import { ROOT_NODE } from 'node_store'
import { CustomHTMLElement } from './lib/custom_html_element.mjs'
import { N2Tree } from 'tree'
import { Node } from 'node'

export class App {
	constructor() {// {{{
		this.currentNode = null
		this.tree = new N2Tree()
		this.crumbs = new N2Crumbs()
		this.crumbsElement = document.getElementById('crumbs')
		this.nodeUI = document.getElementById('note')

		_mbus.subscribe('TREE_TRUNK_FETCHED', async () => {
			document.getElementById('tree').append(this.tree.render())
			document.getElementById('tree-nodes')?.focus()

			const startNode = await this.getStartNode()
			this.goToNode(startNode.UUID, false, false)
		})

		_mbus.subscribe('TREE_NODE_SELECTED', event => {
			const node = event.detail.data
			this.goToNode(node.UUID, false, false)
		})

		_mbus.subscribe('GO_TO_NODE', event => {
			const node = event.detail.data
			this.goToNode(node.nodeUUID, node.dontPush, node.dontExpand)
		})

		window.addEventListener('keydown', event => this.keyHandler(event))
		window.addEventListener('popstate', event => this.popState(event))
		document.getElementById('notes2').addEventListener('click', event => {
			if (event.target.id === 'notes2')
				document.getElementById('node-content')?.focus()
		})

		window._sync = new Sync()

		// I think it is uncomfortable having the sync running as soon as the page load.
		// I haven't gotten the time to look at the page before stuff jumps around.
		// There a slight delay to initiate sync seems reasonable.
		setTimeout(() => window._sync.run(), 1000)
	}// }}}

	keyHandler(event) {//{{{
		let handled = true

		// All keybindings is Alt+Shift, since the popular browsers at the time (2023) allows to override thees.
		// Ctrl+S is the exception to using Alt+Shift, since it is overridable and in such widespread use for saving.
		// Thus, the exception is acceptable to consequent use of alt+shift.
		if (!(event.shiftKey && event.altKey) && !(event.key.toUpperCase() === 'S' && event.ctrlKey))
			return

		switch (event.key.toUpperCase()) {
			case 'T':
				if (document.activeElement.id === 'tree-nodes')
					this.nodeUI.takeFocus()
				else
					this.nodeUI.takeFocus()
				break

			case 'F':
				_mbus.dispatch('op-search')
				break
			/*
			case 'C':
				this.showPage('node')
				break

			case 'E':
				this.showPage('keys')
				break

			case 'M':
				this.toggleMarkdown()
				break

			*/
			case 'N':
				this.createNode()
				break

			/*
			case 'P':
				this.showPage('node-properties')
				break

			*/
			case 'S':
				this.saveNode()
				/*
				else if (this.page.value === 'node-properties')
					this.nodeProperties.current.save()
					*/
				break
			/*

			case 'U':
				this.showPage('upload')
				break

			case 'F':
				this.showPage('search')
				break
				*/

			default:
				handled = false
		}

		if (handled) {
			event.preventDefault()
			event.stopPropagation()
		}
	}//}}}
	popState(event) {// {{{
		_mbus.dispatch("GO_TO_NODE", { nodeUUID: event.state.nodeUUID, dontPush: true, dontExpand: true })
	}// }}}
	async getStartNode() {//{{{
		let nodeUUID = ROOT_NODE

		// Is a UUID provided on the URI as an anchor?
		const parts = document.URL.split('#')
		if (parts[1]?.match(/^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/i))
			nodeUUID = parts[1]

		return await nodeStore.get(nodeUUID)
	}//}}}
	async saveNode() {//{{{
		if (!this.currentNode.isModified())
			return

		/* The node history is a local store for node history.
		 * This could be provisioned from the server or cleared if
		 * deemed unnecessary.
		 *
		 * The send queue is what will be sent back to the server
		 * to have a recorded history of the notes.
		   *
		 * A setting to be implemented in the future could be to
		 * not save the history locally at all. */
		const node = this.currentNode

		// The node is still in its old state and will present
		// the unmodified content to the node store.
		const history = nodeStore.nodesHistory.add(node)

		// Prepares the node object for saving.
		// Sets Updated value to current date and time.
		await node.save()

		// Updated node is added to the send queue to be stored on server.
		const sendQueue = nodeStore.sendQueue.add(node)

		// Updated node is saved to the primary node store.
		const nodeStoreAdding = nodeStore.add([node])

		await Promise.all([history, sendQueue, nodeStoreAdding])
	}//}}}
	async createNode() {//{{{
		let name = prompt("Name")
		if (!name)
			return

		const nn = Node.create(name, this.currentNode.UUID)
		nn.save()

		nodeStore.sendQueue.add(nn)
		nodeStore.add([nn])

