#!/bin/sh

set -eu

APP_NAME="Lumide"
APP_ID="io.sofluffy.lumide"
REPO="SoFluffyOS/lumide"
API_ROOT="https://api.github.com/repos/$REPO/releases"
INSTALL_ROOT="${LUMIDE_INSTALL_DIR:-$HOME/.local/opt/lumide}"
BIN_DIR="${LUMIDE_BIN_DIR:-$HOME/.local/bin}"
XDG_DATA_HOME_DIR="${XDG_DATA_HOME:-$HOME/.local/share}"
DESKTOP_DIR="$XDG_DATA_HOME_DIR/applications"
ICON_DIR="$XDG_DATA_HOME_DIR/icons/hicolor/512x512/apps"
VERSION="${LUMIDE_VERSION:-latest}"

say() {
  printf '%s\n' "$1"
}

fail() {
  printf 'Error: %s\n' "$1" >&2
  exit 1
}

need_cmd() {
  command -v "$1" >/dev/null 2>&1 || fail "missing required command '$1'"
}

detect_arch() {
  case "$(uname -m)" in
    x86_64|amd64) printf 'x86_64' ;;
    aarch64|arm64) printf 'arm64' ;;
    *) fail "unsupported architecture '$(uname -m)'" ;;
  esac
}

need_cmd curl
need_cmd mktemp
need_cmd install
need_cmd sed

extract_asset_url() {
  sed -n 's/.*"browser_download_url":[[:space:]]*"\([^"]*\)".*/\1/p' | sed 's#\\/#/#g'
}

github_curl() {
  TOKEN="${GITHUB_TOKEN:-${LUMIDE_GITHUB_TOKEN:-}}"
  if [ -n "$TOKEN" ]; then
    curl -fsSL -H "User-Agent: Lumide-Installer" -H "Accept: application/vnd.github+json" -H "Authorization: Bearer $TOKEN" "$@"
  else
    curl -fsSL -H "User-Agent: Lumide-Installer" -H "Accept: application/vnd.github+json" "$@"
  fi
}

ARCH=$(detect_arch)
if [ "$VERSION" = "latest" ]; then
  RELEASE_API_URL="$API_ROOT/latest"
else
  RELEASE_API_URL="$API_ROOT/tags/$VERSION"
fi

TMP_DIR=$(mktemp -d)
cleanup() {
  rm -rf "$TMP_DIR"
}
trap cleanup EXIT INT TERM

say "Resolving Linux release asset for $ARCH"
CURL_ERR_FILE="$TMP_DIR/curl_err.log"
if ! RELEASE_JSON=$(github_curl "$RELEASE_API_URL" 2>"$CURL_ERR_FILE"); then
  if grep -q "403" "$CURL_ERR_FILE" 2>/dev/null; then
    fail "GitHub API returned 403 Forbidden. This usually happens if you hit GitHub API rate limits. Try setting GITHUB_TOKEN environment variable (e.g. GITHUB_TOKEN=your_token ./install.sh)."
  fi
  if [ -s "$CURL_ERR_FILE" ]; then
    fail "Failed to fetch release info from GitHub API ($RELEASE_API_URL): $(cat "$CURL_ERR_FILE")"
  else
    fail "Failed to fetch release info from GitHub API ($RELEASE_API_URL)."
  fi
fi

DOWNLOAD_URL=$(
  printf '%s' "$RELEASE_JSON" \
    | tr ',' '\n' \
    | extract_asset_url \
    | grep "/Lumide-Linux-.*-$ARCH\.zip$" \
    | head -n 1 \
    || true
)

if [ -z "$DOWNLOAD_URL" ]; then
  DOWNLOAD_URL=$(
    printf '%s' "$RELEASE_JSON" \
      | tr ',' '\n' \
      | extract_asset_url \
      | grep "/Lumide-Linux-.*-$ARCH\.tar\.gz$" \
      | head -n 1 \
      || true
  )
fi

[ -n "$DOWNLOAD_URL" ] || fail "no Linux release asset found for architecture '$ARCH' in GitHub release '$VERSION'"

ASSET_NAME=$(basename "$DOWNLOAD_URL")

say "Downloading $DOWNLOAD_URL"
if ! curl -fL -H "User-Agent: Lumide-Installer" "$DOWNLOAD_URL" -o "$TMP_DIR/$ASSET_NAME"; then
  fail "Failed to download release asset from $DOWNLOAD_URL"
fi

say "Extracting archive"
case "$ASSET_NAME" in
  *.zip)
    need_cmd unzip
    unzip -q "$TMP_DIR/$ASSET_NAME" -d "$TMP_DIR"
    ;;
  *.tar.gz)
    need_cmd tar
    tar -xzf "$TMP_DIR/$ASSET_NAME" -C "$TMP_DIR"
    ;;
  *)
    fail "unsupported archive format: $ASSET_NAME"
    ;;
esac

PACKAGE_DIR="$TMP_DIR/$APP_NAME"
[ -x "$PACKAGE_DIR/$APP_NAME" ] || fail "archive does not contain $APP_NAME/$APP_NAME"
[ -f "$PACKAGE_DIR/share/applications/$APP_ID.desktop" ] || fail "archive is missing desktop metadata"
[ -f "$PACKAGE_DIR/share/icons/hicolor/512x512/apps/$APP_ID.png" ] || fail "archive is missing app icon"

mkdir -p "$(dirname "$INSTALL_ROOT")" "$BIN_DIR" "$DESKTOP_DIR" "$ICON_DIR"
rm -rf "$INSTALL_ROOT"
mv "$PACKAGE_DIR" "$INSTALL_ROOT"

ln -sfn "$INSTALL_ROOT/$APP_NAME" "$BIN_DIR/lumide"

# Patch the desktop file with absolute paths
# We use a temporary file to avoid issues with sed -i portability
sed -e "s|^Exec=.*|Exec=$INSTALL_ROOT/$APP_NAME %F|g" \
    -e "s|^Icon=.*|Icon=$ICON_DIR/$APP_ID.png|g" \
    "$INSTALL_ROOT/share/applications/$APP_ID.desktop" > "$TMP_DIR/$APP_ID.desktop"

install -m 0644 "$TMP_DIR/$APP_ID.desktop" "$DESKTOP_DIR/$APP_ID.desktop"
install -m 0644 "$INSTALL_ROOT/share/icons/hicolor/512x512/apps/$APP_ID.png" "$ICON_DIR/$APP_ID.png"

if command -v update-desktop-database >/dev/null 2>&1; then
  update-desktop-database "$DESKTOP_DIR" >/dev/null 2>&1 || true
fi

if command -v gtk-update-icon-cache >/dev/null 2>&1; then
  gtk-update-icon-cache "$XDG_DATA_HOME_DIR/icons/hicolor" >/dev/null 2>&1 || true
fi

say "Lumide installed to $INSTALL_ROOT"
say "CLI symlink: $BIN_DIR/lumide"

case ":$PATH:" in
  *":$BIN_DIR:"*) ;;
  *)
    say "Add $BIN_DIR to PATH to launch Lumide from the terminal."
    ;;
esac