<script lang="ts">
	import { onMount } from 'svelte';
	import { authStore, currentUser } from '$lib/auth';
	import * as Sheet from '$lib/components/ui/sheet';
	import { Button } from '$lib/components/ui/button';
	import { HelpCircle, Edit2, Save, X, ChevronLeft, Plus } from 'lucide-svelte';
	import { toast } from 'svelte-sonner';
	import { helpApi, type HelpArticle } from '$lib/api/help';
	import { helpStore } from '$lib/stores/help.svelte';

	// Nota: Estas librerías deben ser instaladas: npm install marked dompurify @types/dompurify
	// Si no están, fallará el import. El usuario debe instalarlas.
	// import { marked } from 'marked';
	// import DOMPurify from 'dompurify';

	let articles = $state<HelpArticle[]>([]);
	let selectedArticle = $state<HelpArticle | null>(null);
	let isEditing = $state(false);
	let editContent = $state('');
	let editTitle = $state('');
	let isLoading = $state(false);
	let isCreating = $state(false);

	// Temporalmente habilitado para todos los usuarios por petición
	const isAdmin = $derived(true);

	async function loadArticles() {
		isLoading = true;
		try {
			articles = await helpApi.listArticles();
		} catch (e) {
			toast.error('Error al cargar artículos de ayuda');
		} finally {
			isLoading = false;
		}
	}

	function selectArticle(article: HelpArticle) {
		selectedArticle = article;
		isEditing = false;
		isCreating = false;
	}

	function startEdit() {
		if (!selectedArticle) return;
		editContent = selectedArticle.content;
		editTitle = selectedArticle.title;
		isEditing = true;
		isCreating = false;
	}

	function startCreate() {
		editContent = '# Nuevo Artículo\nEscribe el contenido aquí...';
		editTitle = '';
		isEditing = true;
		isCreating = true;
		selectedArticle = {
			uuid: '',
			slug: '',
			title: '',
			content: '',
			updated_at: '',
			last_editor: ''
		}; // Mock for UI
	}

	function generateSlug(text: string): string {
		return text
			.toLowerCase()
			.replace(/[^\w ]+/g, '')
			.replace(/ +/g, '-');
	}

	async function saveChanges() {
		try {
			if (isCreating) {
				const slug = generateSlug(editTitle);
				const newArticle = await helpApi.createArticle({
					title: editTitle,
					content: editContent,
					slug: slug,
					last_editor: $currentUser?.username || 'unknown'
				});
				selectedArticle = newArticle;
				toast.success('Capítulo creado con éxito');
			} else if (selectedArticle) {
				const updated = await helpApi.updateArticle(selectedArticle.uuid, {
					content: editContent,
					title: editTitle,
					last_editor: $currentUser?.username || 'unknown'
				});
				selectedArticle = updated;
				toast.success('Cambios guardados y sincronizados');
			}
			isEditing = false;
			isCreating = false;
			loadArticles();
		} catch (e) {
			toast.error(isCreating ? 'Error al crear artículo' : 'Error al guardar cambios');
		}
	}

	onMount(() => {
		loadArticles();
	});

	// Simple markdown renderer fallback if marked is not available
	function renderMarkdown(content: string) {
		// En una implementación real, usar marked + DOMPurify
		// return DOMPurify.sanitize(marked.parse(content));

		// Fallback ultra-básico para demostración
		return content
			.replace(/^# (.*$)/gim, '<h1>$1</h1>')
			.replace(/^## (.*$)/gim, '<h2>$1</h2>')
			.replace(/^### (.*$)/gim, '<h3>$1</h3>')
			.replace(/\*\*(.*)\*\*/gim, '<b>$1</b>')
			.replace(/\*(.*)\*/gim, '<i>$1</i>')
			.replace(/\n/gim, '<br />');
	}
</script>

<Sheet.Root bind:open={helpStore.isOpen}>
	<Sheet.Trigger>
		{#snippet child({ props })}
			<button
				{...props}
				class="fixed right-6 bottom-6 z-50 flex h-14 w-14 items-center justify-center rounded-full bg-primary text-primary-foreground shadow-lg transition-transform hover:scale-110 active:scale-95"
				aria-label="Ayuda"
			>
				<HelpCircle size={28} />
			</button>
		{/snippet}
	</Sheet.Trigger>
	<Sheet.Content side="right" class="w-[400px] sm:w-[540px]">
		<Sheet.Header>
			<Sheet.Title class="flex items-center gap-2">
				{#if selectedArticle}
					<Button variant="ghost" size="icon" onclick={() => (selectedArticle = null)}>
						<ChevronLeft size={20} />
					</Button>
				{/if}
				Base de Conocimientos
			</Sheet.Title>
		</Sheet.Header>

		<div class="mt-6 flex h-[calc(100vh-120px)] flex-col">
			{#if !selectedArticle}
				<div class="space-y-4">
					<div class="flex items-center justify-between">
						<h3 class="text-lg font-medium">Artículos Disponibles</h3>
						{#if isAdmin}
							<Button variant="outline" size="sm" onclick={startCreate}>
								<Plus size={16} class="mr-2" /> Agregar Nuevo
							</Button>
						{/if}
					</div>
					{#if isLoading}
						<p class="py-10 text-center text-sm text-muted-foreground">Cargando...</p>
					{:else if articles.length === 0}
						<p class="py-10 text-center text-sm text-muted-foreground">
							No hay artículos de ayuda disponibles.
						</p>
					{/if}
					<div class="grid gap-2">
						{#each articles as article}
							<button
								onclick={() => selectArticle(article)}
								class="flex flex-col items-start rounded-lg border p-4 text-left transition-colors hover:bg-accent"
							>
								<span class="font-semibold">{article.title}</span>
								<span class="text-xs text-muted-foreground"
									>Última edición: {new Date(article.updated_at).toLocaleDateString()}</span
								>
							</button>
						{/each}
					</div>
				</div>
			{:else}
				<div class="flex flex-1 flex-col gap-4">
					{#if isEditing}
						<div class="space-y-4">
							<input
								bind:value={editTitle}
								class="w-full rounded-md border bg-transparent p-2 text-xl font-bold"
								placeholder="Título del artículo"
							/>
							<textarea
								bind:value={editContent}
								class="min-h-[400px] w-full flex-1 rounded-md border bg-transparent p-4 font-mono text-sm focus:ring-1 focus:ring-primary focus:outline-none"
								placeholder="Escribe en Markdown..."
							></textarea>
							<div class="flex justify-end gap-2">
								<Button
									variant="outline"
									onclick={() => {
										isEditing = false;
										if (isCreating) selectedArticle = null;
										isCreating = false;
									}}
								>
									<X size={16} class="mr-2" /> Cancelar
								</Button>
								<Button onclick={saveChanges}>
									<Save size={16} class="mr-2" /> Guardar Cambios
								</Button>
							</div>
						</div>
					{:else}
						<div class="flex flex-col gap-4">
							<div class="flex items-center justify-between">
								<h2 class="text-2xl font-bold">{selectedArticle.title}</h2>
								{#if isAdmin}
									<Button variant="outline" size="sm" onclick={startEdit}>
										<Edit2 size={16} class="mr-2" /> Editar
									</Button>
								{/if}
							</div>
							<div class="prose prose-sm max-w-none border-t pt-4 dark:prose-invert">
								{@html renderMarkdown(selectedArticle.content)}
							</div>
						</div>
					{/if}
				</div>
			{/if}
		</div>
	</Sheet.Content>
</Sheet.Root>

<style>
	/* Estilos adicionales si son necesarios */
</style>
