#!/bin/sh
# ArtCraft Launcher AppImage entry point (packaging/linux/AppRun; installed by package.sh).
#
# On Wayland the compositor resolves a window's dock icon by taking the window's
# app_id (ai.storyteller.artcraft-launcher) and looking up an installed .desktop file.
# An AppImage installs nothing, so every AppImage run would otherwise show the
# generic "Wayland" icon. Best-effort desktop integration: on first run
# (and whenever the AppImage's path changes) install the .desktop entry and the
# hicolor icons into $XDG_DATA_HOME, then launch. Every failure here must leave
# the launch untouched. AppImage managers can opt out with DESKTOPINTEGRATION=1,
# and users with ARTCRAFT_LAUNCHER_NO_DESKTOP_INTEGRATION=1. Nothing is installed
# while another entry (appimaged, AppImageLauncher, Gear Lever) runs this AppImage.

set -u

APPDIR="$(dirname "$(readlink -f "$0")")"
DESK_ID=ai.storyteller.artcraft-launcher

integrate() {
  case "${ARTCRAFT_LAUNCHER_NO_DESKTOP_INTEGRATION:-}" in
    1 | true | yes) return 0 ;;
  esac
  case "${DESKTOPINTEGRATION:-}" in
    1 | true | yes) return 0 ;;
  esac
  # The AppImage runtime exports $APPIMAGE; without it (an extracted AppDir) there
  # is no path to register and nothing to do.
  appimage="${APPIMAGE:-}"
  [ -n "$appimage" ] && [ -f "$appimage" ] || return 0
  appimage="$(readlink -f "$appimage")" || return 0
  # Exec= is parsed by the desktop: a path holding a quote, backquote, dollar, backslash,
  # percent or a line break would need escaping (or could add lines), so skip integration.
  case "$appimage" in
    *[\"\`\$\\%]* | *'
'*) return 0 ;;
  esac
  home="${HOME:-}"
  [ -n "$home" ] || return 0
  data="${XDG_DATA_HOME:-$home/.local/share}"
  src_desktop="$APPDIR/usr/share/applications/$DESK_ID.desktop"
  [ -f "$src_desktop" ] || return 0
  apps="$data/applications"
  # A second entry would list the app twice; drop the one we wrote if it is unchanged.
  if other_entry_runs "$apps" "$appimage"; then
    if own_entry "$apps/$DESK_ID.desktop" && rm -f "$apps/$DESK_ID.desktop"; then
      command -v update-desktop-database >/dev/null 2>&1 && update-desktop-database "$apps" >/dev/null 2>&1
    fi
    return 0
  fi

  # Rewrite Exec to this AppImage (the binary is not on the host PATH) and drop
  # TryExec, which would hide the entry; everything else is shipped as packaged.
  mkdir -p "$apps" 2>/dev/null || return 0
  tmp="$apps/.$DESK_ID.tmp.$$"
  esc="$(printf '%s' "$appimage" | sed 's/[\\&|]/\\&/g')"
  if sed -e "s|^Exec=.*|Exec=\"$esc\"|" -e '/^TryExec=/d' "$src_desktop" 2>/dev/null >"$tmp" &&
    printf '%s\n' "X-ArtCraft-Launcher-Generated-Exec=\"$appimage\"" >>"$tmp"; then
    if cmp -s "$tmp" "$apps/$DESK_ID.desktop"; then
      rm -f "$tmp"
    elif [ ! -e "$apps/$DESK_ID.desktop" ] && [ ! -L "$apps/$DESK_ID.desktop" ] || own_entry "$apps/$DESK_ID.desktop"; then
      if mv -f "$tmp" "$apps/$DESK_ID.desktop" 2>/dev/null; then
        command -v update-desktop-database >/dev/null 2>&1 && update-desktop-database "$apps" >/dev/null 2>&1
      else
        rm -f "$tmp"
      fi
    else
      # Keep manager metadata and user changes, including a custom Exec environment.
      rm -f "$tmp"
    fi
  else
    rm -f "$tmp"
    return 0
  fi

  # Icons: per-file compare so an unchanged install costs a handful of cmp calls.
  src_icons="$APPDIR/usr/share/icons/hicolor"
  [ -d "$src_icons" ] || return 0
  icons="$data/icons/hicolor"
  (cd "$src_icons" && find . -type f) | {
    changed=false
    while IFS= read -r rel; do
      mkdir -p "$icons/$(dirname "$rel")" 2>/dev/null || continue
      if ! cmp -s "$src_icons/$rel" "$icons/$rel"; then
        if cp "$src_icons/$rel" "$icons/$rel" 2>/dev/null; then
          changed=true
        fi
      fi
    done
    if [ "$changed" = true ] && command -v gtk-update-icon-cache >/dev/null 2>&1; then
      # A per-user hicolor directory need not have index.theme; -t permits that.
      gtk-update-icon-cache -f -t "$icons" >/dev/null 2>&1 || true
    fi
  }
}

# Refresh only an unchanged entry whose Exec still matches the executable we wrote.
# Unmarked legacy entries and customized or ambiguous executable fields are preserved.
own_entry() {
  [ -f "$1" ] && [ ! -L "$1" ] || return 1
  [ "$(grep -c '^Exec=' "$1")" = 1 ] || return 1
  [ "$(grep -c '^X-ArtCraft-Launcher-Generated-Exec=' "$1")" = 1 ] || return 1
  grep -Eq '^Exec="/[^"`$\\%]+"$' "$1" || return 1
  existing_exec="$(sed -n 's/^Exec=//p' "$1")" || return 1
  generated_exec="$(sed -n 's/^X-ArtCraft-Launcher-Generated-Exec=//p' "$1")" || return 1
  [ "$existing_exec" = "$generated_exec" ] || return 1
  expected_body="$(sed -e '/^Exec=/d' -e '/^TryExec=/d' "$src_desktop")" || return 1
  existing_body="$(sed -e '/^Exec=/d' -e '/^X-ArtCraft-Launcher-Generated-Exec=/d' "$1")" || return 1
  # Entries written before the StartupWMClass fix differ only in that line.
  old_body="$(printf '%s\n' "$expected_body" | sed 's/^StartupWMClass=.*/StartupWMClass=artcraft-launcher/')"
  [ "$expected_body" = "$existing_body" ] || [ "$old_body" = "$existing_body" ]
}

# True when a visible entry in $1 other than ours runs the AppImage $2 and has our window class.
other_entry_runs() {
  grep -lF -e "$2" "$1"/*.desktop 2>/dev/null | (
    while IFS= read -r f; do
      [ "$f" = "$1/$DESK_ID.desktop" ] && continue
      main=false runs=false class=false
      while IFS= read -r line || [ -n "$line" ]; do
        # Only the [Desktop Entry] group; an action's Exec isn't what the entry launches.
        case "$line" in
          "[Desktop Entry]") main=true && continue ;;
          "["*) main=false ;;
        esac
        [ "$main" = true ] || continue
        case "$line" in
          # Menu editors hide an entry this way; it lists nothing.
          Hidden=true | NoDisplay=true) runs=false && break ;;
          # A class from before an in-place update can't match the window, so ours has to stay.
          "StartupWMClass=$DESK_ID") class=true ;;
          Exec=*"$2" | Exec=*"$2 "* | Exec=*"$2\""* | Exec=*"$2'"*) runs=true ;;
        esac
      done <"$f"
      [ "$runs" = true ] && [ "$class" = true ] && exit 0
    done
    exit 1
  )
}

integrate
exec "$APPDIR/usr/bin/artcraft-launcher" "$@"