from django.conf import settings
from django.contrib.auth import get_user_model
from django.contrib.auth.models import Group, Permission
from django.contrib.contenttypes.models import ContentType

from apps.accounts.menus import DEFAULT_MENUS
from apps.accounts.models import MenuItem, UserGroup
from apps.accounts.permissions import DEFAULT_GROUPS, PERMISSIONS


def seed_permissions() -> dict[str, Permission]:
    content_type, _ = ContentType.objects.get_or_create(
        app_label="system",
        model="platformpermission",
    )

    permissions_by_codename: dict[str, Permission] = {}
    for spec in PERMISSIONS:
        permission, _ = Permission.objects.get_or_create(
            content_type=content_type,
            codename=spec.codename,
            defaults={"name": spec.name},
        )
        if permission.name != spec.name:
            permission.name = spec.name
            permission.save(update_fields=["name"])
        permissions_by_codename[spec.codename] = permission
    return permissions_by_codename


def seed_roles(permissions_by_codename: dict[str, Permission]) -> None:
    for group_name, codenames in DEFAULT_GROUPS.items():
        group, _ = Group.objects.get_or_create(name=group_name)
        group.permissions.set(permissions_by_codename[codename] for codename in codenames)


def seed_user_groups() -> None:
    UserGroup.objects.update_or_create(
        code="default",
        defaults={
            "name": "默认用户组",
            "description": "系统初始化创建的默认业务用户组。",
            "is_active": True,
        },
    )


def seed_menus() -> None:
    menus_by_code: dict[str, MenuItem] = {}
    for spec in DEFAULT_MENUS:
        parent = menus_by_code.get(spec.parent_code) if spec.parent_code else None
        menu, _ = MenuItem.objects.update_or_create(
            code=spec.code,
            defaults={
                "title": spec.title,
                "path": spec.path,
                "icon": spec.icon,
                "parent": parent,
                "sort_order": spec.sort_order,
                "permission_code": spec.permission_code,
                "is_visible": spec.is_visible,
                "is_enabled": spec.is_enabled,
            },
        )
        menus_by_code[spec.code] = menu


def seed_admin_user() -> None:
    username = getattr(settings, "DJANGO_SUPERUSER_USERNAME", None) or "admin"
    password = getattr(settings, "DJANGO_SUPERUSER_PASSWORD", None) or "admin12345"
    email = getattr(settings, "DJANGO_SUPERUSER_EMAIL", None) or "admin@example.com"
    user_model = get_user_model()
    user, created = user_model.objects.get_or_create(
        username=username,
        defaults={
            "email": email,
            "is_staff": True,
            "is_superuser": True,
        },
    )
    changed_fields: list[str] = []
    if user.email != email:
        user.email = email
        changed_fields.append("email")
    if not user.is_staff:
        user.is_staff = True
        changed_fields.append("is_staff")
    if not user.is_superuser:
        user.is_superuser = True
        changed_fields.append("is_superuser")
    if created or not user.check_password(password):
        user.set_password(password)
        changed_fields.append("password")
    if changed_fields:
        user.save(update_fields=changed_fields)
    admin_role = Group.objects.get(name="系统管理员")
    user.groups.add(admin_role)


def bootstrap_governance() -> None:
    permissions_by_codename = seed_permissions()
    seed_roles(permissions_by_codename)
    seed_user_groups()
    seed_menus()
    seed_admin_user()