from django.contrib import admin
from django.utils.html import format_html
from django.utils.translation import gettext_lazy as _
from django.db.models import Count
from unfold.admin import ModelAdmin, TabularInline
from unfold.contrib.filters.admin import RangeNumericFilter, RangeDateTimeFilter

from apps.chat.models import RoomMessage, ChatMessage, MessageReadStatus
from utils.admin import project_admin_site


class ChatMessageInline(TabularInline):
    model = ChatMessage
    extra = 0
    fields = ('sender', 'content', 'content_type', 'sent_at', 'is_deleted')
    readonly_fields = ('sent_at',)
    can_delete = False
    show_change_link = True
    classes = ['collapse']
    verbose_name = _("Message")
    verbose_name_plural = _("Messages")


class MessageReadStatusAdmin(ModelAdmin):
    list_display = (
        'user', 'message', 'is_read_status', 'read_at',
    )
    list_filter = (
        ('read_at', RangeDateTimeFilter),
        'is_read',
    )
    search_fields = ('user__username', 'user__email', 'message__content')
    readonly_fields = ('read_at',)
    
    def is_read_status(self, obj):
        if obj.is_read:
            return format_html('<span class="inline-flex items-center px-2.5 py-0.5 rounded-full text-xs font-medium bg-green-100 text-green-800">Read</span>')
        return format_html('<span class="inline-flex items-center px-2.5 py-0.5 rounded-full text-xs font-medium bg-red-100 text-red-800">Unread</span>')
    
    is_read_status.short_description = _("Read Status")


class RoomMessageAdmin(ModelAdmin):
    list_display = (
        'name', 'room_type_badge', 'course', 'initiator',
         'messages_count', 'view_messages_button'
    )
    list_filter = (
        'room_type', 
        ('created_at', RangeDateTimeFilter), 
        ('updated_at', RangeDateTimeFilter), 
        'course'
    )
    search_fields = ('name', 'description', 'course__title', 'initiator__username', 'recipient__username')
    ordering = ('-created_at',)
    readonly_fields = ('created_at', 'updated_at', 'messages_count')
    inlines = [ChatMessageInline]
    
    fieldsets = (
        (_("Room Information"), {
            'fields': ('name', 'description', 'room_type', 'messages_count'),
            'classes': ('grid-col-2',),
        }),
        (_("Relations"), {
            'fields': ('course', 'initiator', 'recipient'),
            'classes': ('grid-col-2',),
        }),
        (_("Timestamps"), {
            'fields': ('created_at', 'updated_at'),
            'classes': ('grid-col-2',),
        }),
    )
    
    def messages_count(self, obj):
        count = obj.messages.count()
        return format_html('<span class="inline-flex items-center px-2.5 py-0.5 rounded-full text-xs font-medium bg-blue-100 text-blue-800">{}</span>', count)
    
    messages_count.short_description = _("Messages Count")
    
    def room_type_badge(self, obj):
        if obj.room_type == 'group':
            return format_html('<span class="inline-flex items-center px-2.5 py-0.5 rounded-full text-xs font-medium bg-purple-100 text-purple-800">Group</span>')
        return format_html('<span class="inline-flex items-center px-2.5 py-0.5 rounded-full text-xs font-medium bg-indigo-100 text-indigo-800">Private</span>')
    
    room_type_badge.short_description = _("Room Type")
    
    def get_queryset(self, request):
        queryset = super().get_queryset(request)
        queryset = queryset.annotate(
            total_messages=Count('messages')
        )
        return queryset
        
    def view_messages_button(self, obj):
        from django.urls import reverse
        url = f"{reverse('admin:chat_chatmessage_changelist')}?room__id__exact={obj.id}"
        
        return format_html(
            '<a href="{}" class="inline-flex items-center px-3 py-1.5 rounded text-xs font-medium bg-blue-500 text-white hover:bg-blue-600">'
            '<span class="material-icons-outlined mr-1" style="font-size: 14px;">chat</span> {}</a>',
            url, _("View Messages")
        )
    
    view_messages_button.short_description = _("Messages")


class MessageReadStatusInline(TabularInline):
    model = MessageReadStatus
    extra = 0
    fields = ('user', 'is_read', 'read_at')
    readonly_fields = ('read_at',)
    can_delete = False
    show_change_link = True
    classes = ['collapse']
    verbose_name = _("Read Status")
    verbose_name_plural = _("Read Statuses")


class ChatMessageAdmin(ModelAdmin):
    change_list_template = 'admin/chat/chatmessage/change_list.html'
    list_display = (
        'id', 'room', 'sender', 'content_type_badge', 'content_preview', 
        'content_size_display', 'has_attachment', 'sent_at', 'is_deleted_status'
    )
    list_filter = (
        'room',
        'content_type', 
        'is_deleted', 
        ('sent_at', RangeDateTimeFilter), 
        ('updated_at', RangeDateTimeFilter),
        ('content_size', RangeNumericFilter)
    )
    search_fields = ('room__name', 'sender__username', 'content')
    ordering = ('-sent_at',)
    readonly_fields = ('sent_at', 'updated_at', 'content_size', 'attachment_preview')
    inlines = [MessageReadStatusInline]
    
