#!/bin/sh
# qinetic-cli one-line installer (ENG-1299).
#
#   curl -fsSL https://get.levr.now | sh      # production
#   curl -fsSL https://get.levr.now | sh      # staging
#
# Installs a per-platform tarball into ~/.qinetic/versions/<version>/, points
# ~/.qinetic/current at it, and writes a launcher to ~/.local/bin/qinetic.
#
# Requirements: Node >= 18 (no bundled runtime in v1) on a glibc Linux or macOS
# host. Alpine/musl is NOT supported in v1 (the native modules ship glibc-only
# prebuilds). curl OR wget, and tar.
#
# Environment overrides:
#   QINETIC_VERSION    pin a specific version instead of `latest`
#   QINETIC_BASE_URL   override the download origin (used by CI smoke tests and
#                      the staging copy; defaults to the production host below)
set -eu

# The staging deploy step rewrites this default to https://get.levr.now before
# uploading staging's copy. QINETIC_BASE_URL always takes precedence.
DEFAULT_BASE_URL="https://get.levr.now"
BASE_URL="${QINETIC_BASE_URL:-$DEFAULT_BASE_URL}"
# Strip any trailing slash so URL joins below are clean.
BASE_URL="${BASE_URL%/}"

QINETIC_HOME="${HOME}/.qinetic"
BIN_DIR="${HOME}/.local/bin"

err() { printf '\033[31merror:\033[0m %s\n' "$*" >&2; }
info() { printf '%s\n' "$*"; }

abort() {
  err "$1"
  exit 1
}

# ── 1. Detect OS / arch ─────────────────────────────────────────────────────
case "$(uname -s)" in
  Darwin) PLATFORM=darwin ;;
  Linux) PLATFORM=linux ;;
  *) abort "unsupported OS '$(uname -s)'. qinetic supports macOS and Linux only." ;;
esac

case "$(uname -m)" in
  arm64 | aarch64) ARCH=arm64 ;;
  x86_64 | amd64) ARCH=x64 ;;
  *) abort "unsupported architecture '$(uname -m)'. qinetic supports arm64 and x64." ;;
esac

# musl/Alpine is unsupported in v1 — the native prebuilds are glibc-only.
if [ "$PLATFORM" = linux ] && command -v ldd >/dev/null 2>&1; then
  if ldd --version 2>&1 | grep -qi musl; then
    abort "musl libc (Alpine) is not supported in v1. qinetic requires a glibc Linux (Ubuntu 18+, RHEL 7+, Debian 9+)."
  fi
fi

# ── 2. Require Node >= 18 ───────────────────────────────────────────────────
if ! command -v node >/dev/null 2>&1; then
  err "Node.js >= 18 is required but 'node' was not found on your PATH."
  err "Install Node 18+ from https://nodejs.org/en/download and re-run this installer."
  exit 1
fi
NODE_MAJOR=$(node -p 'process.versions.node.split(".")[0]' 2>/dev/null || echo 0)
if [ "$NODE_MAJOR" -lt 18 ] 2>/dev/null; then
  err "Node.js >= 18 is required (found $(node -v))."
  err "Upgrade Node from https://nodejs.org/en/download and re-run this installer."
  exit 1
fi

# ── Download helpers (curl or wget) ─────────────────────────────────────────
if command -v curl >/dev/null 2>&1; then
  fetch_stdout() { curl -fsSL "$1"; }
  fetch_file() { curl -fsSL "$1" -o "$2"; }
elif command -v wget >/dev/null 2>&1; then
  fetch_stdout() { wget -qO- "$1"; }
  fetch_file() { wget -qO "$2" "$1"; }
else
  abort "neither curl nor wget is available; cannot download qinetic."
fi

sha256_of() {
  if command -v sha256sum >/dev/null 2>&1; then
    sha256sum "$1" | cut -d' ' -f1
  else
    shasum -a 256 "$1" | cut -d' ' -f1
  fi
}

TMPDIR_INSTALL=$(mktemp -d 2>/dev/null || mktemp -d -t qinetic)
cleanup() { rm -rf "$TMPDIR_INSTALL"; }
trap cleanup EXIT INT TERM

