ebayShop/app/Http/Requests/CouponRequest.php

<?php

namespace App\Http\Requests;

use Illuminate\Foundation\Http\FormRequest;
use Illuminate\Validation\Rule;

class CouponRequest extends FormRequest
{
    /**
     * Determine if the user is authorized to make this request.
     *
     * @return bool
     */
    public function authorize()
    {
        return true;
    }

    /**
     * Get the validation rules that apply to the request.
     *
     * @return array
     */
    public function rules()
    {
        $productsRule           = 'sometimes';
        $minBuyRule             = 'sometimes';
        $maxDiscountRule        = 'sometimes';
        if ($this->request->get('type') == 'product_base') {
            $productsRule       = 'required';
        }
        if ($this->request->get('type') == 'cart_base') {
            $minBuyRule         = ['required','numeric','min:1'];
            $maxDiscountRule    = ['required','numeric','min:1'];
        }
        return [
            'type'          => ['required'],
            'code'          => ['required', Rule::unique('coupons')->ignore($this->coupon), 'max:255',],
            'discount'      => ['required','numeric','min:1'],
            'discount_type' => ['required'],
            'product_ids'   => $productsRule,
            'min_buy'       => $minBuyRule,
            'max_discount'  => $maxDiscountRule,
            'date_range'    => ['required'],
            'start_date'    => ['required'],
            'end_date'      => ['required'],
            'details'       => ['required'],
        ];
    }

    /**
     * Get the error messages for the defined validation rules.
     *
     * @return array
     */
    public function messages()
    {
        return [
            'type.required'         => translate('Coupon type is required'),
            'code.required'         => translate('Coupon code is required'),
            'code.unique'           => translate('Coupon already exist for this coupon code'),
            'code.max'              => translate('Max 255 characters'),
            'product_ids.required'  => translate('Product is required'),
            'discount.required'     => translate('Discount is required'),
            'discount.numeric'      => translate('Discount should be numeric type'),
            'discount.min'          => translate('Discount should be l or greater'),
            'discount_type.required'=> translate('Discount type is required'),
            'min_buy.required'      => translate('Minimum shopping amount is required'),
            'min_buy.numeric'       => translate('Minimum shopping amount should be numeric type'),
            'min_buy.min'           => translate('Minimum shopping amount should be l or greater'),
            'max_discount.required' => translate('Max discount amount is required'),
            'max_discount.numeric'  => translate('Max discount amount should be numeric type'),
            'max_discount.min'      => translate('Max discount amount should be l or greater'),
            'date_range.required'   => translate('Date Range is required'),
        ];
    }


    protected function prepareForValidation()
    {
        $date_range = explode(" - ", $this->date_range);
        $coupon_details = null;
        if ($this->type == "product_base") {
            $coupon_details = array();
            foreach($this->product_ids as $product_id) {
                $data['product_id'] = $product_id;
                array_push($coupon_details, $data);
            }
            $coupon_details = json_encode($coupon_details);
        }
        elseif ($this->type == "cart_base") {
            $data                     = array();
            $data['min_buy']          = $this->min_buy;
            $data['max_discount']     = $this->max_discount;
            $coupon_details           = json_encode($data);
        }

        $this->merge([
            'start_date'    => strtotime($date_range[0]),
            'end_date'      => strtotime($date_range[1]),
            'details'       => $coupon_details
        ]);
    }
}