<?php
require_once __DIR__ . '/../app/lib/auth.php';
require_once __DIR__ . '/../app/lib/db.php';
require_once __DIR__ . '/../app/lib/helpers.php';
require_once __DIR__ . '/../app/lib/transaction_service.php';
require_once __DIR__ . '/../app/lib/transaction_form_service.php';

check_auth();

$pdo = db();
$uid = user_id();
$error = '';
$success = '';

$stmt = $pdo->prepare("
    SELECT *
    FROM accounts
    WHERE user_id = ?
      AND is_active = 1
    ORDER BY
        FIELD(account_type, 'bank', 'card', 'cash', 'other'),
        id ASC
");
$stmt->execute([$uid]);
$accounts = $stmt->fetchAll();

$stmt = $pdo->prepare("
    SELECT *
    FROM categories
    WHERE user_id = ?
      AND is_active = 1
    ORDER BY category_type, sort_order, id
");
$stmt->execute([$uid]);
$categories = $stmt->fetchAll();

$defaults = get_transaction_form_defaults($uid);
$lastForm = $_SESSION['tx_create_last_form'] ?? [];

$form = [
    'transaction_type' => 'expense',
    'account_id' => (int)($defaults['default_account_id'] ?? 0),
    'related_account_id' => 0,
    'category_id' => (int)($defaults['default_expense_category_id'] ?? 0),
    'amount' => '',
    'transaction_date' => date('Y-m-d'),
    'merchant_name' => '',
    'description' => '',
    'is_installment' => 0,
    'installment_months' => '',
    'installment_interest_rate' => '0',
    'installment_interest_total' => '',
    'installment_total_billed' => '',
    'continue_after_save' => !empty($defaults['continue_after_save']) ? 1 : 0,
    'keep_last_values' => !empty($defaults['keep_last_values']) ? 1 : 0,
    'save_as_defaults' => 0,
];

if (!empty($defaults['keep_last_values']) && !empty($lastForm)) {
    $form = array_merge($form, $lastForm);
}

$copyId = (int)($_GET['copy_id'] ?? 0);

if ($copyId > 0 && $_SERVER['REQUEST_METHOD'] !== 'POST') {
    $stmt = $pdo->prepare("
        SELECT *
        FROM transactions
        WHERE id = ?
          AND user_id = ?
        LIMIT 1
    ");
    $stmt->execute([$copyId, $uid]);
    $copy = $stmt->fetch();

    if ($copy) {
        $form = array_merge($form, [
            'transaction_type' => $copy['transaction_type'],
            'account_id' => (int)$copy['account_id'],
            'related_account_id' => (int)($copy['related_account_id'] ?? 0),
            'category_id' => (int)$copy['category_id'],
            'amount' => number_format((float)$copy['amount'], 0),
            'transaction_date' => date('Y-m-d'),
            'merchant_name' => (string)($copy['merchant_name'] ?? ''),
            'description' => (string)($copy['description'] ?? ''),
            'is_installment' => (int)($copy['is_installment'] ?? 0),
            'installment_months' => $copy['installment_months'] ?? '',
            'installment_interest_rate' => (string)($copy['installment_interest_rate'] ?? '0'),
            'installment_interest_total' => !empty($copy['installment_interest_total']) ? number_format((float)$copy['installment_interest_total'], 0) : '',
            'installment_total_billed' => !empty($copy['installment_total_billed']) ? number_format((float)$copy['installment_total_billed'], 0) : '',
            'continue_after_save' => 0,
            'keep_last_values' => 0,
            'save_as_defaults' => 0,
        ]);

