#!/bin/sh
# PenguinHarness one-line installer.
#
#   curl -fsSL https://github.com/Prism-Shadow/penguin-harness/releases/latest/download/install.sh | sh
#
# Options:
#   PENGUIN_VERSION=vX.Y.Z    pin a version (same as --version vX.Y.Z); default is the latest Release
#   PENGUIN_INSTALL_DIR=<dir> install dir; default ~/.penguin
#   PENGUIN_ARCHIVE=<file>    install a local Release archive without network access (same as --archive <file>)
#   --universal               install the universal package (no bundled Node runtime; needs system Node >= 24)
#
# The data dir (~/.penguin/data) sits under the install home but is never touched by reinstall/upgrade (which only replace bin/lib/web/node).
#
# Docs: https://penguin.ooo/docs/installation
set -eu

REPO="https://github.com/Prism-Shadow/penguin-harness"
VERSION="${PENGUIN_VERSION:-}"
INSTALL_DIR="${PENGUIN_INSTALL_DIR:-$HOME/.penguin}"
BIN_DIR="$HOME/.local/bin"
UNIVERSAL=0
ARCHIVE="${PENGUIN_ARCHIVE:-}"

fail() {
  echo "error: $1" >&2
  exit 1
}

# --- Parse args (also passable via curl | sh -s -- --universal) ---
while [ $# -gt 0 ]; do
  case "$1" in
    --version)
      [ $# -ge 2 ] || fail "--version requires a value (e.g. --version v1.0.0)"
      VERSION="$2"
      shift 2
      ;;
    --universal)
      UNIVERSAL=1
      shift
      ;;
    --archive)
      [ $# -ge 2 ] || fail "--archive requires a path to a Release archive"
      ARCHIVE="$2"
      shift 2
      ;;
    *)
      fail "unknown option: $1"
      ;;
  esac
done

# --- Detect platform: Linux/Darwin x64/arm64; other platforms should use the universal package ---
TARGET="universal"
ASSET="penguin-universal.tar.gz"
if [ "$UNIVERSAL" -eq 0 ]; then
  case "$(uname -s)" in
    Linux) os="linux" ;;
    Darwin) os="darwin" ;;
    *) fail "unsupported OS: $(uname -s). Install Node.js >= 24, then re-run with --universal." ;;
  esac
  case "$(uname -m)" in
    x86_64) arch="x64" ;;
    aarch64 | arm64) arch="arm64" ;;
    *) fail "unsupported architecture: $(uname -m). Install Node.js >= 24, then re-run with --universal." ;;
  esac
  TARGET="$os-$arch"
  ASSET="penguin-$TARGET.tar.gz"
fi

if [ -n "$ARCHIVE" ] && [ -n "$VERSION" ]; then
  fail "--archive/PENGUIN_ARCHIVE cannot be combined with --version/PENGUIN_VERSION"
fi

# --- Universal package precheck: system Node >= 24 (platform packages bundle the runtime, so exempt) ---
if [ "$UNIVERSAL" -eq 1 ]; then
  command -v node >/dev/null 2>&1 \
    || fail "the universal package needs Node.js >= 24 on PATH (none found)."
  node_version="$(node --version)" # e.g. v24.18.0
  v="${node_version#v}"
  major="${v%%.*}"
  if [ "$major" -lt 24 ]; then
    fail "the universal package needs Node.js >= 24, found $node_version."
  fi
fi

TMP="$(mktemp -d)"
STAGING=""
OLD_DIR=""
SWAP_ACTIVE=0
MOVED_OLD=""
MOVED_NEW=""

rollback_install() {
  rollback_failed=0
  for d in $MOVED_NEW; do
    rm -rf "$INSTALL_DIR/$d" || rollback_failed=1
  done
  for d in $MOVED_OLD; do
    if [ -e "$OLD_DIR/$d" ]; then
      mv "$OLD_DIR/$d" "$INSTALL_DIR/$d" || rollback_failed=1
    fi
  done
  if [ "$rollback_failed" -ne 0 ]; then
    echo "error: automatic rollback was incomplete; previous files remain in $OLD_DIR" >&2
    return 1
  fi
  echo "Previous PenguinHarness installation restored." >&2
}

