#!/usr/bin/env bash
# install-ci-alias.sh — install a `ci` shell helper that runs the CI
# orchestrator as the ci-runner service user against the production venv.
#
# After install:  ci validate host   ==   sudo -u ci-runner \
#                   /opt/ci/venv/bin/python -m ci_orchestrator validate host
#
# Usage:
#   ./scripts/install-ci-alias.sh            # install into the current user's
#                                            # ~/.bashrc and ~/.zshrc (if present)
#   ./scripts/install-ci-alias.sh --system   # install system-wide via
#                                            # /etc/profile.d/ci-alias.sh (needs sudo)
#   ./scripts/install-ci-alias.sh --uninstall # remove the installed block
#
# Idempotent: re-running updates the block in place instead of duplicating it.
set -euo pipefail

PROD_PY="${CI_PROD_PYTHON:-/opt/ci/venv/bin/python}"
RUN_USER="${CI_RUN_USER:-ci-runner}"
MARK_BEGIN="# >>> ci-orchestrator alias >>>"
MARK_END="# <<< ci-orchestrator alias <<<"

log()  { printf '[install-ci-alias] %s\n' "$*"; }
die()  { printf '[install-ci-alias] ERROR: %s\n' "$*" >&2; exit 1; }

block() {
  # $1 (optional): path to a shell-completion file to source from the block.
  local cmpl="${1:-}"
  cat <<EOF
${MARK_BEGIN}
# Run the CI orchestrator as the ${RUN_USER} service user (production venv).
ci() { sudo -u ${RUN_USER} ${PROD_PY} -m ci_orchestrator "\$@"; }
# Same, but as the current user (no sudo) — handy for read-only commands.
ci-me() { ${PROD_PY} -m ci_orchestrator "\$@"; }
EOF
  [ -n "$cmpl" ] && printf '[ -f "%s" ] && source "%s"\n' "$cmpl" "$cmpl"
  printf '%s\n' "${MARK_END}"
}

# Generate a click shell-completion file for `ci`. Click's generated script
# calls the command (`ci`) to query completions, but `ci` is a sudo shell
# function — env vars don't survive sudo and `env VAR=x ci` can't call a
# function. Rewrite the query to call the venv python directly (read-only, no
# sudo) and drop zsh's `$+commands[ci]` guard (ci is a function, not on PATH).
gen_completion() {
  local out="$1" shell="$2"
  case "$shell" in
    zsh)
      # Self-load compinit if compdef isn't defined yet (so the file works even
      # without oh-my-zsh, or if sourced before compinit).
      printf '%s\n' 'if ! whence compdef >/dev/null 2>&1; then autoload -Uz compinit && compinit -u; fi' > "$out"
      _CI_COMPLETE=zsh_source "$PROD_PY" -m ci_orchestrator 2>/dev/null \
        | sed -e "s#_CI_COMPLETE=zsh_complete ci)#_CI_COMPLETE=zsh_complete ${PROD_PY} -m ci_orchestrator)#" \
              -e '/\$+commands\[ci\]/d' >> "$out" ;;
    bash)
      _CI_COMPLETE=bash_source "$PROD_PY" -m ci_orchestrator 2>/dev/null \
        | sed -e "s#_CI_COMPLETE=bash_complete \$1#_CI_COMPLETE=bash_complete ${PROD_PY} -m ci_orchestrator#" > "$out" ;;
    *) return 1 ;;
  esac
  [ -s "$out" ] || { rm -f "$out"; return 1; }
}

strip_block() {
  # Remove an existing marked block from $1 (in place). No-op if absent.
  local file="$1"
  [ -f "$file" ] || return 0
  if grep -qF "$MARK_BEGIN" "$file"; then
    # Delete everything between the markers, inclusive.
    sed -i "/$(printf '%s' "$MARK_BEGIN" | sed 's/[].[*^$/]/\\&/g')/,/$(printf '%s' "$MARK_END" | sed 's/[].[*^$/]/\\&/g')/d" "$file"
    # Drop a possible trailing blank line left behind.
    sed -i -e :a -e '/^\n*$/{$d;N;ba}' "$file" 2>/dev/null || true
  fi
}

install_into() {
  local file="$1" shell="" cmpl=""
  case "$file" in
    *.zshrc)  shell="zsh"  ;;
    *.bashrc) shell="bash" ;;
  esac
  if [ -n "$shell" ] && [ -x "$PROD_PY" ]; then
    cmpl="$HOME/.ci-completion.$shell"
    if gen_completion "$cmpl" "$shell"; then
      log "wrote $shell completion: $cmpl"
    else
      cmpl=""
      log "WARNING: could not generate $shell completion — skipped (alias still installed)."
    fi
  fi
  strip_block "$file"
  { printf '\n'; block "$cmpl"; } >> "$file"
  log "updated $file"
}

uninstall_from() {
  local file="$1"
  if [ -f "$file" ] && grep -qF "$MARK_BEGIN" "$file"; then
    strip_block "$file"
    log "removed block from $file"
  fi
}

main() {
  local mode="user" action="install"
  case "${1:-}" in
    --system)    mode="system" ;;
    --uninstall) action="uninstall" ;;
    "" )         ;;
    * )          die "unknown argument: $1 (use --system or --uninstall)" ;;
  esac

  # Sanity: warn (don't fail) if the production venv is missing.
  [ -x "$PROD_PY" ] || log "WARNING: $PROD_PY not found — alias installed anyway; fix the venv before use."

  if [ "$mode" = "system" ]; then
    local target="/etc/profile.d/ci-alias.sh"
    if [ "$action" = "uninstall" ]; then
      sudo rm -f "$target" && log "removed $target"
    else
      block | sudo tee "$target" >/dev/null
      sudo chmod 0644 "$target"
      log "installed $target (applies to all login shells)"
    fi
  else
    local files=()
    [ -f "$HOME/.bashrc" ] && files+=("$HOME/.bashrc")
    [ -f "$HOME/.zshrc" ]  && files+=("$HOME/.zshrc")
    # If neither exists, create ~/.bashrc so the alias lands somewhere.
    [ ${#files[@]} -eq 0 ] && files+=("$HOME/.bashrc")

    for f in "${files[@]}"; do
      if [ "$action" = "uninstall" ]; then uninstall_from "$f"; else install_into "$f"; fi
    done
  fi

  if [ "$action" = "install" ]; then
    log "done. Open a new shell, or run:  source ~/.bashrc"
    log "try:  ci validate host"
  else
    log "done. Open a new shell to drop the alias."
  fi
}

main "$@"