<template>
  <div class="max-w-4xl mx-auto px-4 sm:px-6 lg:px-8 py-8">
    <!-- Header -->
    <div class="flex flex-col sm:flex-row justify-between items-start sm:items-center mb-6 sm:mb-8 space-y-4 sm:space-y-0">
      <div>
        <h1 class="text-2xl sm:text-3xl font-bold text-gray-900">Publications</h1>
        <p class="text-sm sm:text-base text-gray-600 mt-1">Partagez vos moments avec le groupe</p>
      </div>
      <button
        @click="showCreateModal = true"
        class="w-full sm:w-auto btn-primary justify-center"
      >
        <Plus class="w-4 h-4 mr-2" />
        Nouvelle publication
      </button>
    </div>

    <!-- Create Post Form -->
    <div class="card p-4 sm:p-6 mb-8">
      <div class="flex items-start space-x-3">
        <img
          v-if="user?.avatar_url"
          :src="getMediaUrl(user.avatar_url)"
          :alt="user?.full_name"
          class="w-10 h-10 rounded-full object-cover"
        >
        <div v-else class="w-10 h-10 rounded-full bg-primary-100 flex items-center justify-center">
          <User class="w-5 h-5 text-primary-600" />
        </div>
        
        <div class="flex-1">
          <MentionInput
            v-model="newPost.content"
            :users="users"
            :rows="3"
            placeholder="Quoi de neuf ? Mentionnez des amis avec @..."
            @mentions-changed="handleMentionsChanged"
          />
          

          
          <div class="flex items-center justify-between mt-3">
            <div class="flex items-center space-x-2">
              <button
                @click="showImageUpload = !showImageUpload"
                class="text-gray-500 hover:text-primary-600 transition-colors"
                title="Ajouter une image"
              >
                <Image class="w-5 h-5" />
              </button>
              <span class="text-xs text-gray-500">{{ newPost.content.length }}/5000</span>
            </div>
            
            <button
              @click="createPost"
              :disabled="!newPost.content.trim() || creating"
              class="btn-primary"
            >
              {{ creating ? 'Publication...' : 'Publier' }}
            </button>
          </div>
          
          <!-- Image upload -->
          <div v-if="showImageUpload" class="mt-3">
            <input
              ref="imageInput"
              type="file"
              accept="image/*"
              class="hidden"
              @change="handleImageChange"
            >
            <button
              @click="$refs.imageInput.click()"
              class="btn-secondary text-sm"
            >
              <Upload class="w-4 h-4 mr-2" />
              Sélectionner une image
            </button>
            <div v-if="newPost.image_url" class="mt-2 relative inline-block">
              <img
                :src="getMediaUrl(newPost.image_url)"
                :alt="newPost.content"
                class="max-w-xs max-h-32 rounded-lg object-cover"
              >
              <button
                @click="removeImage"
                class="absolute top-1 right-1 bg-red-500 text-white rounded-full w-6 h-6 flex items-center justify-center hover:bg-red-600"
              >
                <X class="w-4 h-4" />
              </button>
            </div>
          </div>
        </div>
      </div>
    </div>

    <!-- Posts List -->
    <div class="space-y-6">
      <div
        v-for="post in posts"
        :key="post.id"
        class="card p-4 sm:p-6"
      >
        <!-- Post Header -->
        <div class="flex items-start space-x-3 mb-4">
          <img
            v-if="post.author_avatar"
            :src="getMediaUrl(post.author_avatar)"
            :alt="post.author_name"
            class="w-10 h-10 rounded-full object-cover"
          >
          <div v-else class="w-10 h-10 rounded-full bg-primary-100 flex items-center justify-center">
            <User class="w-5 h-5 text-primary-600" />
          </div>
          
