<script lang="ts">
	import { toast } from 'svelte-sonner';
	import { goto } from '$app/navigation';
	import {
		user,
		chats,
		settings,
		showSettings,
		chatId,
		tags,
		showSidebar,
		mobile,
		showArchivedChats,
		pinnedChats,
		scrollPaginationEnabled,
		currentChatPage
	} from '$lib/stores';
	import { onMount, getContext, tick } from 'svelte';

	const i18n = getContext('i18n');

	import { updateUserSettings } from '$lib/apis/users';
	import {
		deleteChatById,
		getChatList,
		getChatById,
		getChatListByTagName,
		updateChatById,
		getAllChatTags,
		archiveChatById,
		cloneChatById
	} from '$lib/apis/chats';
	import { WEBUI_BASE_URL } from '$lib/constants';

	import ArchivedChatsModal from './Sidebar/ArchivedChatsModal.svelte';
	import UserMenu from './Sidebar/UserMenu.svelte';
	import ChatItem from './Sidebar/ChatItem.svelte';
	import DeleteConfirmDialog from '$lib/components/common/ConfirmDialog.svelte';
	import Spinner from '../common/Spinner.svelte';
	import Loader from '../common/Loader.svelte';

	const BREAKPOINT = 768;

	let navElement;
	let search = '';

	let shiftKey = false;

	let selectedChatId = null;
	let deleteChat = null;

	let showDeleteConfirm = false;
	let showDropdown = false;

	let filteredChatList = [];

	// Pagination variables
	let chatListLoading = false;
	let allChatsLoaded = false;

	$: filteredChatList = $chats.filter((chat) => {
		if (search === '') {
			return true;
		} else {
			let title = chat.title.toLowerCase();
			const query = search.toLowerCase();

			let contentMatches = false;
			// Access the messages within chat.chat.messages
			if (chat.chat && chat.chat.messages && Array.isArray(chat.chat.messages)) {
				contentMatches = chat.chat.messages.some((message) => {
					// Check if message.content exists and includes the search query
					return message.content && message.content.toLowerCase().includes(query);
				});
			}

			return title.includes(query) || contentMatches;
		}
	});

	const enablePagination = async () => {
		// Reset pagination variables
		currentChatPage.set(1);
		allChatsLoaded = false;
		await chats.set(await getChatList(localStorage.token, $currentChatPage));

		// Enable pagination
		scrollPaginationEnabled.set(true);
	};

	const loadMoreChats = async () => {
		chatListLoading = true;

		currentChatPage.set($currentChatPage + 1);
		const newChatList = await getChatList(localStorage.token, $currentChatPage);

		// once the bottom of the list has been reached (no results) there is no need to continue querying
		allChatsLoaded = newChatList.length === 0;
		await chats.set([...$chats, ...newChatList]);

		chatListLoading = false;
	};

	onMount(async () => {
		mobile.subscribe((e) => {
			if ($showSidebar && e) {
				showSidebar.set(false);
			}

			if (!$showSidebar && !e) {
				showSidebar.set(true);
			}
		});

		showSidebar.set(window.innerWidth > BREAKPOINT);
		await pinnedChats.set(await getChatListByTagName(localStorage.token, 'pinned'));
		await enablePagination();

		let touchstart;
		let touchend;

		function checkDirection() {
			const screenWidth = window.innerWidth;
			const swipeDistance = Math.abs(touchend.screenX - touchstart.screenX);
			if (touchstart.clientX < 40 && swipeDistance >= screenWidth / 8) {
				if (touchend.screenX < touchstart.screenX) {
					showSidebar.set(false);
				}
				if (touchend.screenX > touchstart.screenX) {
					showSidebar.set(true);
				}
			}
		}

		const onTouchStart = (e) => {
			touchstart = e.changedTouches[0];
			console.log(touchstart.clientX);
		};

		const onTouchEnd = (e) => {
			touchend = e.changedTouches[0];
			checkDirection();
		};

		const onKeyDown = (e) => {
			if (e.key === 'Shift') {
				shiftKey = true;
			}
		};

		const onKeyUp = (e) => {
			if (e.key === 'Shift') {
				shiftKey = false;
			}
		};

		const onFocus = () => {};

