import { parseJWT } from '@sphereon/oid4vc-common'
import { DcqlQuery } from 'dcql'

import { PresentationDefinitionWithLocation } from '../authorization-response'
import { Dcql } from '../authorization-response'
import { PresentationExchange } from '../authorization-response/PresentationExchange'
import { fetchByReferenceOrUseByValue, removeNullUndefined } from '../helpers'
import { authorizationRequestVersionDiscovery } from '../helpers/SIOPSpecVersion'
import { RequestObject } from '../request-object'
import {
  AuthorizationRequestPayload,
  getJwtVerifierWithContext,
  getRequestObjectJwtVerifier,
  PassBy,
  RequestObjectJwt,
  RequestObjectPayload,
  RequestStateInfo,
  ResponseType,
  ResponseURIType,
  RPRegistrationMetadataPayload,
  Schema,
  SIOPErrors,
  SupportedVersion,
  VerifiedAuthorizationRequest,
} from '../types'

import { assertValidAuthorizationRequestOpts, assertValidVerifyAuthorizationRequestOpts } from './Opts'
import { assertValidRPRegistrationMedataPayload, createAuthorizationRequestPayload } from './Payload'
import { URI } from './URI'
import { CreateAuthorizationRequestOpts, VerifyAuthorizationRequestOpts } from './types'

export class AuthorizationRequest {
  private readonly _requestObject?: RequestObject
  private readonly _payload: AuthorizationRequestPayload
  private readonly _options: CreateAuthorizationRequestOpts | undefined
  private _uri: URI | undefined

  private constructor(payload: AuthorizationRequestPayload, requestObject?: RequestObject, opts?: CreateAuthorizationRequestOpts, uri?: URI) {
    this._options = opts
    this._payload = removeNullUndefined(payload)
    this._requestObject = requestObject
    this._uri = uri
  }

  public static async fromUriOrJwt(jwtOrUri: string | URI): Promise<AuthorizationRequest> {
    if (!jwtOrUri) {
      throw Error(SIOPErrors.NO_REQUEST)
    }
    return typeof jwtOrUri === 'string' && jwtOrUri.startsWith('ey')
      ? await AuthorizationRequest.fromJwt(jwtOrUri)
      : await AuthorizationRequest.fromURI(jwtOrUri)
  }

  public static async fromPayload(payload: AuthorizationRequestPayload): Promise<AuthorizationRequest> {
    if (!payload) {
      throw Error(SIOPErrors.NO_REQUEST)
    }
    const requestObject = await RequestObject.fromAuthorizationRequestPayload(payload)
    return new AuthorizationRequest(payload, requestObject)
  }

  public static async fromOpts(opts: CreateAuthorizationRequestOpts, requestObject?: RequestObject): Promise<AuthorizationRequest> {
    // todo: response_uri/redirect_uri is not hooked up from opts!
    if (!opts || !opts.requestObject) {
      throw Error(SIOPErrors.BAD_PARAMS)
    }
    assertValidAuthorizationRequestOpts(opts)

    const requestObjectArg =
      opts.requestObject.passBy !== PassBy.NONE ? (requestObject ? requestObject : await RequestObject.fromOpts(opts)) : undefined
    // opts?.payload was removed before, but it's not clear atm why opts?.payload was removed
    const requestPayload = opts?.payload ? await createAuthorizationRequestPayload(opts, requestObjectArg) : undefined
    return new AuthorizationRequest(requestPayload, requestObjectArg, opts)
  }

  get payload(): AuthorizationRequestPayload {
    return this._payload
  }

  get requestObject(): RequestObject | undefined {
    return this._requestObject
  }

  get options(): CreateAuthorizationRequestOpts | undefined {
    return this._options
  }

  public hasRequestObject(): boolean {
    return this.requestObject !== undefined
  }

  public async getSupportedVersion() {
    if (this.options?.version) {
      return this.options.version
    } else if (this._uri?.encodedUri?.startsWith(Schema.OPENID_VC) || this._uri?.scheme?.startsWith(Schema.OPENID_VC)) {
      return SupportedVersion.JWT_VC_PRESENTATION_PROFILE_v1
    }

    return (await this.getSupportedVersionsFromPayload())[0]
  }

  public async getSupportedVersionsFromPayload(): Promise<SupportedVersion[]> {
    const mergedPayload = { ...this.payload, ...(await this.requestObject?.getPayload()) }
    return authorizationRequestVersionDiscovery(mergedPayload)
  }

  async uri(): Promise<URI> {
    if (!this._uri) {
      this._uri = await URI.fromAuthorizationRequest(this)
    }
    return this._uri
  }

