Learn PHP Tutorial - Cody Paste

public function generateCoupon($numCoupons = 32500) {
        // Define allowed characters for alphabet and digits
        $alphabet = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
        $digits = '0123456789';
        $alphaLength = strlen($alphabet);
        $digitLength = strlen($digits);

        // Coupon amount distribution
        $amountDistribution = [
            500 => 2000,  // 2000 coupons with amount 500
            200 => 5000,  // 5000 coupons with amount 200
            100 => 7000,  // 7000 coupons with amount 100
            50  => 18500  // 18500 coupons with amount 50
        ];

        // Prepare the data for batch insert
        $insertData = [];
        $couponCount = 0;
        $coupons = [];

        // Loop through each amount distribution
        foreach ($amountDistribution as $amount => $count) {
            for ($i = 0; $i < $count; $i++) {
                // Generate a unique coupon code in the format AAA111
                $couponCode = '';
                while (true) {
                    // First 3 characters: Alphabetical
                    $couponCode = '';
                    for ($j = 0; $j < 3; $j++) {
                        $couponCode .= $alphabet[rand(0, $alphaLength - 1)];
                    }

                    // Last 3 characters: Numeric
                    for ($k = 0; $k < 3; $k++) {
                        $couponCode .= $digits[rand(0, $digitLength - 1)];
                    }

                    // Check if the coupon code is unique
                    if (!in_array($couponCode, $coupons)) {
                        // Add unique coupon to the list and exit while loop
                        $coupons[] = $couponCode;
                        break;
                    }
                }

                // Prepare data for batch insert
                $insertData[] = [
                    'coupon' => $couponCode,
                    'amount' => $amount,
                    'expire_date' => date('Y-m-d'), // Set expire_date to today's date
                    'status' => 1
                ];

                $couponCount++;

                // Optional: Break early for testing purposes
                if ($couponCount >= $numCoupons) {
                    break 2; // Break out of both loops
                }
            }
        }

        // Insert coupons in batches (chunk size of 500 or smaller to avoid memory issues)
        $chunks = array_chunk($insertData, 500);
        foreach ($chunks as $chunk) {
            $this->db->insert_batch('coupon', $chunk); // Insert the current chunk
        }

        echo count($insertData); // Return the number of coupons inserted
    }