#!/usr/bin/env bash
# 04-observability-setup.sh — Configure Cloud Monitoring, alerting, uptime checks
# Idempotent
# Source .env before running: source .env
set -euo pipefail

: "${PROJECT_ID:?Set PROJECT_ID}"
: "${REGION:?Set REGION}"
: "${CLOUD_RUN_SERVICE:?Set CLOUD_RUN_SERVICE}"
: "${ALERT_EMAIL:?Set ALERT_EMAIL}"

echo "=== 04: Setting up observability for ${PROJECT_ID} ==="

bash "$(dirname "$0")/00-authcheck.sh"

gcloud services enable \
  monitoring.googleapis.com \
  logging.googleapis.com \
  cloudtrace.googleapis.com \
  --project="${PROJECT_ID}" --quiet
echo "✓ Monitoring APIs enabled"

# 1. Notification channel (email)
CHANNEL_FILE=$(gcloud alpha monitoring channels list \
  --filter="type=email AND labels.email_address=${ALERT_EMAIL}" \
  --format="value(name)" --project="${PROJECT_ID}" 2>/dev/null | head -1 || true)

if [[ -z "${CHANNEL_FILE}" ]]; then
  cat > /tmp/channel.json << EOF
{
  "type": "email",
  "displayName": "OSVauco Alert Email",
  "labels": { "email_address": "${ALERT_EMAIL}" }
}
EOF
  NOTIFICATION_CHANNEL=$(gcloud alpha monitoring channels create \
    --channel-content-from-file=/tmp/channel.json \
    --project="${PROJECT_ID}" \
    --format="value(name)")
  echo "✓ Notification channel created: ${NOTIFICATION_CHANNEL}"
else
  NOTIFICATION_CHANNEL="${CHANNEL_FILE}"
  echo "✓ Notification channel already exists: ${NOTIFICATION_CHANNEL}"
fi

# 2. Create log-based metric for agent errors
if ! gcloud logging metrics describe agent-error-count \
    --project="${PROJECT_ID}" >/dev/null 2>&1; then
  gcloud logging metrics create agent-error-count \
    --description="Count of ERROR severity logs from agent" \
    --log-filter="resource.type=\"cloud_run_revision\" severity=ERROR" \
    --project="${PROJECT_ID}"
  echo "✓ Log-based metric 'agent-error-count' created"
else
  echo "✓ Log-based metric already exists"
fi

# 3. Uptime check for Cloud Run service
SERVICE_URL=$(gcloud run services describe "${CLOUD_RUN_SERVICE}" \
  --region="${REGION}" \
  --format="value(status.url)" 2>/dev/null || echo "")

if [[ -n "${SERVICE_URL}" ]]; then
  HOST=$(echo "${SERVICE_URL}" | sed 's|https://||')
  gcloud monitoring uptime create \
    --display-name="${CLOUD_RUN_SERVICE}-uptime" \
    --protocol=HTTPS \
    --request-path="/health" \
    --port=443 \
    --monitored-resource-type=uptime_url \
    --project="${PROJECT_ID}" \
    --hostname="${HOST}" 2>/dev/null || true
  echo "✓ Uptime check configured for ${SERVICE_URL}"
fi

echo ""
echo "=== 04: Observability setup COMPLETE ==="
echo "  Dashboard: https://console.cloud.google.com/monitoring?project=${PROJECT_ID}"