import {LitElement, html, unsafeHTML, live} 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},
			apps: {type: Object},
			drafts: {type: Object},
			author: {type: String},
			channel: {type: String},
		};
	}

	static styles = styles;

	constructor() {
		super();
		this.users = {};
		this.root = undefined;
		this.branch = undefined;
		this.apps = undefined;
		this.drafts = {};
		this.author = undefined;
	}

	process_text(text) {
		if (!text) {
			return '';
		}
		/* Update mentions. */
		let draft = this.get_draft();
		let updated = false;
		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 (!draft.mentions) {
				draft.mentions = {};
			}
			if (!draft.mentions[link]) {
				draft.mentions[link] = {
					link: link,
				};
			}
			draft.mentions[link].name = name.startsWith('@')
				? name.substring(1)
				: name;
			updated = true;
		}
		if (updated) {
			setTimeout(() => this.notify(draft), 0);
		}
		return tfutils.markdown(text);
	}

	input(event) {
		let edit = this.renderRoot.getElementById('edit');
		let preview = this.renderRoot.getElementById('preview');
		preview.innerHTML = this.process_text(edit.innerText);
		let content_warning = this.renderRoot.getElementById('content_warning');
		let draft = this.get_draft();
		draft.text = edit.innerText;
		draft.content_warning = content_warning?.value;
		setTimeout(() => this.notify(draft), 0);
	}

	notify(draft) {
		this.dispatchEvent(
			new CustomEvent('tf-draft', {
				bubbles: true,
				composed: true,
				detail: {
					id: this.branch,
					draft: draft,
				},
			})
		);
	}

	convert_to_format(buffer, type, mime_type) {
		return new Promise(function (resolve, reject) {
			let img = new Image();
			img.onload = function () {
				let canvas = document.createElement('canvas');
				let width_scale = Math.min(img.width, 1024) / img.width;
				let height_scale = Math.min(img.height, 1024) / img.height;
				let scale = Math.min(width_scale, height_scale);
				canvas.width = img.width * scale;
				canvas.height = img.height * scale;
				let context = canvas.getContext('2d');
				context.drawImage(img, 0, 0, canvas.width, canvas.height);
				let data_url = canvas.toDataURL(mime_type);
				let result = atob(data_url.split(',')[1])
					.split('')
					.map((x) => x.charCodeAt(0));
				resolve(result);
			};
			img.onerror = function (event) {
				reject(new Error('Failed to load image.'));
			};
			let raw = Array.from(new Uint8Array(buffer))
				.map((b) => String.fromCharCode(b))
				.join('');
			let original = `data:${type};base64,${btoa(raw)}`;
			img.src = original;
		});
	}

	async add_file(file) {
		try {
			let draft = this.get_draft();
			let self = this;
			let buffer = await file.arrayBuffer();
			let type = file.type;
			if (type.startsWith('image/')) {
				let best_buffer;
				let best_type;
				for (let format of ['image/png', 'image/jpeg', 'image/webp']) {
					let test_buffer = await self.convert_to_format(
						buffer,
						file.type,
						format
					);
					if (!best_buffer || test_buffer.length < best_buffer.length) {
						best_buffer = test_buffer;
						best_type = format;
					}
				}
				buffer = best_buffer;
				type = best_type;
			} else {
				buffer = Array.from(new Uint8Array(buffer));
			}
			let id = await tfrpc.rpc.store_blob(buffer);
			let name = type.split('/')[0] + ':' + file.name;
			if (!draft.mentions) {
				draft.mentions = {};
			}
			draft.mentions[id] = {
				link: id,
				name: name,
				type: type,
				size: buffer.length ?? buffer.byteLength,
			};
			let edit = self.renderRoot.getElementById('edit');
			edit.innerText += `\n![${name}](${id})`;
			self.input();
		} catch (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;
			}
		}

		event.preventDefault();
		document.execCommand(
			'insertText',
			false,
			event.clipboardData.getData('text/plain')
		);
	}

	async submit() {
		let self = this;
		let draft = this.get_draft();
		let edit = this.renderRoot.getElementById('edit');
		let message = {
			type: 'post',
			text: edit.innerText,
			channel: this.channel,
		};
		if (this.root || this.branch) {
			message.root = this.root;
			message.branch = this.branch;
		}
		if (Object.values(draft.mentions || {}).length) {
			message.mentions = Object.values(draft.mentions);
		}
		if (draft.content_warning !== undefined) {
			message.contentWarning = draft.content_warning;
		}
		console.log('Would post:', message);
		if (draft.encrypt_to) {
			let to = new Set(draft.encrypt_to);
			to.add(this.whoami);
			to = [...to];
			message.recps = to;
			console.log('message is now', message);
			message = await tfrpc.rpc.encrypt(
				this.whoami,
				to,
				JSON.stringify(message)
			);
			console.log('encrypted as', message);
		}
		try {
			await tfrpc.rpc.appendMessage(this.whoami, message);
			self.notify(undefined);
		} catch (error) {
			alert(error.message);
		}
	}