    fieldsets = (
        (_("Message Information"), {
            'fields': ('room', 'sender', 'content', 'content_type'),
            'classes': ('grid-col-2',),
        }),
        (_("Attachments"), {
            'fields': ('file_attachment', 'image_attachment', 'attachment_preview'),
            'classes': ('grid-col-2',),
        }),
        (_("Additional Info"), {
            'fields': ('content_size',),
            'classes': ('grid-col-1',),
        }),
        (_("Status"), {
            'fields': ('is_deleted', 'deleted_at'),
            'classes': ('grid-col-2',),
        }),
        (_("Timestamps"), {
            'fields': ('sent_at', 'updated_at'),
            'classes': ('grid-col-2',),
        }),
    )
    
    def content_preview(self, obj):
        if obj.content_type == 'text':
            preview = obj.content[:50] + '...' if len(obj.content) > 50 else obj.content
            return preview
        return f"{obj.content_type} content"
    
    content_preview.short_description = _("Content Preview")
    
    def content_type_badge(self, obj):
        badges = {
            'text': ('blue', 'Text'),
            'file': ('yellow', 'File'),
            'audio': ('green', 'Audio'),
            'image': ('pink', 'Image'),
        }
        color, label = badges.get(obj.content_type, ('gray', obj.content_type))
        return format_html(
            '<span class="inline-flex items-center px-2.5 py-0.5 rounded-full text-xs font-medium bg-{}-100 text-{}-800">{}</span>',
            color, color, label
        )
    
    content_type_badge.short_description = _("Type")
    
    def is_deleted_status(self, obj):
        if obj.is_deleted:
            return format_html('<span class="inline-flex items-center px-2.5 py-0.5 rounded-full text-xs font-medium bg-red-100 text-red-800">Deleted</span>')
        return format_html('<span class="inline-flex items-center px-2.5 py-0.5 rounded-full text-xs font-medium bg-green-100 text-green-800">Active</span>')
    
    is_deleted_status.short_description = _("Status")
    
    def content_size_display(self, obj):
        if obj.content_size:
            # Format size in KB if larger than 1024 bytes
            if obj.content_size > 1024:
                size_kb = obj.content_size / 1024
                return f"{size_kb:.1f} KB"
            return f"{obj.content_size} bytes"
        return "-"
    
    content_size_display.short_description = _("Size")
    
    def has_attachment(self, obj):
        """Show if message has file/image attachment"""
        if obj.image_attachment:
            return format_html(
                '<span class="inline-flex items-center px-2.5 py-0.5 rounded-full text-xs font-medium bg-blue-100 text-blue-800">📷 Image</span>'
            )
        elif obj.file_attachment:
            return format_html(
                '<span class="inline-flex items-center px-2.5 py-0.5 rounded-full text-xs font-medium bg-green-100 text-green-800">📎 File</span>'
            )
        elif obj.content and obj.content_type != 'text':
            return format_html(
                '<span class="inline-flex items-center px-2.5 py-0.5 rounded-full text-xs font-medium bg-gray-100 text-gray-800">🔗 Legacy</span>'
            )
        return "-"
    
    has_attachment.short_description = _("Attachment")
    
    def attachment_preview(self, obj):
        """Display attachment preview in detail view"""
        if obj.image_attachment:
            return format_html(
                '<div><strong>Image:</strong><br/>'
                '<img src="{}" style="max-width: 300px; max-height: 300px; border-radius: 8px; box-shadow: 0 2px 4px rgba(0,0,0,0.1); margin-top: 10px;" />'
                '<br/><a href="{}" target="_blank" style="margin-top: 10px; display: inline-block;">Open in new tab</a></div>',
                obj.image_attachment.url,
                obj.image_attachment.url
            )
        elif obj.file_attachment:
            return format_html(
                '<div><strong>File:</strong><br/>'
                '<a href="{}" target="_blank" style="margin-top: 10px; display: inline-block; padding: 8px 16px; background: #3b82f6; color: white; border-radius: 4px; text-decoration: none;">📥 Download File</a></div>',
                obj.file_attachment.url
            )
        elif obj.content and obj.content_type != 'text':
            return format_html(
                '<div><strong>Legacy URL:</strong><br/><code style="background: #f3f4f6; padding: 4px 8px; border-radius: 4px;">{}</code></div>',
                obj.content
            )
        return "-"
    
    attachment_preview.short_description = _("Attachment Preview")

# Register models with the custom admin site
project_admin_site.register(RoomMessage, RoomMessageAdmin)
project_admin_site.register(ChatMessage, ChatMessageAdmin)
project_admin_site.register(MessageReadStatus, MessageReadStatusAdmin)