        $success = '기존 거래를 복사했습니다. 날짜/메모 수정 후 저장하세요.';
    }
}

if ($_SERVER['REQUEST_METHOD'] === 'POST') {
    try {
        $form = [
            'transaction_type' => $_POST['transaction_type'] ?? 'expense',
            'account_id' => (int)($_POST['account_id'] ?? 0),
            'related_account_id' => !empty($_POST['related_account_id']) ? (int)$_POST['related_account_id'] : 0,
            'category_id' => (int)($_POST['category_id'] ?? 0),
            'amount' => trim((string)($_POST['amount'] ?? '')),
            'transaction_date' => $_POST['transaction_date'] ?? date('Y-m-d'),
            'merchant_name' => trim((string)($_POST['merchant_name'] ?? '')),
            'description' => trim((string)($_POST['description'] ?? '')),
            'is_installment' => (int)($_POST['is_installment'] ?? 0),
            'installment_months' => trim((string)($_POST['installment_months'] ?? '')),
            'installment_interest_rate' => trim((string)($_POST['installment_interest_rate'] ?? '0')),
            'installment_interest_total' => trim((string)($_POST['installment_interest_total'] ?? '')),
            'installment_total_billed' => trim((string)($_POST['installment_total_billed'] ?? '')),
            'continue_after_save' => !empty($_POST['continue_after_save']) ? 1 : 0,
            'keep_last_values' => !empty($_POST['keep_last_values']) ? 1 : 0,
            'save_as_defaults' => !empty($_POST['save_as_defaults']) ? 1 : 0,
        ];

        $transactionType = $form['transaction_type'];
        $accountId = (int)$form['account_id'];
        $categoryId = (int)$form['category_id'];
        $amount = (float)str_replace(',', '', $form['amount']);
        $transactionDate = $form['transaction_date'];
        $merchantName = $form['merchant_name'];
        $description = $form['description'];
        $relatedAccountId = $form['related_account_id'] > 0 ? (int)$form['related_account_id'] : null;

        $isInstallment = (int)$form['is_installment'];
        $installmentMonths = $form['installment_months'] !== '' ? (int)$form['installment_months'] : null;
        $installmentInterestRate = $form['installment_interest_rate'] !== '' ? (float)$form['installment_interest_rate'] : 0.0;
        $installmentInterestTotal = $form['installment_interest_total'] !== ''
            ? (float)str_replace(',', '', $form['installment_interest_total'])
            : null;
        $installmentTotalBilled = $form['installment_total_billed'] !== ''
            ? (float)str_replace(',', '', $form['installment_total_billed'])
            : null;

        if ($amount <= 0) {
            throw new RuntimeException('금액은 0보다 커야 합니다.');
        }

        if (!in_array($transactionType, ['income', 'expense', 'transfer', 'card_payment'], true)) {
            throw new RuntimeException('거래 유형이 올바르지 않습니다.');
        }

        if ($accountId <= 0) {
            throw new RuntimeException('주 계좌/카드를 선택하세요.');
        }

        if ($categoryId <= 0) {
            throw new RuntimeException('카테고리를 선택하세요.');
        }

        if (in_array($transactionType, ['transfer', 'card_payment'], true) && !$relatedAccountId) {
            throw new RuntimeException('관련 계좌를 선택해야 합니다.');
        }

        if ($relatedAccountId && $relatedAccountId === $accountId) {
            throw new RuntimeException('주 계좌와 관련 계좌는 같을 수 없습니다.');
        }

        if ($transactionType !== 'expense') {
            $isInstallment = 0;
            $installmentMonths = null;
            $installmentInterestRate = 0.0;
            $installmentInterestTotal = null;
            $installmentTotalBilled = null;
        }

        create_transaction([
            'user_id' => $uid,
            'account_id' => $accountId,
            'category_id' => $categoryId,
            'transaction_type' => $transactionType,
            'amount' => $amount,
            'transaction_date' => $transactionDate,
            'merchant_name' => $merchantName !== '' ? $merchantName : null,
            'description' => $description !== '' ? $description : null,
            'related_account_id' => $relatedAccountId,
            'is_installment' => $isInstallment,
            'installment_months' => $installmentMonths,
            'installment_interest_rate' => $installmentInterestRate,
            'installment_interest_total' => $installmentInterestTotal,
            'installment_total_billed' => $installmentTotalBilled,
        ]);

        if ($form['save_as_defaults']) {
            $save = [
                'default_account_id' => 0,
                'default_card_account_id' => 0,
                'default_income_category_id' => 0,
                'default_expense_category_id' => 0,
                'default_transfer_category_id' => 0,
                'default_card_payment_category_id' => 0,
                'keep_last_values' => $form['keep_last_values'],
                'continue_after_save' => $form['continue_after_save'],
            ];

