(function () {
        'use strict';

        const SELECTORS = {
            inquiryBtn: '#inquiry_btn',
            companyInput: 'input[name="company"]',
        };
        const UNDETERMINED_VALUE = '未定';
        const WARNING_MESSAGE =
            '「法人名・屋号」が「未定」と入力されています。ご請求の資料は「創業手帳(起業後のユーザー向け)」でよろしいでしょうか。';

        document.addEventListener('DOMContentLoaded', function () {
            const inquiryBtn = document.querySelector(SELECTORS.inquiryBtn);
            if (!inquiryBtn) return;

            const btnWrapper = inquiryBtn.closest('div');
            if (!btnWrapper || !btnWrapper.parentNode) return;

            const companyInput = document.querySelector(SELECTORS.companyInput);
            if (!companyInput) return;

            const warning = document.createElement('p');
            warning.id = 'company_name_warning';
            warning.className = 'c_formAlert_Mitei';
            warning.setAttribute('role', 'alert');
            warning.style.display = 'none';
            warning.textContent = WARNING_MESSAGE;
            btnWrapper.parentNode.insertBefore(warning, btnWrapper);

            const update = function () {
                const isUndetermined = companyInput.value.trim() === UNDETERMINED_VALUE;
                warning.style.display = isUndetermined ? 'block' : 'none';
            };

            companyInput.addEventListener('input', update);
            companyInput.addEventListener('blur', update);

            // 初期表示チェック (自動入力/戻る操作対策)
            update();
        });
    })();