          <div class="flex-1">
            <div class="flex items-center space-x-2">
              <router-link 
                :to="`/profile/${post.author_id}`"
                class="font-medium text-gray-900 hover:text-primary-600 transition-colors"
              >
                {{ post.author_name }}
              </router-link>
              <span class="text-sm text-gray-500">{{ formatRelativeDate(post.created_at) }}</span>
            </div>
            
            <!-- Mentions -->
            <div v-if="post.mentioned_users && post.mentioned_users.length > 0" class="mt-1">
              <span class="text-xs text-gray-500">Mentionne : </span>
              <span
                v-for="mentionedUser in post.mentioned_users"
                :key="mentionedUser.id"
                class="text-xs text-primary-600 hover:underline cursor-pointer"
              >
                @{{ mentionedUser.username }}
              </span>
            </div>
          </div>
          
          <!-- Delete button for author or admin -->
          <button
            v-if="canDeletePost(post)"
            @click="deletePost(post.id)"
            class="text-gray-400 hover:text-red-600 transition-colors"
            title="Supprimer"
          >
            <Trash2 class="w-4 h-4" />
          </button>
        </div>
        
        <!-- Post Content -->
        <div class="mb-4">
          <Mentions :content="post.content" :mentions="post.mentioned_users" />
          
          <!-- Post Image -->
          <img
            v-if="post.image_url"
            :src="getMediaUrl(post.image_url)"
            :alt="post.content"
            class="mt-3 rounded-lg max-w-full max-h-96 object-cover"
          >
        </div>
        
        <!-- Post Actions -->
        <div class="flex items-center space-x-6 text-sm text-gray-500">
          <button
            @click="togglePostLike(post)"
            class="flex items-center space-x-2 hover:text-primary-600 transition-colors"
            :class="{ 'text-primary-600': post.is_liked }"
          >
            <Heart :class="post.is_liked ? 'fill-current' : ''" class="w-4 h-4" />
            <span>{{ post.likes_count || 0 }}</span>
          </button>
          
          <button
            @click="toggleComments(post.id)"
            class="flex items-center space-x-2 hover:text-primary-600 transition-colors"
          >
            <MessageCircle class="w-4 h-4" />
            <span>{{ post.comments_count || 0 }}</span>
          </button>
        </div>
        
        <!-- Comments Section -->
        <div v-if="post.showComments" class="mt-4 pt-4 border-t border-gray-100">
          <!-- Add Comment -->
          <div class="flex items-start space-x-3 mb-4">
            <img
              v-if="user?.avatar_url"
              :src="getMediaUrl(user.avatar_url)"
              :alt="user?.full_name"
              class="w-8 h-8 rounded-full object-cover"
            >
            <div v-else class="w-8 h-8 rounded-full bg-primary-100 flex items-center justify-center">
              <User class="w-4 h-4 text-primary-600" />
            </div>
            
            <div class="flex-1">
              <MentionInput
                v-model="post.newComment"
                :users="users"
                :rows="2"
                placeholder="Ajouter un commentaire... (utilisez @username pour mentionner)"
                @mentions-changed="(mentions) => handleCommentMentionsChanged(post.id, mentions)"
              />
              <div class="flex items-center justify-between mt-2">
                <span class="text-xs text-gray-500">{{ (post.newComment || '').length }}/500</span>
                <button
                  @click="addComment(post)"
                  :disabled="!post.newComment?.trim()"
                  class="btn-primary text-sm px-3 py-1"
                >
                  Commenter
                </button>
              </div>
            </div>
          </div>
          
          <!-- Comments List -->
          <div v-if="post.comments && post.comments.length > 0" class="space-y-3">
            <div
              v-for="comment in post.comments"
              :key="comment.id"
              class="flex items-start space-x-3 p-3 bg-gray-50 rounded-lg"
            >
              <img
                v-if="comment.author_avatar"
                :src="getMediaUrl(comment.author_avatar)"
                :alt="comment.author_name"
                class="w-6 h-6 rounded-full object-cover"
              >
              <div v-else class="w-6 h-6 rounded-full bg-gray-200 flex items-center justify-center">
                <User class="w-3 h-3 text-gray-500" />
              </div>
              
