<?php

use App\Models\Notification;
use Illuminate\Support\Facades\DB;
use Carbon\Carbon;

/**
 * Get last notification time for a notification code
 * Returns null if never sent (first time)
 */
function getLastNotificationTime(string $notificationCode): ?Carbon
{
    $lastNotification = Notification::where('notification_code', $notificationCode)
        ->orderBy('created_at', 'DESC')
        ->first();
    
    return $lastNotification ? $lastNotification->created_at : null;
}

/**
 * Check if we should run the check
 * Returns true if last notification was more than 5 minutes ago (or never sent)
 */
function shouldCheckNotification(string $notificationCode, int $minMinutes = 5): bool
{
    $lastNotification = getLastNotificationTime($notificationCode);
    
    // If never sent, should check
    if (!$lastNotification) {
        return true;
    }
    
    // If last notification was more than 5 minutes ago, should check
    return $lastNotification->diffInMinutes(now()) >= $minMinutes;
}

/**
 * Get records created/updated after last notification
 * Returns null if first run (should check all records)
 */
function getLastCheckTimestamp(string $notificationCode): ?Carbon
{
    $lastNotification = getLastNotificationTime($notificationCode);
    
    // If never sent, return null (will check all records on first run)
    if (!$lastNotification) {
        return null;
    }
    
    // Check records after last notification
    return $lastNotification;
}

/**
 * Check if notification already sent for same issue (duplicate prevention)
 * Compares filter_params to detect same issue
 * 
 * @param string $notificationCode
 * @param array|null $filterParams
 * @return bool True if duplicate exists
 */
function isNotificationDuplicate(string $notificationCode, ?array $filterParams = null): bool
{
    // If no filter params, can't check for duplicates
    if (empty($filterParams)) {
        return false;
    }
    
    // Get last notification with same code and filter params
    $lastNotification = Notification::where('notification_code', $notificationCode)
        ->whereNotNull('filter_params')
        ->orderBy('created_at', 'DESC')
        ->first();
    
    if (!$lastNotification || !$lastNotification->filter_params) {
        return false; // No previous notification
    }
    
    // Compare filter_params (normalize arrays for comparison)
    $lastParams = is_array($lastNotification->filter_params) 
        ? $lastNotification->filter_params 
        : json_decode($lastNotification->filter_params, true);
    
    // Check if same table and same conditions
    if (isset($lastParams['table']) && isset($filterParams['table'])) {
        if ($lastParams['table'] !== $filterParams['table']) {
            return false; // Different tables, not duplicate
        }
    }
    
    // Compare conditions (simplified - check if same IDs or same conditions)
    if (isset($lastParams['conditions']) && isset($filterParams['conditions'])) {
        // If both have 'id' conditions, check if they overlap
        if (isset($lastParams['conditions']['id']) && isset($filterParams['conditions']['id'])) {
            $lastIds = is_array($lastParams['conditions']['id']) 
                ? $lastParams['conditions']['id'] 
                : [$lastParams['conditions']['id']];
            $newIds = is_array($filterParams['conditions']['id']) 
                ? $filterParams['conditions']['id'] 
                : [$filterParams['conditions']['id']];
            
            // If all new IDs are already in last notification, it's duplicate
            $newUniqueIds = array_diff($newIds, $lastIds);
            if (empty($newUniqueIds)) {
                return true; // All IDs already notified
            }
        }
        
        // For other conditions, do simple comparison
        // If conditions are exactly same, it's duplicate
        $lastConditions = json_encode($lastParams['conditions'], JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES);
        $newConditions = json_encode($filterParams['conditions'], JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES);
        
        if ($lastConditions === $newConditions) {
            return true; // Exact same conditions
        }
    }
    
    return false; // Not duplicate
}

/**
 * Get already notified IDs from last notification
 * Used to filter out already notified records
 * 
 * @param string $notificationCode
 * @return array Array of already notified IDs
 */
function getAlreadyNotifiedIds(string $notificationCode): array
{
    $lastNotification = Notification::where('notification_code', $notificationCode)
        ->whereNotNull('filter_params')
        ->orderBy('created_at', 'DESC')
        ->first();
    
    if (!$lastNotification || !$lastNotification->filter_params) {
        return []; // No previous notification
    }
    
    $filterParams = is_array($lastNotification->filter_params) 
        ? $lastNotification->filter_params 
        : json_decode($lastNotification->filter_params, true);
    
    if (isset($filterParams['conditions']['id'])) {
        $ids = $filterParams['conditions']['id'];
        return is_array($ids) ? $ids : [$ids];
    }
    
    return [];
}