import React, { useEffect, useContext, useState } from "react";
import { useHistory, useParams } from "react-router-dom";
import { Button, Checkbox, Col, Form, Input, Popconfirm, Row, Space, Spin } from "antd";
import DeleteOutlined from "@ant-design/icons/DeleteOutlined";

import libLink from "@clusterio/lib/link";
import libUsers from "@clusterio/lib/users";

import ControlContext from "./ControlContext";
import PageLayout from "./PageLayout";
import { notifyErrorHandler } from "../util/notify";


function useRole(id) {
	let control = useContext(ControlContext);
	let [role, setRole] = useState({ loading: true });

	function updateRole() {
		// XXX optimize by requesting only the role in question
		libLink.messages.listRoles.send(control).then(result => {
			let match = result.list.find(u => u.id === id);
			if (!match) {
				setRole({ missing: true });
			} else {
				setRole({
					...match,
					present: true,
				});
			}
		});
	}

	useEffect(() => {
		updateRole();
	}, [id]);

	return [role, updateRole];
}

export default function RoleViewPage() {
	let params = useParams();
	let roleId = Number(params.id);

	let history = useHistory();

	let control = useContext(ControlContext);
	let [role, updateRole] = useRole(roleId);
	let [edited, setEdited] = useState(false);


	let nav = [{ name: "Roles", path: "/roles" }, { name: role["name"] || roleId }];
	if (role.loading) {
		return <PageLayout nav={nav}>
			<h2>{roleId}</h2>
			<Spin size="large" />
		</PageLayout>;
	}

	if (role.missing) {
		return <PageLayout nav={nav}>
			<h2>Role not found</h2>
			<p>Role with id {roleId} was not found on the master server.</p>
		</PageLayout>;
	}

	let initialValues = {
		name: role["name"],
		description: role["description"],
		permissions: {
			...Object.fromEntries([...libUsers.permissions.values()].map(perm => [
				perm.name, role["permissions"].includes(perm.name),
			])),
		},
	};

	return <PageLayout nav={nav}>
		<Form
			initialValues={initialValues}
			onValuesChange={() => { setEdited(true); }}
			onFinish={values => {
				let newPermissions = [];
				for (let [name, value] of Object.entries(values.permissions)) {
					if (value) { newPermissions.push(name); }
				}

				libLink.messages.updateRole.send(control, {
					id: roleId,
					name: values.name || "",
					description: values.description || "",
					permissions: newPermissions,
				}).then(() => {
					setEdited(false);
					updateRole();
				}).catch(notifyErrorHandler("Error applying changes"));
			}}
		>
			<Row>
				<Col flex="auto">
					<h2>{role["name"]}</h2>
				</Col>
				<Col flex="0 0 auto">
					<Space>
						<Button type={edited ? "primary" : "default"} htmlType="submit">
							Apply
						</Button>
						<Popconfirm
							title="Delete role?"
							placement="bottomRight"
							okText="Delete"
							okButtonProps={{ danger: true }}
							onConfirm={() => {
								libLink.messages.deleteRole.send(
									control, { id: roleId }
								).then(() => {
									history.push("/roles");
								}).catch(notifyErrorHandler("Error deleting role"));
							}}
						>
							<Button danger >
								<DeleteOutlined />
							</Button>
						</Popconfirm>
					</Space>
				</Col>
			</Row>
			<Form.Item name="name" label="Name">
				<Input/>
			</Form.Item>
			<Form.Item name="description" label="Description">
				<Input/>
			</Form.Item>
			<h3>Permissions</h3>
			{[...libUsers.permissions.values()].map(({name, title, description}) => (
				<Form.Item
					name={["permissions", name]}
					key={name}
					label={title}
					tooltip={description}
					valuePropName="checked"
					labelCol={{ sm: { span: 22, push: 2 }}}
					wrapperCol={{ sm: { span: 2, pull: 22 }}}
					labelAlign="left"
					colon={false}
				>
					<Checkbox/>
				</Form.Item>
			))}
		</Form>
	</PageLayout>;
}