"""Shared configuration helpers for CLI and UI."""

from __future__ import annotations

import re
from typing import Any, Dict, Optional

from chemgraph.models.supported_models import (
    ALCF_DEFAULT_BASE_URL,
    ARGO_DEFAULT_BASE_URL,
    all_supported_models,
    supported_alcf_models,
    supported_anthropic_models,
    supported_argo_models,
    supported_gemini_models,
    supported_ollama_models,
    supported_openai_models,
)


def flatten_config(config: Dict[str, Any]) -> Dict[str, Any]:
    """Flatten nested TOML-like config into top-level keys used by the CLI.

    Parameters
    ----------
    config : dict[str, Any]
        Nested configuration dictionary.

    Returns
    -------
    dict[str, Any]
        Flattened configuration with section names included in keys.
    """
    flattened: Dict[str, Any] = {}

    if "general" in config:
        flattened.update(config["general"])

    for section in ["api", "chemistry", "output"]:
        if section in config:
            for key, value in config[section].items():
                if isinstance(value, dict):
                    for subkey, subvalue in value.items():
                        flattened[f"{section}_{key}_{subkey}"] = subvalue
                else:
                    flattened[f"{section}_{key}"] = value

    for section in ["logging", "features", "security", "advanced"]:
        if section in config:
            if isinstance(config[section], dict):
                for key, value in config[section].items():
                    if isinstance(value, dict):
                        for subkey, subvalue in value.items():
                            flattened[f"{section}_{key}_{subkey}"] = subvalue
                    else:
                        flattened[f"{section}_{key}"] = value
            else:
                flattened[section] = config[section]

    return flattened


def normalize_openai_base_url(base_url: Optional[str]) -> Optional[str]:
    """Normalize Argo-style URLs to OpenAI-compatible /v1 URLs.

    Parameters
    ----------
    base_url : str, optional
        Provider base URL.

    Returns
    -------
    str or None
        Normalized URL, or ``None`` when no URL was provided.
    """
    if not base_url:
        return base_url
    if (
        "apps-dev.inside.anl.gov/argoapi" in base_url
        or "apps.inside.anl.gov/argoapi" in base_url
    ):
        base_url = re.sub(r"/api/v1/resource/(chat|embed)/?$", "/v1", base_url)
        base_url = re.sub(r"/docs/?$", "", base_url)
        base_url = re.sub(r"/api/v1/?$", "/v1", base_url)
        base_url = base_url.rstrip("/")
    return base_url


def get_base_url_for_model_from_nested_config(
    model_name: str, config: Dict[str, Any]
) -> Optional[str]:
    """Resolve provider base URL using nested config structure.

    Parameters
    ----------
    model_name : str
        Model identifier.
    config : dict[str, Any]
        Nested configuration dictionary.

    Returns
    -------
    str or None
        Matching provider base URL, or ``None`` when not configured.
    """
    api = config.get("api", {})

    if model_name in supported_argo_models:
        return normalize_openai_base_url(
            api.get("openai", {}).get("base_url") or ARGO_DEFAULT_BASE_URL
        )
    if model_name in supported_openai_models:
        return normalize_openai_base_url(api.get("openai", {}).get("base_url"))
    if model_name in supported_alcf_models:
        return api.get("alcf", {}).get("base_url") or ALCF_DEFAULT_BASE_URL
    if model_name in supported_anthropic_models:
        return api.get("anthropic", {}).get("base_url")
    if model_name in supported_gemini_models:
        return api.get("google", {}).get("base_url")
    if model_name in supported_ollama_models:
        return api.get("local", {}).get("base_url")
    return normalize_openai_base_url(api.get("openai", {}).get("base_url"))


def get_base_url_for_model_from_flat_config(
    model_name: str, config: Dict[str, Any]
) -> Optional[str]:
    """Resolve provider base URL using flattened config keys.

    Parameters
    ----------
    model_name : str
        Model identifier.
    config : dict[str, Any]
        Flattened configuration dictionary.

    Returns
    -------
    str or None
        Matching provider base URL, or ``None`` when not configured.
    """
    if model_name in supported_argo_models:
        return normalize_openai_base_url(
            config.get("api_openai_base_url") or ARGO_DEFAULT_BASE_URL
        )
    if model_name in supported_openai_models:
        return normalize_openai_base_url(config.get("api_openai_base_url"))
    if model_name in supported_alcf_models:
        return config.get("api_alcf_base_url") or ALCF_DEFAULT_BASE_URL
    if model_name in supported_anthropic_models:
        return config.get("api_anthropic_base_url")
    if model_name in supported_gemini_models:
        return config.get("api_google_base_url")
    if model_name in supported_ollama_models:
        return config.get("api_local_base_url")
    return normalize_openai_base_url(config.get("api_openai_base_url"))


def get_model_options_for_nested_config(config: Dict[str, Any]) -> list[str]:
    """Return model options for UI selection.

    Always show all curated models so users can switch providers from the UI.
    If Argo endpoint is configured, prioritize Argo model IDs at the top.

    Parameters
    ----------
    config : dict[str, Any]
        Nested configuration dictionary.

    Returns
    -------
    list[str]
        Model identifiers for UI selection.
    """
    base_url = config.get("api", {}).get("openai", {}).get("base_url")
    if base_url and "argoapi" in base_url:
        remaining = [m for m in all_supported_models if m not in supported_argo_models]
        return supported_argo_models + remaining
    return all_supported_models


def get_argo_user_from_nested_config(config: Dict[str, Any]) -> Optional[str]:
    """Resolve Argo user from nested config.

    Parameters
    ----------
    config : dict[str, Any]
        Nested configuration dictionary.

    Returns
    -------
    str or None
        Configured Argo username, or ``None``.
    """
    value = config.get("api", {}).get("openai", {}).get("argo_user")
    if isinstance(value, str):
        value = value.strip()
    return value or None


def get_argo_user_from_flat_config(config: Dict[str, Any]) -> Optional[str]:
    """Resolve Argo user from flattened config.

    Parameters
    ----------
    config : dict[str, Any]
        Flattened configuration dictionary.

    Returns
    -------
    str or None
        Configured Argo username, or ``None``.
    """
    value = config.get("api_openai_argo_user")
    if isinstance(value, str):
        value = value.strip()
    return value or None