  /**
   * Verifies a SIOP Request JWT on OP side
   *
   * @param opts
   */
  async verify(opts: VerifyAuthorizationRequestOpts): Promise<VerifiedAuthorizationRequest> {
    assertValidVerifyAuthorizationRequestOpts(opts)

    let requestObjectPayload: RequestObjectPayload | undefined = undefined

    const jwt = await this.requestObjectJwt()
    const parsedJwt = jwt ? parseJWT(jwt) : undefined

    if (parsedJwt) {
      requestObjectPayload = parsedJwt.payload as RequestObjectPayload

      const jwtVerifier = await getRequestObjectJwtVerifier({ ...parsedJwt, payload: requestObjectPayload }, { raw: jwt })
      const result = await opts.verifyJwtCallback(jwtVerifier, { ...parsedJwt, raw: jwt })
      if (!result) {
        throw Error(SIOPErrors.ERROR_VERIFYING_SIGNATURE)
      }

      // verify the verifier attestation
      if (requestObjectPayload.client_id_scheme === 'verifier_attestation') {
        const jwtVerifier = await getJwtVerifierWithContext(parsedJwt, { type: 'verifier-attestation' })
        const result = await opts.verifyJwtCallback(jwtVerifier, { ...parsedJwt, raw: jwt })
        if (!result) {
          throw Error(SIOPErrors.ERROR_VERIFYING_SIGNATURE)
        }
      }

      if (this.hasRequestObject() && !this.payload.request_uri) {
        // Put back the request object as that won't be present yet
        this.payload.request = jwt
      }
    }

    // AuthorizationRequest.assertValidRequestObject(origAuthenticationRequest);

    // We use the orig request for default values, but the JWT payload contains signed request object properties
    const mergedPayload = { ...this.payload, ...(requestObjectPayload ? requestObjectPayload : {}) }
    if (opts.state && mergedPayload.state !== opts.state) {
      throw new Error(`${SIOPErrors.BAD_STATE} payload: ${mergedPayload.state}, supplied: ${opts.state}`)
    } else if (opts.nonce && mergedPayload.nonce !== opts.nonce) {
      throw new Error(`${SIOPErrors.BAD_NONCE} payload: ${mergedPayload.nonce}, supplied: ${opts.nonce}`)
    }

    const registrationPropertyKey = mergedPayload['registration'] || mergedPayload['registration_uri'] ? 'registration' : 'client_metadata'
    let registrationMetadataPayload: RPRegistrationMetadataPayload
    if (mergedPayload[registrationPropertyKey] || mergedPayload[`${registrationPropertyKey}_uri`]) {
      registrationMetadataPayload = await fetchByReferenceOrUseByValue(
        mergedPayload[`${registrationPropertyKey}_uri`],
        mergedPayload[registrationPropertyKey],
      )
      assertValidRPRegistrationMedataPayload(registrationMetadataPayload)
      // TODO: We need to do something with the metadata probably
    } /*else { // this makes test mattr.launchpad.spec.ts fail why was this check added?
      return Promise.reject(Error(`could not fetch registrationMetadataPayload due to missing payload key ${registrationPropertyKey}`))
    }
    */
    // When the response_uri parameter is present, the redirect_uri Authorization Request parameter MUST NOT be present. If the redirect_uri Authorization Request parameter is present when the Response Mode is direct_post, the Wallet MUST return an invalid_request Authorization Response error.
    let responseURIType: ResponseURIType
    let responseURI: string
    if (mergedPayload.redirect_uri && mergedPayload.response_uri) {
      throw new Error(`${SIOPErrors.INVALID_REQUEST}, redirect_uri cannot be used together with response_uri`)
    } else if (mergedPayload.redirect_uri) {
      responseURIType = 'redirect_uri'
      responseURI = mergedPayload.redirect_uri
    } else if (mergedPayload.response_uri) {
      responseURIType = 'response_uri'
      responseURI = mergedPayload.response_uri
    } else if (mergedPayload.client_id_scheme === 'redirect_uri' && mergedPayload.client_id) {
      responseURIType = 'redirect_uri'
      responseURI = mergedPayload.client_id
    } else {
      throw new Error(`${SIOPErrors.INVALID_REQUEST}, redirect_uri or response_uri is needed`)
    }