		const onBlur = () => {
			shiftKey = false;
			selectedChatId = null;
		};

		window.addEventListener('keydown', onKeyDown);
		window.addEventListener('keyup', onKeyUp);

		window.addEventListener('touchstart', onTouchStart);
		window.addEventListener('touchend', onTouchEnd);

		window.addEventListener('focus', onFocus);
		window.addEventListener('blur', onBlur);

		return () => {
			window.removeEventListener('keydown', onKeyDown);
			window.removeEventListener('keyup', onKeyUp);

			window.removeEventListener('touchstart', onTouchStart);
			window.removeEventListener('touchend', onTouchEnd);

			window.removeEventListener('focus', onFocus);
			window.removeEventListener('blur', onBlur);
		};
	});

	// Helper function to fetch and add chat content to each chat
	const enrichChatsWithContent = async (chatList) => {
		const enrichedChats = await Promise.all(
			chatList.map(async (chat) => {
				const chatDetails = await getChatById(localStorage.token, chat.id).catch((error) => null); // Handle error or non-existent chat gracefully
				if (chatDetails) {
					chat.chat = chatDetails.chat; // Assuming chatDetails.chat contains the chat content
				}
				return chat;
			})
		);

		await chats.set(enrichedChats);
	};

	const saveSettings = async (updated) => {
		await settings.set({ ...$settings, ...updated });
		await updateUserSettings(localStorage.token, { ui: $settings });
		location.href = '/';
	};

	const deleteChatHandler = async (id) => {
		const res = await deleteChatById(localStorage.token, id).catch((error) => {
			toast.error(error);
			return null;
		});

		if (res) {
			if ($chatId === id) {
				await chatId.set('');
				await tick();
				goto('/');
			}

			allChatsLoaded = false;
			currentChatPage.set(1);
			await chats.set(await getChatList(localStorage.token, $currentChatPage));

			await pinnedChats.set(await getChatListByTagName(localStorage.token, 'pinned'));
		}
	};
</script>

<ArchivedChatsModal
	bind:show={$showArchivedChats}
	on:change={async () => {
		await chats.set(await getChatList(localStorage.token));
	}}
/>

<DeleteConfirmDialog
	bind:show={showDeleteConfirm}
	title={$i18n.t('Delete chat?')}
	on:confirm={() => {
		deleteChatHandler(deleteChat.id);
	}}
>
	<div class=" text-sm text-gray-500">
		{$i18n.t('This will delete')} <span class="  font-semibold">{deleteChat.title}</span>.
	</div>
</DeleteConfirmDialog>

<!-- svelte-ignore a11y-no-static-element-interactions -->

{#if $showSidebar}
	<div
		class=" fixed md:hidden z-40 top-0 right-0 left-0 bottom-0 bg-black/60 w-full min-h-screen h-screen flex justify-center overflow-hidden overscroll-contain"
		on:mousedown={() => {
			showSidebar.set(!$showSidebar);
		}}
	/>
{/if}

