENTER : UI_STYLE_TEXT_LEFT;

  if (numfiles > 0) {
    const bool success = filelist_file_cache_block(
        files, min_ii(offset + (numfiles_layout / 2), numfiles - 1));
    BLI_assert(success);
    UNUSED_VARS_NDEBUG(success);

    filelist_cache_previews_update(files);

    /* Handle preview timer here,
     * since it's filelist_file_cache_block() and filelist_cache_previews_update()
     * which controls previews task. */
    {
      const bool previews_running = filelist_cache_previews_running(files);
      //          printf("%s: preview task: %d\n", __func__, previews_running);
      if (previews_running && !sfile->previews_timer) {
        sfile->previews_timer = WM_event_add_timer_notifier(
            CTX_wm_manager(C), CTX_wm_window(C), NC_SPACE | ND_SPACE_FILE_PREVIEW, 0.01);
      }
      if (!previews_running && sfile->previews_timer) {
        /* Preview is not running, no need to keep generating update events! */
        //              printf("%s: Inactive preview task, sleeping!\n", __func__);
        WM_event_remove_timer_notifier(CTX_wm_manager(C), CTX_wm_window(C), sfile->previews_timer);
        sfile->previews_timer = NULL;
      }
    }
  }

  BLF_batch_draw_begin();

  for (i = offset; (i < numfiles) && (i < offset + numfiles_layout); i++) {
    unsigned int file_selflag;
    char path[FILE_MAX_LIBEXTRA];
    ED_fileselect_layout_tilepos(layout, i, &sx, &sy);
    sx += (int)(v2d->tot.xmin + 0.1f * UI_UNIT_X);
    sy = (int)(v2d->tot.ymax - sy);

    file = filelist_file(files, i);
    file_selflag = filelist_entry_select_get(sfile->files, file, CHECK_ALL);

    BLI_join_dirfile(path, sizeof(path), root, file->relpath);

    if (!(file_selflag & FILE_SEL_EDITING)) {
      if ((params->highlight_file == i) || (file_selflag & FILE_SEL_HIGHLIGHTED) ||
          (file_selflag & FILE_SEL_SELECTED)) {
        int colorid = (file_selflag & FILE_SEL_SELECTED) ? TH_HILITE : TH_BACK;
        int shade = (params->highlight_file == i) || (file_selflag & FILE_SEL_HIGHLIGHTED) ? 35 :
                                                                                             0;

        BLI_assert(i == 0 || !FILENAME_IS_CURRPAR(file->relpath));

        draw_tile(sx,
                  sy - 1,
                  layout->tile_w + 4,
                  sfile->layout->tile_h + layout->tile_border_y,
                  colorid,
                  shade);
      }
    }
    UI_draw_roundbox_corner_set(UI_CNR_NONE);

    /* don't drag parent or refresh items */
    do_drag = !(FILENAME_IS_CURRPAR(file->relpath));

    if (FILE_IMGDISPLAY == params->display) {
      const int icon = filelist_geticon(files, i, false);
      is_icon = 0;
      imb = filelist_getimage(files, i);
      if (!imb) {
        imb = filelist_geticon_image(files, i);
        is_icon = 1;
      }

      file_draw_preview(block,
                        path,
                        sx,
                        sy,
                        thumb_icon_aspect,
                        imb,
                        icon,
                        layout,
                        is_icon,
                        file->typeflag,
                        do_drag);
    }
    else {
      file_draw_icon(block,
                     path,
                     sx,
                     sy - (UI_UNIT_Y / 6),
                     filelist_geticon(files, i, true),
                     ICON_DEFAULT_WIDTH_SCALE,
                     ICON_DEFAULT_HEIGHT_SCALE,
                     do_drag);
      sx += ICON_DEFAULT_WIDTH_SCALE + 0.2f * UI_UNIT_X;
    }

