const MagicLink = require('@tryghost/magic-link');
const {URL} = require('url');
const path = require('path');
const urlUtils = require('../../../shared/url-utils');
const settingsCache = require('../../../shared/settings-cache');
const logging = require('@tryghost/logging');
const mail = require('../mail');
const updateEmailTemplate = require('./emails/updateEmail');
const SingleUseTokenProvider = require('./SingleUseTokenProvider');
const models = require('../../models');
const MAGIC_LINK_TOKEN_VALIDITY = 24 * 60 * 60 * 1000;

const ghostMailer = new mail.GhostMailer();

function createSettingsInstance(config) {
    const {transporter, getSubject, getText, getHTML, getSigninURL} = {
        transporter: {
            sendMail(message) {
                if (process.env.NODE_ENV !== 'production') {
                    logging.warn(message.text);
                }
                let msg = Object.assign({
                    from: config.getAuthEmailFromAddress(),
                    subject: 'Update email address',
                    forceTextContent: true
                }, message);

                return ghostMailer.send(msg);
            }
        },
        getSubject() {
            return `Confirm your email address`;
        },
        getText(url, type, email) {
            return `
            Hey there,

            Please confirm your email address with this link:

            ${url}

            For your security, the link will expire in 24 hours time.

            ---

            Sent to ${email}
            If you did not make this request, you can simply delete this message. This email address will not be used.
            `;
        },
        getHTML(url, type, email) {
            const siteTitle = settingsCache.get('title');
            return updateEmailTemplate({url, email, siteTitle});
        },
        getSigninURL(token, type) {
            const signinURL = new URL(getApiUrl({version: 'v4', type: 'admin'}));
            signinURL.pathname = path.join(signinURL.pathname, '/settings/members/email/');
            signinURL.searchParams.set('token', token);
            signinURL.searchParams.set('action', type);
            return signinURL.href;
        }
    };

    const getApiUrl = ({version, type}) => {
        return urlUtils.urlFor('api', {version: version, versionType: type}, true);
    };

    const magicLinkService = new MagicLink({
        transporter,
        tokenProvider: new SingleUseTokenProvider(models.SingleUseToken, MAGIC_LINK_TOKEN_VALIDITY),
        getSigninURL,
        getText,
        getHTML,
        getSubject
    });

    const sendEmailAddressUpdateMagicLink = ({email, type = 'fromAddressUpdate'}) => {
        const [,toDomain] = email.split('@');
        let fromEmail = `noreply@${toDomain}`;
        if (fromEmail === email) {
            fromEmail = `no-reply@${toDomain}`;
        }
        magicLinkService.transporter = {
            sendMail(message) {
                if (process.env.NODE_ENV !== 'production') {
                    logging.warn(message.text);
                }
                let msg = Object.assign({
                    from: fromEmail,
                    subject: 'Update email address',
                    forceTextContent: true
                }, message);

                return ghostMailer.send(msg);
            }
        };
        return magicLinkService.sendMagicLink({email, tokenData: {email}, subject: email, type});
    };

    const getEmailFromToken = async ({token}) => {
        const data = await magicLinkService.getDataFromToken(token);
        return data.email;
    };

    const getAdminRedirectLink = ({type}) => {
        const adminUrl = urlUtils.urlFor('admin', true);
        return urlUtils.urlJoin(adminUrl, `#/settings/members-email/?${type}=success`);
    };

    return {
        sendEmailAddressUpdateMagicLink,
        getEmailFromToken,
        getAdminRedirectLink
    };
}

module.exports = createSettingsInstance;