import {z} from 'zod'

export type GetApiApiV1ModelsOptions = {baseUrl: string, fetch?: typeof fetch | undefined};

export const modelCapabilities = z.object({caching: z.enum(["implicit", "explicit"]).nullable().optional(), tool_use: z.boolean(), vision: z.boolean()});

export const modelPricing = z.object({input_microdollars_per_million_tokens: z.number().int(), output_microdollars_per_million_tokens: z.number().int(), per_page_microdollars: z.number().int().nullable().optional()});

export const modelInfo = z.object({capabilities: modelCapabilities.nullable().optional(), context_window: z.number().int(), id: z.string(), name: z.string(), object: z.literal("model").optional(), owned_by: z.string(), pricing: modelPricing, type: z.enum(["vlm", "llm", "detect", "ocr", "vision"])});

export const supportedModelsResponse = z.object({data: z.array(modelInfo), object: z.literal("list").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
 * 
 * GET /api/v1/models
 */
export const getApiApiV1Models = async (options: GetApiApiV1ModelsOptions) => {
const {baseUrl, fetch: fetchFn = fetch} = options ?? {}

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

const url = `${baseUrl.replace(/\/+$/, '')}/api/v1/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(supportedModelsResponse, await res.json())
};