#!/usr/bin/env bash
set -euo pipefail

app_dir="$(CDPATH= cd -- "$(dirname -- "$0")" && pwd)"

integrate_appimage() {
  if [[ -z "${APPIMAGE:-}" || ! -f "$APPIMAGE" ]]; then
    printf 'Desktop integration must be run from the packaged AppImage.\n' >&2
    exit 1
  fi

  local data_home="${XDG_DATA_HOME:-$HOME/.local/share}"
  if [[ -e "$data_home/appimagekit/no_desktopintegration" \
    || -e /usr/share/appimagekit/no_desktopintegration \
    || -e /etc/appimagekit/no_desktopintegration \
    || -n "${DESKTOPINTEGRATION:-}" ]]; then
    printf 'Desktop integration is disabled or already managed on this system.\n' >&2
    exit 1
  fi
  if command -v pgrep >/dev/null 2>&1 && pgrep -x appimaged >/dev/null 2>&1; then
    printf 'Desktop integration is already managed by appimaged.\n' >&2
    exit 1
  fi

  local applications_dir="$HOME/Applications"
  local installed_appimage="$applications_dir/flectar-mail.AppImage"
  local desktop_dir="$data_home/applications"
  local icon_root="$data_home/icons/hicolor"
  local desktop_file="$desktop_dir/com.flectar.mail.desktop"
  local desktop_exec

  if [[ "$(readlink -f "$APPIMAGE")" != "$(readlink -m "$installed_appimage")" ]]; then
    install -Dm755 "$APPIMAGE" "$installed_appimage.new"
    mv -f "$installed_appimage.new" "$installed_appimage"
  else
    chmod 0755 "$installed_appimage"
  fi
  install -Dm644 \
    "$app_dir/usr/share/icons/hicolor/512x512/apps/com.flectar.mail.png" \
    "$icon_root/512x512/apps/com.flectar.mail.png"
  install -Dm644 \
    "$app_dir/usr/share/icons/hicolor/scalable/apps/com.flectar.mail.svg" \
    "$icon_root/scalable/apps/com.flectar.mail.svg"
  install -d "$desktop_dir"

  # A Wayland compositor resolves the xdg app-id from this exact desktop-file
  # basename. Point Exec at the installed AppImage without changing that ID.
  desktop_exec=${installed_appimage//\\/\\\\}
  desktop_exec=${desktop_exec//\"/\\\"}
  desktop_exec=${desktop_exec//\`/\\\`}
  desktop_exec=${desktop_exec//\$/\\\$}
  while IFS= read -r line || [[ -n "$line" ]]; do
    if [[ "$line" == Exec=* ]]; then
      printf 'Exec="%s"\n' "$desktop_exec"
    else
      printf '%s\n' "$line"
    fi
  done < "$app_dir/usr/share/applications/com.flectar.mail.desktop" \
    > "$desktop_file.new"
  chmod 0644 "$desktop_file.new"
  mv -f "$desktop_file.new" "$desktop_file"

  if command -v desktop-file-validate >/dev/null 2>&1; then
    desktop-file-validate "$desktop_file"
  fi
  if command -v update-desktop-database >/dev/null 2>&1; then
    update-desktop-database "$desktop_dir"
  fi
  if command -v gtk-update-icon-cache >/dev/null 2>&1; then
    gtk-update-icon-cache -f -t "$icon_root" >/dev/null 2>&1 || true
  fi

  printf 'Integrated Flectar Mail at %s\n' "$installed_appimage"
  printf 'Launch it from the desktop application menu.\n'
}

if [[ "${1:-}" == "--integrate" ]]; then
  integrate_appimage
  exit 0
fi

# The mail shell has a small number of worker threads. One glibc allocation
# arena is enough and prevents per-thread arenas from retaining render/sync
# scratch memory after a burst of work. Respect an explicit user override.
export MALLOC_ARENA_MAX="${MALLOC_ARENA_MAX:-1}"
export MALLOC_TRIM_THRESHOLD_="${MALLOC_TRIM_THRESHOLD_:-65536}"

# Preserve the host search path for external programs such as the browser.
export FLECTAR_MAIL_HOST_LD_LIBRARY_PATH="${LD_LIBRARY_PATH-}"
export FLECTAR_MAIL_BUNDLED=1

# linuxdeploy places any non-system ELF dependencies here.
export LD_LIBRARY_PATH="$app_dir/usr/lib${LD_LIBRARY_PATH:+:$LD_LIBRARY_PATH}"
# The Linux binary supports Slint's Wayland and X11 winit integrations. Slint
# paints every application control while the window system owns window chrome.
export SLINT_BACKEND="${SLINT_BACKEND:-winit-software}"

# Keep the process name stable. Some native UI/runtime discovery code uses
# argv[0], while the generic cargo-appimage runner passes "AppRun" here.
exec -a flectar-mail "$app_dir/usr/bin/flectar-mail" "$@"