/*
	GoToSocial
	Copyright (C) GoToSocial Authors admin@gotosocial.org
	SPDX-License-Identifier: AGPL-3.0-or-later

	This program is free software: you can redistribute it and/or modify
	it under the terms of the GNU Affero General Public License as published by
	the Free Software Foundation, either version 3 of the License, or
	(at your option) any later version.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
	GNU Affero General Public License for more details.

	You should have received a copy of the GNU Affero General Public License
	along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

import React from "react";

import FormWithData from "../../lib/form/form-with-data";

import { useVerifyCredentialsQuery } from "../../lib/query/oauth";
import { useArrayInput, useTextInput } from "../../lib/form";
import { TextInput } from "../../components/form/inputs";
import useFormSubmit from "../../lib/form/submit";
import MutationButton from "../../components/form/mutation-button";
import { useAliasAccountMutation, useMoveAccountMutation } from "../../lib/query/user";
import { FormContext, useWithFormContext } from "../../lib/form/context";
import { store } from "../../redux/store";

export default function UserMigration() {
	return (
		<FormWithData
			dataQuery={useVerifyCredentialsQuery}
			DataForm={UserMigrationForm}
		/>
	);
}

function UserMigrationForm({ data: profile }) {
	return (
		<>
			<h2>Account Migration Settings</h2>
			<p>
				The following settings allow you to <strong>alias</strong> your account to
				another account elsewhere, or to <strong>move</strong> to another account.
			</p>
			<p>
				Account <strong>aliasing</strong> is harmless and reversible; you can
				set and unset up to five account aliases as many times as you wish.
			</p>
			<p>
				The account <strong>move</strong> action, on the other
				hand, has serious and irreversible consequences.
			</p>
			<p>
				For more information on account migration, please see <a href="https://docs.gotosocial.org/en/latest/user_guide/settings/#migration" target="_blank" className="docslink" rel="noreferrer">the documentation</a>.
			</p>
			<AliasForm data={profile} />
			<MoveForm data={profile} />
		</>
	);
}

function AliasForm({ data: profile }) {
	const form = {
		alsoKnownAs: useArrayInput("also_known_as_uris", {
			source: profile,
			valueSelector: (p) => (
				p.source?.also_known_as_uris
					? p.source?.also_known_as_uris.map(entry => [entry])
					: []
			),
			length: 5,
		}),
	};

	const [submitForm, result] = useFormSubmit(form, useAliasAccountMutation());
	
	return (
		<form className="user-migration-alias" onSubmit={submitForm}>
			<div className="form-section-docs">
				<h3>Alias Account</h3>
				<a
					href="https://docs.gotosocial.org/en/latest/user_guide/settings/#alias-account"
					target="_blank"
					className="docslink"
					rel="noreferrer"
				>
					Learn more about account aliasing (opens in a new tab)
				</a>
			</div>
			<AlsoKnownAsURIs
				field={form.alsoKnownAs}
			/>
			<MutationButton
				disabled={false}
				label="Save account aliases"
				result={result}
			/>
		</form>
	);
}

function AlsoKnownAsURIs({ field: formField }) {	
	return (
		<div className="aliases">
			<FormContext.Provider value={formField.ctx}>
				{formField.value.map((data, i) => (
					<AlsoKnownAsURI
						key={i}
						index={i}
						data={data}
					/>
				))}
			</FormContext.Provider>
		</div>
	);
}

function AlsoKnownAsURI({ index, data }) {	
	const name = `${index}`;
	const form = useWithFormContext(index, {
		alsoKnownAsURI: useTextInput(
			name,
			// Only one field per entry.
			{ defaultValue: data[0] ?? "" },
		),
	}); 

	return (
		<TextInput
			label={`Alias #${index+1}`}
			field={form.alsoKnownAsURI}
			placeholder={`https://example.org/users/my_other_account_${index+1}`}
		/>
	);
}

function MoveForm({ data: profile }) {
	let urlStr = store.getState().oauth.instanceUrl ?? "";
	let url = new URL(urlStr);
	
	const form = {
		movedToURI: useTextInput("moved_to_uri", {
			source: profile,
			valueSelector: (p) => p.moved?.url },
		),
		password: useTextInput("password"),
	};

	const [submitForm, result] = useFormSubmit(form, useMoveAccountMutation(), {
		changedOnly: false,
	});
	
	return (
		<form className="user-migration-move" onSubmit={submitForm}>
			<div className="form-section-docs">
				<h3>Move Account</h3>
				<p>
						For a move to be successful, you must have already set an alias from the
						target account back to the account you're moving from (ie., this account),
						using the settings panel of the instance on which the target account resides.
						To do this, provide the following details to the other instance: 
				</p>
				<dl className="migration-details">
					<div>
						<dt>Account handle/username:</dt>
						<dd>@{profile.acct}@{url.host}</dd>
					</div>
					<div>
						<dt>Account URI:</dt>
						<dd>{urlStr}/users/{profile.username}</dd>
					</div>
				</dl>
				<br/>
				<a
					href="https://docs.gotosocial.org/en/latest/user_guide/settings/#move-account"
					target="_blank"
					className="docslink"
					rel="noreferrer"
				>
						Learn more about moving your account (opens in a new tab)
				</a>
			</div>
			<TextInput
				disabled={false}
				field={form.movedToURI}
				label="Move target URI"
				placeholder="https://example.org/users/my_new_account"
			/>
			<TextInput
				disabled={false}
				type="password"
				name="password"
				field={form.password}
				label="Current account password"
			/>
			<MutationButton
				disabled={false}
				label="Confirm account move"
				result={result}
			/>
		</form>
	);
}