import { Identifier } from 'deepslate'
import { route } from 'preact-router'
import { useCallback, useEffect, useMemo, useRef, useState } from 'preact/hooks'
import config from '../../Config.js'
import { DRAFT_PROJECT, getProjectRoot, useLocale, useProject, useVersion } from '../../contexts/index.js'
import { useModal } from '../../contexts/Modal.jsx'
import { useSpyglass } from '../../contexts/Spyglass.jsx'
import { useFocus } from '../../hooks/useFocus.js'
import { cleanUrl, writeZip } from '../../Utils.js'
import { Btn } from '../Btn.js'
import { BtnMenu } from '../BtnMenu.js'
import { Octicon } from '../Octicon.jsx'
import type { TreeViewGroupRenderer, TreeViewLeafRenderer } from '../TreeView.js'
import { TreeView } from '../TreeView.js'
import { FileRenaming } from './FileRenaming.jsx'
import { ProjectCreation } from './ProjectCreation.jsx'
import { ProjectDeletion } from './ProjectDeletion.jsx'

export function ProjectPanel() {
	const { version } = useVersion()
	const { locale } = useLocale()
	const { showModal } = useModal()
	const { projects, project, projectUri, setProjectUri, changeProject } = useProject()
	const { client, service } = useSpyglass()

	const projectRoot = project ? getProjectRoot(project) : undefined

	const [entries, setEntries] = useState<string[]>()
	useEffect(() => {
		setEntries(undefined)
		if (!projectRoot) {
			return
		}
		client.fs.readdir(projectRoot).then(entries => {
			setEntries(entries.flatMap(e => {
				return e.isFile() ? [e.name.slice(projectRoot.length)] : []
			}))
		})
	}, [projectRoot])
	useEffect(() => {
		if (!service || !projectRoot) {
			return
		}
		service.watchTree(projectRoot, setEntries)
		return () => service.unwatchTree(projectRoot, setEntries)
	}, [service, projectRoot])

	const download = useRef<HTMLAnchorElement>(null)

	const onDownload = async () => {
		if (!download.current || entries === undefined || !project) {
			return
		}
		const zipEntries = await Promise.all(entries.map(async e => {
			const data = await client.fs.readFile(projectRoot + e)
			return [e, data] as [string, Uint8Array]
		}))
		if (!zipEntries.some(e => e[0] === 'pack.mcmeta')) {
			const packFormat = config.versions.find(v => v.id === version)!.pack_format
			const packMcmeta = { pack: { description: project.name, pack_format: packFormat } }
			const data = new TextEncoder().encode(JSON.stringify(packMcmeta, null, 2))
			zipEntries.push(['pack.mcmeta', data])
		}
		const url = await writeZip(zipEntries)
		download.current.setAttribute('href', url)
		download.current.setAttribute('download', `${project.name.replaceAll(' ', '_')}.zip`)
		download.current.click()
	}

	const onDeleteProject = useCallback(() => {
		showModal(() => <ProjectDeletion />)
	}, [])

	const onCreateProject = useCallback(() => {
		showModal(() => <ProjectCreation />)
	}, [])

	const actions = useMemo(() => [
		{
			icon: 'pencil',
			label: locale('project.rename_file'),
			onAction: (uri: string) => {
				const res = service?.dissectUri(uri)
				if (res) {
					// This is pretty hacky, improve this in the future when spyglass has a "constructUri" function
					const oldSuffix = `${res.pack}/${res.namespace}/${res.path}/${res.identifier}${res.ext}`
					if (!uri.endsWith(oldSuffix)) {
						console.warn(`Expected ${uri} to end with ${oldSuffix}`)
						return
					}
					const onRename = (newId: string) => {
						const prefix = uri.substring(0, uri.length - oldSuffix.length)
						const { namespace, path } = Identifier.parse(newId)
						const newUri = prefix + `${res.pack}/${namespace}/${res.path}/${path}${res.ext}`
						service?.renameFile(uri, newUri).then(() => {
							setProjectUri(newUri)
						})
					}
					showModal(() => <FileRenaming oldId={`${res.namespace}:${res.identifier}`} onRename={onRename} />)
				}
			},
		},
		{
			icon: 'trashcan',
			label: locale('project.delete_file'),
			onAction: (uri: string) => {
				client.fs.unlink(uri).then(() => {
					setProjectUri(undefined)
				})
			},
		},
	], [client, service, projectRoot, showModal])

	const FolderEntry: TreeViewGroupRenderer = useCallback(({ name, open, onClick }) => {
		return <div class="entry" onClick={onClick} >
			{Octicon[!open ? 'chevron_right' : 'chevron_down']}
			<span class="overflow-hidden text-ellipsis whitespace-nowrap">{name}</span>
		</div>
	}, [])

	const FileEntry: TreeViewLeafRenderer<string> = useCallback(({ entry }) => {
		const [focused, setFocus] = useFocus()
		const uri = projectRoot + entry
		const onContextMenu = (evt: MouseEvent) => {
			evt.preventDefault()
			setFocus()
		}
		const onClick = () => {
			const category = uri.endsWith('/pack.mcmeta')
				? 'pack_mcmeta'
				: service?.dissectUri(uri)?.category
			const gen = config.generators.find(g => g.id === category)
			if (!gen) {
				throw new Error(`Cannot find generator for uri ${uri}`)
			}
			route(cleanUrl(gen.url))
			setProjectUri(uri)
		}

		return <div class={`entry ${uri === projectUri ? 'active' : ''} ${focused ? 'focused' : ''}`} onClick={onClick} onContextMenu={onContextMenu} >
			{Octicon.file}
			<span>{entry.split('/').at(-1)}</span>
			{focused && <div class="entry-menu">
				{actions?.map(a => <div class="action [&>svg]:inline" onClick={e => { a.onAction(uri); e.stopPropagation(); setFocus(false) }}>
					{(Octicon as any)[a.icon]}
					<span>{a.label}</span>
				</div>)}
			</div>}
		</div>
	}, [service, actions, projectRoot, projectUri])

	return <div class="panel-content">
		<div class="project-controls">
			<BtnMenu icon="chevron_down" label={project ? project.name : locale('loading')} tooltip={locale('switch_project')} tooltipLoc="se">
				{projects.map(p => <Btn label={p.name} active={p.name === project?.name} onClick={() => changeProject(p.name)} />)}
			</BtnMenu>
			<BtnMenu icon="kebab_horizontal" >
				<Btn icon="file_zip" label={locale('project.download')} onClick={onDownload} />
				<Btn icon="plus_circle" label={locale('project.new')} onClick={onCreateProject} />
				{(project && project.name !== DRAFT_PROJECT.name) && <Btn icon="trashcan" label={locale('project.delete')} onClick={onDeleteProject} />}
			</BtnMenu>
		</div>
		<div class="project-files">
			{entries === undefined
				? <div class="p-2 flex flex-col gap-2">
					<div class="skeleton-2 rounded h-4 w-24"></div>
					<div class="skeleton-2 rounded h-4 w-32 ml-4"></div>
					<div class="skeleton-2 rounded h-4 w-24 ml-8"></div>
					<div class="skeleton-2 rounded h-4 w-36 ml-8"></div>
					<div class="skeleton-2 rounded h-4 w-28"></div>
				</div>
				: entries.length === 0
					? <span>{locale('project.no_files')}</span>
					: <TreeView entries={entries} split={path => path.split('/')} group={FolderEntry} leaf={FileEntry} />}
		</div>
		<a ref={download} style="display: none;"></a>
	</div>
}