/// <reference lib="dom" />

import { servers } from "./index.ts"
import { log } from "./logger.ts"
import { Room } from "./room.ts"
import { TrackHandle } from "./track_handle.ts";
import { User } from "./user.ts"

export class RemoteUser extends User {
    peer: RTCPeerConnection
    negotiation_busy = false

    constructor(room: Room, name: string) {
        super(room, name)
        log("usermodel", `added remote user: ${name}`)
        this.peer = new RTCPeerConnection(servers)
        this.peer.onicecandidate = ev => {
            if (!ev.candidate) return
            room.websocket_send({ ice_candiate: ev.candidate.toJSON(), receiver: this.name })
        }
        this.peer.ontrack = ev => {
            const t = ev.track
            log("media", `remote track: ${this.name}`, t)
            this.add_track(new TrackHandle(t))
        }
        this.peer.onnegotiationneeded = async () => {
            log("webrtc", `negotiation needed: ${this.name}`)
            while (this.negotiation_busy) {
                await new Promise<void>(r => setTimeout(() => r(), 100))
            }
            this.offer()
        }
    }

    async offer() {
        this.negotiation_busy = true
        const offer_description = await this.peer.createOffer()
        await this.peer.setLocalDescription(offer_description)
        const offer = { type: offer_description.type, sdp: offer_description.sdp }
        log("webrtc", `sent offer: ${this.name}`, { a: offer })
        this.room.websocket_send({ receiver: this.name, offer })
    }
    async on_offer(offer: RTCSessionDescriptionInit) {
        this.negotiation_busy = true
        log("webrtc", `got offer: ${this.name}`, { a: offer })
        const offer_description = new RTCSessionDescription(offer)
        await this.peer.setRemoteDescription(offer_description)
        this.answer()
    }
    async answer() {
        const answer_description = await this.peer.createAnswer()
        await this.peer.setLocalDescription(answer_description)
        const answer = { type: answer_description.type, sdp: answer_description.sdp }
        log("webrtc", `sent answer: ${this.name}`, { a: answer })
        this.room.websocket_send({ receiver: this.name, answer })
        this.negotiation_busy = false
    }
    async on_answer(answer: RTCSessionDescriptionInit) {
        log("webrtc", `got answer: ${this.name}`, { a: answer })
        const answer_description = new RTCSessionDescription(answer)
        await this.peer.setRemoteDescription(answer_description)
        this.negotiation_busy = false
    }

    add_ice_candidate(candidate: RTCIceCandidateInit) {
        this.peer.addIceCandidate(new RTCIceCandidate(candidate))
    }

    leave() {
        log("usermodel", `remove remote user: ${this.name}`)
        this.peer.close()
        this.room.el.removeChild(this.el)
    }
}