<div
	bind:this={navElement}
	id="sidebar"
	class="h-screen max-h-[100dvh] min-h-screen select-none {$showSidebar
		? 'md:relative w-[260px]'
		: '-translate-x-[260px] w-[0px]'} bg-gray-50 text-gray-900 dark:bg-gray-950 dark:text-gray-200 text-sm transition fixed z-50 top-0 left-0 rounded-r-2xl
        "
	data-state={$showSidebar}
>
	<div
		class="py-2.5 my-auto flex flex-col justify-between h-screen max-h-[100dvh] w-[260px] z-50 {$showSidebar
			? ''
			: 'invisible'}"
	>
		<div class="px-2.5 flex justify-between space-x-1 text-gray-600 dark:text-gray-400">
			<a
				id="sidebar-new-chat-button"
				class="flex flex-1 justify-between rounded-xl px-2 py-2 hover:bg-gray-100 dark:hover:bg-gray-900 transition"
				href="/"
				draggable="false"
				on:click={async () => {
					selectedChatId = null;
					await goto('/');
					const newChatButton = document.getElementById('new-chat-button');
					setTimeout(() => {
						newChatButton?.click();
						if ($mobile) {
							showSidebar.set(false);
						}
					}, 0);
				}}
			>
				<div class="self-center mx-1.5">
					<img
						crossorigin="anonymous"
						src="{WEBUI_BASE_URL}/static/favicon.png"
						class=" size-6 -translate-x-1.5 rounded-full"
						alt="logo"
					/>
				</div>
				<div class=" self-center font-medium text-sm text-gray-850 dark:text-white font-primary">
					{$i18n.t('New Chat')}
				</div>
				<div class="self-center ml-auto">
					<svg
						xmlns="http://www.w3.org/2000/svg"
						viewBox="0 0 20 20"
						fill="currentColor"
						class="size-5"
					>
						<path
							d="M5.433 13.917l1.262-3.155A4 4 0 017.58 9.42l6.92-6.918a2.121 2.121 0 013 3l-6.92 6.918c-.383.383-.84.685-1.343.886l-3.154 1.262a.5.5 0 01-.65-.65z"
						/>
						<path
							d="M3.5 5.75c0-.69.56-1.25 1.25-1.25H10A.75.75 0 0010 3H4.75A2.75 2.75 0 002 5.75v9.5A2.75 2.75 0 004.75 18h9.5A2.75 2.75 0 0017 15.25V10a.75.75 0 00-1.5 0v5.25c0 .69-.56 1.25-1.25 1.25h-9.5c-.69 0-1.25-.56-1.25-1.25v-9.5z"
						/>
					</svg>
				</div>
			</a>

			<button
				class=" cursor-pointer px-2 py-2 flex rounded-xl hover:bg-gray-100 dark:hover:bg-gray-900 transition"
				on:click={() => {
					showSidebar.set(!$showSidebar);
				}}
			>
				<div class=" m-auto self-center">
					<svg
						xmlns="http://www.w3.org/2000/svg"
						fill="none"
						viewBox="0 0 24 24"
						stroke-width="2"
						stroke="currentColor"
						class="size-5"
					>
						<path
							stroke-linecap="round"
							stroke-linejoin="round"
							d="M3.75 6.75h16.5M3.75 12h16.5m-16.5 5.25H12"
						/>
					</svg>
				</div>
			</button>
		</div>

		{#if $user?.role === 'admin'}
			<div class="px-2.5 flex justify-center text-gray-800 dark:text-gray-200">
				<a
					class="flex-grow flex space-x-3 rounded-xl px-2.5 py-2 hover:bg-gray-100 dark:hover:bg-gray-900 transition"
					href="/workspace"
					on:click={() => {
						selectedChatId = null;
						chatId.set('');

						if ($mobile) {
							showSidebar.set(false);
						}
					}}
					draggable="false"
				>
					<div class="self-center">
						<svg
							xmlns="http://www.w3.org/2000/svg"
							fill="none"
							viewBox="0 0 24 24"
							stroke-width="2"
							stroke="currentColor"
							class="size-[1.1rem]"
						>
							<path
								stroke-linecap="round"
								stroke-linejoin="round"
								d="M13.5 16.875h3.375m0 0h3.375m-3.375 0V13.5m0 3.375v3.375M6 10.5h2.25a2.25 2.25 0 0 0 2.25-2.25V6a2.25 2.25 0 0 0-2.25-2.25H6A2.25 2.25 0 0 0 3.75 6v2.25A2.25 2.25 0 0 0 6 10.5Zm0 9.75h2.25A2.25 2.25 0 0 0 10.5 18v-2.25a2.25 2.25 0 0 0-2.25-2.25H6a2.25 2.25 0 0 0-2.25 2.25V18A2.25 2.25 0 0 0 6 20.25Zm9.75-9.75H18a2.25 2.25 0 0 0 2.25-2.25V6A2.25 2.25 0 0 0 18 3.75h-2.25A2.25 2.25 0 0 0 13.5 6v2.25a2.25 2.25 0 0 0 2.25 2.25Z"
							/>
						</svg>
					</div>

					<div class="flex self-center">
						<div class=" self-center font-medium text-sm font-primary">{$i18n.t('Workspace')}</div>
					</div>
				</a>
			</div>
		{/if}

