from __future__ import annotations

from pydantic import BaseModel, ConfigDict, Field, field_validator, model_validator


class AgentConsumerBinding(BaseModel):
    model_config = ConfigDict(extra="forbid")

    agent_type: str = Field(..., min_length=1, max_length=64)
    bit: int = Field(..., ge=16, le=63)

    @field_validator("agent_type")
    @classmethod
    def _normalize_agent_type(cls, value: str) -> str:
        normalized = value.strip().lower()
        if not normalized:
            raise ValueError("agent_type must not be empty")
        return normalized


class ConsumerRegistry(BaseModel):
    model_config = ConfigDict(extra="forbid")

    bindings: list[AgentConsumerBinding] = Field(default_factory=list)

    @model_validator(mode="after")
    def _validate_unique_bindings(self) -> "ConsumerRegistry":
        by_agent: set[str] = set()
        by_bit: set[int] = set()
        for item in self.bindings:
            if item.agent_type in by_agent:
                raise ValueError(f"duplicate agent_type binding: {item.agent_type}")
            if item.bit in by_bit:
                raise ValueError(f"duplicate visibility bit binding: {item.bit}")
            by_agent.add(item.agent_type)
            by_bit.add(item.bit)
        return self

    def resolve_agent_bit(self, *, agent_type: str) -> int:
        target = agent_type.strip().lower()
        for item in self.bindings:
            if item.agent_type == target:
                return item.bit
        raise ValueError(f"agent visibility bit not configured: {target}")