skills/install.sh

#!/usr/bin/env bash
# install.sh — bootstrap installer for the skills library.
#
# Usage (one-liner, hosts without Task):
#   curl -fsSL https://git.d-ma.be/mathias/skills/raw/branch/main/install.sh | bash
#
# Pinned to a specific tag:
#   SKILLS_REF=v0.1.0 bash install.sh
#
# Idempotent: re-running pulls the latest changes for the configured ref
# (default: main) and re-wires symlinks. Existing correct links are
# left alone; mismatched ones are replaced.

set -euo pipefail

REPO_URL="${SKILLS_REPO_URL:-https://git.d-ma.be/mathias/skills.git}"
REF="${SKILLS_REF:-main}"
CHECKOUT_DIR="${SKILLS_CHECKOUT_DIR:-$HOME/.local/share/skills}"
CLAUDE_GLOBAL_DIR="${CLAUDE_SKILLS_DIR:-$HOME/.claude/skills}"
CRUSH_DIR="${CRUSH_SKILLS_DIR:-$HOME/.config/crush/skills}"
ANTIGRAVITY_DIR="${ANTIGRAVITY_SKILLS_DIR:-$HOME/.gemini/antigravity/skills}"
VIBE_SKILLS_DIR="${VIBE_SKILLS_DIR:-$HOME/.vibe/skills}"

log() { printf '[skills] %s\n' "$*"; }

ensure_checkout() {
  if [ -d "$CHECKOUT_DIR/.git" ]; then
    log "updating $CHECKOUT_DIR"
    git -C "$CHECKOUT_DIR" fetch --tags --quiet
    git -C "$CHECKOUT_DIR" checkout --quiet "$REF"
    if git -C "$CHECKOUT_DIR" symbolic-ref -q HEAD >/dev/null; then
      # on a branch — fast-forward
      git -C "$CHECKOUT_DIR" pull --ff-only --quiet
    fi
  else
    log "cloning $REPO_URL into $CHECKOUT_DIR (ref=$REF)"
    mkdir -p "$(dirname "$CHECKOUT_DIR")"
    git clone --quiet "$REPO_URL" "$CHECKOUT_DIR"
    git -C "$CHECKOUT_DIR" checkout --quiet "$REF"
  fi
}

list_skills() {
  # Every top-level entry that isn't a known meta file.
  (cd "$CHECKOUT_DIR" && ls -1) | grep -Ev '^(Taskfile\.yml|install\.sh|README\.md|SKILLS_INDEX\.md|\.gitea|\.git)$' || true
}

link_skill() {
  # link_skill <target_dir> <skill_name>
  local target_dir="$1"
  local skill="$2"
  local target="$CHECKOUT_DIR/$skill"
  local link="$target_dir/$skill"

  if [ -L "$link" ] || [ -e "$link" ]; then
    local current
    current=$(readlink "$link" 2>/dev/null || true)
    if [ "$current" = "$target" ]; then
      return
    fi
    rm -rf "$link"
  fi
  ln -s "$target" "$link"
  log "linked $link → $target"
}

wire_claude_global() {
  mkdir -p "$CLAUDE_GLOBAL_DIR"
  while IFS= read -r skill; do
    [ -n "$skill" ] || continue
    link_skill "$CLAUDE_GLOBAL_DIR" "$skill"
  done < <(list_skills)
}

wire_crush() {
  # Crush reads skills from ~/.config/crush/skills/<name>/SKILL.md.
  # Pre-creating the dir is cheap even when Crush isn't installed.
  mkdir -p "$CRUSH_DIR"
  while IFS= read -r skill; do
    [ -n "$skill" ] || continue
    link_skill "$CRUSH_DIR" "$skill"
  done < <(list_skills)
}

wire_antigravity() {
  # Antigravity (Google's VS Code extension) reads global skills from
  # ~/.gemini/antigravity/skills/<name>/SKILL.md. Our SKILL.md files
  # already carry the required `name` + `description` YAML frontmatter,
  # so symlinks are sufficient — no manifest translation step.
  mkdir -p "$ANTIGRAVITY_DIR"
  while IFS= read -r skill; do
    [ -n "$skill" ] || continue
    link_skill "$ANTIGRAVITY_DIR" "$skill"
  done < <(list_skills)
}

wire_claude_repo() {
  # Only wire per-repo when invoked from inside a git repo and it isn't
  # the skills repo itself.
  if ! git rev-parse --show-toplevel >/dev/null 2>&1; then
    return
  fi
  local repo
  repo=$(git rev-parse --show-toplevel)
  if [ "$repo" = "$CHECKOUT_DIR" ]; then
    return
  fi
  local target_dir="$repo/.claude/skills"
  mkdir -p "$target_dir"
  while IFS= read -r skill; do
    [ -n "$skill" ] || continue
    link_skill "$target_dir" "$skill"
  done < <(list_skills)
}

wire_vibe() {
  # Mistral Vibe reads a flat ~/.vibe/skills/<name>.md — link the SKILL.md
  # file directly (not the skill directory, as the other harnesses do).
  mkdir -p "$VIBE_SKILLS_DIR"
  while IFS= read -r skill; do
    [ -n "$skill" ] || continue
    local target="$CHECKOUT_DIR/$skill/SKILL.md"
    [ -f "$target" ] || continue
    local link="$VIBE_SKILLS_DIR/$skill.md"
    if [ -L "$link" ] || [ -e "$link" ]; then
      local current
      current=$(readlink "$link" 2>/dev/null || true)
      if [ "$current" = "$target" ]; then
        continue
      fi
      rm -rf "$link"
    fi
    ln -s "$target" "$link"
    log "linked $link → $target"
  done < <(list_skills)
}

main() {
  ensure_checkout
  wire_claude_global
  wire_claude_repo
  wire_crush
  wire_antigravity
  wire_vibe
  log "done — $(list_skills | wc -l | tr -d ' ') skill(s) wired at ref=$REF"
}

main "$@"