              <div class="flex-1">
                <div class="flex items-center space-x-2">
                  <router-link 
                    :to="`/profile/${comment.author_id}`"
                    class="font-medium text-sm text-gray-900 hover:text-primary-600 transition-colors"
                  >
                    {{ comment.author_name }}
                  </router-link>
                  <span class="text-xs text-gray-500">{{ formatRelativeDate(comment.created_at) }}</span>
                </div>
                <Mentions :content="comment.content" :mentions="comment.mentioned_users || []" class="text-sm text-gray-700 mt-1" />
              </div>
              
              <!-- Delete comment button -->
              <button
                v-if="canDeleteComment(comment)"
                @click="deleteComment(post.id, comment.id)"
                class="text-gray-400 hover:text-red-600 transition-colors"
                title="Supprimer"
              >
                <X class="w-3 h-3" />
              </button>
            </div>
          </div>
        </div>
      </div>
    </div>

    <!-- Load more -->
    <div v-if="hasMorePosts" class="text-center mt-8">
      <button
        @click="loadMorePosts"
        :disabled="loading"
        class="btn-secondary"
      >
        {{ loading ? 'Chargement...' : 'Charger plus' }}
      </button>
    </div>
    
    <!-- Empty state -->
    <div v-if="posts.length === 0 && !loading" class="text-center py-12">
      <MessageSquare class="w-16 h-16 text-gray-300 mx-auto mb-4" />
      <h3 class="text-lg font-medium text-gray-900 mb-2">Aucune publication</h3>
      <p class="text-gray-600">Soyez le premier à partager quelque chose !</p>
    </div>
  </div>
</template>

<script setup>
import { ref, computed, onMounted } from 'vue'
import { useAuthStore } from '@/stores/auth'
import { useToast } from 'vue-toastification'
import axios from '@/utils/axios'
import { getMediaUrl } from '@/utils/axios'
import { formatDistanceToNow } from 'date-fns'
import { fr } from 'date-fns/locale'
import {
  Plus,
  User,
  Image,
  Upload,
  X,
  Heart,
  MessageCircle,
  Trash2,
  MessageSquare
} from 'lucide-vue-next'
import Mentions from '@/components/Mentions.vue'
import MentionInput from '@/components/MentionInput.vue'

const authStore = useAuthStore()
const toast = useToast()

const user = computed(() => authStore.user)
const posts = ref([])
const users = ref([])
const loading = ref(false)
const creating = ref(false)
const showCreateModal = ref(false)
const showImageUpload = ref(false)

const offset = ref(0)
const hasMorePosts = ref(true)

const newPost = ref({
  content: '',
  image_url: '',
  mentioned_user_ids: []
})

function formatRelativeDate(date) {
  return formatDistanceToNow(new Date(date), { addSuffix: true, locale: fr })
}

function handleMentionsChanged(mentions) {
  newPost.value.mentioned_user_ids = mentions.map(m => m.id)
}

function handleCommentMentionsChanged(postId, mentions) {
  const post = posts.value.find(p => p.id === postId)
  if (post) {
    post.commentMentions = mentions
  }
}



async function createPost() {
  if (!newPost.value.content.trim()) return
  
  creating.value = true
  try {
    const response = await axios.post('/api/posts', {
      content: newPost.value.content,
      image_url: newPost.value.image_url,
      mentioned_user_ids: newPost.value.mentioned_user_ids
    })
    
    // Add new post to the beginning of the list
    posts.value.unshift(response.data)
    
