yosup/js/core.js

const KIND_METADATA = 0;
const KIND_NOTE     = 1;
const KIND_RELAY    = 2;
const KIND_CONTACT  = 3;
const KIND_DM       = 4;
const KIND_DELETE   = 5;
const KIND_SHARE    = 6;
const KIND_REACTION = 7;
const KIND_CHATROOM = 42;

const TAG_P = "#p";
const TAG_E = "#e";

const R_HEART = "❤️";
const R_SHAKA = "🤙";

const STANDARD_KINDS = [
	KIND_NOTE,
	KIND_DM,
	KIND_DELETE,
	KIND_REACTION,
	KIND_SHARE,
];
const PUBLIC_KINDS = [
	KIND_NOTE,
	KIND_DELETE,
	KIND_REACTION,
	KIND_SHARE,
];

async function broadcast_related_events(ev) {
	ev.tags.reduce((evs, tag) => {
		// cap it at something sane
		if (evs.length >= 5)
			return evs
		const ev = get_tag_event(tag)
		if (!ev)
			return evs
		return evs
	}, [])
	.forEach((ev, i) => {
		// so we don't get rate limited
		setTimeout(() => {
			log_debug("broadcasting related event", ev)
			broadcast_event(ev)
		}, (i+1)*1200)
	});
}

function broadcast_event(ev) {
	DAMUS.pool.send(["EVENT", ev])
}

async function share(evid) {
	const model = DAMUS;
	const e = model.all_events[evid];
	if (!e)
		return;
	let ev = {
		kind: KIND_SHARE,
		created_at: new_creation_time(),
		pubkey: model.pubkey,
		content: JSON.stringify(e),
		tags: [["e", e.id], ["p", e.pubkey]],
	}
	ev.id = await nostrjs.calculate_id(ev);
	ev = await sign_event(ev);
	broadcast_event(ev);
	return ev;
}

async function update_profile(profile={}) {
	let ev = {
		kind: KIND_METADATA,
		created_at: new_creation_time(),
		pubkey: DAMUS.pubkey,
		content: JSON.stringify(profile),
		tags: [],
	};
	ev.id = await nostrjs.calculate_id(ev);
	ev = await sign_event(ev);
	broadcast_event(ev);
	return ev;
}

async function update_contacts() {
	const model = DAMUS;
	const contacts = Array.from(model.contacts.friends);
	const tags = contacts.map((pubkey) => {
		return ["p", pubkey]
	});
	let ev = {
		kind: KIND_CONTACT,
		created_at: new_creation_time(),
		pubkey: model.pubkey,
		content: "",
		tags: tags,
	}
	ev.id = await nostrjs.calculate_id(ev);
	ev = await sign_event(ev);
	broadcast_event(ev);
	return ev;
}

async function sign_event(ev) {
	if (!(window.nostr && window.nostr.signEvent)) {
		console.error("window.nostr.signEvent is unsupported");
		return;
	}
	const signed = await window.nostr.signEvent(ev)
	if (typeof signed === 'string') {
		ev.sig = signed
		return ev
	}
	return signed
}

function new_reply_tags(ev) {
	const tags = [["e", ev.id, "", "reply"]];
	if (ev.refs.root) {
		tags.push(["e", ev.refs.root, "", "root"]);	
	}
	tags.push(["p", ev.pubkey]);
	return tags;
}

async function create_reply(pubkey, content, ev, all=true) {
	let kind = ev.kind;
	let tags = [];
	if (is_valid_reaction_content(content)) {
		// convert emoji replies into reactions
		kind = KIND_REACTION;
		tags.push(["e", ev.id], ["p", ev.pubkey]);
	} else {
		tags = all ? gather_reply_tags(pubkey, ev) : new_reply_tags(ev);
	}
	const created_at = new_creation_time();
	let reply = { 
		pubkey, 
		tags, 
		content, 
		created_at, 
		kind 
	};
	reply.id = await nostrjs.calculate_id(reply)
	reply = await sign_event(reply)
	return reply
}

async function send_reply(content, replying_to, all=true) {
	const ev = DAMUS.all_events[replying_to]
	if (!ev)
		return;

	const pubkey = await get_pubkey()
	let reply = await create_reply(pubkey, content, ev, all)

	broadcast_event(reply)
	broadcast_related_events(reply)
}

async function create_deletion_event(pubkey, target, content="") {
	const created_at = Math.floor(new Date().getTime() / 1000)
	let kind = 5

	const tags = [["e", target]]
	let del = { pubkey, tags, content, created_at, kind }

	del.id = await nostrjs.calculate_id(del)
	del = await sign_event(del)
	return del
}

async function delete_post(id, reason) {
	const ev = DAMUS.all_events[id]
	if (!ev)
		return

	const pubkey = await get_pubkey()
	let del = await create_deletion_event(pubkey, id, reason)
	broadcast_event(del)
}

function model_get_reacts_to(model, pubkey, evid, emoji) {
	const r = model.reactions_to[evid];
	if (!r)
		return;
	for (const id of r.keys()) {
		if (model_is_event_deleted(model, id))
			continue;
		const reaction = model.all_events[id];
		if (!reaction || reaction.pubkey != pubkey)
			continue;
		if (emoji == get_reaction_emoji(reaction))
			return reaction;
	}
	return;
}

function get_reactions(model, evid) {
	const reactions_set = model.reactions_to[evid]
	if (!reactions_set)
		return ""

	let reactions = []
	for (const id of reactions_set.keys()) {
		if (model_is_event_deleted(model, id))
			continue
		const reaction = model.all_events[id]
		if (!reaction)
			continue
		reactions.push(reaction)
	}

	const groups = reactions.reduce((grp, r) => {
		const e = get_reaction_emoji(r)
		grp[e] = grp[e] || {}
		grp[e][r.pubkey] = r
		return grp
	}, {})

	return groups
}

function gather_reply_tags(pubkey, from) {
	let tags = []
	let ids = new Set()

	if (from.refs && from.refs.root) {
		tags.push(["e", from.refs.root, "", "root"])
		ids.add(from.refs.root)
	}

	tags.push(["e", from.id, "", "reply"])
	ids.add(from.id)

	for (const tag of from.tags) {
		if (tag.length >= 2) {
			if (tag[0] === "p" && tag[1] !== pubkey) {
				if (!ids.has(tag[1])) {
					tags.push(["p", tag[1]])
					ids.add(tag[1])
				}
			}
		}
	}
	if (from.pubkey !== pubkey && !ids.has(from.pubkey)) {
		tags.push(["p", from.pubkey])
	}
	return tags
}

function get_tag_event(tag) {
	const model = DAMUS;
	if (tag.length < 2)
		return null
	if (tag[0] === "e")
		return model.all_events[tag[1]]
	if (tag[0] === "p") {
		let profile = model_get_profile(model, tag[1]);
		if (profile.evid)
			return model.all_events[profile.evid];
	}
	return null
}

function* yield_etags(tags) {
	for (const tag of tags) {
		if (tag.length >= 2 && tag[0] === "e")
			yield tag
	}
}

function get_content_warning(tags) {
	for (const tag of tags) {
		if (tag.length >= 1 && tag[0] === "content-warning")
			return tag[1] || ""
	}
	return null
}

async function get_nip05_pubkey(email) {
	const [user, host] = email.split("@")
	const url = `https://${host}/.well-known/nostr.json?name=${user}`
	try {
		const res = await fetch(url)
		const json = await res.json()
		log_debug("nip05 data", json)
		return json.names[user]
	} catch (e) {
		log_error("fetching nip05 entry for %s", email, e)
		throw e
	}
}