from django.contrib import admin
from django.utils.html import format_html
from unfold.admin import ModelAdmin, TabularInline
from unfold.decorators import display
from .models import Activity, ActivitySignup, Topic, Reply, TopicMedia

class ActivitySignupInline(TabularInline):
    model = ActivitySignup
    extra = 0
    readonly_fields = ('signup_time',)
    fields = ('user', 'status', 'signup_time')
    autocomplete_fields = ['user']
    can_delete = True
    show_change_link = True

class ReplyInline(TabularInline):
    model = Reply
    extra = 0
    readonly_fields = ('created_at',)
    fields = ('content', 'author', 'created_at')
    can_delete = True
    show_change_link = True

class TopicMediaInline(TabularInline):
    model = TopicMedia
    extra = 0
    fields = ('file', 'media_type', 'created_at')
    readonly_fields = ('created_at',)
    can_delete = True

@admin.register(Activity)
class ActivityAdmin(ModelAdmin):
    list_display = ('title', 'banner_display', 'start_time', 'location', 'signup_count', 'is_active', 'created_at')
    list_filter = ('is_active', 'start_time')
    search_fields = ('title', 'location')
    inlines = [ActivitySignupInline]
    
    fieldsets = (
        ('基本信息', {
            'fields': ('title', 'description', 'banner', 'banner_url', 'is_active')
        }),
        ('时间与地点', {
            'fields': ('start_time', 'end_time', 'location'),
            'classes': ('tab',)
        }),
        ('报名设置', {
            'fields': ('max_participants',)
        }),
    )

    @display(description="Banner")
    def banner_display(self, obj):
        if obj.banner:
            return format_html('<img src="{}" height="50" style="border-radius: 4px;" />', obj.banner.url)
        elif obj.banner_url:
            return format_html('<img src="{}" height="50" style="border-radius: 4px;" />', obj.banner_url)
        return "暂无"

    @display(description="报名人数")
    def signup_count(self, obj):
        return obj.signups.count()

@admin.register(ActivitySignup)
class ActivitySignupAdmin(ModelAdmin):
    list_display = ('activity', 'user', 'signup_time', 'status_label')
    list_filter = ('status', 'signup_time', 'activity')
    search_fields = ('user__nickname', 'activity__title')
    autocomplete_fields = ['activity', 'user']
    
    fieldsets = (
        ('报名详情', {
            'fields': ('activity', 'user', 'status')
        }),
        ('时间信息', {
            'fields': ('signup_time',),
            'classes': ('collapse',)
        }),
    )
    readonly_fields = ('signup_time',)

    @display(
        description="状态",
        label={
            "pending": "warning",
            "confirmed": "success",
            "cancelled": "danger",
        }
    )
    def status_label(self, obj):
        return obj.status

@admin.register(Topic)
class TopicAdmin(ModelAdmin):
    list_display = ('title', 'author', 'get_related_item', 'reply_count', 'view_count', 'is_pinned', 'created_at')
    list_filter = ('is_pinned', 'created_at', 'related_product', 'related_service', 'related_course')
    search_fields = ('title', 'content', 'author__nickname')
    autocomplete_fields = ['author', 'related_product', 'related_service', 'related_course']
    inlines = [TopicMediaInline, ReplyInline]
    
    fieldsets = (
        ('帖子内容', {
            'fields': ('title', 'content', 'is_pinned')
        }),
        ('关联信息', {
            'fields': ('author', 'related_product', 'related_service', 'related_course'),
            'description': '可关联 硬件、服务 或 课程，用于技术求助或讨论'
        }),
        ('统计数据', {
            'fields': ('view_count', 'created_at', 'updated_at'),
            'classes': ('collapse',)
        }),
    )
    readonly_fields = ('created_at', 'updated_at')

    @display(description="关联项目")
    def get_related_item(self, obj):
        if obj.related_product:
            return f"[硬件] {obj.related_product.name}"
        if obj.related_service:
            return f"[服务] {obj.related_service.title}"
        if obj.related_course:
            return f"[课程] {obj.related_course.title}"
        return "-"

    @display(description="回复数")
    def reply_count(self, obj):
        return obj.replies.count()

@admin.register(Reply)
class ReplyAdmin(ModelAdmin):
    list_display = ('short_content', 'topic', 'author', 'created_at')
    list_filter = ('created_at',)
    search_fields = ('content', 'author__nickname', 'topic__title')
    autocomplete_fields = ['author', 'topic', 'reply_to']
    inlines = [TopicMediaInline]
    
    fieldsets = (
        ('回复内容', {
            'fields': ('topic', 'reply_to', 'content')
        }),
        ('发布信息', {
            'fields': ('author', 'created_at')
        }),
    )
    readonly_fields = ('created_at',)

    @display(description="内容摘要")
    def short_content(self, obj):
        return obj.content[:30] + '...' if len(obj.content) > 30 else obj.content

@admin.register(TopicMedia)
class TopicMediaAdmin(ModelAdmin):
    list_display = ('id', 'media_type', 'file_preview', 'topic', 'reply', 'created_at')
    list_filter = ('media_type', 'created_at')
    search_fields = ('file', 'topic__title')
    autocomplete_fields = ['topic', 'reply']
    
    @display(description="预览")
    def file_preview(self, obj):
        if obj.media_type == 'image':
            return format_html('<img src="{}" height="50" style="border-radius: 4px;" />', obj.file.url)
        return obj.file.name