#!/bin/bash

# dd0c Watch Loop (replaces the old git pull + docker compose up loop)
# Run this on the NAS: watch -n300 './watch-loop.sh'
# Or as a cron: */5 * * * * cd ~/services/dd0c/products && ./watch-loop.sh >> /tmp/dd0c-watch.log 2>&1

set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
cd "$SCRIPT_DIR"

REGISTRY="${REGISTRY:-reg.dd0c.net}"
LOCK="/tmp/dd0c-watch.lock"

# Prevent concurrent runs
if [ -f "$LOCK" ]; then
  PID=$(cat "$LOCK")
  if kill -0 "$PID" 2>/dev/null; then
    echo "$(date -u '+%H:%M:%S') Already running (pid $PID), skipping"
    exit 0
  fi
fi
echo $$ > "$LOCK"
trap 'rm -f "$LOCK"' EXIT

# Pull latest code
BEFORE=$(git rev-parse HEAD 2>/dev/null || echo "none")
git pull --ff-only 2>/dev/null || { echo "$(date -u '+%H:%M:%S') git pull failed"; exit 1; }
AFTER=$(git rev-parse HEAD 2>/dev/null || echo "none")

if [ "$BEFORE" = "$AFTER" ]; then
  echo "$(date -u '+%H:%M:%S') No changes"
  exit 0
fi

echo "$(date -u '+%H:%M:%S') New commits: $BEFORE → $AFTER"

# Detect which products changed
CHANGED=$(git diff --name-only "$BEFORE" "$AFTER" 2>/dev/null || echo "")

declare -A SERVICES=(
  ["02-iac-drift-detection"]="dd0c-drift:02-iac-drift-detection/saas"
  ["03-alert-intelligence"]="dd0c-alert:03-alert-intelligence"
  ["04-lightweight-idp"]="dd0c-portal:04-lightweight-idp"
  ["05-aws-cost-anomaly"]="dd0c-cost:05-aws-cost-anomaly"
  ["06-runbook-automation"]="dd0c-run:06-runbook-automation/saas"
)

echo "secret" | docker login "$REGISTRY" --username dd0c --password-stdin 2>/dev/null || true
REBUILT=0
for prefix in "${!SERVICES[@]}"; do
  if echo "$CHANGED" | grep -q "products/$prefix/"; then
    IFS=: read -r img ctx <<< "${SERVICES[$prefix]}"
    TAG="${REGISTRY}/${img}:latest"
    echo "$(date -u '+%H:%M:%S') Building $img..."
    if docker build -t "$TAG" --build-arg BUILD_SHA=$(git rev-parse --short HEAD) --build-arg BUILD_TIME=$(date -u +%Y%m%dT%H%M%S) "./$ctx" --no-cache && docker push "$TAG"; then
      echo "$(date -u '+%H:%M:%S') ✓ $img pushed"
      ((REBUILT++)) || true
    else
      echo "$(date -u '+%H:%M:%S') ✗ $img build failed"
    fi
  fi
done

if [ "$REBUILT" -gt 0 ]; then
  echo "$(date -u '+%H:%M:%S') Deploying $REBUILT service(s)..."
  docker compose pull
  docker compose up -d
  echo "$(date -u '+%H:%M:%S') Done"
else
  # Still might need compose changes (new infra services, env vars, etc.)
  if echo "$CHANGED" | grep -q "docker-compose.yml"; then
    echo "$(date -u '+%H:%M:%S') Compose file changed, redeploying..."
    docker compose up -d
  fi
fi