    // Reset form
    newPost.value = {
      content: '',
      image_url: '',
      mentioned_user_ids: []
    }
    showImageUpload.value = false
    
    toast.success('Publication créée avec succès')
  } catch (error) {
    toast.error('Erreur lors de la création de la publication')
  }
  creating.value = false
}

async function togglePostLike(post) {
  try {
    const response = await axios.post(`/api/posts/${post.id}/like`)
    post.is_liked = response.data.is_liked
    post.likes_count = response.data.likes_count
    toast.success(post.is_liked ? 'Post liké' : 'Like retiré')
  } catch (error) {
    toast.error('Erreur lors de la mise à jour du like')
  }
}

function toggleComments(postId) {
  const post = posts.value.find(p => p.id === postId)
  if (post) {
    post.showComments = !post.showComments
    if (post.showComments && !post.comments) {
      post.comments = []
      post.newComment = ''
    }
  }
}

async function addComment(post) {
  if (!post.newComment?.trim()) return
  
  try {
    const response = await axios.post(`/api/posts/${post.id}/comment`, {
      content: post.newComment.trim()
    })
    
    // Add new comment to the post
    if (!post.comments) post.comments = []
    post.comments.push(response.data.comment)
    post.comments_count = (post.comments_count || 0) + 1
    
    // Reset comment input
    post.newComment = ''
    
    toast.success('Commentaire ajouté')
  } catch (error) {
    toast.error('Erreur lors de l\'ajout du commentaire')
  }
}

async function deleteComment(postId, commentId) {
  try {
    await axios.delete(`/api/posts/${postId}/comment/${commentId}`)
    
    const post = posts.value.find(p => p.id === postId)
    if (post && post.comments) {
      post.comments = post.comments.filter(c => c.id !== commentId)
      post.comments_count = Math.max(0, (post.comments_count || 1) - 1)
    }
    
    toast.success('Commentaire supprimé')
  } catch (error) {
    toast.error('Erreur lors de la suppression du commentaire')
  }
}

async function handleImageChange(event) {
  const file = event.target.files[0]
  if (!file) return
  
  if (!file.type.startsWith('image/')) {
    toast.error('Veuillez sélectionner une image')
    return
  }
  
  if (file.size > 5 * 1024 * 1024) {
    toast.error('L\'image est trop volumineuse (max 5MB)')
    return
  }
  
  try {
    const formData = new FormData()
    formData.append('file', file)
    
    const response = await axios.post('/api/posts/upload-image', formData, {
      headers: { 'Content-Type': 'multipart/form-data' }
    })
    
    newPost.value.image_url = response.data.image_url
  } catch (error) {
    toast.error('Erreur lors de l\'upload de l\'image')
  }
  
  event.target.value = ''
}

function removeImage() {
  newPost.value.image_url = ''
}

async function fetchPosts() {
  loading.value = true
  try {
    const response = await axios.get(`/api/posts?limit=10&offset=${offset.value}`)
    if (offset.value === 0) {
      posts.value = response.data
    } else {
      posts.value.push(...response.data)
    }
    
    hasMorePosts.value = response.data.length === 10
  } catch (error) {
    toast.error('Erreur lors du chargement des publications')
  }
  loading.value = false
}

async function fetchUsers() {
  try {
    const response = await axios.get('/api/users')
    users.value = response.data
  } catch (error) {
    console.error('Error fetching users:', error)
  }
}

async function loadMorePosts() {
  offset.value += 10
  await fetchPosts()
}

async function deletePost(postId) {
  if (!confirm('Êtes-vous sûr de vouloir supprimer cette publication ?')) return
  
  try {
    await axios.delete(`/api/posts/${postId}`)
    posts.value = posts.value.filter(p => p.id !== postId)
    toast.success('Publication supprimée')
  } catch (error) {
    toast.error('Erreur lors de la suppression')
  }
}

function canDeletePost(post) {
  return user.value && (post.author_id === user.value.id || user.value.is_admin)
}

function canDeleteComment(comment) {
  return user.value && (comment.author_id === user.value.id || user.value.is_admin)
}

onMounted(() => {
  fetchPosts()
  fetchUsers()
})
</script>