            if ($transactionType === 'income') {
                $save['default_account_id'] = $accountId;
                $save['default_income_category_id'] = $categoryId;
            } elseif ($transactionType === 'expense') {
                $save['default_account_id'] = $accountId;
                $save['default_expense_category_id'] = $categoryId;
            } elseif ($transactionType === 'transfer') {
                $save['default_account_id'] = $accountId;
                $save['default_transfer_category_id'] = $categoryId;
            } elseif ($transactionType === 'card_payment') {
                $save['default_account_id'] = $accountId;
                $save['default_card_payment_category_id'] = $categoryId;
            }

            foreach ($accounts as $acc) {
                if ((int)$acc['id'] === $accountId && $acc['account_type'] === 'card') {
                    $save['default_card_account_id'] = $accountId;
                    break;
                }
            }

            save_transaction_form_defaults($uid, array_merge($defaults, $save));
        }

        if ($form['keep_last_values']) {
            $_SESSION['tx_create_last_form'] = [
                'transaction_type' => $transactionType,
                'account_id' => $accountId,
                'related_account_id' => $relatedAccountId ?: 0,
                'category_id' => $categoryId,
                'amount' => '',
                'transaction_date' => date('Y-m-d'),
                'merchant_name' => $merchantName,
                'description' => '',
                'is_installment' => $isInstallment,
                'installment_months' => $installmentMonths ?? '',
                'installment_interest_rate' => (string)$installmentInterestRate,
                'installment_interest_total' => '',
                'installment_total_billed' => '',
                'continue_after_save' => $form['continue_after_save'],
                'keep_last_values' => $form['keep_last_values'],
                'save_as_defaults' => 0,
            ];
        } else {
            unset($_SESSION['tx_create_last_form']);
        }

        if ($form['continue_after_save']) {
            $success = '저장되었습니다. 계속 등록할 수 있습니다.';
            $form['amount'] = '';
            $form['description'] = '';
            $form['transaction_date'] = date('Y-m-d');
            $form['installment_interest_total'] = '';
            $form['installment_total_billed'] = '';
        } else {
            redirect('/transactions.php');
        }
    } catch (Throwable $e) {
        $error = $e->getMessage();
    }
}

$accountsJson = [];
foreach ($accounts as $acc) {
    $accountsJson[] = [
        'id' => (int)$acc['id'],
        'name' => $acc['account_name'],
        'type' => $acc['account_type'],
        'card_kind' => $acc['card_kind'] ?? null,
        'billing_day' => $acc['billing_day'] ?? null,
        'payment_day' => $acc['payment_day'] ?? null,
        'use_credit_grace_period' => !empty($acc['use_credit_grace_period']) ? 1 : 0,
    ];
}

$categoriesJson = [];
foreach ($categories as $cat) {
    $categoriesJson[] = [
        'id' => (int)$cat['id'],
        'type' => $cat['category_type'],
        'name' => $cat['name'],
    ];
}

require __DIR__ . '/../app/views/header.php';
?>

<div class="page-head">
    <h2>거래 등록</h2>
    <a href="/transactions.php" class="btn btn-outline-secondary">목록</a>
</div>

<?php if ($error): ?>
<div class="alert alert-danger"><?= h($error) ?></div>
<?php endif; ?>

<?php if ($success): ?>
<div class="alert alert-success"><?= h($success) ?></div>
<?php endif; ?>

<div class="card finance-card">
    <div class="card-body">
        <form method="post" class="row g-3" id="transactionForm" autocomplete="off">
            <div class="col-12 col-md-3">
                <label class="form-label">거래 유형</label>
                <select name="transaction_type" id="transaction_type" class="form-select" required>
                    <option value="expense" <?= $form['transaction_type'] === 'expense' ? 'selected' : '' ?>>지출</option>
                    <option value="income" <?= $form['transaction_type'] === 'income' ? 'selected' : '' ?>>수입</option>
                    <option value="transfer" <?= $form['transaction_type'] === 'transfer' ? 'selected' : '' ?>>계좌이체</option>
                    <option value="card_payment" <?= $form['transaction_type'] === 'card_payment' ? 'selected' : '' ?>>카드대금납부</option>
                </select>
            </div>

