import $ from 'jquery';
import { JSONRPC } from '@/json-rpc.js';

const DNSMASQ_COMPONENT_NAME = 'ru.kirillius.pf.sdn.External.API.Components.DNSMASQ';

const FIELD_IDS = {
    container: 'dnsmasq-config-container',
    instancesList: 'dnsmasq-instances-list',
    addInstanceButton: 'dnsmasq-add-instance-btn',
    saveButton: 'save-dnsmasq-btn',
    status: 'dnsmasq-status-message'
};

const CLASS_NAMES = {
    instance: 'dnsmasq-instance-entry',
    removeInstanceButton: 'dnsmasq-remove-instance-btn',
    host: 'dnsmasq-host',
    user: 'dnsmasq-user',
    password: 'dnsmasq-password',
    forwarder: 'dnsmasq-forwarder'
};

const SELECTORS = {
    container: `#${FIELD_IDS.container}`,
    instancesList: `#${FIELD_IDS.instancesList}`,
    addInstanceButton: `#${FIELD_IDS.addInstanceButton}`,
    saveButton: `#${FIELD_IDS.saveButton}`,
    status: `#${FIELD_IDS.status}`
};

let currentConfig = { instances: [] };
let statusTimeoutId = null;
let instanceCounter = 0;

const getStatusElement = () => $(SELECTORS.status);

function normalizeConfig(config) {
    if (!config || !Array.isArray(config.instances)) {
        return { instances: [] };
    }

    return {
        instances: config.instances.map(instance => ({
            host: instance?.host || '127.0.0.1',
            user: instance?.user || '',
            password: instance?.password || '',
            forwarder: instance?.forwarder || '127.0.0.1'
        }))
    };
}

function clearStatus() {
    const $status = getStatusElement();
    if (!$status.length) {
        return;
    }
    if (statusTimeoutId) {
        clearTimeout(statusTimeoutId);
        statusTimeoutId = null;
    }
    $status.stop(true, true).hide().text('').removeClass('success-message error-message');
}

function updateStatus(message, type) {
    const $status = getStatusElement();
    if (!$status.length) {
        return;
    }
    if (statusTimeoutId) {
        clearTimeout(statusTimeoutId);
    }
    $status
        .removeClass('success-message error-message')
        .addClass(type === 'success' ? 'success-message' : 'error-message')
        .text(message)
        .show();

    statusTimeoutId = window.setTimeout(() => {
        $status.fadeOut();
    }, 5000);
}

async function runAction($button, pendingText, action, messages) {
    if (!$button.length) {
        return;
    }

    const originalText = $button.text();
    $button.prop('disabled', true).text(pendingText);
    clearStatus();

    try {
        const result = await action();
        if (messages?.success) {
            const successMessage = typeof messages.success === 'function'
                ? messages.success(result)
                : messages.success;
            if (successMessage) {
                updateStatus(successMessage, 'success');
            }
        }
    } catch (error) {
        console.error(messages?.log || 'Ошибка выполнения действия DNSMASQ:', error);
        if (messages?.error) {
            updateStatus(messages.error, 'error');
        }
    } finally {
        $button.prop('disabled', false).text(originalText);
    }
}

function resetCounters() {
    instanceCounter = 0;
}

function getNextInstanceId() {
    instanceCounter += 1;
    return instanceCounter;
}

function createInstanceRow(instance = {}) {
    const instanceId = getNextInstanceId();

    return `
        <div class="${CLASS_NAMES.instance}" data-instance-id="${instanceId}" style="border: 1px solid var(--color-border); padding: 20px; border-radius: 12px; margin-bottom: 20px; background: var(--color-surface, #1f2333);">
            <div style="display: flex; justify-content: space-between; align-items: center; margin-bottom: 16px;">
                <h4 style="margin: 0;">Инстанс</h4>
                <button type="button" class="btn-link ${CLASS_NAMES.removeInstanceButton}">Удалить</button>
            </div>
            <div class="form-group">
                <label for="dnsmasq-host-${instanceId}">Хост</label>
                <input type="text" id="dnsmasq-host-${instanceId}" class="form-control ${CLASS_NAMES.host}" placeholder="http://127.0.0.1:9090" value="${instance.host || '127.0.0.1'}">
            </div>
            <div class="form-group">
                <label for="dnsmasq-user-${instanceId}">Имя пользователя</label>
                <input type="text" id="dnsmasq-user-${instanceId}" class="form-control ${CLASS_NAMES.user}" value="${instance.user || ''}">
            </div>
            <div class="form-group">
                <label for="dnsmasq-password-${instanceId}">Пароль</label>
                <input type="password" id="dnsmasq-password-${instanceId}" class="form-control ${CLASS_NAMES.password}" placeholder="Оставьте пустым для сохранения текущего пароля" data-original-password="${instance.password || ''}">
            </div>
            <div class="form-group">
                <label for="dnsmasq-forwarder-${instanceId}">Forwarder</label>
                <input type="text" id="dnsmasq-forwarder-${instanceId}" class="form-control ${CLASS_NAMES.forwarder}" placeholder="127.0.0.1" value="${instance.forwarder || '127.0.0.1'}">
            </div>
        </div>
    `;
}