cleanup() {
  status=$?
  trap - EXIT HUP INT TERM
  set +e
  if [ "$SWAP_ACTIVE" -eq 1 ]; then
    rollback_install
  fi
  rm -rf "$TMP"
  [ -z "$STAGING" ] || rm -rf "$STAGING"
  [ -z "$OLD_DIR" ] || rm -rf "$OLD_DIR"
  exit "$status"
}

trap cleanup EXIT
trap 'exit 129' HUP
trap 'exit 130' INT
trap 'exit 143' TERM

# --- Resolve local/offline archive or download from GitHub. ---
LOCAL_ARCHIVE=0
HAVE_SHA=0
if [ -n "$ARCHIVE" ]; then
  [ -f "$ARCHIVE" ] || fail "local archive not found: $ARCHIVE"
  archive_name="${ARCHIVE##*/}"
  archive_dir="$(CDPATH= cd "$(dirname "$ARCHIVE")" && pwd)"
  ARCHIVE_PATH="$archive_dir/$archive_name"
  SHA_PATH="$ARCHIVE_PATH.sha256"
  if [ ! -f "$SHA_PATH" ] && [ "$archive_name" != "$ASSET" ] && [ -f "$archive_dir/$ASSET.sha256" ]; then
    SHA_PATH="$archive_dir/$ASSET.sha256"
  fi
  [ -f "$SHA_PATH" ] || fail "offline checksum file not found: $SHA_PATH"
  ARCHIVE_NAME="$archive_name"
  LOCAL_ARCHIVE=1
  HAVE_SHA=1
  echo "Using local archive $ARCHIVE_PATH ..."
else
  if [ -n "$VERSION" ]; then
    BASE_URL="$REPO/releases/download/$VERSION"
  else
    BASE_URL="$REPO/releases/latest/download"
  fi
  ARCHIVE_PATH="$TMP/$ASSET"
  SHA_PATH="$TMP/$ASSET.sha256"
  ARCHIVE_NAME="$ASSET"
  echo "Downloading $BASE_URL/$ASSET ..."
  curl -fSL --progress-bar "$BASE_URL/$ASSET" -o "$ARCHIVE_PATH" \
    || fail "download failed. Check the version tag and your network, then retry."
  if curl -fsSL "$BASE_URL/$ASSET.sha256" -o "$SHA_PATH" 2>/dev/null; then
    HAVE_SHA=1
  fi
fi

# --- SHA256 verify: mandatory offline; online keeps the existing warn-and-skip fallback. ---
if [ "$HAVE_SHA" -eq 1 ]; then
  expected="$(awk 'NR == 1 { print $1 }' "$SHA_PATH" | tr 'A-F' 'a-f')"
  [ -n "$expected" ] || fail "checksum file is empty or malformed: $SHA_PATH"
  if command -v sha256sum >/dev/null 2>&1; then
    actual="$(sha256sum "$ARCHIVE_PATH" | awk '{ print $1 }')"
  elif command -v shasum >/dev/null 2>&1; then
    actual="$(shasum -a 256 "$ARCHIVE_PATH" | awk '{ print $1 }')"
  else
    if [ "$LOCAL_ARCHIVE" -eq 1 ]; then
      fail "offline installation requires sha256sum or shasum for checksum verification"
    fi
    actual=""
    echo "warning: sha256sum/shasum not found; skipping checksum verification." >&2
  fi
  if [ -n "$actual" ]; then
    [ "$actual" = "$expected" ] || fail "checksum mismatch for $ASSET."
    echo "Checksum OK."
  fi
else
  echo "warning: checksum file not available; skipping verification." >&2
fi

# --- Extract and validate in staging before touching the current install. The final same-filesystem
#    swap keeps the previous dirs in .old.$$ until the installed command runs successfully; any
#    move or launch failure restores them automatically. The data dir is never part of the swap. ---
tar -xzf "$ARCHIVE_PATH" -C "$TMP"
[ -d "$TMP/penguin" ] || fail "unexpected archive layout: top-level penguin/ missing."
MANIFEST_PATH="$TMP/penguin/package-manifest.json"
if [ -f "$MANIFEST_PATH" ]; then
  manifest_target="$(sed -n 's/.*"target"[[:space:]]*:[[:space:]]*"\([^"]*\)".*/\1/p' "$MANIFEST_PATH" | head -n 1)"
  [ -n "$manifest_target" ] || fail "package manifest is malformed: target missing."
  [ "$manifest_target" = "$TARGET" ] \
    || fail "package target mismatch: expected $TARGET, found $manifest_target."
elif [ "$LOCAL_ARCHIVE" -eq 1 ] && [ "$ARCHIVE_NAME" != "$ASSET" ]; then
  fail "a renamed local archive must contain package-manifest.json; use the original filename for legacy packages."
fi
mkdir -p "$INSTALL_DIR"
STAGING="$INSTALL_DIR/.staging.$$"
OLD_DIR="$INSTALL_DIR/.old.$$"
rm -rf "$STAGING"
rm -rf "$OLD_DIR"
mkdir -p "$STAGING"
for d in bin lib web node; do
  if [ -e "$TMP/penguin/$d" ]; then
    mv "$TMP/penguin/$d" "$STAGING/$d"
  fi
done
[ -x "$STAGING/bin/penguin" ] || fail "unexpected archive layout: bin/penguin missing."

