from datetime import datetime

from pydantic import BaseModel, EmailStr, Field

from app.db.models import ClassMembership, User


def normalize_class_permissions(permissions: list[str]) -> list[str]:
    return [
        permission
        for permission in permissions
        if permission not in {"class_view", "member_view", "member_manage", "committee_manage"}
    ]


class MembershipOut(BaseModel):
    id: int
    class_id: int
    class_name: str | None
    membership_role: str
    committee_role: str | None = None
    class_permissions: list[str]


class UserOut(BaseModel):
    id: int
    email: str
    name: str
    student_id: str | None
    role: str
    status: str
    industry: str | None
    company: str | None
    position: str | None
    skills_tags: list[str] | None
    wechat_id: str | None
    phone: str | None
    avatar_url: str | None
    bio: str | None
    created_at: datetime
    memberships: list[MembershipOut]
    active_membership: MembershipOut | None = None
    enabled_modules: list[str] | None = None


class UserPublic(BaseModel):
    id: int
    name: str
    student_id: str | None
    industry: str | None
    company: str | None
    position: str | None
    committee_role: str | None = None
    wechat_id: str | None
    phone: str | None
    avatar_url: str | None
    bio: str | None


class UserListItem(BaseModel):
    id: int
    email: str
    name: str
    student_id: str | None
    role: str
    status: str
    industry: str | None
    company: str | None
    committee_role: str | None = None
    class_permissions: list[str]
    created_at: datetime
    memberships: list[MembershipOut]
    active_membership: MembershipOut | None = None


class UserUpdate(BaseModel):
    email: EmailStr | None = None
    name: str | None = None
    industry: str | None = None
    company: str | None = None
    position: str | None = None
    wechat_id: str | None = None
    phone: str | None = None
    bio: str | None = None


class UserStatusUpdate(BaseModel):
    status: str
    role: str | None = None


class UserRoleUpdate(BaseModel):
    role: str


class TeacherCreateRequest(BaseModel):
    class_id: int
    name: str = Field(min_length=1, max_length=100)
    email: EmailStr
    password: str = Field(min_length=8, max_length=128)


class TeacherCreateResponse(BaseModel):
    message: str
    user: UserOut


class TeacherAssignRequest(BaseModel):
    class_id: int
    email: EmailStr


class TeacherAssignResponse(BaseModel):
    message: str
    user: UserOut


class CommitteeRoleUpdate(BaseModel):
    class_id: int
    committee_role: str | None = None


class ClassPermissionsUpdate(BaseModel):
    class_id: int
    class_permissions: list[str]


class TokenResponse(BaseModel):
    token: str
    user: UserOut


def build_membership_out(membership: ClassMembership) -> MembershipOut:
    return MembershipOut(
        id=membership.id,
        class_id=membership.class_id,
        class_name=membership.class_.name if membership.class_ else None,
        membership_role=membership.membership_role,
        committee_role=membership.committee_role,
        class_permissions=normalize_class_permissions(membership.get_class_permissions()),
    )


def build_user_out(user: User, class_id: int | None = None) -> UserOut:
    active_membership = user.get_membership(class_id) if class_id is not None else user.get_default_membership()
    memberships = [build_membership_out(membership) for membership in user.memberships]
    return UserOut(
        id=user.id,
        email=user.email,
        name=user.name,
        student_id=user.student_id,
        role=user.role,
        status=user.status,
        industry=user.industry,
        company=user.company,
        position=user.position,
        skills_tags=user.get_skills_list(),
        wechat_id=user.wechat_id,
        phone=user.phone,
        avatar_url=user.avatar_url,
        bio=user.bio,
        created_at=user.created_at,
        memberships=memberships,
        active_membership=build_membership_out(active_membership) if active_membership else None,
    )


def build_user_list_item(user: User, class_id: int | None = None) -> UserListItem:
    active_membership = user.get_membership(class_id) if class_id is not None else user.get_default_membership()
    memberships = [build_membership_out(membership) for membership in user.memberships]
    return UserListItem(
        id=user.id,
        email=user.email,
        name=user.name,
        student_id=user.student_id,
        role=user.role,
        status=user.status,
        industry=user.industry,
        company=user.company,
        committee_role=active_membership.committee_role if active_membership else None,
        class_permissions=normalize_class_permissions(active_membership.get_class_permissions()) if active_membership else [],
        created_at=user.created_at,
        memberships=memberships,
        active_membership=build_membership_out(active_membership) if active_membership else None,
    )