#!/usr/bin/env bash
set -euo pipefail

# Check which skills from the source repo are missing from the active Claude profile.

DEFAULT_SKILLS_REPO="$HOME/dev/claude/projects/custom-claude-skills/skills"

usage() {
    cat <<'EOF'
Usage: check-skills [OPTIONS] [SKILLS_REPO]

Check which skills from the custom-claude-skills repository are missing
from the active Claude Code profile's skills directory.

Arguments:
  SKILLS_REPO    Path to skills source directory
                 (default: ~/dev/claude/projects/custom-claude-skills/skills)

Options:
  --profile DIR  Override Claude profile directory
                 (default: $CLAUDE_CONFIG_DIR or ~/.claude)
  --dryrun, -n   Accepted for convention compliance (script is read-only)
  --help, -h     Show this help
EOF
}

# Colours
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
CYAN='\033[0;36m'
RED='\033[0;31m'
BOLD='\033[1m'
NC='\033[0m'

# Parse args
profile_dir=""
skills_repo=""

while [[ $# -gt 0 ]]; do
    case "$1" in
        --profile) profile_dir="$2"; shift 2 ;;
        --dryrun|-n) shift ;;
        --help|-h) usage; exit 0 ;;
        -*) echo "Unknown option: $1" >&2; usage >&2; exit 1 ;;
        *) skills_repo="$1"; shift ;;
    esac
done

skills_repo="${skills_repo:-$DEFAULT_SKILLS_REPO}"
profile_dir="${profile_dir:-${CLAUDE_CONFIG_DIR:-$HOME/.claude}}"
profile_skills="$profile_dir/skills"

# Validate source
if [[ ! -d "$skills_repo" ]]; then
    echo -e "${RED}ERROR${NC} Skills source directory not found: $skills_repo" >&2
    exit 1
fi

# Display paths (use ~ shorthand for readability)
display_profile="${profile_skills/#$HOME/~}"
display_source="${skills_repo/#$HOME/~}"
echo -e "${BOLD}Profile:${NC} $display_profile"
echo -e "${BOLD}Source:${NC}  $display_source"
echo ""

linked=0
missing=0
stale=0
orphan=0

# Check each source skill
for skill_dir in "$skills_repo"/*/; do
    [[ -d "$skill_dir" ]] || continue
    [[ -f "$skill_dir/SKILL.md" ]] || continue

    skill_name="$(basename "$skill_dir")"
    target="$profile_skills/$skill_name"

    if [[ -L "$target" ]]; then
        actual="$(readlink -f "$target" 2>/dev/null || echo "BROKEN")"
        expected="$(readlink -f "$skill_dir")"
        if [[ "$actual" == "$expected" ]]; then
            echo -e "  ${GREEN}LINKED${NC}   $skill_name"
            linked=$((linked + 1))
        else
            echo -e "  ${YELLOW}STALE${NC}    $skill_name (points to $actual)"
            stale=$((stale + 1))
        fi
    elif [[ -e "$target" ]]; then
        echo -e "  ${YELLOW}STALE${NC}    $skill_name (non-symlink exists)"
        stale=$((stale + 1))
    else
        echo -e "  ${YELLOW}MISSING${NC}  $skill_name"
        missing=$((missing + 1))
    fi
done

# Check for orphans in profile
if [[ -d "$profile_skills" ]]; then
    for entry in "$profile_skills"/*/; do
        [[ -d "$entry" || -L "$entry" ]] || continue
        entry_name="$(basename "$entry")"
        if [[ ! -d "$skills_repo/$entry_name" ]]; then
            echo -e "  ${CYAN}ORPHAN${NC}   $entry_name (not in source repo)"
            orphan=$((orphan + 1))
        fi
    done
fi

echo ""
echo -e "Summary: ${GREEN}$linked linked${NC}, ${YELLOW}$missing missing${NC}, ${YELLOW}$stale stale${NC}, ${CYAN}$orphan orphan${NC}"

if [[ $missing -gt 0 || $stale -gt 0 ]]; then
    echo ""
    echo "Run 'install.sh' from the custom-claude-skills repo to fix missing/stale skills."
    exit 1
fi

exit 0