		<div class="relative flex flex-col flex-1 overflow-y-auto">
			{#if !($settings.saveChatHistory ?? true)}
				<div class="absolute z-40 w-full h-full bg-gray-50/90 dark:bg-black/90 flex justify-center">
					<div class=" text-left px-5 py-2">
						<div class=" font-medium">{$i18n.t('Chat History is off for this browser.')}</div>
						<div class="text-xs mt-2">
							{$i18n.t(
								"When history is turned off, new chats on this browser won't appear in your history on any of your devices."
							)}
							<span class=" font-semibold"
								>{$i18n.t('This setting does not sync across browsers or devices.')}</span
							>
						</div>

						<div class="mt-3">
							<button
								class="flex justify-center items-center space-x-1.5 px-3 py-2.5 rounded-lg text-xs bg-gray-100 hover:bg-gray-200 transition text-gray-800 font-medium w-full"
								type="button"
								on:click={() => {
									saveSettings({
										saveChatHistory: true
									});
								}}
							>
								<svg
									xmlns="http://www.w3.org/2000/svg"
									viewBox="0 0 16 16"
									fill="currentColor"
									class="w-3 h-3"
								>
									<path
										fill-rule="evenodd"
										d="M8 1a.75.75 0 0 1 .75.75v6.5a.75.75 0 0 1-1.5 0v-6.5A.75.75 0 0 1 8 1ZM4.11 3.05a.75.75 0 0 1 0 1.06 5.5 5.5 0 1 0 7.78 0 .75.75 0 0 1 1.06-1.06 7 7 0 1 1-9.9 0 .75.75 0 0 1 1.06 0Z"
										clip-rule="evenodd"
									/>
								</svg>

								<div>{$i18n.t('Enable Chat History')}</div>
							</button>
						</div>
					</div>
				</div>
			{/if}

			<div class="px-2 mt-0.5 mb-2 flex justify-center space-x-2">
				<div class="flex w-full rounded-xl" id="chat-search">
					<div class="self-center pl-3 py-2 rounded-l-xl bg-transparent">
						<svg
							xmlns="http://www.w3.org/2000/svg"
							viewBox="0 0 20 20"
							fill="currentColor"
							class="w-4 h-4"
						>
							<path
								fill-rule="evenodd"
								d="M9 3.5a5.5 5.5 0 100 11 5.5 5.5 0 000-11zM2 9a7 7 0 1112.452 4.391l3.328 3.329a.75.75 0 11-1.06 1.06l-3.329-3.328A7 7 0 012 9z"
								clip-rule="evenodd"
							/>
						</svg>
					</div>

					<input
						class="w-full rounded-r-xl py-1.5 pl-2.5 pr-4 text-sm bg-transparent dark:text-gray-300 outline-none"
						placeholder={$i18n.t('Search')}
						bind:value={search}
						on:focus={async () => {
							// TODO: migrate backend for more scalable search mechanism
							scrollPaginationEnabled.set(false);
							await chats.set(await getChatList(localStorage.token)); // when searching, load all chats
							enrichChatsWithContent($chats);
						}}
					/>
				</div>
			</div>

			{#if $tags.filter((t) => t.name !== 'pinned').length > 0}
				<div class="px-2.5 mb-2 flex gap-1 flex-wrap">
					<button
						class="px-2.5 text-xs font-medium bg-gray-50 dark:bg-gray-900 dark:hover:bg-gray-800 transition rounded-full"
						on:click={async () => {
							await enablePagination();
						}}
					>
						{$i18n.t('all')}
					</button>
					{#each $tags.filter((t) => t.name !== 'pinned') as tag}
						<button
							class="px-2.5 text-xs font-medium bg-gray-50 dark:bg-gray-900 dark:hover:bg-gray-800 transition rounded-full"
							on:click={async () => {
								scrollPaginationEnabled.set(false);
								let chatIds = await getChatListByTagName(localStorage.token, tag.name);
								if (chatIds.length === 0) {
									await tags.set(await getAllChatTags(localStorage.token));

									// if the tag we deleted is no longer a valid tag, return to main chat list view
									await enablePagination();
								}
								await chats.set(chatIds);

								chatListLoading = false;
							}}
						>
							{tag.name}
						</button>
					{/each}
				</div>
			{/if}

