"""Ollama client wrapper for LLM interactions."""
import ollama as ollama_lib


class OllamaClient:
    """Client for interacting with Ollama LLM."""

    def __init__(self, host: str = "http://localhost:11434", model: str = "llama3"):
        """Initialize Ollama client.

        Args:
            host: Ollama server URL.
            model: Default model to use.
        """
        self.host = host
        self.model = model
        ollama_lib.host = host

    def check_connection(self) -> bool:
        """Check if Ollama is running and accessible.

        Returns:
            True if connection successful, False otherwise.
        """
        try:
            ollama_lib.list()
            return True
        except Exception:
            return False

    def check_model_available(self, model: str) -> bool:
        """Check if a specific model is available.

        Args:
            model: Model name to check.

        Returns:
            True if model is available, False otherwise.
        """
        try:
            response = ollama_lib.list()
            return any(m["name"] == model or m["name"].startswith(model)
                      for m in response.get("models", []))
        except Exception:
            return False

    def generate_commit_message(
        self, diff: str, prompt: str, model: str | None = None
    ) -> str:
        """Generate a commit message from diff.

        Args:
            diff: Git diff to analyze.
            prompt: Prompt template to use.
            model: Optional model override.

        Returns:
            Generated commit message.
        """
        response = ollama_lib.chat(
            model=model or self.model,
            messages=[
                {
                    "role": "system",
                    "content": "You are a helpful assistant that generates git commit messages following conventional commit format. Be concise and descriptive.",
                },
                {
                    "role": "user",
                    "content": f"{prompt}\n\nGit diff to analyze:\n\n{diff}",
                },
            ],
            stream=False,
        )
        return response["message"]["content"]

    def generate_changelog(
        self, commits: str, prompt: str, model: str | None = None
    ) -> str:
        """Generate changelog from commits.

        Args:
            commits: Commit history to analyze.
            prompt: Prompt template to use.
            model: Optional model override.

        Returns:
            Generated changelog.
        """
        response = ollama_lib.chat(
            model=model or self.model,
            messages=[
                {
                    "role": "system",
                    "content": "You are a helpful assistant that generates changelogs from git commit history. Group changes by type and create a well-structured markdown changelog.",
                },
                {
                    "role": "user",
                    "content": f"{prompt}\n\nCommit history to analyze:\n\n{commits}",
                },
            ],
            stream=False,
        )
        return response["message"]["content"]

    def list_models(self) -> list[dict]:
        """List available Ollama models.

        Returns:
            List of available models with their details.
        """
        try:
            response = ollama_client.list()
            return response.get("models", [])
        except Exception:
            return []

    def pull_model(self, model: str) -> bool:
        """Pull a model from Ollama registry.

        Args:
            model: Model name to pull.

        Returns:
            True if successful, False otherwise.
        """
        try:
            ollama_lib.pull(model)
            return True
        except Exception:
            return False


def get_ollama_client(host: str = "http://localhost:11434", model: str = "llama3") -> OllamaClient:
    """Get OllamaClient instance.

    Args:
        host: Ollama server URL.
        model: HTTP_HOST, model to use.

    Returns:
        OllamaClient instance.
    """
    return OllamaClient(host=host, model=model)