import {z} from 'zod'

export type GetApiLitellmGenaiV1betaModelsArgs = {pageSize?: number | undefined, pageToken?: string | undefined};

export type GetApiLitellmGenaiV1betaModelsOptions = {baseUrl?: string | undefined, BearerAuth?: string | undefined, fetch?: typeof fetch | undefined};

export const geminiListModelsResponse = z.object({models: z.array(z.object({name: z.string().optional(), baseModelId: z.string().optional(), version: z.string().optional(), displayName: z.string().optional(), description: z.string().optional(), inputTokenLimit: z.number().int().optional(), outputTokenLimit: z.number().int().optional(), supportedGenerationMethods: z.array(z.string()).optional(), thinking: z.boolean().optional(), temperature: z.number().optional(), maxTemperature: z.number().optional(), topP: z.number().optional(), topK: z.number().int().optional()})).optional(), nextPageToken: z.string().optional()});

export const validateResponse = async <Output>(
  schema: {
    readonly '~standard': {
      readonly validate: (value: unknown) => ({ readonly value: Output; readonly issues?: undefined } | { readonly issues: ReadonlyArray<{ readonly message: string; readonly path?: ReadonlyArray<PropertyKey | { readonly key: PropertyKey }> | undefined }> }) | Promise<{ readonly value: Output; readonly issues?: undefined } | { readonly issues: ReadonlyArray<{ readonly message: string; readonly path?: ReadonlyArray<PropertyKey | { readonly key: PropertyKey }> | undefined }> }>
    }
  },
  value: unknown
): Promise<Output> => {
  const result = await schema['~standard'].validate(value)

  if (result.issues !== undefined) {
    const detail = result.issues
      .map(({ message, path }) =>
        path?.length
          ? `${path.map((segment) => String(typeof segment === 'object' ? segment.key : segment)).join('.')}: ${message}`
          : message
      )
      .join('; ')

    throw new Error(`Response does not match the schema: ${detail}`, { cause: { issues: result.issues } })
  }

  return result.value
};

/**
 * List models (LiteLLM - Gemini format)
 * 
 * GET /litellm/genai/v1beta/models
 * 
 * Also accepts auth: BasicAuth, VirtualKeyAuth, ApiKeyAuth
 */
export const getApiLitellmGenaiV1betaModels = async (args: GetApiLitellmGenaiV1betaModelsArgs, options?: GetApiLitellmGenaiV1betaModelsOptions) => {
const {baseUrl = "http://localhost:8080", fetch: fetchFn = fetch, BearerAuth} = options ?? {}

const query = new URLSearchParams()
const headers = new Headers()
headers.set('accept', "application/json")

if (args.pageSize != null) query.append("pageSize", String(args.pageSize))
if (args.pageToken != null) query.append("pageToken", String(args.pageToken))
if (BearerAuth !== undefined) headers.set('authorization', `Bearer ${BearerAuth}`)

const url = `${baseUrl.replace(/\/+$/, '')}/litellm/genai/v1beta/models${query.size > 0 ? `?${query}` : ''}`

const res = await fetchFn(url, {method: "GET", headers})

if (!res.ok) throw new Error(`Request failed with status ${res.status}`, {cause: {status: res.status, body: await res.text()}})

return validateResponse(geminiListModelsResponse, await res.json())
};