            <div class="col-12 col-md-3">
                <label class="form-label">주 계좌/카드</label>
                <select name="account_id" id="account_id" class="form-select" required>
                    <option value="0">선택하세요</option>
                    <?php foreach ($accounts as $a): ?>
                        <option
                            value="<?= $a['id'] ?>"
                            data-account-type="<?= h($a['account_type']) ?>"
                            <?= (int)$form['account_id'] === (int)$a['id'] ? 'selected' : '' ?>
                        >
                            <?= h($a['account_name']) ?> (<?= h($a['account_type']) ?>)
                        </option>
                    <?php endforeach; ?>
                </select>
                <div class="form-text" id="account_help_text"></div>
            </div>

            <div class="col-12 col-md-3">
                <label class="form-label">관련 계좌</label>
                <select name="related_account_id" id="related_account_id" class="form-select">
                    <option value="">선택안함</option>
                    <?php foreach ($accounts as $a): ?>
                        <option
                            value="<?= $a['id'] ?>"
                            data-account-type="<?= h($a['account_type']) ?>"
                            <?= (int)$form['related_account_id'] === (int)$a['id'] ? 'selected' : '' ?>
                        >
                            <?= h($a['account_name']) ?> (<?= h($a['account_type']) ?>)
                        </option>
                    <?php endforeach; ?>
                </select>
                <div class="form-text" id="related_account_help">계좌이체/카드대금납부 시 선택</div>
            </div>

            <div class="col-12 col-md-3">
                <label class="form-label">카테고리</label>
                <select name="category_id" id="category_id" class="form-select" required>
                    <option value="0">선택하세요</option>
                    <?php foreach ($categories as $c): ?>
                        <option
                            value="<?= $c['id'] ?>"
                            data-type="<?= h($c['category_type']) ?>"
                            <?= (int)$form['category_id'] === (int)$c['id'] ? 'selected' : '' ?>
                        >
                            [<?= h($c['category_type']) ?>] <?= h($c['name']) ?>
                        </option>
                    <?php endforeach; ?>
                </select>
            </div>

            <div class="col-12 col-md-3">
                <label class="form-label">금액</label>
                <input
                    type="text"
                    name="amount"
                    id="amount"
                    class="form-control"
                    value="<?= h($form['amount']) ?>"
                    inputmode="numeric"
                    required
                >
                <div class="mt-2 d-flex flex-wrap gap-2">
                    <button type="button" class="btn btn-sm btn-outline-secondary quick-amt" data-add="10000">+1만</button>
                    <button type="button" class="btn btn-sm btn-outline-secondary quick-amt" data-add="50000">+5만</button>
                    <button type="button" class="btn btn-sm btn-outline-secondary quick-amt" data-add="100000">+10만</button>
                    <button type="button" class="btn btn-sm btn-outline-secondary" id="amount_clear_btn">초기화</button>
                </div>
            </div>

            <div class="col-12 col-md-3">
                <label class="form-label">거래일</label>
                <input type="date" name="transaction_date" class="form-control" value="<?= h($form['transaction_date']) ?>" required>
            </div>

            <div class="col-12 col-md-3">
                <label class="form-label">결제 방식</label>
                <select name="is_installment" id="is_installment" class="form-select">
                    <option value="0" <?= (int)$form['is_installment'] === 0 ? 'selected' : '' ?>>일시불</option>
                    <option value="1" <?= (int)$form['is_installment'] === 1 ? 'selected' : '' ?>>할부</option>
                </select>
            </div>

            <div class="col-12 col-md-3" id="installment_months_wrap" style="display:none;">
                <label class="form-label">할부 개월</label>
                <select name="installment_months" id="installment_months" class="form-select">
                    <option value="">선택하세요</option>
                    <?php foreach ([2,3,4,5,6,10,12,18,24] as $m): ?>
                        <option value="<?= $m ?>" <?= (string)$form['installment_months'] === (string)$m ? 'selected' : '' ?>>
                            <?= intvalf($m) ?>개월
                        </option>
                    <?php endforeach; ?>
                </select>
            </div>