	discard() {
		this.notify(undefined);
	}

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

	async autocomplete(text, callback) {
		this.last_autocomplete = text;
		let results = [];
		try {
			let rows = await tfrpc.rpc.query(
				`
				SELECT json(messages.content) AS content FROM messages_fts(?)
				JOIN messages ON messages.rowid = messages_fts.rowid
				WHERE json(messages.content) LIKE ?
				ORDER BY timestamp DESC LIMIT 10
			`,
				['"' + text.replace('"', '""') + '"', `%![%${text}%](%)%`]
			);
			for (let row of rows) {
				for (let match of row.content.matchAll(/!\[([^\]]*)\]\((&.*?)\)/g)) {
					if (match[1].toLowerCase().indexOf(text.toLowerCase()) != -1) {
						results.push({key: match[1], value: match[2]});
					}
				}
			}
		} finally {
			if (this.last_autocomplete === text) {
				callback(results);
			}
		}
	}

	firstUpdated() {
		let values = Object.entries(this.users).map((x) => ({
			key: x[1].name ?? x[0],
			value: x[0],
		}));
		if (this.author) {
			values = [].concat(
				[
					{
						key: this.users[this.author]?.name,
						value: this.author,
					},
				],
				values
			);
		}
		let tribute = new Tribute({
			iframe: this.shadowRoot,
			collection: [
				{
					values: values,
					selectTemplate: function (item) {
						return item
							? `[@${item.original.key}](${item.original.value})`
							: undefined;
					},
				},
				{
					trigger: '&',
					values: this.autocomplete,
					selectTemplate: function (item) {
						return item
							? `![${item.original.key}](${item.original.value})`
							: undefined;
					},
				},
			],
		});
		tribute.attach(this.renderRoot.getElementById('edit'));
	}

	updated() {
		super.updated();
		let edit = this.renderRoot.getElementById('edit');
		if (this.last_updated_text !== edit.innerText) {
			let preview = this.renderRoot.getElementById('preview');
			preview.innerHTML = this.process_text(edit.innerText);
			this.last_updated_text = edit.innerText;
		}
		let encrypt = this.renderRoot.getElementById('encrypt_to');
		if (encrypt) {
			let tribute = new Tribute({
				iframe: this.shadowRoot,
				values: Object.entries(this.users).map((x) => ({
					key: x[1].name,
					value: x[0],
				})),
				selectTemplate: function (item) {
					return item.original.value;
				},
			});
			tribute.attach(encrypt);
		}
	}

	remove_mention(id) {
		let draft = this.get_draft();
		delete draft.mentions[id];
		setTimeout(() => this.notify(), 0);
	}

	render_mention(mention) {
		let self = this;
		return html` <div style="display: flex; flex-direction: row">
			<div style="align-self: center; margin: 0.5em">
				<button
					class="w3-button w3-theme-d1"
					title="Remove ${mention.name} mention"
					@click=${() => self.remove_mention(mention.link)}
				>
					🚮
				</button>
			</div>
			<div style="display: flex; flex-direction: column">
				<h3>${mention.name}</h3>
				<div style="padding-left: 1em">
					${Object.entries(mention)
						.filter((x) => x[0] != 'name')
						.map(
							(x) =>
								html`<div>
									<span style="font-weight: bold">${x[0]}</span>: ${x[1]}
								</div>`
						)}
				</div>
			</div>
		</div>`;
	}

	render_attach_app() {
		let self = this;

		async function attach_selected_app() {
			let name = self.renderRoot.getElementById('select').value;
			let id = self.apps[name];
			let mentions = {};
			mentions[id] = {
				name: name,
				link: id,
				type: 'application/tildefriends',
			};
			if (name && id) {
				let app = JSON.parse(await tfrpc.rpc.get_blob(id));
				for (let entry of Object.entries(app.files)) {
					mentions[entry[1]] = {
						name: entry[0],
						link: entry[1],
					};
				}
			}
			let draft = self.get_draft();
			draft.mentions = Object.assign(draft.mentions || {}, mentions);
			self.requestUpdate();
			self.notify(draft);
			self.apps = null;
		}

		if (this.apps) {
			return html`
				<div class="w3-card-4 w3-margin w3-padding">
					<select id="select" class="w3-select w3-theme-d1">
						${Object.keys(self.apps).map(
							(app) => html`<option value=${app}>${app}</option>`
						)}
					</select>
					<button class="w3-button w3-theme-d1" @click=${attach_selected_app}>
						Attach
					</button>
					<button
						class="w3-button w3-theme-d1"
						@click=${() => (this.apps = null)}
					>
						Cancel
					</button>
				</div>
			`;
		}
	}

