import {LitElement, cache, html, unsafeHTML, until} from './lit-all.min.js';
import * as tfrpc from '/static/tfrpc.js';
import {styles} from './tf-styles.js';

class TfTabNewsFeedElement extends LitElement {
	static get properties() {
		return {
			whoami: {type: String},
			users: {type: Object},
			hash: {type: String},
			following: {type: Array},
			messages: {type: Array},
			drafts: {type: Object},
			expanded: {type: Object},
			channels_unread: {type: Object},
			channels_latest: {type: Object},
			loading: {type: Number},
			time_range: {type: Array},
			time_loading: {type: Array},
		};
	}

	static styles = styles;

	constructor() {
		super();
		let self = this;
		this.whoami = null;
		this.users = {};
		this.hash = '#';
		this.following = [];
		this.drafts = {};
		this.expanded = {};
		this.channels_unread = {};
		this.channels_latest = {};
		this.start_time = new Date().valueOf();
		this.time_range = [0, 0];
		this.time_loading = undefined;
		this.loading = 0;
	}

	channel() {
		return this.hash.startsWith('##')
			? this.hash.substring(2)
			: this.hash.substring(1);
	}

	async fetch_messages(start_time, end_time) {
		this.time_loading = [start_time, end_time];
		let result;
		if (this.hash == '#@') {
			result = await tfrpc.rpc.query(
				`
					WITH mentions AS (SELECT messages.rowid, messages.id, messages.previous, messages.author, messages.sequence, messages.timestamp, messages.hash, json(messages.content) AS content, messages.signature
						FROM messages_fts(?1)
						JOIN messages ON messages.rowid = messages_fts.rowid
						JOIN json_each(?2) AS following ON messages.author = following.value
						WHERE
							messages.author != ?1 AND
							(?3 IS NULL OR messages.timestamp >= ?3) AND messages.timestamp < ?4
						ORDER BY timestamp DESC limit 20)
					SELECT FALSE AS is_primary, messages.rowid, messages.id, messages.previous, messages.author, messages.sequence, messages.timestamp, messages.hash, json(messages.content) AS content, messages.signature
						FROM mentions
						JOIN messages_refs ON mentions.id = messages_refs.ref
						JOIN messages ON messages_refs.message = messages.id
					UNION
					SELECT TRUE AS is_primary, * FROM mentions
				`,
				[
					'"' + this.whoami.replace('"', '""') + '"',
					JSON.stringify(this.following),
					start_time,
					end_time,
				]
			);
		} else if (this.hash.startsWith('#@')) {
			result = await tfrpc.rpc.query(
				`
					WITH
						selected AS (SELECT rowid, id, previous, author, sequence, timestamp, hash, json(content) AS content, signature
							FROM messages
							WHERE messages.author = ?1 AND (?2 IS NULL OR messages.timestamp >= 2) AND messages.timestamp < ?3
							ORDER BY sequence DESC LIMIT 20
						)
					SELECT FALSE AS is_primary, messages.rowid, messages.id, messages.previous, messages.author, messages.sequence, messages.timestamp, messages.hash, json(messages.content) AS content, messages.signature
						FROM selected
						JOIN messages_refs ON selected.id = messages_refs.ref
						JOIN messages ON messages_refs.message = messages.id
					UNION
					SELECT TRUE AS is_primary, * FROM selected
				`,
				[this.hash.substring(1), start_time, end_time]
			);
		} else if (this.hash.startsWith('#%')) {
			result = await tfrpc.rpc.query(
				`
					SELECT TRUE AS is_primary, id, previous, author, sequence, timestamp, hash, json(content) AS content, signature
					FROM messages
					WHERE messages.id = ?1
					UNION
					SELECT FALSE AS is_primary, id, previous, author, sequence, timestamp, hash, json(content) AS content, signature
					FROM messages JOIN messages_refs
					ON messages.id = messages_refs.message
					WHERE messages_refs.ref = ?1
				`,
				[this.hash.substring(1)]
			);
		} else if (this.hash.startsWith('##')) {
			result = await tfrpc.rpc.query(
				`
					WITH
						all_news AS (
							SELECT messages.rowid, messages.id, messages.previous, messages.author, messages.sequence, messages.timestamp, messages.hash, json(messages.content) AS content, messages.signature
								FROM messages
								JOIN json_each(?) AS following ON messages.author = following.value
								WHERE messages.content ->> 'channel' = ?4
							UNION
							SELECT messages.rowid, messages.id, messages.previous, messages.author, messages.sequence, messages.timestamp, messages.hash, json(messages.content) AS content, messages.signature