            <div class="col-12 col-md-3" id="installment_rate_wrap" style="display:none;">
                <label class="form-label">연이자율(%)</label>
                <input
                    type="number"
                    name="installment_interest_rate"
                    id="installment_interest_rate"
                    class="form-control"
                    step="0.01"
                    min="0"
                    value="<?= h($form['installment_interest_rate']) ?>"
                >
            </div>

            <div class="col-12 col-md-3" id="installment_interest_wrap" style="display:none;">
                <label class="form-label">총 할부이자</label>
                <input
                    type="text"
                    name="installment_interest_total"
                    id="installment_interest_total"
                    class="form-control"
                    inputmode="numeric"
                    value="<?= h($form['installment_interest_total']) ?>"
                >
                <div class="form-text">비우면 연이자율로 자동 계산</div>
            </div>

            <div class="col-12 col-md-3" id="installment_total_wrap" style="display:none;">
                <label class="form-label">총 청구금액</label>
                <input
                    type="text"
                    name="installment_total_billed"
                    id="installment_total_billed"
                    class="form-control"
                    inputmode="numeric"
                    value="<?= h($form['installment_total_billed']) ?>"
                >
                <div class="form-text">비우면 원금+이자로 자동 계산</div>
            </div>

            <div class="col-12 col-md-6">
                <label class="form-label">사용처 / 거래처</label>
                <input
                    type="text"
                    name="merchant_name"
                    id="merchant_name"
                    class="form-control"
                    placeholder="예: 스타벅스, 쿠팡, 급여"
                    autocomplete="off"
                    value="<?= h($form['merchant_name']) ?>"
                >
                <div class="form-text">상호명 입력 시 카테고리를 자동 추천합니다.</div>
            </div>

            <div class="col-12 col-md-6">
                <label class="form-label">메모</label>
                <input
                    type="text"
                    name="description"
                    class="form-control"
                    placeholder="간단한 설명"
                    value="<?= h($form['description']) ?>"
                >
            </div>

            <div class="col-12">
                <div id="category_suggest_box" class="alert alert-info py-2 px-3 d-none mb-0"></div>
            </div>

            <div class="col-12">
                <div class="loan-create-highlight">
                    <div class="title">등록 편의 설정</div>
                    <div class="desc">자주 쓰는 카드/계좌와 입력값을 계속 재사용할 수 있습니다.</div>

                    <div class="row g-3 mt-1">
                        <div class="col-12 col-md-4">
                            <div class="form-check">
                                <input class="form-check-input" type="checkbox" name="continue_after_save" id="continue_after_save" value="1" <?= !empty($form['continue_after_save']) ? 'checked' : '' ?>>
                                <label class="form-check-label" for="continue_after_save">저장 후 계속 등록</label>
                            </div>
                        </div>

                        <div class="col-12 col-md-4">
                            <div class="form-check">
                                <input class="form-check-input" type="checkbox" name="keep_last_values" id="keep_last_values" value="1" <?= !empty($form['keep_last_values']) ? 'checked' : '' ?>>
                                <label class="form-check-label" for="keep_last_values">마지막 입력값 유지</label>
                            </div>
                        </div>

                        <div class="col-12 col-md-4">
                            <div class="form-check">
                                <input class="form-check-input" type="checkbox" name="save_as_defaults" id="save_as_defaults" value="1">
                                <label class="form-check-label" for="save_as_defaults">현재 선택을 기본값으로 저장</label>
                            </div>
                        </div>
                    </div>
                </div>
            </div>

            <div class="col-12 d-flex flex-wrap gap-2">
                <button class="btn btn-primary">저장</button>
                <button type="submit" name="continue_after_save" value="1" class="btn btn-outline-primary">저장 후 계속 등록</button>
                <a href="/transactions.php" class="btn btn-outline-secondary">목록</a>
            </div>
        </form>
    </div>
</div>