    UI_GetThemeColor4ubv(TH_TEXT, text_col);

    if (file_selflag & FILE_SEL_EDITING) {
      uiBut *but;
      short width;

      if (params->display == FILE_SHORTDISPLAY) {
        width = layout->tile_w - (ICON_DEFAULT_WIDTH_SCALE + 0.2f * UI_UNIT_X);
      }
      else if (params->display == FILE_LONGDISPLAY) {
        width = layout->column_widths[COLUMN_NAME] + (column_space * 3.5f);
      }
      else {
        BLI_assert(params->display == FILE_IMGDISPLAY);
        width = textwidth;
      }

      but = uiDefBut(block,
                     UI_BTYPE_TEXT,
                     1,
                     "",
                     sx,
                     sy - layout->tile_h - 0.15f * UI_UNIT_X,
                     width,
                     textheight,
                     sfile->params->renamefile,
                     1.0f,
                     (float)sizeof(sfile->params->renamefile),
                     0,
                     0,
                     "");
      UI_but_func_rename_set(but, renamebutton_cb, file);
      UI_but_flag_enable(but, UI_BUT_NO_UTF8); /* allow non utf8 names */
      UI_but_flag_disable(but, UI_BUT_UNDO);
      if (false == UI_but_active_only(C, ar, block, but)) {
        file_selflag = filelist_entry_select_set(
            sfile->files, file, FILE_SEL_REMOVE, FILE_SEL_EDITING, CHECK_ALL);
      }
    }

    if (!(file_selflag & FILE_SEL_EDITING)) {
      int tpos = (FILE_IMGDISPLAY == params->display) ? sy - layout->tile_h + layout->textheight :
                                                        sy;
      file_draw_string(sx + 1, tpos, file->name, (float)textwidth, textheight, align, text_col);
    }

    sx += (int)layout->column_widths[COLUMN_NAME] + column_space;
    if (params->display == FILE_SHORTDISPLAY) {
      if ((file->typeflag & (FILE_TYPE_BLENDER | FILE_TYPE_BLENDER_BACKUP)) ||
          !(file->typeflag & (FILE_TYPE_DIR | FILE_TYPE_BLENDERLIB))) {
        if ((file->entry->size_str[0] == '\0') || update_stat_strings) {
          BLI_filelist_entry_size_to_string(
              NULL, file->entry->size, small_size, file->entry->size_str);
        }
        file_draw_string(sx,
                         sy,
                         file->entry->size_str,
                         layout->column_widths[COLUMN_SIZE],
                         layout->tile_h,
                         align,
                         text_col);
      }
      sx += (int)layout->column_widths[COLUMN_SIZE] + column_space;
    }
    else if (params->display == FILE_LONGDISPLAY) {
      if (!(file->typeflag & FILE_TYPE_BLENDERLIB) && !FILENAME_IS_CURRPAR(file->relpath)) {
        if ((file->entry->date_str[0] == '\0') || update_stat_strings) {
          BLI_filelist_entry_datetime_to_string(
              NULL, file->entry->time, small_size, file->entry->time_str, file->entry->date_str);
        }
        file_draw_string(sx,
                         sy,
                         file->entry->date_str,
                         layout->column_widths[COLUMN_DATE],
                         layout->tile_h,
                         align,
                         text_col);
        sx += (int)layout->column_widths[COLUMN_DATE] + column_space;
        file_draw_string(sx,
                         sy,
                         file->entry->time_str,
                         layout->column_widths[COLUMN_TIME],
                         layout->tile_h,
                         align,
                         text_col);
        sx += (int)layout->column_widths[COLUMN_TIME] + column_space;
      }
      else {
        sx += (int)layout->column_widths[COLUMN_DATE] + column_space;
        sx += (int)layout->column_widths[COLUMN_TIME] + column_space;
      }

      if ((file->typeflag & (FILE_TYPE_BLENDER | FILE_TYPE_BLENDER_BACKUP)) ||
          !(file->typeflag & (FILE_TYPE_DIR | FILE_TYPE_BLENDERLIB))) {
        if ((file->entry->size_str[0] == '\0') || update_stat_strings) {
          BLI_filelist_entry_size_to_string(
              NULL, file->entry->size, small_size, file->entry->size_str);
        }
        file_draw_string(sx,
                         sy,
                         file->entry->size_str,
                         layout->column_widths[COLUMN_SIZE],
                         layout->tile_h,
                         align,
                         text_col);
      }
      sx += (int)layout->column_widths[COLUMN_SIZE] + column_space;
    }
  }

  BLF_batch_draw_end();

  UI_block_end(C, block);
  UI_block_draw(C, block);

  layout->curr_size = params->thumbnail_size;
}