"""Resolves `LLM_PROVIDER` to a concrete provider instance. Never imported
directly by prompt task modules or services - always go through
`get_llm_provider()` so swapping providers stays a one-line config change.
"""

from __future__ import annotations

from app.analysis.llm.base import LLMProvider
from app.analysis.llm.mock import MockLLMProvider
from app.core.config import Settings, get_settings


def get_llm_provider(settings: Settings | None = None) -> LLMProvider:
    settings = settings or get_settings()

    if settings.llm_provider == "anthropic":
        from app.analysis.llm.anthropic_provider import AnthropicLLMProvider

        return AnthropicLLMProvider(settings)

    if settings.llm_provider == "ollama":
        from app.analysis.llm.ollama_provider import OllamaLLMProvider

        return OllamaLLMProvider(settings)

    if settings.llm_provider == "gemini":
        from app.analysis.llm.gemini_provider import GeminiLLMProvider

        return GeminiLLMProvider(settings)

    return MockLLMProvider()