import { ForbiddenError } from "@casl/ability";
import https from "https";
import jwt from "jsonwebtoken";
import { JwksClient } from "jwks-rsa";

import { IdentityAuthMethod, TIdentityJwtAuthsUpdate } from "@app/db/schemas";
import { TLicenseServiceFactory } from "@app/ee/services/license/license-service";
import { OrgPermissionActions, OrgPermissionSubjects } from "@app/ee/services/permission/org-permission";
import { TPermissionServiceFactory } from "@app/ee/services/permission/permission-service";
import { isAtLeastAsPrivileged } from "@app/lib/casl";
import { getConfig } from "@app/lib/config/env";
import { BadRequestError, ForbiddenRequestError, NotFoundError, UnauthorizedError } from "@app/lib/errors";
import { extractIPDetails, isValidIpOrCidr } from "@app/lib/ip";

import { ActorType, AuthTokenType } from "../auth/auth-type";
import { TIdentityOrgDALFactory } from "../identity/identity-org-dal";
import { TIdentityAccessTokenDALFactory } from "../identity-access-token/identity-access-token-dal";
import { TIdentityAccessTokenJwtPayload } from "../identity-access-token/identity-access-token-types";
import { TKmsServiceFactory } from "../kms/kms-service";
import { KmsDataKey } from "../kms/kms-types";
import { TIdentityJwtAuthDALFactory } from "./identity-jwt-auth-dal";
import { doesFieldValueMatchJwtPolicy } from "./identity-jwt-auth-fns";
import {
  JwtConfigurationType,
  TAttachJwtAuthDTO,
  TGetJwtAuthDTO,
  TLoginJwtAuthDTO,
  TRevokeJwtAuthDTO,
  TUpdateJwtAuthDTO
} from "./identity-jwt-auth-types";

type TIdentityJwtAuthServiceFactoryDep = {
  identityJwtAuthDAL: TIdentityJwtAuthDALFactory;
  identityOrgMembershipDAL: Pick<TIdentityOrgDALFactory, "findOne">;
  identityAccessTokenDAL: Pick<TIdentityAccessTokenDALFactory, "create" | "delete">;
  permissionService: Pick<TPermissionServiceFactory, "getOrgPermission">;
  licenseService: Pick<TLicenseServiceFactory, "getPlan">;
  kmsService: Pick<TKmsServiceFactory, "createCipherPairWithDataKey">;
};

export type TIdentityJwtAuthServiceFactory = ReturnType<typeof identityJwtAuthServiceFactory>;

export const identityJwtAuthServiceFactory = ({
  identityJwtAuthDAL,
  identityOrgMembershipDAL,
  permissionService,
  licenseService,
  identityAccessTokenDAL,
  kmsService
}: TIdentityJwtAuthServiceFactoryDep) => {
  const login = async ({ identityId, jwt: jwtValue }: TLoginJwtAuthDTO) => {
    const identityJwtAuth = await identityJwtAuthDAL.findOne({ identityId });
    if (!identityJwtAuth) {
      throw new NotFoundError({ message: "JWT auth method not found for identity, did you configure JWT auth?" });
    }

    const identityMembershipOrg = await identityOrgMembershipDAL.findOne({
      identityId: identityJwtAuth.identityId
    });
    if (!identityMembershipOrg) {
      throw new NotFoundError({
        message: `Identity organization membership for identity with ID '${identityJwtAuth.identityId}' not found`
      });
    }

    const { decryptor: orgDataKeyDecryptor } = await kmsService.createCipherPairWithDataKey({
      type: KmsDataKey.Organization,
      orgId: identityMembershipOrg.orgId
    });

    const decodedToken = jwt.decode(jwtValue, { complete: true });
    if (!decodedToken) {
      throw new UnauthorizedError({
        message: "Invalid JWT"
      });
    }

    let tokenData: Record<string, string | boolean | number> = {};

    if (identityJwtAuth.configurationType === JwtConfigurationType.JWKS) {
      const decryptedJwksCaCert = orgDataKeyDecryptor({
        cipherTextBlob: identityJwtAuth.encryptedJwksCaCert
      }).toString();
      const requestAgent = new https.Agent({ ca: decryptedJwksCaCert, rejectUnauthorized: !!decryptedJwksCaCert });
      const client = new JwksClient({
        jwksUri: identityJwtAuth.jwksUrl,
        requestAgent
      });