	render_attach_app_button() {
		let self = this;
		async function attach_app() {
			self.apps = await tfrpc.rpc.apps();
		}
		if (!this.apps) {
			return html`<button class="w3-button w3-theme-d1" @click=${attach_app}>
				Attach App
			</button>`;
		} else {
			return html`<button
				class="w3-button w3-theme-d1"
				@click=${() => (this.apps = null)}
			>
				Discard App
			</button>`;
		}
	}

	set_content_warning(value) {
		let draft = this.get_draft();
		draft.content_warning = value;
		this.notify(draft);
		this.requestUpdate();
	}

	render_content_warning() {
		let self = this;
		let draft = this.get_draft();
		if (draft.content_warning !== undefined) {
			return html`
				<div class="w3-container w3-padding">
					<p>
						<input type="checkbox" class="w3-check w3-theme-d1" id="cw" @change=${() => self.set_content_warning(undefined)} checked="checked"></input>
						<label for="cw">CW</label>
					</p>
					<input type="text" class="w3-input w3-border w3-theme-d1" id="content_warning" placeholder="Enter a content warning here." @input=${self.input} value=${draft.content_warning}></input>
				</div>
			`;
		} else {
			return html`
				<input type="checkbox" class="w3-check w3-theme-d1" id="cw" @change=${() => self.set_content_warning('')}></input>
				<label for="cw">CW</label>
			`;
		}
	}

	get_draft() {
		return this.drafts[this.branch || ''] || {};
	}

	update_encrypt(event) {
		let input = event.srcElement;
		let matches = input.value.match(/@.*?\.ed25519/g);
		if (matches) {
			let draft = this.get_draft();
			let to = [...new Set(matches.concat(draft.encrypt_to))];
			this.set_encrypt(to);
			input.value = '';
		}
	}

	render_encrypt() {
		let draft = this.get_draft();
		if (draft.encrypt_to === undefined) {
			return;
		}
		return html`
			<div style="display: flex; flex-direction: row; width: 100%">
				<label for="encrypt_to">🔐 To:</label>
				<input type="text" id="encrypt_to" style="display: flex; flex: 1 1" @input=${this.update_encrypt}></input>
				<button class="w3-button w3-theme-d1" @click=${() => this.set_encrypt(undefined)}>🚮</button>
			</div>
			<ul>
				${draft.encrypt_to.map(
					(x) => html`
					<li>
						<tf-user id=${x} .users=${this.users}></tf-user>
						<input type="button" class="w3-button w3-theme-d1" value="🚮" @click=${() => this.set_encrypt(draft.encrypt_to.filter((id) => id != x))}></input>
					</li>`
				)}
			</ul>
		`;
	}

	set_encrypt(encrypt) {
		let draft = this.get_draft();
		draft.encrypt_to = encrypt;
		this.notify(draft);
		this.requestUpdate();
	}

	render() {
		let self = this;
		let draft = self.get_draft();
		let content_warning =
			draft.content_warning !== undefined
				? html`<div class="w3-panel w3-round-xlarge w3-theme-d2">
						<p id="content_warning_preview">${draft.content_warning}</p>
					</div>`
				: undefined;
		let encrypt =
			draft.encrypt_to !== undefined
				? undefined
				: html`<button
						class="w3-button w3-theme-d1"
						@click=${() => this.set_encrypt([])}
					>
						🔐
					</button>`;
		let result = html`
			<div
				class="w3-card-4 w3-theme-d4 w3-padding-small"
				style="box-sizing: border-box"
			>
				${this.channel !== undefined ?
					html`<p>To #${this.channel}:</p>` :
					undefined}
				${this.render_encrypt()}
				<div class="w3-container w3-padding-small">
					<div class="w3-half">
						<span
							class="w3-input w3-theme-d1 w3-border"
							style="resize: vertical; width: 100%; overflow: hidden; white-space: pre-wrap"
							placeholder="Write a post here."
							id="edit"
							@input=${this.input}
							@paste=${this.paste}
							contenteditable="plaintext-only"
							.innerText=${live(draft.text ?? '')}
						></span>
					</div>
					<div class="w3-half w3-padding">
						${content_warning}
						<div id="preview"></div>
					</div>
				</div>
				${Object.values(draft.mentions || {}).map((x) =>
					self.render_mention(x)
				)}
				${this.render_attach_app()} ${this.render_content_warning()}
				<button class="w3-button w3-theme-d1" id="submit" @click=${this.submit}>
					Submit
				</button>
				<button class="w3-button w3-theme-d1" @click=${this.attach}>
					Attach
				</button>
				${this.render_attach_app_button()} ${encrypt}
				<button class="w3-button w3-theme-d1" @click=${this.discard}>
					Discard
				</button>
			</div>
		`;
		return result;
	}
}

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