#!/bin/bash
set -euo pipefail

# Perform health check and rollback if necessary
# Usage: ./health-check-and-rollback.sh REPO_PROJECT_PATH IS_PROD HEALTH_CHECK_URL [MAX_ATTEMPTS]

if [ $# -lt 3 ]; then
    echo "Error: Invalid number of arguments"
    echo "Usage: $0 REPO_PROJECT_PATH IS_PROD HEALTH_CHECK_URL [MAX_ATTEMPTS]"
    exit 1
fi

REPO_PROJECT_PATH="$1"
IS_PROD="$2"
HEALTH_CHECK_URL="$3"
MAX_ATTEMPTS="${4:-30}"

CURRENT_LINK_PATH="${REPO_PROJECT_PATH}/current"
RELEASES_PATH="${REPO_PROJECT_PATH}/releases"

echo "🏥 Performing health check..."
echo "Health check URL: $HEALTH_CHECK_URL"

get_current_version() {
    if [ -L "$CURRENT_LINK_PATH" ]; then
        basename "$(readlink -f "$CURRENT_LINK_PATH")"
    else
        echo "unknown"
    fi
}

ATTEMPT=0
while [ "$ATTEMPT" -lt "$MAX_ATTEMPTS" ]; do
  # Check if the service is responding with 200 OK
  HTTP_CODE=$(curl -s -o /dev/null -w '%{http_code}' -m 10 "$HEALTH_CHECK_URL" || echo '000')
  
  if [ "$HTTP_CODE" = "200" ]; then
    echo "✅ Health check passed! (HTTP $HTTP_CODE)"
    CURRENT_VERSION=$(get_current_version)
    echo "📌 Current version: ${CURRENT_VERSION}"
    exit 0
  fi
  
  ATTEMPT=$((ATTEMPT + 1))
  if [ "$ATTEMPT" -eq "$MAX_ATTEMPTS" ]; then
    echo "❌ Health check failed after $MAX_ATTEMPTS attempts (Last HTTP code: $HTTP_CODE)"
    echo "🔄 Rolling back deployment..."
    
    FAILED_VERSION=$(get_current_version)
    echo "❌ Failed version: ${FAILED_VERSION}"
    
    # Check if we have a previous version to roll back to
    if [ -f "${CURRENT_LINK_PATH}/.previous_version" ]; then
        PREVIOUS_VERSION_PATH=$(cat "${CURRENT_LINK_PATH}/.previous_version")
        PREVIOUS_VERSION=$(basename "$PREVIOUS_VERSION_PATH")
        
        if [ -d "$PREVIOUS_VERSION_PATH" ]; then
            echo "🔄 Rolling back to version: ${PREVIOUS_VERSION}"
            
            # Stop failed deployment containers
            cd "$CURRENT_LINK_PATH"
            echo "Stopping failed deployment containers..."
            docker compose -f docker-compose_web.yml down || true
            if [ "$IS_PROD" = "false" ]; then
              docker compose -f docker-compose_staging.yml down || true
            fi
            docker compose -f docker-compose_core.yml down || true
            
            # Switch symlink back to previous version
            ln -sfn "$PREVIOUS_VERSION_PATH" "$CURRENT_LINK_PATH"
            
            # Start previous version containers
            cd "$CURRENT_LINK_PATH"
            docker compose -f docker-compose_core.yml up -d --no-build
            if [ "$IS_PROD" = "true" ]; then
              docker compose -f docker-compose_web.yml up -d --no-build
            else
              docker compose -f docker-compose_web.yml -f docker-compose_staging.yml up -d --no-build
            fi
            
            echo "✅ Rollback completed to version: ${PREVIOUS_VERSION}"
            
            # Mark failed version
            if [ -d "${RELEASES_PATH}/${FAILED_VERSION}" ]; then
                touch "${RELEASES_PATH}/${FAILED_VERSION}/.failed"
                echo "$(date): Health check failed, rolled back to ${PREVIOUS_VERSION}" > "${RELEASES_PATH}/${FAILED_VERSION}/.failure_reason"
            fi
        else
            echo "❌ Previous version directory not found: $PREVIOUS_VERSION_PATH"
            exit 1
        fi
    else
        echo "❌ No previous version information found. Cannot rollback!"
        echo "💡 This might be the first deployment or the previous version info is missing."
        exit 1
    fi
    exit 1
  fi
  
  echo "⏳ Waiting for service to be healthy... (attempt $ATTEMPT/$MAX_ATTEMPTS, HTTP code: $HTTP_CODE)"
  sleep 10
done