#!/usr/bin/env bash
# Bridge SessionStart hook. Injects skills/using-bridge/SKILL.md into the
# LLM system prompt at session start and appends a one-line health summary.

set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
SKILL_FILE="$SCRIPT_DIR/../skills/using-bridge/SKILL.md"

if [ ! -f "$SKILL_FILE" ]; then
  printf '{"hookSpecificOutput":{"hookEventName":"SessionStart","additionalContext":""}}\n'
  exit 0
fi

SKILL_BODY="$(awk 'BEGIN{fm=0} /^---$/{fm++; next} fm>=2{print}' "$SKILL_FILE")"

HEALTH=""
if [ -f "docs.config.yaml" ]; then
  KB_FILE="bridge-ds/knowledge-base/registries/components.json"
  if [ -f "$KB_FILE" ]; then
    COMP_COUNT="$(python3 -c "
import json, sys
try:
    with open('$KB_FILE') as f:
        print(len(json.load(f).get('components', [])))
except Exception:
    print('?')
" 2>/dev/null || echo "?")"
    HEALTH="◆ Bridge: KB ready · $COMP_COUNT components"
  else
    HEALTH="◆ Bridge: scaffolded but not yet extracted · run \"setup bridge\""
  fi
else
  HEALTH="◆ Bridge: not set up yet · run \"setup bridge\" to initialize"
fi

COMBINED="$SKILL_BODY"
if [ -n "$HEALTH" ]; then
  COMBINED="$COMBINED

---

$HEALTH"
fi

printf '{"hookSpecificOutput":{"hookEventName":"SessionStart","additionalContext":%s}}\n' \
  "$(printf '%s' "$COMBINED" | python3 -c "import json,sys; print(json.dumps(sys.stdin.read()))")"