			{#if $pinnedChats.length > 0}
				<div class="pl-2 py-2 flex flex-col space-y-1">
					<div class="">
						<div class="w-full pl-2.5 text-xs text-gray-500 dark:text-gray-500 font-medium pb-1.5">
							{$i18n.t('Pinned')}
						</div>

						{#each $pinnedChats as chat, idx}
							<ChatItem
								{chat}
								{shiftKey}
								selected={selectedChatId === chat.id}
								on:select={() => {
									selectedChatId = chat.id;
								}}
								on:unselect={() => {
									selectedChatId = null;
								}}
								on:delete={(e) => {
									if ((e?.detail ?? '') === 'shift') {
										deleteChatHandler(chat.id);
									} else {
										deleteChat = chat;
										showDeleteConfirm = true;
									}
								}}
							/>
						{/each}
					</div>
				</div>
			{/if}

			<div class="pl-2 my-2 flex-1 flex flex-col space-y-1 overflow-y-auto scrollbar-hidden">
				{#each filteredChatList as chat, idx}
					{#if idx === 0 || (idx > 0 && chat.time_range !== filteredChatList[idx - 1].time_range)}
						<div
							class="w-full pl-2.5 text-xs text-gray-500 dark:text-gray-500 font-medium {idx === 0
								? ''
								: 'pt-5'} pb-0.5"
						>
							{$i18n.t(chat.time_range)}
							<!-- localisation keys for time_range to be recognized from the i18next parser (so they don't get automatically removed):
							{$i18n.t('Today')}
							{$i18n.t('Yesterday')}
							{$i18n.t('Previous 7 days')}
							{$i18n.t('Previous 30 days')}
							{$i18n.t('January')}
							{$i18n.t('February')}
							{$i18n.t('March')}
							{$i18n.t('April')}
							{$i18n.t('May')}
							{$i18n.t('June')}
							{$i18n.t('July')}
							{$i18n.t('August')}
							{$i18n.t('September')}
							{$i18n.t('October')}
							{$i18n.t('November')}
							{$i18n.t('December')}
							-->
						</div>
					{/if}

					<ChatItem
						{chat}
						{shiftKey}
						selected={selectedChatId === chat.id}
						on:select={() => {
							selectedChatId = chat.id;
						}}
						on:unselect={() => {
							selectedChatId = null;
						}}
						on:delete={(e) => {
							if ((e?.detail ?? '') === 'shift') {
								deleteChatHandler(chat.id);
							} else {
								deleteChat = chat;
								showDeleteConfirm = true;
							}
						}}
					/>
				{/each}

				{#if $scrollPaginationEnabled && !allChatsLoaded}
					<Loader
						on:visible={(e) => {
							if (!chatListLoading) {
								loadMoreChats();
							}
						}}
					>
						<div class="w-full flex justify-center py-1 text-xs animate-pulse items-center gap-2">
							<Spinner className=" size-4" />
							<div class=" ">Loading...</div>
						</div>
					</Loader>
				{/if}
			</div>
		</div>

		<div class="px-2.5">
			<!-- <hr class=" border-gray-900 mb-1 w-full" /> -->

			<div class="flex flex-col font-primary">
				{#if $user !== undefined}
					<UserMenu
						role={$user.role}
						on:show={(e) => {
							if (e.detail === 'archived-chat') {
								showArchivedChats.set(true);
							}
						}}
					>
						<button
							class=" flex rounded-xl py-3 px-3.5 w-full hover:bg-gray-100 dark:hover:bg-gray-900 transition"
							on:click={() => {
								showDropdown = !showDropdown;
							}}
						>
							<div class=" self-center mr-3">
								<img
									src={$user.profile_image_url}
									class=" max-w-[30px] object-cover rounded-full"
									alt="User profile"
								/>
							</div>
							<div class=" self-center font-medium">{$user.name}</div>
						</button>
					</UserMenu>
				{/if}
			</div>
		</div>
	</div>
</div>

<style>
	.scrollbar-hidden:active::-webkit-scrollbar-thumb,
	.scrollbar-hidden:focus::-webkit-scrollbar-thumb,
	.scrollbar-hidden:hover::-webkit-scrollbar-thumb {
		visibility: visible;
	}
	.scrollbar-hidden::-webkit-scrollbar-thumb {
		visibility: hidden;
	}
</style>
