import {z} from 'zod'

export type ChatCompletionRequest = {model: string, messages: Array<Record<string, never>>, tools?: Array<unknown> | undefined, max_completion_tokens?: number | undefined, max_tokens?: number | undefined, stream?: boolean | undefined, stream_options?: ({include_usage?: boolean | undefined}) | undefined, response_format?: Record<string, never> | undefined, user?: string | undefined, agentlab?: ({schema_version: unknown, tool_calling?: boolean | undefined, vision?: boolean | undefined, structured_output?: boolean | undefined, minimum_context_tokens?: number | undefined}) | undefined} | {[key: string]: unknown};

export type CreateApiV1ChatCompletionsArgs = {'X-AgentLab-Routing'?: ('auto' | 'auto:cost' | 'auto:balanced' | 'auto:quality') | undefined, 'Idempotency-Key'?: string | undefined, body: ChatCompletionRequest};

export type CreateApiV1ChatCompletionsOptions = {baseUrl?: string | undefined, bearer?: string | undefined, fetch?: typeof fetch | undefined};

export const createApiV1ChatCompletionsResponse = z.record(z.string(), z.unknown());

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
};

/**
 * OpenAI Chat Completions
 * 
 * POST /v1/chat/completions
 */
export const createApiV1ChatCompletions = async (args: CreateApiV1ChatCompletionsArgs, options?: CreateApiV1ChatCompletionsOptions) => {
const {baseUrl = "https://api.agentlab.cresclab.com", fetch: fetchFn = fetch, bearer} = options ?? {}

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

if (args['X-AgentLab-Routing'] != null) headers.set("X-AgentLab-Routing", String(args['X-AgentLab-Routing']))
if (args['Idempotency-Key'] != null) headers.set("Idempotency-Key", String(args['Idempotency-Key']))
if (bearer !== undefined) headers.set('authorization', `Bearer ${bearer}`)

const url = `${baseUrl.replace(/\/+$/, '')}/v1/chat/completions${query.size > 0 ? `?${query}` : ''}`

const res = await fetchFn(url, {method: "POST", headers, body: JSON.stringify(args.body)})

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

return validateResponse(createApiV1ChatCompletionsResponse, await res.json())
};