      const { kid } = decodedToken.header;
      const jwtSigningKey = await client.getSigningKey(kid);

      try {
        tokenData = jwt.verify(jwtValue, jwtSigningKey.getPublicKey()) as Record<string, string>;
      } catch (error) {
        if (error instanceof jwt.JsonWebTokenError) {
          throw new UnauthorizedError({
            message: `Access denied: ${error.message}`
          });
        }

        throw error;
      }
    } else {
      const decryptedPublicKeys = orgDataKeyDecryptor({ cipherTextBlob: identityJwtAuth.encryptedPublicKeys })
        .toString()
        .split(",");

      const errors: string[] = [];
      let isMatchAnyKey = false;
      for (const publicKey of decryptedPublicKeys) {
        try {
          tokenData = jwt.verify(jwtValue, publicKey) as Record<string, string>;
          isMatchAnyKey = true;
        } catch (error) {
          if (error instanceof jwt.JsonWebTokenError) {
            errors.push(error.message);
          }
        }
      }

      if (!isMatchAnyKey) {
        throw new UnauthorizedError({
          message: `Access denied: JWT verification failed with all keys. Errors - ${errors.join("; ")}`
        });
      }
    }

    if (identityJwtAuth.boundIssuer) {
      if (tokenData.iss !== identityJwtAuth.boundIssuer) {
        throw new ForbiddenRequestError({
          message: "Access denied: issuer mismatch"
        });
      }
    }

    if (identityJwtAuth.boundSubject) {
      if (!tokenData.sub) {
        throw new UnauthorizedError({
          message: "Access denied: token has no subject field"
        });
      }

      if (!doesFieldValueMatchJwtPolicy(tokenData.sub, identityJwtAuth.boundSubject)) {
        throw new ForbiddenRequestError({
          message: "Access denied: subject not allowed"
        });
      }
    }

    if (identityJwtAuth.boundAudiences) {
      if (!tokenData.aud) {
        throw new UnauthorizedError({
          message: "Access denied: token has no audience field"
        });
      }

      if (
        !identityJwtAuth.boundAudiences
          .split(", ")
          .some((policyValue) => doesFieldValueMatchJwtPolicy(tokenData.aud, policyValue))
      ) {
        throw new UnauthorizedError({
          message: "Access denied: token audience not allowed"
        });
      }
    }

    if (identityJwtAuth.boundClaims) {
      Object.keys(identityJwtAuth.boundClaims).forEach((claimKey) => {
        const claimValue = (identityJwtAuth.boundClaims as Record<string, string>)[claimKey];

        if (!tokenData[claimKey]) {
          throw new UnauthorizedError({
            message: `Access denied: token has no ${claimKey} field`
          });
        }

        // handle both single and multi-valued claims
        if (
          !claimValue.split(", ").some((claimEntry) => doesFieldValueMatchJwtPolicy(tokenData[claimKey], claimEntry))
        ) {
          throw new UnauthorizedError({
            message: `Access denied: claim mismatch for field ${claimKey}`
          });
        }
      });
    }

    const identityAccessToken = await identityJwtAuthDAL.transaction(async (tx) => {
      const newToken = await identityAccessTokenDAL.create(
        {
          identityId: identityJwtAuth.identityId,
          isAccessTokenRevoked: false,
          accessTokenTTL: identityJwtAuth.accessTokenTTL,
          accessTokenMaxTTL: identityJwtAuth.accessTokenMaxTTL,
          accessTokenNumUses: 0,
          accessTokenNumUsesLimit: identityJwtAuth.accessTokenNumUsesLimit,
          authMethod: IdentityAuthMethod.JWT_AUTH
        },
        tx
      );

      return newToken;
    });

