"""
Django Admin für den AI Agent.

Erreichbar unter /administration/agent/
"""
from django.contrib import admin
from django.utils.html import format_html

from .models import AgentConfig, ChatSession, ChatMessage


@admin.register(AgentConfig)
class AgentConfigAdmin(admin.ModelAdmin):
    fieldsets = (
        ("Provider", {
            "fields": ("provider", "model_name", "ollama_url"),
        }),
        ("API-Keys (externe Provider)", {
            "fields": ("openai_api_key", "anthropic_api_key"),
            "classes": ("collapse",),
            "description": "Nur ausfüllen wenn nicht Ollama verwendet wird.",
        }),
        ("Verhalten", {
            "fields": ("system_prompt", "allow_write", "chat_retention_days"),
        }),
    )

    def has_add_permission(self, request):
        # Singleton: Hinzufügen nur wenn noch keine Config existiert
        return not AgentConfig.objects.exists()

    def has_delete_permission(self, request, obj=None):
        return False


class ChatMessageInline(admin.TabularInline):
    model = ChatMessage
    fields = ("role", "content_preview", "tool_name", "created_at")
    readonly_fields = ("role", "content_preview", "tool_name", "created_at")
    extra = 0
    can_delete = False
    ordering = ["created_at"]

    def content_preview(self, obj):
        return obj.content[:120] + ("…" if len(obj.content) > 120 else "")
    content_preview.short_description = "Inhalt"


@admin.register(ChatSession)
class ChatSessionAdmin(admin.ModelAdmin):
    list_display = ("title_or_id", "user", "message_count", "created_at", "updated_at")
    list_filter = ("user",)
    search_fields = ("title", "user__username")
    readonly_fields = ("id", "user", "created_at", "updated_at")
    inlines = [ChatMessageInline]
    ordering = ["-updated_at"]

    def title_or_id(self, obj):
        return obj.title or str(obj.id)[:12]
    title_or_id.short_description = "Sitzung"

    def message_count(self, obj):
        return obj.messages.count()
    message_count.short_description = "Nachrichten"