import {z} from 'zod'

export type GetApiV1ModelsModelIdSchemaArgs = {model_id: string};

export type GetApiV1ModelsModelIdSchemaOptions = {baseUrl: string, BearerAuth?: string | undefined, fetch?: typeof fetch | undefined};

export const string = z.object({kind: z.literal("string").optional()});

export const boolean = z.object({kind: z.literal("boolean").optional()});

export const categoricalString = z.object({kind: z.literal("categorical_string").optional(), values: z.array(z.string())});

export const categoricalInteger = z.object({kind: z.literal("categorical_integer").optional(), values: z.array(z.number().int())});

export const rangeInt = z.object({min: z.number().int().nullable().optional(), max: z.number().int().nullable().optional()});

export const integer = z.object({kind: z.literal("integer").optional(), bits: z.union([z.literal(8), z.literal(16), z.literal(32), z.literal(64)]), signed: z.boolean().optional(), range: rangeInt.nullable().optional()});

export const rangeFloat = z.object({min: z.number().nullable().optional(), max: z.number().nullable().optional()});

export const real = z.object({kind: z.literal("real").optional(), bits: z.union([z.literal(16), z.literal(32), z.literal(64)]), range: rangeFloat.nullable().optional()});

export const decimal = z.object({kind: z.literal("decimal").optional(), bits: z.union([z.literal(32), z.literal(64), z.literal(128), z.literal(256)]), precision: z.number().int().gte(1), scale: z.number().int()});

export const datetime = z.object({kind: z.literal("datetime").optional()});

export const dataType = z.discriminatedUnion("kind", [string, boolean, categoricalString, categoricalInteger, integer, real, decimal, datetime]);

export const schemaColumn = z.object({dtype: z.enum(["float", "int", "bool", "categorical"]), datatype: dataType.nullable().optional(), categories: z.array(z.unknown()).nullable().optional(), unknown_code: z.number().int().nullable().optional()});

export const schemaTarget = z.object({dtype: z.enum(["float", "int", "bool"])});

export const schemaManifest = z.object({feature_names: z.array(z.string()), columns: z.record(z.string(), schemaColumn), target: schemaTarget, is_sequence: z.boolean().optional(), id_column: z.string().nullable().optional(), timestamp_column: z.string().nullable().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
};

/**
 * Get Schema
 * 
 * GET /v1/models/{model_id}/schema
 */
export const getApiV1ModelsModelIdSchema = async (args: GetApiV1ModelsModelIdSchemaArgs, options: GetApiV1ModelsModelIdSchemaOptions) => {
const {baseUrl, fetch: fetchFn = fetch, BearerAuth} = options ?? {}

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

if (BearerAuth !== undefined) headers.set('authorization', `Bearer ${BearerAuth}`)

const url = `${baseUrl.replace(/\/+$/, '')}/v1/models/${encodeURIComponent(String(args.model_id))}/schema${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(schemaManifest, await res.json())
};