import {ElemJS} from "./basic.js"
import {Subscribable} from "./store/Subscribable.js"

class Event extends ElemJS {
	constructor(data) {
		super("div")
		this.class("c-message")
		this.data = null
		this.update(data)
	}

	update(data) {
		this.data = data
		this.render()
	}

	render() {
		this.child(this.data.content.body)
	}
}

class Timeline extends Subscribable {
	constructor() {
		super()
		Object.assign(this.events, {
			addItem: [],
			removeItem: []
		})
		Object.assign(this.eventDeps, {
			addItem: [],
			removeItem: []
		})
		this.list = []
		this.map = new Map()
		this.elementsMap = new Map()
		this.elementsList = []
	}

	_binarySearch(event, min = 0, max = -1) {
		if (this.list.length === 0) return {success: false, i: 0}

		if (max === -1) max = this.list.length - 1
		let mid = Math.floor((max + min) / 2)
		// success condition
		if (this.list[mid] && this.list[mid].event_id === event.event_id) return {success: true, i: mid}
		// failed condition
		if (min >= max) {
			while (mid !== -1 && (!this.list[mid] || this.list[mid].origin_server_ts > event.origin_server_ts)) mid--
			return {
				success: false,
				i: mid + 1
			}
		}
		// recurse (below)
		if (this.list[mid].origin_server_ts > event.origin_server_ts) return this._binarySearch(event, min, mid-1)
		// recurse (above)
		else return this._binarySearch(event, mid+1, max)
	}

	updateEvents(events) {
		for (const event of events) {
			if (this.map.has(event.event_id)) {
				this.map.set(event.event_id, event)
				this.elementsMap.get(event.event_id).update(this.map.get(event.event_id))
			} else {
				const index = this._binarySearch(event).i
				this.list.splice(index, 0, event)
				this.map.set(event.event_id, event)
				const e = new Event(event)
				this.elementsList.splice(index, 0, e)
				this.elementsMap.set(event.event_id, e)
				this.broadcast("addItem", {index, element: e})
			}
		}
	}

	getGroupedEvents() {
		let currentSender = Symbol("N/A")
		let groups = []
		let currentGroup = []
		for (const event of this.list) {
			if (event.sender === currentSender) {
				currentGroup.push(event)
			} else {
				if (currentGroup.length) groups.push(currentGroup)
				currentGroup = [event]
				currentSender = event.sender
			}
		}
		if (currentGroup.length) groups.push(currentGroup)
		return groups
	}
}

export {Timeline}