	}//}}}
	async goToNode(nodeUUID, dontPush, dontExpand) {//{{{
		if (nodeUUID === null || nodeUUID === undefined)
			return

		// Don't switch notes until saved.
		if (this.nodeUI.isModified()) {
			if (!confirm("Changes not saved. Do you want to discard changes?"))
				return
		}

		if (!dontPush)
			history.pushState({ nodeUUID }, '', `/notes2#${nodeUUID}`)

		const node = nodeStore.node(nodeUUID)
		node.reset() // any modifications are discarded.

		this.currentNode = node
		this.tree.setSelected(node, dontExpand)

		const ancestors = await nodeStore.getNodeAncestry(node)
		_mbus.dispatch('CRUMBS_SET', ancestors, () => this.crumbsElement.replaceChildren(this.crumbs.render()))
		_mbus.dispatch('NODE_UI_OPEN', node)
		_mbus.dispatch('NODE_UNMODIFIED')

		// Scrolls node into view.
		this.tree.makeVisible(node)
	}//}}}
}

class N2Crumbs extends CustomHTMLElement {
	static {// {{{
		this.tmpl = document.createElement('template')
		this.tmpl.innerHTML = `
		`
	}// }}}
	constructor() {// {{{
		super()
		this.classList.add('crumbs')

		this.crumbs = []

		_mbus.subscribe('CRUMBS_SET', event => {
			this.crumbs = event.detail.data
		})
	}// }}}
	render() {// {{{
		const crumbs = this.crumbs.map(node =>
			new N2Crumb(
				node.get('Name'),
				node.UUID,
			)
		)

		const start = new N2Crumb('Start', ROOT_NODE)
		crumbs.push(start)

		this.replaceChildren(...crumbs.reverse())
		return this
	}// }}}
}
customElements.define('n2-crumbs', N2Crumbs)

class N2Crumb extends CustomHTMLElement {
	static {// {{{
		this.tmpl = document.createElement('template')
		this.tmpl.innerHTML = `
			<a data-el="link"></a>
		`
	}// }}}
	constructor(label, uuid) {// {{{
		super()
		this.classList.add('crumb')

		this.label = label
		this.uuid = uuid

		this.elLink.href = `/notes2#${this.uuid}`
		this.elLink.innerText = this.label
		this.elLink.addEventListener('click', () => _mbus.dispatch("GO_TO_NODE", { nodeUUID: this.uuid, dontPush: false, dontExpand: true }))
	}// }}}
}
customElements.define('n2-crumb', N2Crumb)

function tmpl(html) {// {{{
	const el = document.createElement('template')
	el.innerHTML = html
	return el.content.children
}// }}}

class Op {
	constructor(id) {// {{{
		this.id = id
		_mbus.subscribe(this.id, p => this.render(p))
	}// }}}
	render(html) {// {{{
		const op = document.getElementById('op')
		const t = document.createElement('template')
		t.innerHTML = `<dialog id="${this.id}" class="op">${html}</dialog>`
		op.replaceChildren(t.content)
		document.getElementById(this.id).showModal()
	}// }}}
	get(selector) {// {{{
		return document.querySelector(`#${this.id} ${selector}`)
	}// }}}
	bind(selector, event, fn) {// {{{
		this.get(selector).addEventListener(event, evt => fn(evt))
	}// }}}
}

class OpSearch extends Op {
	constructor() {// {{{
		super('op-search')
	}// }}}
	render() {// {{{
		super.render(`
			<div class="header">Search</div>
			<div>
				<input type="text" />
			</div>
			<div class="header">Results</div>
			<div class="results"></div>
		`)

		this.bind('input[type="text"]', 'keydown', evt => this.search(evt))
	}// }}}
	search(event) {// {{{
		if (event.key !== 'Enter')
			return

		const searchFor = document.querySelector('#op-search input').value
		nodeStore.search(searchFor, ROOT_NODE)
			.then(res => this.displayResults(res))
	}// }}}
	displayResults(results) {// {{{
		const rs = []
		for (const r of results) {
			const ancestors = r.ancestry.reverse().map(a => {
				const div = tmpl(`<div class="ancestor">${a.data.Name}</div>`)
				div[0].addEventListener('click', () => _notes2.current.goToNode(a.UUID))
				return div[0]
			})


			const div = tmpl(`<div>${r.name}</div>`)
			div[0].addEventListener('click', () => _notes2.current.goToNode(r.uuid))
			rs.push(...div)

			const ancDev = tmpl('<div class="ancestors"></div>')
			ancDev[0].append(...ancestors)
			rs.push(ancDev[0])
		}
		this.get('.results').replaceChildren(...rs)
	}// }}}
}

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