# The launcher resolves lib/, web/ and node/ relative to itself, so staging is a faithful
# preflight that catches macOS execution policy and runtime/package failures before replacement.
if candidate_version="$("$STAGING/bin/penguin" --version)"; then
  [ -n "$candidate_version" ] || fail "candidate PenguinHarness returned an empty version."
else
  candidate_status=$?
  fail "candidate PenguinHarness failed to run (exit status $candidate_status). See the error above."
fi

mkdir -p "$OLD_DIR"
SWAP_ACTIVE=1
for d in bin lib web node; do
  if [ -e "$INSTALL_DIR/$d" ]; then
    if mv "$INSTALL_DIR/$d" "$OLD_DIR/$d"; then
      MOVED_OLD="$MOVED_OLD $d"
    else
      fail "could not move the existing $d directory aside; the previous installation will be restored."
    fi
  fi
done
for d in bin lib web node; do
  if [ -e "$STAGING/$d" ]; then
    if mv "$STAGING/$d" "$INSTALL_DIR/$d"; then
      MOVED_NEW="$MOVED_NEW $d"
    else
      fail "could not install the new $d directory; the previous installation will be restored."
    fi
  fi
done
[ -x "$INSTALL_DIR/bin/penguin" ] || fail "install incomplete: $INSTALL_DIR/bin/penguin missing."

# Verify again from the final path before deleting the backup. Keep stderr visible so platform
# policy, permission and runtime errors are not disguised as an "unknown" version.
if installed_version="$("$INSTALL_DIR/bin/penguin" --version)"; then
  [ -n "$installed_version" ] || fail "installed PenguinHarness returned an empty version."
else
  version_status=$?
  fail "installed PenguinHarness failed to run (exit status $version_status); the previous installation will be restored. See the error above."
fi

SWAP_ACTIVE=0
if ! rm -rf "$OLD_DIR"; then
  echo "warning: could not remove the previous installation backup at $OLD_DIR" >&2
fi
OLD_DIR=""
rm -rf "$STAGING"
STAGING=""

# --- Symlink into ~/.local/bin and check PATH only after the install is known to work. ---
mkdir -p "$BIN_DIR"
ln -sf "$INSTALL_DIR/bin/penguin" "$BIN_DIR/penguin"
PATH_MISSING=0
case ":$PATH:" in
  *":$BIN_DIR:"*) ;;
  *) PATH_MISSING=1 ;;
esac

echo ""
echo "PenguinHarness $installed_version installed to $INSTALL_DIR"
if [ "$PATH_MISSING" -eq 1 ]; then
  echo ""
  echo "note: installation succeeded, but $BIN_DIR is not on your PATH. Add it to your shell profile:"
  case "${SHELL:-}" in
    */zsh) echo "  echo 'export PATH=\"\$HOME/.local/bin:\$PATH\"' >> ~/.zshrc && source ~/.zshrc" ;;
    */bash) echo "  echo 'export PATH=\"\$HOME/.local/bin:\$PATH\"' >> ~/.bashrc && source ~/.bashrc" ;;
    */fish) echo "  fish_add_path \$HOME/.local/bin" ;;
    *) echo "  export PATH=\"\$HOME/.local/bin:\$PATH\"" ;;
  esac
fi
echo ""
echo "Get started:"
echo "  penguin --help    # all commands"
echo "  penguin web       # start the Web UI at http://127.0.0.1:7364 (initial login: admin / penguin-2026)"
echo "  penguin server    # headless server (PORT / HOST to override)"