#!/bin/bash
# =============================================================================
# update-gitops-status.sh
#
# Purpose:
#   Runs drift-check playbook and generates a JSON status snapshot for
#   gitops-status-server. This replaces Pushgateway metric updates with
#   richer JSON status suitable for Grafana visualization.
#
# Usage:
#   ./update-gitops-status.sh
#
# Environment Variables:
#   GITOPS_STATUS_SERVER_URL - URL of gitops-status-server API
#                              (default: http://gitops-status-server.observability-stack.svc.cluster.local:80)
#   REPO_NAME                - Repository name (default: rsyslog)
#   SERVER_NAME              - Server name (default: rsyslog-lab)
#
# Output:
#   Generates JSON structure:
#   {
#     "repo": "rsyslog",
#     "server": "rsyslog-lab",
#     "sync_status": "SYNCED" or "OUT_OF_SYNC",
#     "drift_count": <number>,
#     "files": [{"name": "rsyslog.conf"}, ...],
#     "last_check": "2026-04-21T10:30:00Z"
#   }
#
# Exit codes:
#   0 - Success (regardless of sync status)
#   1 - Failure (playbook error, network error, etc.)
# =============================================================================

set -e

# Configuration
GITOPS_STATUS_SERVER_URL="${GITOPS_STATUS_SERVER_URL:-http://gitops-status-server.observability-stack.svc.cluster.local:80}"
REPO_NAME="${REPO_NAME:-rsyslog}"
SERVER_NAME="${SERVER_NAME:-rsyslog-lab}"
INVENTORY_FILE="ansible/inventory/hosts.yml"
PLAYBOOK="ansible/playbooks/drift-check.yml"

echo "==> Running drift check playbook..."
echo "    Inventory: $INVENTORY_FILE"
echo "    Playbook:  $PLAYBOOK"

# Run drift-check playbook in JSON output mode and capture results
# We use --diff to get detailed change information
# Exit code: 0 = synced, non-zero = drift or error
set +e
PLAYBOOK_OUTPUT=$(ANSIBLE_STDOUT_CALLBACK=json ansible-playbook \
  -i "$INVENTORY_FILE" \
  "$PLAYBOOK" \
  2>&1)
DRIFT_RC=$?
set -e

# Determine sync status
if [ "$DRIFT_RC" -eq 0 ]; then
  SYNC_STATUS="SYNCED"
  echo "==> Status: SYNCED - server configuration matches Git"
else
  SYNC_STATUS="OUT_OF_SYNC"
  echo "==> Status: OUT_OF_SYNC - drift detected"
fi

# Parse changed files from playbook output
# Look for tasks that reported changed=true
CHANGED_FILES=()
DRIFT_COUNT=0

# Extract file changes from JSON output
# main_config_check tracks rsyslog.conf
# rsyslogd_check tracks rsyslog.d/* files
if echo "$PLAYBOOK_OUTPUT" | grep -q '"main_config_check".*"changed".*true'; then
  CHANGED_FILES+=("rsyslog.conf")
  ((DRIFT_COUNT++))
  echo "    - Drift detected: rsyslog.conf"
fi

# Check if rsyslog.d directory has changes
if echo "$PLAYBOOK_OUTPUT" | grep -q '"rsyslogd_check".*"changed".*true'; then
  # Try to extract specific filenames from diff output
  # Format: files/rsyslog.d/30-lab.conf
  while IFS= read -r line; do
    if [[ "$line" =~ files/rsyslog\.d/([^[:space:]]+\.conf) ]]; then
      filename="${BASH_REMATCH[1]}"
      CHANGED_FILES+=("rsyslog.d/$filename")
      ((DRIFT_COUNT++))
      echo "    - Drift detected: rsyslog.d/$filename"
    fi
  done < <(echo "$PLAYBOOK_OUTPUT" | grep -oP 'files/rsyslog\.d/[^[:space:]]+\.conf' || true)
  
  # If we couldn't extract specific files but know rsyslog.d changed,
  # add a generic entry
  if [ ${#CHANGED_FILES[@]} -eq 0 ] || [ ${#CHANGED_FILES[@]} -eq 1 ]; then
    CHANGED_FILES+=("rsyslog.d/*")
    ((DRIFT_COUNT++))
    echo "    - Drift detected: rsyslog.d/* (multiple files)"
  fi
fi

# Check for missing files on server
if echo "$PLAYBOOK_OUTPUT" | grep -q '"extra_files_on_server".*true'; then
  CHANGED_FILES+=("(missing files on server)")
  ((DRIFT_COUNT++))
  echo "    - Drift detected: files missing on server"
fi

echo "==> Drift count: $DRIFT_COUNT"

# Build JSON file list
FILES_JSON="[]"
if [ ${#CHANGED_FILES[@]} -gt 0 ]; then
  FILES_JSON="["
  for i in "${!CHANGED_FILES[@]}"; do
    if [ $i -gt 0 ]; then
      FILES_JSON+=","
    fi
    FILES_JSON+="{\"name\":\"${CHANGED_FILES[$i]}\"}"
  done
  FILES_JSON+="]"
fi

# Generate ISO timestamp
TIMESTAMP=$(date -u +"%Y-%m-%dT%H:%M:%SZ")

# Build complete JSON status
STATUS_JSON=$(cat <<EOF
{
  "repo": "$REPO_NAME",
  "server": "$SERVER_NAME",
  "sync_status": "$SYNC_STATUS",
  "drift_count": $DRIFT_COUNT,
  "files": $FILES_JSON,
  "last_check": "$TIMESTAMP"
}
EOF
)

echo "==> Generated JSON status:"
echo "$STATUS_JSON" | jq '.' 2>/dev/null || echo "$STATUS_JSON"

# Send JSON to gitops-status-server
# API endpoint: POST /api/status
echo "==> Sending status to gitops-status-server..."
echo "    URL: $GITOPS_STATUS_SERVER_URL/api/status"

HTTP_CODE=$(curl -s -o /dev/null -w "%{http_code}" \
  -X POST \
  -H "Content-Type: application/json" \
  -d "$STATUS_JSON" \
  "$GITOPS_STATUS_SERVER_URL/api/status")

if [ "$HTTP_CODE" -ge 200 ] && [ "$HTTP_CODE" -lt 300 ]; then
  echo "==> Status update successful (HTTP $HTTP_CODE)"
  exit 0
else
  echo "==> ERROR: Status update failed (HTTP $HTTP_CODE)"
  exit 1
fi