from __future__ import annotations

from dataclasses import dataclass
from typing import Dict, Iterator, List

from .base import AgentProvider, AssistantTurn, StreamEvent


@dataclass
class ScriptedProvider(AgentProvider):
    """Deterministic provider for tests and demos."""

    turns: List[AssistantTurn]

    def generate(self, messages: List[Dict[str, str]], tools: List[Dict[str, str]]) -> AssistantTurn:
        if not self.turns:
            raise RuntimeError("ScriptedProvider ran out of scripted turns")
        return self.turns.pop(0)

    def stream_generate(self, messages: List[Dict[str, str]], tools: List[Dict[str, str]]) -> Iterator[StreamEvent]:
        turn = self.generate(messages, tools)
        if turn.reasoning:
            yield StreamEvent(type="reasoning", delta=turn.reasoning)
        if turn.content:
            yield StreamEvent(type="content", delta=turn.content)
        yield StreamEvent(type="turn", turn=turn)