#!/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 via Infinity DS.
#
# Flow:
#   1. Execute ansible/playbooks/drift-check.yml (check mode, read-only)
#   2. Capture exit code to determine sync status
#   3. Parse playbook output to extract changed files
#   4. Build structured JSON with metadata
#   5. POST JSON to gitops-status-server API
#
# 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)
#
# Generated JSON Structure:
#   {
#     "repo": "rsyslog",
#     "server": "rsyslog-lab",
#     "sync_status": "SYNCED" or "OUT_OF_SYNC",
#     "drift_count": <number>,
#     "files": [{"name": "rsyslog.conf"}, {"name": "rsyslog.d/30-lab.conf"}],
#     "last_check": "2026-04-21T10:30:00Z"
#   }
#
# Exit Codes:
#   0 - Success (JSON posted to gitops-status-server regardless of sync status)
#   1 - Failure (playbook error, network error, JSON post failure, etc.)
#
# =============================================================================

set -euo pipefail

# ─────────────────────────────────────────────────────────────────────────────
# 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 "═══════════════════════════════════════════════════════════════════════════════"
echo "  GitOps Status Update"
echo "  Repository: $REPO_NAME | Server: $SERVER_NAME"
echo "  Target: $GITOPS_STATUS_SERVER_URL"
echo "═══════════════════════════════════════════════════════════════════════════════"
echo ""

# ─────────────────────────────────────────────────────────────────────────────────
# Step 1: Run drift-check playbook
# ─────────────────────────────────────────────────────────────────────────────────
echo "Step 1/4: Running drift-check playbook..."

# Capture playbook output to a temp file for parsing
PLAYBOOK_LOG=$(mktemp)
KEEP_LOG="${KEEP_PLAYBOOK_LOG:-false}"
if [ "$KEEP_LOG" = "true" ]; then
  PLAYBOOK_LOG="./drift-check-output.log"
  echo "  Playbook output will be saved to: $PLAYBOOK_LOG"
else
  trap "rm -f $PLAYBOOK_LOG" EXIT
fi

# Run playbook (no -v flag to avoid file descriptor exhaustion in containers)
# Exit code: 0 = synced, non-zero = drift detected (expected)
# Disable callbacks and reduce file watchers to prevent inotify exhaustion
set +e
ANSIBLE_CALLBACKS_ENABLED="" \
ANSIBLE_STDOUT_CALLBACK=minimal \
ansible-playbook \
  -i "$INVENTORY_FILE" \
  "$PLAYBOOK" \
  > "$PLAYBOOK_LOG" 2>&1
DRIFT_RC=$?
set -e

# Show playbook output for debugging (compact)
echo "Playbook output (last 25 lines):"
cat "$PLAYBOOK_LOG" | tail -25
echo ""
echo "DEBUG: Full playbook output saved to: $PLAYBOOK_LOG"
echo ""

# ─────────────────────────────────────────────────────────────────────────────────
# Step 2: Determine sync status and collect changed files
# ─────────────────────────────────────────────────────────────────────────────────
echo "Step 2/4: Analyzing drift detection results..."

CHANGED_FILES=()
DRIFT_COUNT=0

# Exit code 0 = synced (all tasks succeeded)
# Exit code non-zero = drift detected (fail task was reached)
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 - configuration drift detected"
fi

# Extract structured drifted files from playbook output
# The drift-check.yml playbook outputs: DRIFTED_FILES=file1,file2,file3
# Search for the pattern in the output
echo "  DEBUG: Searching for DRIFTED_FILES in playbook output..."
if grep -q "DRIFTED_FILES=" "$PLAYBOOK_LOG"; then
  echo "  DEBUG: Found DRIFTED_FILES pattern"
  DRIFTED_FILES_STR=$(grep "DRIFTED_FILES=" "$PLAYBOOK_LOG" | tail -1)
  echo "  DEBUG: Raw line: $DRIFTED_FILES_STR"
  
  # Remove ANSI color codes and extract the value
  # Handle both formats: "DRIFTED_FILES=..." and "msg": "DRIFTED_FILES=..."
  DRIFTED_FILES_STR=$(echo "$DRIFTED_FILES_STR" | sed 's/.*DRIFTED_FILES=//' | sed 's/\x1b\[[0-9;]*m//g' | sed 's/".*$//' | xargs)
  echo "  DEBUG: Extracted value: '$DRIFTED_FILES_STR'"
  
  # Check if the value is an empty list ([] or empty string)
  if [ -n "$DRIFTED_FILES_STR" ] && [ "$DRIFTED_FILES_STR" != "[]" ] && [ "$DRIFTED_FILES_STR" != "" ]; then
    # Parse comma-separated list into array
    IFS=',' read -ra CHANGED_FILES <<<"$DRIFTED_FILES_STR"
    
    echo "  DEBUG: Parsed ${#CHANGED_FILES[@]} files"
    
    # Clean up whitespace and normalize paths
    for i in "${!CHANGED_FILES[@]}"; do
      CHANGED_FILES[$i]=$(echo "${CHANGED_FILES[$i]}" | xargs)
      
      # Convert full paths to relative paths for cleaner output
      if [[ "${CHANGED_FILES[$i]}" == /etc/rsyslog.conf ]]; then
        CHANGED_FILES[$i]="rsyslog.conf"
      elif [[ "${CHANGED_FILES[$i]}" == /etc/rsyslog.d/* ]]; then
        CHANGED_FILES[$i]=$(echo "${CHANGED_FILES[$i]}" | sed 's|^/etc/||')
      fi
      
      if [ "$SYNC_STATUS" = "OUT_OF_SYNC" ]; then
        echo "    - Drift detected in: ${CHANGED_FILES[$i]}"
      fi
    done
    
    DRIFT_COUNT=${#CHANGED_FILES[@]}
  else
    echo "  DEBUG: DRIFTED_FILES is empty or []"
  fi
else
  echo "  DEBUG: DRIFTED_FILES not found in playbook output"
  echo "  DEBUG: Attempting to parse from changed task output..."
  
