import {z} from 'zod'

export type SarvamModelAPITransliterateSourceLanguage = 'auto' | 'bn-IN' | 'en-IN' | 'gu-IN' | 'hi-IN' | 'kn-IN' | 'ml-IN' | 'mr-IN' | 'od-IN' | 'pa-IN' | 'ta-IN' | 'te-IN';

export type SarvamModelAPITranslatiterateTargetLanguage = 'bn-IN' | 'en-IN' | 'gu-IN' | 'hi-IN' | 'kn-IN' | 'ml-IN' | 'mr-IN' | 'od-IN' | 'pa-IN' | 'ta-IN' | 'te-IN';

export type SarvamModelAPINumeralsFormat = 'international' | 'native';

export type SarvamModelAPISpokenFormNumeralsFormat = 'english' | 'native';

export type SarvamModelAPITransliterationRequest = {input: string, source_language_code: SarvamModelAPITransliterateSourceLanguage, target_language_code: SarvamModelAPITranslatiterateTargetLanguage, numerals_format?: SarvamModelAPINumeralsFormat | undefined, spoken_form_numerals_language?: SarvamModelAPISpokenFormNumeralsFormat | undefined, spoken_form?: boolean | undefined};

export type CreateApiTransliterateArgs = {'api-subscription-key': string, body: SarvamModelAPITransliterationRequest};

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

export const sarvamModelAPITransliterationResponse = z.object({request_id: z.string().nullable(), transliterated_text: z.string(), source_language_code: z.string()});

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
};

/**
 * Transliterate Text
 * 
 * POST /transliterate
 */
export const createApiTransliterate = async (args: CreateApiTransliterateArgs, options?: CreateApiTransliterateOptions) => {
const {baseUrl = "https://api.sarvam.ai", fetch: fetchFn = fetch} = options ?? {}

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

if (args['api-subscription-key'] != null) headers.set("api-subscription-key", String(args['api-subscription-key']))

const url = `${baseUrl.replace(/\/+$/, '')}/transliterate${query.size > 0 ? `?${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(sarvamModelAPITransliterationResponse, await res.json())
};