import {z} from 'zod'

export type Ids = Array<string>;

export type CollectionsArray = Array<string>;

export type GetApiSearchArgs = {bbox?: Array<number> | undefined, datetime?: string | undefined, limit?: number | undefined, ids?: Ids | undefined, collections?: CollectionsArray | undefined, sortby?: string | undefined, fields?: string | undefined, query?: string | undefined};

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

export const stacVersion = z.string();

export const stacExtensions = z.array(z.union([z.string(), z.string()]));

export const itemId = z.string();

export const bbox = z.array(z.number());

export const pointGeoJSON = z.object({type: z.literal("Point"), coordinates: z.array(z.number())});

export const multipointGeoJSON = z.object({type: z.literal("MultiPoint"), coordinates: z.array(z.array(z.number()))});

export const linestringGeoJSON = z.object({type: z.literal("LineString"), coordinates: z.array(z.array(z.number()))});

export const multilinestringGeoJSON = z.object({type: z.literal("MultiLineString"), coordinates: z.array(z.array(z.array(z.number())))});

export const polygonGeoJSON = z.object({type: z.literal("Polygon"), coordinates: z.array(z.array(z.array(z.number())))});

export const multipolygonGeoJSON = z.object({type: z.literal("MultiPolygon"), coordinates: z.array(z.array(z.array(z.array(z.number()))))});

export const geometrycollectionGeoJSON = z.object({type: z.literal("GeometryCollection"), geometries: z.array(z.lazy(() => geometryGeoJSON))});

export const geometryGeoJSON: z.ZodType<GeometryGeoJSON> = z.union([pointGeoJSON, multipointGeoJSON, linestringGeoJSON, multilinestringGeoJSON, polygonGeoJSON, multipolygonGeoJSON, geometrycollectionGeoJSON]);

export const itemType = z.literal("Feature");

export const datetime = z.string().nullable();

export const itemProperties = z.object({datetime: datetime}).and(z.record(z.string(), z.object({})));

export const link = z.object({href: z.string(), rel: z.string().optional(), type: z.string().optional(), hreflang: z.string().optional(), title: z.string().optional(), length: z.number().int().optional()});

export const itemAssets = z.record(z.string(), z.object({href: z.string(), title: z.string().optional(), description: z.string().optional(), type: z.string().optional(), roles: z.array(z.string()).optional()}));

export const item = z.object({stac_version: stacVersion, stac_extensions: stacExtensions.optional(), id: itemId, bbox: bbox, geometry: geometryGeoJSON, type: itemType, properties: itemProperties, links: z.array(link), assets: itemAssets});

export const itemCollectionLinks = z.array(link);

export const itemCollectionContext = z.object({returned: z.number().int().gte(0), limit: z.number().int().gte(0).nullable().optional(), matched: z.number().int().gte(0).optional()});

export const itemCollection = z.object({type: z.literal("FeatureCollection"), features: z.array(item), links: itemCollectionLinks.optional(), context: itemCollectionContext.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
};

/**
 * Search STAC items with simple filtering.
 * 
 * GET /search
 */
export const getApiSearch = async (args: GetApiSearchArgs, options?: GetApiSearchOptions) => {
const {baseUrl = "https://geoservice.dlr.de/eoc/ogc/stac/v1", fetch: fetchFn = fetch} = options ?? {}

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

if (args.bbox != null) query.append("bbox", args.bbox.join(','))
if (args.datetime != null) query.append("datetime", String(args.datetime))
if (args.limit != null) query.append("limit", String(args.limit))
if (args.ids != null) query.append("ids", args.ids.join(','))
if (args.collections != null) query.append("collections", args.collections.join(','))
if (args.sortby != null) query.append("sortby", String(args.sortby))
if (args.fields != null) query.append("fields", String(args.fields))
if (args.query != null) query.append("query", String(args.query))

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