<script>
(function () {
    const ACCOUNTS = <?= json_encode($accountsJson, JSON_UNESCAPED_UNICODE) ?>;
    const CATEGORIES = <?= json_encode($categoriesJson, JSON_UNESCAPED_UNICODE) ?>;

    const transactionTypeEl = document.getElementById('transaction_type');
    const accountEl = document.getElementById('account_id');
    const accountHelpTextEl = document.getElementById('account_help_text');
    const relatedAccountEl = document.getElementById('related_account_id');
    const relatedHelpEl = document.getElementById('related_account_help');
    const categoryEl = document.getElementById('category_id');
    const merchantEl = document.getElementById('merchant_name');
    const suggestBoxEl = document.getElementById('category_suggest_box');

    const installmentEl = document.getElementById('is_installment');
    const installmentWrapEl = document.getElementById('installment_months_wrap');
    const installmentMonthsEl = document.getElementById('installment_months');
    const installmentRateWrapEl = document.getElementById('installment_rate_wrap');
    const installmentRateEl = document.getElementById('installment_interest_rate');
    const installmentInterestWrapEl = document.getElementById('installment_interest_wrap');
    const installmentTotalWrapEl = document.getElementById('installment_total_wrap');
    const installmentInterestEl = document.getElementById('installment_interest_total');
    const installmentTotalEl = document.getElementById('installment_total_billed');
    const amountEl = document.getElementById('amount');

    const quickAmtButtons = document.querySelectorAll('.quick-amt');
    const amountClearBtn = document.getElementById('amount_clear_btn');

    const allCategoryOptions = Array.from(categoryEl.querySelectorAll('option')).map(option => ({
        value: option.value,
        text: option.textContent,
        type: option.dataset.type
    }));

    let suggestTimer = null;
    let lastSuggestedCategoryId = null;

    function parseNumber(value) {
        const normalized = String(value || '').replace(/,/g, '').trim();
        const n = parseFloat(normalized);
        return isNaN(n) ? 0 : n;
    }

    function formatWithComma(value) {
        const normalized = String(value || '').replace(/,/g, '').replace(/[^\d.]/g, '');
        if (normalized === '') return '';
        const parts = normalized.split('.');
        parts[0] = parts[0].replace(/\B(?=(\d{3})+(?!\d))/g, ',');
        return parts.join('.');
    }

    function selectedAccount() {
        const id = parseInt(accountEl.value || '0', 10);
        return ACCOUNTS.find(a => a.id === id) || null;
    }

    function mapTransactionTypeToCategoryType(transactionType) {
        if (transactionType === 'income') return 'income';
        if (transactionType === 'expense') return 'expense';
        return 'transfer';
    }

    function rebuildCategoryOptions() {
        const transactionType = transactionTypeEl.value;
        const categoryType = mapTransactionTypeToCategoryType(transactionType);
        const currentValue = categoryEl.value;
        const filtered = allCategoryOptions.filter(item => item.type === categoryType);

        categoryEl.innerHTML = '<option value="0">선택하세요</option>';

        filtered.forEach((item) => {
            const option = document.createElement('option');
            option.value = item.value;
            option.textContent = item.text;
            if (item.value === currentValue) option.selected = true;
            categoryEl.appendChild(option);
        });

        if (![...categoryEl.options].some(opt => opt.value === currentValue)) {
            categoryEl.value = '0';
        }
    }

    function filterRelatedAccountOptions() {
        const transactionType = transactionTypeEl.value;
        const mainAccountType = accountEl.selectedOptions[0]?.dataset.accountType || '';
        const mainAccountId = accountEl.value;

        Array.from(relatedAccountEl.options).forEach(option => {
            if (option.value === '') {
                option.hidden = false;
                return;
            }

            const optionType = option.dataset.accountType || '';
            let visible = true;

            if (option.value === mainAccountId) {
                visible = false;
            } else if (transactionType === 'transfer') {
                visible =
                    ['bank', 'cash', 'other'].includes(mainAccountType) &&
                    ['bank', 'cash', 'other'].includes(optionType);
            } else if (transactionType === 'card_payment') {
                visible =
                    ['bank', 'cash', 'other'].includes(mainAccountType) &&
                    optionType === 'card';
            }

            option.hidden = !visible;

            if (!visible && option.selected) {
                relatedAccountEl.value = '';
            }
        });

        if (transactionType === 'transfer') {
            relatedAccountEl.disabled = false;
            relatedAccountEl.required = true;
            relatedHelpEl.textContent = '같은 주 계좌는 제외되고, 입금 계좌만 선택 가능합니다.';
        } else if (transactionType === 'card_payment') {
            relatedAccountEl.disabled = false;
            relatedAccountEl.required = true;
            relatedHelpEl.textContent = '관련 계좌에는 카드 계정만 선택 가능합니다.';
        } else {
            relatedAccountEl.disabled = true;
            relatedAccountEl.required = false;
            relatedAccountEl.value = '';
            relatedHelpEl.textContent = '계좌이체/카드대금납부 시 선택';
        }
    }

