export interface ModelCacheProviderIdOptions {
	apiKey?: string;
	baseUrl?: string;
}

export function getDefaultModelDiscoveryBaseUrl(providerId: string): string | undefined {
	switch (providerId) {
		case "ollama":
			return "http://127.0.0.1:11434";
		case "litellm":
			return Bun.env.LITELLM_BASE_URL ?? "http://localhost:4000/v1";
		case "opencode-go":
			return "https://opencode.ai/zen/go/v1";
		case "opencode-zen":
			return "https://opencode.ai/zen/v1";
		case "vllm":
			return "http://127.0.0.1:8000/v1";
		default:
			return undefined;
	}
}

/** Resolve an Ollama model-cache namespace scoped to the normalized discovery endpoint. */
export function resolveOllamaModelCacheProviderId(providerId: string, baseUrl?: string): string {
	const defaultBaseUrl = getDefaultModelDiscoveryBaseUrl("ollama")!;
	let endpoint = defaultBaseUrl;
	try {
		const parsed = new URL(baseUrl ?? defaultBaseUrl);
		const trimmedPath = parsed.pathname.replace(/\/+$/g, "");
		const nativePath = trimmedPath.endsWith("/v1") ? trimmedPath.slice(0, -3) : trimmedPath;
		endpoint = `${parsed.protocol}//${parsed.host}${nativePath}`;
	} catch {
		// Malformed URLs fall back during discovery, so share the default endpoint's cache.
	}
	return `${providerId}:ollama-models-v1:${Bun.hash(endpoint).toString(36)}`;
}

/** Resolve the cache namespace used by a provider's model-manager options without constructing those options. */
export function resolveModelCacheProviderId(providerId: string, options: ModelCacheProviderIdOptions = {}): string {
	switch (providerId) {
		case "ollama":
			return resolveOllamaModelCacheProviderId(providerId, options.baseUrl);
		case "cursor":
			// v3: max-mode Claude/Gemini rows cached before the 1M context-window
			// discovery fix carry a stale 200k window and must be refetched.
			return "cursor:max-mode-v3";
		case "litellm": {
			const baseUrl = options.baseUrl ?? getDefaultModelDiscoveryBaseUrl(providerId)!;
			return `litellm:rich-v5:${Bun.hash(baseUrl).toString(36)}`;
		}
		case "opencode-go":
		case "opencode-zen": {
			const configuredBaseUrl = options.baseUrl ?? getDefaultModelDiscoveryBaseUrl(providerId)!;
			const trimmedBaseUrl = configuredBaseUrl.endsWith("/") ? configuredBaseUrl.slice(0, -1) : configuredBaseUrl;
			const discoveryBaseUrl = trimmedBaseUrl.endsWith("/v1") ? trimmedBaseUrl : `${trimmedBaseUrl}/v1`;
			const scope = `${options.apiKey ?? ""}\u0000${discoveryBaseUrl}`;
			return `${providerId}:models-v1:${Bun.hash(scope).toString(36)}`;
		}
		case "openrouter":
			return "openrouter:pseudo-api";
		case "vllm": {
			const baseUrl = options.baseUrl ?? getDefaultModelDiscoveryBaseUrl(providerId)!;
			return `vllm:${Bun.hash(baseUrl).toString(36)}`;
		}
		default:
			return providerId;
	}
}