#!/usr/bin/env bash
# Installs the pinned CI linters into "$TOOLS_DIR/bin" and echoes that directory
# on stdout, so callers can do:
#
#   export PATH="$(bash .gitea/workflows/install-ci-tools.sh kubeconform shellcheck):$PATH"
#
# Versions come from tool-versions.env next to this script and are kept fresh by
# Renovate. Re-running is cheap: an already-installed tool at the pinned version
# is left alone.
set -euo pipefail

here="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
# shellcheck source=tool-versions.env
. "$here/tool-versions.env"

TOOLS_DIR="${TOOLS_DIR:-${RUNNER_TEMP:-/tmp}/homelab-tools}"
BIN_DIR="$TOOLS_DIR/bin"
mkdir -p "$BIN_DIR"

arch="$(uname -m)"
# Upstream projects disagree on arch spelling: kubeconform and actionlint use
# Go names (amd64/arm64), shellcheck uses uname names (x86_64/aarch64).
case "$arch" in
  x86_64 | amd64)
    goarch=amd64
    sharch=x86_64
    ;;
  aarch64 | arm64)
    goarch=arm64
    sharch=aarch64
    ;;
  *)
    echo "install-ci-tools: unsupported architecture: $arch" >&2
    exit 1
    ;;
esac

fetch() {
  # fetch <url> <dest>
  if command -v curl >/dev/null 2>&1; then
    curl -sSLf --retry 3 -o "$2" "$1"
  elif command -v wget >/dev/null 2>&1; then
    wget -q -O "$2" "$1"
  else
    echo "install-ci-tools: neither curl nor wget is available" >&2
    exit 1
  fi
}

# installed_version <command>
# Prints the version of an already-installed tool, or nothing. Each tool spells
# its version flag differently, hence the case.
installed_version() {
  local out
  case "$1" in
    kubeconform) out="$("$1" -v 2>/dev/null | head -1 || true)" ;;
    *) out="$("$1" --version 2>/dev/null | head -1 || true)" ;;
  esac
  printf '%s' "$out"
}

# at_version <command> <expected>
at_version() {
  case "$(installed_version "$1")" in
    *"$2"*) return 0 ;;
    *) return 1 ;;
  esac
}

install_kubeconform() {
  if at_version kubeconform "v${KUBECONFORM_VERSION}"; then
    return 0
  fi
  local tmp
  tmp="$(mktemp -d)"
  fetch "https://github.com/yannh/kubeconform/releases/download/v${KUBECONFORM_VERSION}/kubeconform-linux-${goarch}.tar.gz" \
    "$tmp/kubeconform.tar.gz"
  tar -xzf "$tmp/kubeconform.tar.gz" -C "$tmp" kubeconform
  install -m 0755 "$tmp/kubeconform" "$BIN_DIR/kubeconform"
  rm -rf "$tmp"
}

install_shellcheck() {
  if at_version shellcheck "${SHELLCHECK_VERSION}"; then
    return 0
  fi
  local tmp
  tmp="$(mktemp -d)"
  fetch "https://github.com/koalaman/shellcheck/releases/download/v${SHELLCHECK_VERSION}/shellcheck-v${SHELLCHECK_VERSION}.linux.${sharch}.tar.xz" \
    "$tmp/shellcheck.tar.xz"
  tar -xJf "$tmp/shellcheck.tar.xz" -C "$tmp" --strip-components=1 "shellcheck-v${SHELLCHECK_VERSION}/shellcheck"
  install -m 0755 "$tmp/shellcheck" "$BIN_DIR/shellcheck"
  rm -rf "$tmp"
}

install_actionlint() {
  if at_version actionlint "${ACTIONLINT_VERSION}"; then
    return 0
  fi
  local tmp
  tmp="$(mktemp -d)"
  fetch "https://github.com/rhysd/actionlint/releases/download/v${ACTIONLINT_VERSION}/actionlint_${ACTIONLINT_VERSION}_linux_${goarch}.tar.gz" \
    "$tmp/actionlint.tar.gz"
  tar -xzf "$tmp/actionlint.tar.gz" -C "$tmp" actionlint
  install -m 0755 "$tmp/actionlint" "$BIN_DIR/actionlint"
  rm -rf "$tmp"
}

wanted=("$@")
if [ "${#wanted[@]}" -eq 0 ]; then
  wanted=(kubeconform shellcheck actionlint)
fi

for tool in "${wanted[@]}"; do
  case "$tool" in
    kubeconform) install_kubeconform ;;
    shellcheck) install_shellcheck ;;
    actionlint) install_actionlint ;;
    *)
      echo "install-ci-tools: unknown tool: $tool" >&2
      exit 1
      ;;
  esac
done

printf '%s\n' "$BIN_DIR"