								FROM messages_fts(?5)
								JOIN messages ON messages.rowid = messages_fts.rowid
								JOIN json_each(?1) AS following ON messages.author = following.value
								JOIN json_tree(messages.content, '$.mentions') AS mention ON mention.value = '#' || ?4),
						news AS (SELECT * FROM all_news
							WHERE (?2 IS NULL OR all_news.timestamp >= ?2) AND all_news.timestamp < ?3
							ORDER BY all_news.timestamp DESC LIMIT 20)
					SELECT FALSE AS is_primary, messages.rowid, messages.id, messages.previous, messages.author, messages.sequence, messages.timestamp, messages.hash, json(messages.content) AS content, messages.signature
						FROM news
						JOIN messages_refs ON news.id = messages_refs.ref
						JOIN messages ON messages_refs.message = messages.id
					UNION
					SELECT FALSE AS is_primary, messages.rowid, messages.id, messages.previous, messages.author, messages.sequence, messages.timestamp, messages.hash, json(messages.content) AS content, messages.signature
						FROM news
						JOIN messages_refs ON news.id = messages_refs.message
						JOIN messages ON messages_refs.ref = messages.id
					UNION
					SELECT TRUE AS is_primary, news.* FROM news
				`,
				[
					JSON.stringify(this.following),
					start_time,
					end_time,
					this.hash.substring(2),
					'"#' + this.hash.substring(2).replace('"', '""') + '"',
				]
			);
		} else if (this.hash == '#🔐') {
			result = await tfrpc.rpc.query(
				`
					SELECT TRUE AS is_primary, messages.rowid, messages.id, previous, author, sequence, timestamp, hash, json(content) AS content, signature
						FROM messages
						JOIN json_each(?1) AS following ON messages.author = following.value
						WHERE
							(?2 IS NULL OR (messages.timestamp >= ?2) AND messages.timestamp < ?3 AND
							json(messages.content) LIKE '"%'
						ORDER BY sequence DESC LIMIT 20
				`,
				[JSON.stringify(this.following), start_time, end_time]
			);
			result = (await this.decrypt(result)).filter((x) => x.decrypted);
		} else {
			result = await tfrpc.rpc.query(
				`
					WITH
						all_news AS (
							SELECT messages.rowid, messages.id, messages.previous, messages.author, messages.sequence, messages.timestamp, messages.hash, json(messages.content) AS content, messages.signature
							FROM messages
							JOIN json_each(?) AS following ON messages.author = following.value
							WHERE timestamp >= 0 AND timestamp < ?3),
						news AS (
							SELECT * FROM all_news
							WHERE (?2 IS NULL OR all_news.timestamp >= ?2) AND all_news.timestamp < ?3
							ORDER BY timestamp DESC LIMIT 20
						)
					SELECT FALSE AS is_primary, messages.rowid, messages.id, messages.previous, messages.author, messages.sequence, messages.timestamp, messages.hash, json(messages.content) AS content, messages.signature
						FROM news
						JOIN messages_refs ON news.id = messages_refs.ref
						JOIN messages ON messages_refs.message = messages.id
					UNION
					SELECT FALSE AS is_primary, messages.rowid, messages.id, messages.previous, messages.author, messages.sequence, messages.timestamp, messages.hash, json(messages.content) AS content, messages.signature
						FROM news
						JOIN messages_refs ON news.id = messages_refs.message
						JOIN messages ON messages_refs.ref = messages.id
					UNION
					SELECT TRUE AS is_primary, news.* FROM news
				`,
				[JSON.stringify(this.following), start_time, end_time]
			);
		}
		this.time_loading = undefined;
		return result;
	}

	update_time_range_from_messages(messages) {
		let only_primary = messages.filter((x) => x.is_primary);
		this.time_range = [
			only_primary.reduce(
				(accumulator, current) => Math.min(accumulator, current.timestamp),
				this.time_range[0]
			),
			only_primary.reduce(
				(accumulator, current) => Math.max(accumulator, current.timestamp),
				this.time_range[1]
			),
		];
	}

	async load_more() {
		this.loading++;
		this.loading_canceled = false;
		try {
			let more = [];
			let last_start_time = this.time_range[0];
			more = await this.fetch_messages(null, last_start_time);
			this.update_time_range_from_messages(
				more.filter((x) => x.timestamp < last_start_time)
			);
			this.messages = await this.decrypt([...more, ...this.messages]);
		} finally {
			this.loading--;
		}
	}

