import {LitElement, html} from './lit-all.min.js';
import * as tfutils from './tf-utils.js';
import * as tfrpc from '/static/tfrpc.js';
import {styles} from './tf-styles.js';
import Tribute from './tribute.esm.js';

class TfComposeElement extends LitElement {
	static get properties() {
		return {
			whoami: {type: String},
			users: {type: Object},
			root: {type: String},
			branch: {type: String},
			mentions: {type: Object},
		}
	}

	static styles = styles;

	constructor() {
		super();
		this.users = {};
		this.root = undefined;
		this.branch = undefined;
		this.mentions = {};
	}

	changed(event) {
		let edit = this.renderRoot.getElementById('edit');
		let preview = this.renderRoot.getElementById('preview');
		let text = edit.value;

		/* Update mentions. */
		for (let match of text.matchAll(/\[([^\[]+)]\(([@&%][^\)]+)/g)) {
			let name = match[1];
			let link = match[2];
			let balance = 0;
			let bracket_end = match.index + match[1].length + '[]'.length - 1;
			for (let i = bracket_end; i >= 0; i--) {
				if (text.charAt(i) == ']') {
					balance++;
				} else if (text.charAt(i) == '[') {
					balance--;
				}
				if (balance <= 0) {
					name = text.substring(i + 1, bracket_end);
					break;
				}
			}
			if (!this.mentions[link]) {
				this.mentions[link] = {
					link: link,
				}
			}
			this.mentions[link].name = name.startsWith('@') ? name.substring(1) : name;
			this.mentions = Object.assign({}, this.mentions);
		}

		preview.innerHTML = tfutils.markdown(text);
	}

	add_file(file) {
		let self = this;
		file.arrayBuffer().then(function(buffer) {
			let bin = Array.from(new Uint8Array(buffer));
			return Promise.all([tfrpc.rpc.store_blob(bin), bin]);
		}).then(function([id, bin]) {
			self.mentions[id] = {
				link: id,
				name: file.name,
				type: file.type,
				size: bin.length,
			};
			self.mentions = Object.assign({}, self.mentions);
			let edit = self.renderRoot.getElementById('edit');
			edit.value += `\n![${file.name}](${id})`;
			self.changed();
		}).catch(function(e) {
			alert(e.message);
		});
	}

	paste(event) {
		let self = this;
		for(let item of event.clipboardData.items) {
			if (item.type?.startsWith('image/')) {
				let file = item.getAsFile();
				if (!file) {
					continue;
				}
				self.add_file(file);
				break;
			}
		}
	}

	submit() {
		let self = this;
		let edit = this.renderRoot.getElementById('edit');
		let message = {
			type: 'post',
			text: edit.value,
		};
		if (this.root || this.branch) {
			message.root = this.root;
			message.branch = this.branch;
		}
		if (Object.values(this.mentions).length) {
			message.mentions = Object.values(this.mentions);
		}
		console.log('Would post:', message);
		tfrpc.rpc.appendMessage(this.whoami, message).then(function() {
			edit.value = '';
			self.changed();
		}).catch(function(error) {
			alert(error.message);
		});
	}

	discard() {
		let edit = this.renderRoot.getElementById('edit');
		edit.value = '';
		this.changed();
		this.dispatchEvent(new CustomEvent('tf-discard'));
	}

	attach() {
		let self = this;
		let edit = this.renderRoot.getElementById('edit');
		let input = document.createElement('input');
		input.type = 'file';
		input.onchange = function(event) {
			let file = event.target.files[0];
			self.add_file(file);
		};
		input.click();
	}

	firstUpdated() {
		let tribute = new Tribute({
			values: Object.entries(this.users).map(x => ({key: x[1].name, value: x[0]})),
			selectTemplate: function(item) {
				return `[@${item.original.key}](${item.original.value})`;
			},
		});
		tribute.attach(this.renderRoot.getElementById('edit'));
	}

	remove_mention(id) {
		delete this.mentions[id];
		this.mentions = Object.assign({}, this.mentions);
	}

	render_mention(mention) {
		let self = this;
		return html`
			<div>
				<pre style="white-space: pre-wrap">${JSON.stringify(mention, null, 2)}</pre>
				<input type="button" value="x" @click=${() => self.remove_mention(mention.link)}></input>
			</div>`;
	}

	render() {
		let self = this;
		let result = html`
			<div style="display: flex; flex-direction: row; width: 100%">
				<textarea id="edit" @input=${this.changed} @paste=${this.paste} style="flex: 1 0 50%"></textarea>
				<div id="preview" style="flex: 1 0 50%"></div>
			</div>
			${Object.values(this.mentions).map(x => self.render_mention(x))}
			<input type="button" value="Submit" @click=${this.submit}></input>
			<input type="button" value="Attach" @click=${this.attach}></input>
			<input type="button" value="Discard" @click=${this.discard}></input>
		`;
		return result;
	}
}

customElements.define('tf-compose', TfComposeElement);