import { XCircle, Plus, Share, X, File } from "@styled-icons/boxicons-regular";
import styled from "styled-components";

import { Text } from "preact-i18n";
import { useEffect, useState } from "preact/hooks";

import { determineFileSize } from "../../../../lib/fileSize";

import { CAN_UPLOAD_AT_ONCE, UploadState } from "../MessageBox";

interface Props {
	state: UploadState;
	addFile: () => void;
	removeFile: (index: number) => void;
}

const Container = styled.div`
	gap: 4px;
	padding: 8px;
	display: flex;
	user-select: none;
	flex-direction: column;
	background: var(--message-box);
`;

const Carousel = styled.div`
	gap: 8px;
	display: flex;
	overflow-x: scroll;
	flex-direction: row;
`;

const Entry = styled.div`
	display: flex;
	flex-direction: column;

	&.fade {
		opacity: 0.4;
	}

	span.fn {
		margin: auto;
		font-size: 0.8em;
		overflow: hidden;
		max-width: 180px;
		text-align: center;
		white-space: nowrap;
		text-overflow: ellipsis;
		color: var(--secondary-foreground);
	}

	span.size {
		font-size: 0.6em;
		color: var(--tertiary-foreground);
		text-align: center;
	}
`;

const Description = styled.div`
	gap: 4px;
	display: flex;
	font-size: 0.9em;
	align-items: center;
	color: var(--secondary-foreground);
`;

const Divider = styled.div`
	width: 4px;
	height: 130px;
	flex-shrink: 0;
	border-radius: 4px;
	background: var(--tertiary-background);
`;

const EmptyEntry = styled.div`
	width: 100px;
	height: 100px;
	display: grid;
	flex-shrink: 0;
	cursor: pointer;
	border-radius: 4px;
	place-items: center;
	background: var(--primary-background);
	transition: 0.1s ease background-color;

	&:hover {
		background: var(--secondary-background);
	}
`;

const PreviewBox = styled.div`
	display: grid;
	grid-template: "main" 100px / minmax(100px, 1fr);
	justify-items: center;

	background: var(--primary-background);

	overflow: hidden;

	cursor: pointer;
	border-radius: 4px;

	.icon,
	.overlay {
		grid-area: main;
	}

	.icon {
		height: 100px;
		width: 100%;
		margin-bottom: 4px;
		object-fit: contain;
	}

	.overlay {
		display: grid;
		align-items: center;
		justify-content: center;

		width: 100%;
		height: 100%;

		opacity: 0;
		visibility: hidden;

		transition: 0.1s ease opacity;
	}

	&:hover {
		.overlay {
			visibility: visible;
			opacity: 1;
			background-color: rgba(0, 0, 0, 0.8);
		}
	}
`;

function FileEntry({
	file,
	remove,
	index,
}: {
	file: File;
	remove?: () => void;
	index: number;
}) {
	if (!file.type.startsWith("image/"))
		return (
			<Entry className={index >= CAN_UPLOAD_AT_ONCE ? "fade" : ""}>
				<PreviewBox onClick={remove}>
					<EmptyEntry className="icon">
						<File size={36} />
					</EmptyEntry>
					<div class="overlay">
						<XCircle size={36} />
					</div>
				</PreviewBox>
				<span class="fn">{file.name}</span>
				<span class="size">{determineFileSize(file.size)}</span>
			</Entry>
		);

	const [url, setURL] = useState("");

	useEffect(() => {
		let url: string = URL.createObjectURL(file);
		setURL(url);
		return () => URL.revokeObjectURL(url);
	}, [file]);

	return (
		<Entry className={index >= CAN_UPLOAD_AT_ONCE ? "fade" : ""}>
			<PreviewBox onClick={remove}>
				<img class="icon" src={url} alt={file.name} />
				<div class="overlay">
					<XCircle size={36} />
				</div>
			</PreviewBox>
			<span class="fn">{file.name}</span>
			<span class="size">{determineFileSize(file.size)}</span>
		</Entry>
	);
}

export default function FilePreview({ state, addFile, removeFile }: Props) {
	if (state.type === "none") return null;

	return (
		<Container>
			<Carousel>
				{state.files.map((file, index) => (
					<>
						{index === CAN_UPLOAD_AT_ONCE && <Divider />}
						<FileEntry
							index={index}
							file={file}
							key={file.name}
							remove={
								state.type === "attached"
									? () => removeFile(index)
									: undefined
							}
						/>
					</>
				))}
				{state.type === "attached" && (
					<EmptyEntry onClick={addFile}>
						<Plus size={48} />
					</EmptyEntry>
				)}
			</Carousel>
			{state.type === "uploading" && (
				<Description>
					<Share size={24} />
					<Text id="app.main.channel.uploading_file" /> (
					{state.percent}%)
				</Description>
			)}
			{state.type === "sending" && (
				<Description>
					<Share size={24} />
					Sending...
				</Description>
			)}
			{state.type === "failed" && (
				<Description>
					<X size={24} />
					<Text id={`error.${state.error}`} />
				</Description>
			)}
		</Container>
	);
}