    // TODO see if this is too naive. The OpenID conformance test explicitly tests for this
    // But the spec says: The client_id and client_id_scheme MUST be omitted in unsigned requests defined in Appendix A.3.1.
    // So I would expect client_id_scheme and client_id to be undefined when the JWT header has alg: none
    if (mergedPayload.client_id && mergedPayload.client_id_scheme === 'redirect_uri' && mergedPayload.client_id !== responseURI) {
      throw Error(
        `${SIOPErrors.INVALID_REQUEST}, response_uri does not match the client_id provided by the verifier which is required for client_id_scheme redirect_uri`,
      )
    }

    // TODO: we need to verify somewhere that if response_mode is direct_post, that the response_uri may be present,
    // BUT not both redirect_uri and response_uri. What is the best place to do this?

    const presentationDefinitions: PresentationDefinitionWithLocation[] = await PresentationExchange.findValidPresentationDefinitions(
      mergedPayload,
      await this.getSupportedVersion(),
    )

    const dcqlQuery = await Dcql.findValidDcqlQuery(mergedPayload)

    return {
      jwt,
      payload: parsedJwt?.payload,
      issuer: parsedJwt?.payload.iss,
      responseURIType,
      responseURI,
      clientIdScheme: mergedPayload.client_id_scheme,
      correlationId: opts.correlationId,
      authorizationRequest: this,
      verifyOpts: opts,
      dcqlQuery,
      presentationDefinitions,
      registrationMetadataPayload,
      requestObject: this.requestObject,
      authorizationRequestPayload: this.payload,
      versions: await this.getSupportedVersionsFromPayload(),
    }
  }

  static async verify(requestOrUri: string, verifyOpts: VerifyAuthorizationRequestOpts) {
    assertValidVerifyAuthorizationRequestOpts(verifyOpts)
    const authorizationRequest = await AuthorizationRequest.fromUriOrJwt(requestOrUri)
    return await authorizationRequest.verify(verifyOpts)
  }

  public async requestObjectJwt(): Promise<RequestObjectJwt | undefined> {
    return await this.requestObject?.toJwt()
  }

  private static async fromJwt(jwt: string): Promise<AuthorizationRequest> {
    if (!jwt) {
      throw Error(SIOPErrors.BAD_PARAMS)
    }
    const requestObject = await RequestObject.fromJwt(jwt)
    const payload: AuthorizationRequestPayload = { ...(await requestObject.getPayload()) } as AuthorizationRequestPayload
    // Although this was a RequestObject we instantiate it as AuthzRequest and then copy in the JWT as the request Object
    payload.request = jwt
    return new AuthorizationRequest({ ...payload }, requestObject)
  }

  private static async fromURI(uri: URI | string): Promise<AuthorizationRequest> {
    if (!uri) {
      throw Error(SIOPErrors.BAD_PARAMS)
    }
    const uriObject = typeof uri === 'string' ? await URI.fromUri(uri) : uri
    const requestObject = await RequestObject.fromJwt(uriObject.requestObjectJwt)
    return new AuthorizationRequest(uriObject.authorizationRequestPayload, requestObject, undefined, uriObject)
  }

  public async toStateInfo(): Promise<RequestStateInfo> {
    const requestObject = await this.requestObject.getPayload()
    return {
      client_id: this.options.clientMetadata.client_id,
      iat: requestObject.iat ?? this.payload.iat,
      nonce: requestObject.nonce ?? this.payload.nonce,
      state: this.payload.state,
    }
  }

  public async containsResponseType(singleType: ResponseType | string): Promise<boolean> {
    const responseType: string = this.getMergedProperty('response_type')
    return responseType?.includes(singleType) === true
  }

  public getMergedProperty<T>(key: string): T | undefined {
    const merged = this.mergedPayloads()
    return merged[key] as T
  }

  public mergedPayloads(): RequestObjectPayload {
    const requestObjectPayload = this.requestObject?.getPayload()
    const mergedPayload = { ...this.payload, ...requestObjectPayload }
    if (mergedPayload.scope && typeof mergedPayload.scope !== 'string') {
      //  test mattr.launchpad.spec.ts does not supply a scope value
      throw new Error('Invalid scope value')
    }
    return mergedPayload as RequestObjectPayload
  }

  public async getPresentationDefinitions(version?: SupportedVersion): Promise<PresentationDefinitionWithLocation[] | undefined> {
    return await PresentationExchange.findValidPresentationDefinitions(await this.mergedPayloads(), version)
  }

  public async getDcqlQuery(): Promise<DcqlQuery | undefined> {
    return await Dcql.findValidDcqlQuery(await this.mergedPayloads())
  }
}