    function updateAccountHelpText() {
        const acc = selectedAccount();
        if (!acc) {
            accountHelpTextEl.textContent = '';
            return;
        }

        if (acc.type === 'card' && acc.card_kind === 'check') {
            accountHelpTextEl.textContent = '체크카드 · 즉시 출금 기준';
            return;
        }

        if (acc.type === 'card' && acc.card_kind === 'credit' && acc.use_credit_grace_period) {
            const billingDay = acc.billing_day ? `${acc.billing_day}일` : '-';
            const paymentDay = acc.payment_day ? `${acc.payment_day}일` : '-';
            accountHelpTextEl.textContent = `신용카드 · 결제기준일 ${billingDay} / 납부일 ${paymentDay}`;
            return;
        }

        accountHelpTextEl.textContent = '';
    }

    function calculateInterest() {
        const principal = parseNumber(amountEl.value);
        const months = parseInt(installmentMonthsEl.value || '0', 10) || 0;
        const annualRate = parseFloat(installmentRateEl.value || '0') || 0;

        if (principal <= 0 || months <= 1 || annualRate <= 0) {
            if (!installmentInterestEl.dataset.userEdited) {
                installmentInterestEl.value = '';
            }
            syncInstallmentTotal();
            return;
        }

        const monthlyRate = (annualRate / 100) / 12;
        const averageOutstanding = principal / 2;
        const interestTotal = Math.round((averageOutstanding * monthlyRate * months));

        if (!installmentInterestEl.dataset.userEdited || installmentInterestEl.value === '') {
            installmentInterestEl.value = formatWithComma(interestTotal);
        }

        syncInstallmentTotal();
    }

    function syncInstallmentTotal() {
        const principal = parseNumber(amountEl.value);
        const interest = parseNumber(installmentInterestEl.value);
        const calculated = principal + interest;

        if (!installmentTotalEl.dataset.userEdited || installmentTotalEl.value === '') {
            installmentTotalEl.value = calculated > 0 ? formatWithComma(calculated) : '';
        }
    }

    function toggleInstallmentFields() {
        const transactionType = transactionTypeEl.value;
        const acc = selectedAccount();
        const mainAccountType = acc ? acc.type : '';
        const isExpenseCard = (transactionType === 'expense' && mainAccountType === 'card');

        if (isExpenseCard) {
            installmentEl.disabled = false;

            if (String(installmentEl.value) === '1') {
                installmentWrapEl.style.display = '';
                installmentRateWrapEl.style.display = '';
                installmentInterestWrapEl.style.display = '';
                installmentTotalWrapEl.style.display = '';
                installmentMonthsEl.required = true;
                calculateInterest();
            } else {
                installmentWrapEl.style.display = 'none';
                installmentRateWrapEl.style.display = 'none';
                installmentInterestWrapEl.style.display = 'none';
                installmentTotalWrapEl.style.display = 'none';
                installmentMonthsEl.required = false;
                installmentMonthsEl.value = '';
                installmentRateEl.value = '0';
                installmentInterestEl.value = '';
                installmentTotalEl.value = '';
                installmentInterestEl.dataset.userEdited = '';
                installmentTotalEl.dataset.userEdited = '';
            }
        } else {
            installmentEl.value = '0';
            installmentEl.disabled = true;
            installmentWrapEl.style.display = 'none';
            installmentRateWrapEl.style.display = 'none';
            installmentInterestWrapEl.style.display = 'none';
            installmentTotalWrapEl.style.display = 'none';
            installmentMonthsEl.required = false;
            installmentMonthsEl.value = '';
            installmentRateEl.value = '0';
            installmentInterestEl.value = '';
            installmentTotalEl.value = '';
            installmentInterestEl.dataset.userEdited = '';
            installmentTotalEl.dataset.userEdited = '';
        }
    }

