setup

#!/bin/sh
# brain.md installer — fan out the root-level skills/ to the global skills
# directory of each agent runtime you choose (symlinks). Agent-agnostic, zero
# dependencies, idempotent.
#
# Tools (skills + the brain CLI) install globally, once, across all projects.
# This NEVER touches any project's brain knowledge — that is per-project state,
# created on demand by the brain-setup skill and never managed from here.
#
# Usage: ./setup [--yes|-y]
#   --yes, -y   non-interactive: install into every detected runtime without
#               asking (for CI). Default is to ask about each runtime, y/N.
set -eu

ASSUME_YES=0
for arg in "$@"; do
  case "$arg" in
    --yes|-y) ASSUME_YES=1 ;;
    *) echo "setup: unknown option '$arg'" >&2; exit 2 ;;
  esac
done

# Resolve the directory this script lives in (the repo root).
SCRIPT_DIR=$(CDPATH= cd -- "$(dirname -- "$0")" && pwd -P)
SRC="$SCRIPT_DIR/skills"

if [ ! -d "$SRC" ]; then
  echo "setup: no skills/ directory next to this installer ($SRC)" >&2
  exit 1
fi

# Discover every skill bundle under skills/ (any directory with a SKILL.md),
# so newly added skills are installed automatically without editing this list.
SKILLS=""
for skill_dir in "$SRC"/*/; do
  [ -f "${skill_dir}SKILL.md" ] || continue
  SKILLS="$SKILLS $(basename "$skill_dir")"
done

if [ -z "$SKILLS" ]; then
  echo "setup: no skill bundles found under $SRC" >&2
  exit 1
fi

print_logo() {
  cat <<'LOGO'

  ██████╗ ██████╗  █████╗ ██╗███╗   ██╗   ███╗   ███╗██████╗
  ██╔══██╗██╔══██╗██╔══██╗██║████╗  ██║   ████╗ ████║██╔══██╗
  ██████╔╝██████╔╝███████║██║██╔██╗ ██║   ██╔████╔██║██║  ██║
  ██╔══██╗██╔══██╗██╔══██║██║██║╚██╗██║   ██║╚██╔╝██║██║  ██║
  ██████╔╝██║  ██║██║  ██║██║██║ ╚████║██╗██║ ╚═╝ ██║██████╔╝
  ╚═════╝ ╚═╝  ╚═╝╚═╝  ╚═╝╚═╝╚═╝  ╚═══╝╚═╝╚═╝     ╚═╝╚═════╝

  Open Project Brain Standard — install-first, agent-agnostic toolkit.

LOGO
}

# Ask a y/N question. Returns 0 for yes, 1 for no. Honours --yes; reads the
# answer from stdin (a terminal when run interactively, or piped input), and
# defaults to no when stdin is closed/empty.
ask() {
  if [ "$ASSUME_YES" -eq 1 ]; then
    return 0
  fi
  printf '%s [y/N] ' "$1"
  read -r reply || reply=""
  case "$reply" in
    [yY]|[yY][eE][sS]) return 0 ;;
    *) return 1 ;;
  esac
}

print_logo

# Candidate agent runtimes: "<label>:<parent-config-dir>:<skills-dir>". A runtime
# counts as detected only when its parent config dir exists.
CANDIDATES="Claude:$HOME/.claude:$HOME/.claude/skills Codex:$HOME/.codex:$HOME/.codex/skills OpenCode:$HOME/.config/opencode:$HOME/.config/opencode/skills Cursor:$HOME/.cursor:$HOME/.cursor/skills Pi:$HOME/.pi/agent:$HOME/.pi/agent/skills"

DETECTED=""
echo "Detecting supported runtimes:"
for entry in $CANDIDATES; do
  label=${entry%%:*}
  rest=${entry#*:}
  parent=${rest%%:*}
  if [ -d "$parent" ]; then
    echo "  [found]   $label ($parent)"
    DETECTED="$DETECTED $entry"
  else
    echo "  [missing] $label ($parent)"
  fi
done
echo

if [ -z "$DETECTED" ]; then
  echo "setup: no agent config directories detected (looked for ~/.claude, ~/.codex, ~/.config/opencode, ~/.cursor, ~/.pi/agent)." >&2
  echo "setup: create one, or symlink skills/ manually, then re-run." >&2
  exit 1
fi

# Manifest of links we create, so uninstall can clean up exactly what we installed.
STATE_DIR="${XDG_STATE_HOME:-$HOME/.local/state}/brain.md"
MANIFEST="$STATE_DIR/installed-links"
mkdir -p "$STATE_DIR"
: > "$MANIFEST.tmp"

installed_any=0

for entry in $DETECTED; do
  label=${entry%%:*}
  rest=${entry#*:}
  parent=${rest%%:*}
  dest=${rest#*:}

  if ! ask "Install brain.md skills into $label ($parent)?"; then
    echo "setup: skipped $label."
    continue
  fi

  mkdir -p "$dest"
  for skill in $SKILLS; do
    target="$dest/$skill"
    source="$SRC/$skill"

    if [ -L "$target" ]; then
      rm -f "$target"
    elif [ -e "$target" ]; then
      # A real (non-symlink) directory is in the way — back it up once, don't destroy it.
      backup="$target.pre-brain.bak"
      if [ -e "$backup" ]; then
        echo "setup: $target exists and $backup is taken; skipping (resolve manually)" >&2
        continue
      fi
      mv "$target" "$backup"
      echo "setup: moved existing $target -> $backup"
    fi

    ln -s "$source" "$target"
    printf '%s\n' "$target" >> "$MANIFEST.tmp"
    echo "setup: linked $target -> $source"
    installed_any=1
  done
done

# Merge with any previously recorded links (dedup), so the manifest stays complete.
if [ -f "$MANIFEST" ]; then
  cat "$MANIFEST" >> "$MANIFEST.tmp"
fi
sort -u "$MANIFEST.tmp" > "$MANIFEST"
rm -f "$MANIFEST.tmp"

if [ "$installed_any" -eq 0 ]; then
  echo "setup: nothing installed (no runtime confirmed)."
  exit 0
fi

echo
echo "setup: done. Manifest: $MANIFEST"
echo "setup: run the brain-setup skill inside a project to scaffold its BRAIN.md + brain/."