  # Fallback: Look for "changed:" indicators in the playbook output
  if grep -q "changed: \[" "$PLAYBOOK_LOG"; then
    echo "  DEBUG: Found changed tasks, but no structured DRIFTED_FILES output"
    echo "  DEBUG: This might indicate a playbook output format issue"
  fi
fi

# Additional validation: If OUT_OF_SYNC but no files found, show warning
if [ "$SYNC_STATUS" = "OUT_OF_SYNC" ] && [ "$DRIFT_COUNT" -eq 0 ]; then
  echo "  ⚠️  WARNING: Status is OUT_OF_SYNC but no drifted files were extracted"
  echo "  ⚠️  This might indicate a parsing issue. Check the playbook output above."
fi

echo "  Total drift count: $DRIFT_COUNT"
echo ""

# ─────────────────────────────────────────────────────────────────────────────────
# Step 3: Build JSON payload
# ─────────────────────────────────────────────────────────────────────────────────
echo "Step 3/4: Building JSON payload..."

# Convert files array to JSON
FILES_JSON="[]"
if [ ${#CHANGED_FILES[@]} -gt 0 ]; then
  FILES_JSON="["
  for i in "${!CHANGED_FILES[@]}"; do
    if [ "$i" -gt 0 ]; then
      FILES_JSON+=","
    fi
    # Escape special characters in filenames for JSON
    escaped_name="${CHANGED_FILES[$i]//\\/\\\\}"
    escaped_name="${escaped_name//\"/\\\"}"
    FILES_JSON+="{\"name\":\"$escaped_name\"}"
  done
  FILES_JSON+="]"
fi

# Generate ISO 8601 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:"
echo "$STATUS_JSON" | jq '.' 2>/dev/null || echo "$STATUS_JSON"
echo ""

# ─────────────────────────────────────────────────────────────────────────────────
# Step 4: Send JSON to gitops-status-server
# ─────────────────────────────────────────────────────────────────────────────────
echo "Step 4/4: Sending status to gitops-status-server..."
echo "  URL: $GITOPS_STATUS_SERVER_URL/api/status"
echo "  Method: POST"
echo ""

# Create temporary files for response
RESPONSE_BODY=$(mktemp)
trap "rm -f $RESPONSE_BODY" EXIT

# POST the JSON to the gitops-status-server API with full error reporting
# Capture both response code and body for debugging
HTTP_CODE=$(curl -s -w "%{http_code}" \
  -X POST \
  -H "Content-Type: application/json" \
  -d "$STATUS_JSON" \
  "$GITOPS_STATUS_SERVER_URL/api/status" \
  -o "$RESPONSE_BODY" 2>&1 || true)

# Extract HTTP code (last 3 digits)
HTTP_CODE="${HTTP_CODE: -3}"

echo "  Response: HTTP $HTTP_CODE"

# Show response body for debugging (especially on error)
if [ -s "$RESPONSE_BODY" ]; then
  echo "  Response Body:"
  sed 's/^/    /' "$RESPONSE_BODY"
fi
echo ""

if [ "$HTTP_CODE" -ge 200 ] && [ "$HTTP_CODE" -lt 300 ]; then
  echo "═══════════════════════════════════════════════════════════════════════════════"
  echo "  ✓ Status update successful (HTTP $HTTP_CODE)"
  echo "  JSON has been sent to gitops-status-server"
  echo ""
  
  # Verify the JSON was actually received and stored
  echo "  Verifying JSON storage on gitops-status-server..."
  sleep 1  # Brief delay to ensure server processed the POST
  
  VERIFY_JSON=$(curl -s "$GITOPS_STATUS_SERVER_URL/status.json" 2>&1 || true)
  if echo "$VERIFY_JSON" | grep -q "\"repo\".*\"$REPO_NAME\""; then
    echo "  ✓ Verified: Latest JSON stored correctly on server"
    echo ""
    echo "  Grafana Infinity datasource will now read the updated JSON from:"
    echo "  $GITOPS_STATUS_SERVER_URL/status.json"
  else
    echo "  ⚠ Warning: Could not verify JSON storage"
    echo "  Response from /status.json:"
    echo "  $VERIFY_JSON" | sed 's/^/    /'
  fi
  
  echo "═══════════════════════════════════════════════════════════════════════════════"
  exit 0
else
  echo "═══════════════════════════════════════════════════════════════════════════════"
  echo "  ✗ ERROR: Status update failed with HTTP $HTTP_CODE"
  echo "  Debugging Information:"
  echo "  - Server URL: $GITOPS_STATUS_SERVER_URL"
  echo "  - Endpoint: /api/status"
  echo "  - Check gitops-status-server connectivity (ping/nslookup)"
  echo "  - Verify service port and internal port mapping"
  echo "  - Ensure /api/status endpoint accepts POST requests"
  echo "═══════════════════════════════════════════════════════════════════════════════"
  exit 1
fi