    function hideSuggestBox() {
        suggestBoxEl.classList.add('d-none');
        suggestBoxEl.textContent = '';
        lastSuggestedCategoryId = null;
    }

    function showSuggestBox(message) {
        suggestBoxEl.textContent = message;
        suggestBoxEl.classList.remove('d-none');
    }

    async function fetchCategorySuggestion() {
        const merchantName = merchantEl.value.trim();
        const transactionType = transactionTypeEl.value;
        const categoryType = mapTransactionTypeToCategoryType(transactionType);

        if (merchantName.length < 2) {
            hideSuggestBox();
            return;
        }

        try {
            const url = `/api/category_suggest.php?merchant_name=${encodeURIComponent(merchantName)}&transaction_type=${encodeURIComponent(categoryType)}`;
            const response = await fetch(url, {
                headers: { 'X-Requested-With': 'XMLHttpRequest' }
            });

            if (!response.ok) {
                hideSuggestBox();
                return;
            }

            const result = await response.json();

            if (!result.ok || !result.found) {
                hideSuggestBox();
                return;
            }

            const targetOption = Array.from(categoryEl.options).find(option => option.value === String(result.category_id));
            if (!targetOption) {
                hideSuggestBox();
                return;
            }

            categoryEl.value = String(result.category_id);
            lastSuggestedCategoryId = String(result.category_id);
            showSuggestBox(`자동 추천: ${result.category_name} (규칙: ${result.keyword ?? result.pattern_text ?? ''})`);
        } catch (error) {
            hideSuggestBox();
        }
    }

    function scheduleSuggestion() {
        clearTimeout(suggestTimer);
        suggestTimer = setTimeout(fetchCategorySuggestion, 250);
    }

    quickAmtButtons.forEach(btn => {
        btn.addEventListener('click', function () {
            const current = parseNumber(amountEl.value);
            const add = parseInt(btn.dataset.add || '0', 10) || 0;
            amountEl.value = formatWithComma(current + add);
            calculateInterest();
        });
    });

    amountClearBtn.addEventListener('click', function () {
        amountEl.value = '';
        calculateInterest();
        amountEl.focus();
    });

    amountEl.addEventListener('input', function () {
        const cursorAtEnd = this.selectionStart === this.value.length;
        this.value = formatWithComma(this.value);
        if (cursorAtEnd) {
            this.setSelectionRange(this.value.length, this.value.length);
        }
        calculateInterest();
    });

    installmentInterestEl.addEventListener('input', function () {
        installmentInterestEl.dataset.userEdited = '1';
        installmentInterestEl.value = formatWithComma(installmentInterestEl.value);
        syncInstallmentTotal();
    });

    installmentTotalEl.addEventListener('input', function () {
        installmentTotalEl.dataset.userEdited = '1';
        installmentTotalEl.value = formatWithComma(installmentTotalEl.value);
    });

    transactionTypeEl.addEventListener('change', function () {
        rebuildCategoryOptions();
        filterRelatedAccountOptions();
        toggleInstallmentFields();
        scheduleSuggestion();
    });

    accountEl.addEventListener('change', function () {
        updateAccountHelpText();
        filterRelatedAccountOptions();
        toggleInstallmentFields();
    });

    installmentEl.addEventListener('change', toggleInstallmentFields);
    installmentMonthsEl.addEventListener('change', calculateInterest);
    installmentRateEl.addEventListener('input', calculateInterest);

    merchantEl.addEventListener('input', scheduleSuggestion);

    categoryEl.addEventListener('change', function () {
        if (lastSuggestedCategoryId && categoryEl.value !== lastSuggestedCategoryId) {
            hideSuggestBox();
        }
    });

    document.getElementById('transactionForm').addEventListener('submit', function () {
        amountEl.value = String(parseNumber(amountEl.value));
        installmentInterestEl.value = installmentInterestEl.value === '' ? '' : String(parseNumber(installmentInterestEl.value));
        installmentTotalEl.value = installmentTotalEl.value === '' ? '' : String(parseNumber(installmentTotalEl.value));
    });

    rebuildCategoryOptions();
    updateAccountHelpText();
    filterRelatedAccountOptions();
    toggleInstallmentFields();
})();
</script>

<?php require __DIR__ . '/../app/views/footer.php'; ?>