#!/bin/bash

# omarchy:summary=Give terminals, btop, and GTK apps a see-through background while windows are glassy
# omarchy:args=[theme-dir]
# omarchy:hidden=true

# A Hyprland opacity rule fades a terminal's text along with its background,
# and foot turns compositor blur down unless its own config asks for it, so the
# glass belongs in each terminal's theme file, as in the glassy Starship
# (#14726). The lines sit between markers so leaving glassy takes them out
# again, and a theme that sets its own opacity keeps it.

THEME_DIR="${1:-$HOME/.local/state/omarchy/current/theme}"
TOGGLES_DIR="${XDG_STATE_HOME:-$HOME/.local/state}/omarchy/toggles/hypr"
GLASSY=false
[[ -f $TOGGLES_DIR/window-glassy.lua ]] && GLASSY=true
status=0

# A literal for a sed address, whose delimiter is /.
regex() {
  sed 's/[][\\.*^$/]/\\&/g' <<<"$1"
}

# A block added to a file that did not end in a newline has to supply one, so
# its begin marker says so, and taking the block out takes that newline back.
# Leaving glassy then gives the file back exactly as it was. Markers come as
# an opening and a closing part, so CSS can wrap them in a comment.
remove_block() {
  local file="$1" open="$2" close="$3"
  local begin end
  begin=$(regex "$open omarchy-glass begin")
  end=$(regex "$open omarchy-glass end$close")
  [[ -f $file ]] && grep -qF "$open omarchy-glass begin" "$file" || return 0

  local added_newline=false
  grep -qxF "$open omarchy-glass begin after a line without a newline$close" "$file" && added_newline=true
  sed -i "/^$begin/,/^$end\$/d" "$file" || return 1
  if [[ $added_newline == "true" && -s $file && -z $(tail -c 1 "$file") ]]; then
    truncate -s -1 "$file" || return 1
  fi
}

append_block() {
  local file="$1" open="$2" close="$3" lines="$4"
  if [[ -s $file && -n $(tail -c 1 "$file") ]]; then
    printf '\n%s\n%s\n%s\n' "$open omarchy-glass begin after a line without a newline$close" "$lines" "$open omarchy-glass end$close" >>"$file"
  else
    printf '%s\n%s\n%s\n' "$open omarchy-glass begin$close" "$lines" "$open omarchy-glass end$close" >>"$file"
  fi
}

# Each setting comes with a pattern for the theme setting it already, which
# keeps the theme's own; an empty pattern always adds it. Lines that belong in
# a section go in under its header. A file that already has the section gets
# them inside it, since TOML refuses a table declared twice; otherwise the
# header comes along with them.
glass() {
  local file="$THEME_DIR/$1" section="$2"
  shift 2
  [[ -f $file ]] || return 0

  remove_block "$file" "#" "" || return 1
  [[ $GLASSY == "true" ]] || return 0

  local lines=""
  while (( $# >= 2 )); do
    if [[ -z $1 ]] || ! grep -qE "$1" "$file"; then
      lines+="${lines:+$'\n'}$2"
    fi
    shift 2
  done
  [[ -n $lines ]] || return 0

  # A header may carry trailing space or a comment.
  local header="^$(regex "$section")[[:space:]]*(#.*)?\$"
  if [[ -n $section ]] && grep -qE "$header" "$file"; then
    local block
    block=$(mktemp) || return 1
    printf '# omarchy-glass begin\n%s\n# omarchy-glass end\n' "$lines" >"$block"
    sed -i -E "0,/$header/{/$header/r $block
}" "$file"
    local result=$?
    rm -f "$block"
    return $result
  fi

  append_block "$file" "#" "" "${section:+$section$'\n'}$lines"
}

# Alacritty's own blur works only on macOS and KDE; Hyprland blurs it anyway.
glass alacritty.toml '[window]' \
  '^[[:space:]]*opacity[[:space:]]*=' 'opacity = 0.65' || status=1
glass foot.ini '[colors-dark]' \
  '^[[:space:]]*alpha[[:space:]]*=' 'alpha=0.65' \
  '^[[:space:]]*blur[[:space:]]*=' 'blur=yes' || status=1
glass kitty.conf '' \
  '^[[:space:]]*background_opacity[[:space:]]' 'background_opacity 0.65' || status=1
# btop paints its own background over the terminal's glass. An empty main_bg
# uses the terminal background; the last theme value wins, so removing the
# block restores the theme's colour without changing btop's user config.
glass btop.theme '' \
  '^[[:space:]]*theme\[main_bg\][[:space:]]*=[[:space:]]*""' 'theme[main_bg]=""' || status=1
# GTK only asks Hyprland for blur under a CSS backdrop-filter, which Ghostty
# takes as custom CSS and reloads live; its background-blur speaks only KDE's
# blur protocol.
glass ghostty.conf '' \
  '^[[:space:]]*background-opacity[[:space:]]*=' 'background-opacity = 0.65' \
  '' "gtk-custom-css = $OMARCHY_PATH/default/gtk/glass.css" || status=1

# Other GTK apps, such as Nautilus, read the user's gtk.css at launch, so the
# same backdrop blur is imported there. It follows the mode alone, so a theme
# switch, which names the theme it is rendering, leaves it be.
if (( $# == 0 )); then
  gtk_css="${XDG_CONFIG_HOME:-$HOME/.config}/gtk-4.0/gtk.css"
  remove_block "$gtk_css" "/*" " */" || status=1
  if [[ $GLASSY == "true" ]]; then
    { mkdir -p "${gtk_css%/*}" &&
      append_block "$gtk_css" "/*" " */" "@import url(\"file://$OMARCHY_PATH/default/gtk/glass.css\");"; } || status=1
  fi
fi

exit $status