function populateInstances() {
    const instances = currentConfig.instances.length ? currentConfig.instances : [];
    const $list = $(SELECTORS.instancesList);
    resetCounters();
    $list.empty();
    instances.forEach(instance => {
        $list.append(createInstanceRow(instance));
    });
}

function renderDNSMASQForm() {
    const $container = $(SELECTORS.container);
    $container.html(`
        <div class="component-config-form">
            <h3 class="config-section-title">Инстансы DNSMASQ</h3>
            <p class="hint-text" style="margin-bottom: 20px;">Настройте параметры подключения к DNSMASQ для синхронизации списков серверов. Можно добавить несколько инстансов.</p>
            <div id="${FIELD_IDS.instancesList}"></div>
            <div class="form-group" style="margin-top: 10px;">
                <button type="button" id="${FIELD_IDS.addInstanceButton}" class="btn-secondary" style="width: 220px;">Добавить инстанс</button>
            </div>
            <div class="action-buttons" style="margin-top: 40px;">
                <button id="${FIELD_IDS.saveButton}" class="btn-primary" style="width: 220px;">Применить Конфигурацию</button>
            </div>
            <div id="${FIELD_IDS.status}" class="error-message" style="display: none; margin-top: 20px;"></div>
        </div>
    `);

    populateInstances();
    attachEventHandlers();
}

function collectConfigFromForm() {
    const instances = [];

    $(SELECTORS.instancesList).find(`.${CLASS_NAMES.instance}`).each((_, element) => {
        const $instance = $(element);

        const host = $instance.find(`.${CLASS_NAMES.host}`).val().trim();
        const user = $instance.find(`.${CLASS_NAMES.user}`).val().trim();
        const $passwordField = $instance.find(`.${CLASS_NAMES.password}`);
        const newPassword = $passwordField.val();
        const originalPassword = $passwordField.data('original-password') || '';
        const password = newPassword ? newPassword : originalPassword;
        const forwarder = $instance.find(`.${CLASS_NAMES.forwarder}`).val().trim();

        instances.push({
            host,
            user,
            password,
            forwarder
        });
    });

    return { instances };
}

async function loadConfig() {
    try {
        const fullConfig = await JSONRPC.System.getComponentConfig(DNSMASQ_COMPONENT_NAME);
        currentConfig = normalizeConfig(fullConfig);
        return true;
    } catch (error) {
        console.error('Ошибка при загрузке конфига DNSMASQ:', error);
        currentConfig = { instances: [] };
        return false;
    }
}

function handleAddInstance() {
    const $list = $(SELECTORS.instancesList);
    $list.append(createInstanceRow({
        host: '127.0.0.1',
        user: '',
        password: '',
        forwarder: '127.0.0.1'
    }));
}

function handleRemoveInstance(event) {
    event.preventDefault();
    $(event.currentTarget).closest(`.${CLASS_NAMES.instance}`).remove();
}

async function handleSave() {
    const $button = $(SELECTORS.saveButton);
    clearStatus();

    const newConfig = collectConfigFromForm();

    await runAction($button, 'Применение...', async () => {
        await JSONRPC.System.setComponentConfig(DNSMASQ_COMPONENT_NAME, newConfig);
        currentConfig = normalizeConfig(newConfig);
        populateInstances();
    }, {
        success: 'Конфигурация DNSMASQ успешно сохранена.',
        error: 'Ошибка при сохранении конфигурации DNSMASQ.',
        log: 'Ошибка сохранения конфига DNSMASQ'
    });
}

function attachEventHandlers() {
    $(SELECTORS.saveButton).off('click').on('click', handleSave);
    $(SELECTORS.addInstanceButton).off('click').on('click', handleAddInstance);
    $(SELECTORS.instancesList)
        .off('click', `.${CLASS_NAMES.removeInstanceButton}`).on('click', `.${CLASS_NAMES.removeInstanceButton}`, handleRemoveInstance);
}

function detachEventHandlers() {
    $(SELECTORS.saveButton).off('click');
    $(SELECTORS.addInstanceButton).off('click');
    $(SELECTORS.instancesList)
        .off('click', `.${CLASS_NAMES.removeInstanceButton}`);
}

export const DNSMASQConfig = {
    render: () => `
        <h1 class="page-title">Настройка DNSMASQ</h1>
        <div id="${FIELD_IDS.container}">
            <p>Загрузка конфигурации...</p>
        </div>
    `,
    mount: async () => {
        const success = await loadConfig();
        if (success) {
            renderDNSMASQForm();
        } else {
            $(SELECTORS.container).html('<p class="error-message">Не удалось загрузить конфигурацию DNSMASQ.</p>');
        }
    },
    unmount: () => {
        detachEventHandlers();
        clearStatus();
        currentConfig = { instances: [] };
    }
};