	cancel_load() {
		this.loading_canceled = true;
	}

	async decrypt(messages) {
		let result = [];
		for (let message of messages) {
			let content;
			try {
				content = JSON.parse(message?.content);
			} catch {}
			if (typeof content === 'string') {
				let decrypted;
				try {
					decrypted = await tfrpc.rpc.try_decrypt(this.whoami, content);
				} catch {}
				if (decrypted) {
					try {
						message.decrypted = JSON.parse(decrypted);
					} catch {
						message.decrypted = decrypted;
					}
				}
			}
			result.push(message);
		}
		return result;
	}

	merge_messages(old_messages, new_messages) {
		let old_by_id = Object.fromEntries(old_messages.map((x) => [x.id, x]));
		return new_messages.map((x) => (old_by_id[x.id] ? old_by_id[x.id] : x));
	}

	async load_latest() {
		this.loading++;
		let now = new Date().valueOf();
		let end_time = now + 24 * 60 * 60 * 1000;
		let messages = [];
		try {
			messages = await this.fetch_messages(this.time_range[0], end_time);
			messages = await this.decrypt(messages);
			this.update_time_range_from_messages(
				messages.filter(
					(x) => x.timestamp >= this.time_range[0] && x.timestamp < end_time
				)
			);
		} finally {
			this.loading--;
		}
		this.messages = this.merge_messages(
			this.messages,
			Object.values(
				Object.fromEntries(
					[...this.messages, ...messages]
						.sort((x, y) => x.timestamp - y.timestamp)
						.slice(-1024)
						.map((x) => [x.id, x])
				)
			)
		);
		console.log('done loading latest messages.');
	}

	async load_messages() {
		let start_time = new Date();
		let self = this;
		this.loading++;
		let messages = [];
		try {
			if (this._messages_hash !== this.hash) {
				this.messages = [];
				this._messages_hash = this.hash;
			}
			this._messages_following = this.following;
			let now = new Date().valueOf();
			let start_time = now - 24 * 60 * 60 * 1000;
			this.start_time = start_time;
			this.time_range = [this.start_time, now + 24 * 60 * 60 * 1000];
			messages = await this.fetch_messages(null, this.time_range[1]);
			this.update_time_range_from_messages(
				messages.filter((x) => x.timestamp < this.time_range[1])
			);
			messages = await this.decrypt(messages);
		} finally {
			this.loading--;
		}
		this.messages = this.merge_messages(this.messages, messages);
		this.time_loading = undefined;
		console.log(
			`loading messages done for ${self.whoami} in ${(new Date() - start_time) / 1000}s`
		);
	}

	mark_all_read() {
		let newest = this.messages.reduce(
			(accumulator, current) => Math.max(accumulator, current.rowid),
			this.channels_latest[this.channel()] ?? -1
		);
		if (newest >= 0) {
			this.dispatchEvent(
				new CustomEvent('channelsetunread', {
					bubbles: true,
					composed: true,
					detail: {
						channel: this.channel(),
						unread: newest + 1,
					},
				})
			);
		}
	}

	render() {
		if (
			!this.messages ||
			this._messages_hash !== this.hash ||
			JSON.stringify(this._messages_following) !==
				JSON.stringify(this.following)
		) {
			console.log(
				`loading messages for ${this.whoami} (following ${this.following.length})`
			);
			this.load_messages();
		}
		let more;
		if (!this.hash.startsWith('#%')) {
			more = html`
				<p>
					<button class="w3-button w3-theme-d1" @click=${this.mark_all_read}>
						Mark All Read
					</button>
					<button
						?disabled=${this.loading}
						class="w3-button w3-theme-d1"
						@click=${this.load_more}
					>
						Load More
					</button>
					<button
						class=${'w3-button w3-theme-d1' + (this.loading ? '' : ' w3-hide')}
						@click=${this.cancel_load}
					>
						Cancel
					</button>
					<span
						>Showing
						${new Date(
							this.time_loading
								? Math.min(this.time_loading[0], this.time_range[0])
								: this.time_range[0]
						).toLocaleDateString()}
						-
						${new Date(
							this.time_loading
								? Math.max(this.time_loading[1], this.time_range[1])
								: this.time_range[1]
						).toLocaleDateString()}.</span
					>
				</p>
			`;
		}
		return cache(html`
			<button class="w3-button w3-theme-d1" @click=${this.mark_all_read}>
				Mark All Read
			</button>
			<tf-news
				id="news"
				whoami=${this.whoami}
				.users=${this.users}
				.messages=${this.messages}
				.following=${this.following}
				.drafts=${this.drafts}
				.expanded=${this.expanded}
				channel=${this.channel()}
				channel_unread=${this.channels_unread?.[this.channel()]}
			></tf-news>
			${more}
		`);
	}
}

customElements.define('tf-tab-news-feed', TfTabNewsFeedElement);