# ── 3. Resolve version + artifact URL + expected sha256 ─────────────────────
if [ -n "${QINETIC_VERSION:-}" ]; then
  # Pinned version: construct the URL directly; read the sha from SHASUMS256.txt.
  VERSION="$QINETIC_VERSION"
  FILENAME="qinetic-${VERSION}-${PLATFORM}-${ARCH}.tar.gz"
  URL="${BASE_URL}/${VERSION}/${FILENAME}"
  info "Installing pinned qinetic ${VERSION} (${PLATFORM}-${ARCH})…"
  SHASUMS=$(fetch_stdout "${BASE_URL}/${VERSION}/SHASUMS256.txt") \
    || abort "could not fetch SHASUMS256.txt for version ${VERSION} from ${BASE_URL}."
  EXPECTED_SHA=$(printf '%s\n' "$SHASUMS" | awk -v f="$FILENAME" '$2 == f {print $1; exit}')
  [ -n "$EXPECTED_SHA" ] || abort "no checksum for ${FILENAME} in SHASUMS256.txt (is ${PLATFORM}-${ARCH} published for ${VERSION}?)."
else
  # Latest: read version + per-platform artifact from latest.json. Node is a
  # hard requirement (checked above), so parse with Node — no jq dependency.
  LATEST_FILE="${TMPDIR_INSTALL}/latest.json"
  fetch_file "${BASE_URL}/latest.json" "$LATEST_FILE" \
    || abort "could not fetch ${BASE_URL}/latest.json (is the installer host reachable?)."
  RESOLVED=$(node -e '
    const fs = require("fs");
    const [file, platform, arch] = process.argv.slice(1);
    let j;
    try { j = JSON.parse(fs.readFileSync(file, "utf8")); }
    catch (e) { console.error("latest.json is not valid JSON: " + e.message); process.exit(2); }
    const a = (j.artifacts || []).find((x) => x.platform === platform && x.arch === arch);
    if (!a) { console.error("no artifact for " + platform + "-" + arch + " in latest.json"); process.exit(3); }
    process.stdout.write([j.version || "", a.url || "", a.sha256 || ""].join("\n"));
  ' "$LATEST_FILE" "$PLATFORM" "$ARCH") \
    || abort "no qinetic build available for ${PLATFORM}-${ARCH}."
  VERSION=$(printf '%s\n' "$RESOLVED" | sed -n '1p')
  URL=$(printf '%s\n' "$RESOLVED" | sed -n '2p')
  EXPECTED_SHA=$(printf '%s\n' "$RESOLVED" | sed -n '3p')
  [ -n "$VERSION" ] && [ -n "$URL" ] || abort "latest.json is missing version or artifact URL."
  FILENAME="qinetic-${VERSION}-${PLATFORM}-${ARCH}.tar.gz"
  info "Installing qinetic ${VERSION} (${PLATFORM}-${ARCH})…"
fi

# Defense-in-depth: VERSION flows into filesystem paths (rm -rf / mkdir / tar)
# and the download URL. Reject anything that isn't a clean version token so a
# compromised latest.json / SHASUMS / QINETIC_VERSION can't path-traverse
# (e.g. `../../.bashrc`). Allows dev suffixes like `-local` / `-test`.
# (ENG-1299 code review F-003.)
if ! printf '%s' "$VERSION" | grep -qE '^[0-9A-Za-z][0-9A-Za-z._-]*$'; then
  abort "resolved version '${VERSION}' is not a valid version string; refusing to continue."
fi

# ── 4. Download + verify checksum ───────────────────────────────────────────
TARBALL="${TMPDIR_INSTALL}/${FILENAME}"
fetch_file "$URL" "$TARBALL" || abort "download failed: ${URL}"

if [ -n "$EXPECTED_SHA" ]; then
  # Guard against a truncated/garbled checksum line so the failure is a clear
  # "malformed checksum" rather than a confusing mismatch (F-009).
  if ! printf '%s' "$EXPECTED_SHA" | grep -qE '^[0-9a-fA-F]{64}$'; then
    abort "published checksum for ${FILENAME} is malformed (expected 64 hex chars): '${EXPECTED_SHA}'"
  fi
  ACTUAL_SHA=$(sha256_of "$TARBALL")
  if [ "$ACTUAL_SHA" != "$EXPECTED_SHA" ]; then
    err "Checksum verification failed for ${FILENAME}."
    err "  expected: ${EXPECTED_SHA}"
    err "  actual:   ${ACTUAL_SHA}"
    abort "refusing to install a tarball that does not match its published checksum."
  fi
  info "Checksum verified (sha256)."
else
  err "no checksum available for ${FILENAME}; refusing to install unverified."
  exit 1
fi

# ── 5. Extract to ~/.qinetic/versions/<version>/ ────────────────────────────
DEST="${QINETIC_HOME}/versions/${VERSION}"
rm -rf "$DEST"
mkdir -p "$DEST"
# Tarball top-level dir is `qinetic-<version>/`; strip it so DEST holds dist/.
tar -C "$DEST" --strip-components=1 -xzf "$TARBALL" \
  || abort "failed to extract ${FILENAME}."
[ -f "${DEST}/dist/cli.js" ] || abort "extracted tarball is missing dist/cli.js."

# ── 6. Point ~/.qinetic/current at this version ─────────────────────────────
ln -sfn "$DEST" "${QINETIC_HOME}/current"

# ── 7. Write launcher (idempotent) ──────────────────────────────────────────
mkdir -p "$BIN_DIR"
cat > "${BIN_DIR}/qinetic" <<'LAUNCHER'
#!/bin/sh
# qinetic launcher (managed by the qinetic installer — edits will be overwritten).
exec node "${HOME}/.qinetic/current/dist/cli.js" "$@"
LAUNCHER
chmod +x "${BIN_DIR}/qinetic"

# ── 8. PATH guidance ────────────────────────────────────────────────────────
case ":${PATH}:" in
  *":${BIN_DIR}:"*) ON_PATH=1 ;;
  *) ON_PATH=0 ;;
esac

# ── 9. Smoke check ──────────────────────────────────────────────────────────
SMOKE=$(node "${DEST}/dist/cli.js" --version 2>/dev/null || echo "")
if [ -z "$SMOKE" ]; then
  abort "installation completed but 'qinetic --version' did not run. Check that Node 18+ works on this host."
fi

info ""
info "qinetic ${SMOKE} installed → ${DEST}"
info "  launcher: ${BIN_DIR}/qinetic"
if [ "$ON_PATH" -eq 0 ]; then
  info ""
  info "⚠  ${BIN_DIR} is not on your PATH. Add this to your shell profile:"
  info "      export PATH=\"${BIN_DIR}:\$PATH\""
  info "   then restart your shell (or run the export now) and run: qinetic --help"
else
  info "  Run: qinetic --help"
fi