import json
import os
from dataclasses import dataclass, field
from pathlib import Path
from typing import Any, Dict, Mapping, Optional


OPENROUTER_BASE_URL = "https://openrouter.ai/api/v1"


@dataclass(frozen=True)
class ProviderConfig:
    name: str
    provider: str
    model: str
    base_url: str
    api_key_env: str
    router_options: Dict[str, Any] = field(default_factory=dict)

    @property
    def api_key(self) -> str:
        return os.environ.get(self.api_key_env, "")


DEFAULT_PROFILES: Dict[str, ProviderConfig] = {
    "default": ProviderConfig(
        name="default",
        provider="openrouter",
        model=os.environ.get("OPENROUTER_MODEL", "openai/gpt-5.6-sol"),
        base_url=OPENROUTER_BASE_URL,
        api_key_env="OPENROUTER_API_KEY",
    ),
    "best_value": ProviderConfig(
        name="best_value",
        provider="openrouter",
        model=os.environ.get("OPENROUTER_BEST_VALUE_MODEL", "openai/gpt-5.6-terra"),
        base_url=OPENROUTER_BASE_URL,
        api_key_env="OPENROUTER_API_KEY",
    ),
    "paper_openai": ProviderConfig(
        name="paper_openai",
        provider="openrouter",
        model="openai/gpt-4o-2024-08-06",
        base_url=OPENROUTER_BASE_URL,
        api_key_env="OPENROUTER_API_KEY",
    ),
    "paper_claude": ProviderConfig(
        name="paper_claude",
        provider="openrouter",
        model="anthropic/claude-3.5-sonnet",
        base_url=OPENROUTER_BASE_URL,
        api_key_env="OPENROUTER_API_KEY",
    ),
    "paper_gemini": ProviderConfig(
        name="paper_gemini",
        provider="openrouter",
        model="google/gemini-pro-1.5",
        base_url=OPENROUTER_BASE_URL,
        api_key_env="OPENROUTER_API_KEY",
    ),
    "fastuse_experimental": ProviderConfig(
        name="fastuse_experimental",
        provider="openrouter",
        model=os.environ.get("OPENROUTER_FASTUSE_MODEL", "google/gemini-3.1-pro-preview"),
        base_url=OPENROUTER_BASE_URL,
        api_key_env="OPENROUTER_API_KEY",
    ),
}


PROFILE_ALIASES = {
    "openrouter": "default",
    "gpt4v": "paper_openai",
    "gpt4v_abl": "paper_openai",
    "claude35sonnet": "paper_claude",
    "gemini15pro": "paper_gemini",
    "gemini31pro": "fastuse_experimental",
    "gemini-3-flash-preview-nothinking": "default",
    "gemini-3-flash-preview-nothinking_abl": "default",
}


def _load_yaml_or_json(path: Path) -> Mapping[str, Any]:
    text = path.read_text()
    if path.suffix.lower() == ".json":
        return json.loads(text)
    try:
        import yaml
    except ImportError as exc:
        raise RuntimeError("Install PyYAML or use a JSON config file.") from exc
    loaded = yaml.safe_load(text)
    return loaded or {}


def _profile_from_mapping(name: str, values: Mapping[str, Any]) -> ProviderConfig:
    return ProviderConfig(
        name=name,
        provider=values["provider"],
        model=values["model"],
        base_url=values.get("base_url", OPENROUTER_BASE_URL),
        api_key_env=values.get("api_key_env", "OPENROUTER_API_KEY"),
        router_options=dict(values.get("router_options", {})),
    )


def load_profiles(path: Optional[str] = None) -> Dict[str, ProviderConfig]:
    profiles = dict(DEFAULT_PROFILES)
    if not path:
        return profiles

    raw = _load_yaml_or_json(Path(path))
    raw_profiles = raw.get("profiles", raw)
    for name, values in raw_profiles.items():
        profiles[name] = _profile_from_mapping(name, values)
    return profiles


def get_model_profile(name: str = "default", config_path: Optional[str] = None) -> ProviderConfig:
    profile_name = PROFILE_ALIASES.get(name, name)
    profiles = load_profiles(config_path)
    if profile_name not in profiles:
        valid = ", ".join(sorted(profiles))
        raise ValueError(f"Unknown model profile '{name}'. Valid profiles: {valid}")
    return profiles[profile_name]


def validate_model_available(profile: ProviderConfig, models_catalog: Optional[Any] = None) -> bool:
    if models_catalog is None:
        return True
    if isinstance(models_catalog, Mapping):
        models_catalog = models_catalog.get("data", models_catalog.keys())
    model_ids = {
        entry.get("id") if isinstance(entry, Mapping) else str(entry)
        for entry in models_catalog
    }
    if profile.model not in model_ids:
        raise ValueError(f"Model {profile.model!r} was not found in the supplied catalog.")
    return True


def sanitize_manifest(
    profile: ProviderConfig,
    request_payload: Mapping[str, Any],
    response_payload: Optional[Mapping[str, Any]] = None,
) -> Dict[str, Any]:
    response_payload = response_payload or {}
    return {
        "provider": profile.provider,
        "profile": profile.name,
        "request_model": request_payload.get("model"),
        "response_model": response_payload.get("model"),
        "base_url": profile.base_url,
        "api_key_env": profile.api_key_env,
        "router_options": dict(profile.router_options),
        "usage": response_payload.get("usage", {}),
    }