    const appCfg = getConfig();
    const accessToken = jwt.sign(
      {
        identityId: identityJwtAuth.identityId,
        identityAccessTokenId: identityAccessToken.id,
        authTokenType: AuthTokenType.IDENTITY_ACCESS_TOKEN
      } as TIdentityAccessTokenJwtPayload,
      appCfg.AUTH_SECRET,
      // akhilmhdh: for non-expiry tokens you should not even set the value, including undefined. Even for undefined jsonwebtoken throws error
      Number(identityAccessToken.accessTokenTTL) === 0
        ? undefined
        : {
            expiresIn: Number(identityAccessToken.accessTokenTTL)
          }
    );

    return { accessToken, identityJwtAuth, identityAccessToken, identityMembershipOrg };
  };

  const attachJwtAuth = async ({
    identityId,
    configurationType,
    jwksUrl,
    jwksCaCert,
    publicKeys,
    boundIssuer,
    boundAudiences,
    boundClaims,
    boundSubject,
    accessTokenTTL,
    accessTokenMaxTTL,
    accessTokenNumUsesLimit,
    accessTokenTrustedIps,
    actorId,
    actorAuthMethod,
    actor,
    actorOrgId
  }: TAttachJwtAuthDTO) => {
    const identityMembershipOrg = await identityOrgMembershipDAL.findOne({ identityId });
    if (!identityMembershipOrg) {
      if (!identityMembershipOrg) throw new NotFoundError({ message: `Failed to find identity with ID ${identityId}` });
    }
    if (identityMembershipOrg.identity.authMethods.includes(IdentityAuthMethod.JWT_AUTH)) {
      throw new BadRequestError({
        message: "Failed to add JWT Auth to already configured identity"
      });
    }

    if (accessTokenMaxTTL > 0 && accessTokenTTL > accessTokenMaxTTL) {
      throw new BadRequestError({ message: "Access token TTL cannot be greater than max TTL" });
    }

    const { permission } = await permissionService.getOrgPermission(
      actor,
      actorId,
      identityMembershipOrg.orgId,
      actorAuthMethod,
      actorOrgId
    );

    ForbiddenError.from(permission).throwUnlessCan(OrgPermissionActions.Create, OrgPermissionSubjects.Identity);

    const plan = await licenseService.getPlan(identityMembershipOrg.orgId);
    const reformattedAccessTokenTrustedIps = accessTokenTrustedIps.map((accessTokenTrustedIp) => {
      if (
        !plan.ipAllowlisting &&
        accessTokenTrustedIp.ipAddress !== "0.0.0.0/0" &&
        accessTokenTrustedIp.ipAddress !== "::/0"
      )
        throw new BadRequestError({
          message:
            "Failed to add IP access range to access token due to plan restriction. Upgrade plan to add IP access range."
        });
      if (!isValidIpOrCidr(accessTokenTrustedIp.ipAddress))
        throw new BadRequestError({
          message: "The IP is not a valid IPv4, IPv6, or CIDR block"
        });
      return extractIPDetails(accessTokenTrustedIp.ipAddress);
    });

    const { encryptor: orgDataKeyEncryptor } = await kmsService.createCipherPairWithDataKey({
      type: KmsDataKey.Organization,
      orgId: actorOrgId
    });

    const { cipherTextBlob: encryptedJwksCaCert } = orgDataKeyEncryptor({
      plainText: Buffer.from(jwksCaCert)
    });

    const { cipherTextBlob: encryptedPublicKeys } = orgDataKeyEncryptor({
      plainText: Buffer.from(publicKeys.join(","))
    });

    const identityJwtAuth = await identityJwtAuthDAL.transaction(async (tx) => {
      const doc = await identityJwtAuthDAL.create(
        {
          identityId: identityMembershipOrg.identityId,
          configurationType,
          jwksUrl,
          encryptedJwksCaCert,
          encryptedPublicKeys,
          boundIssuer,
          boundAudiences,
          boundClaims,
          boundSubject,
          accessTokenMaxTTL,
          accessTokenTTL,
          accessTokenNumUsesLimit,
          accessTokenTrustedIps: JSON.stringify(reformattedAccessTokenTrustedIps)
        },
        tx
      );

      return doc;
    });
    return { ...identityJwtAuth, orgId: identityMembershipOrg.orgId, jwksCaCert, publicKeys };
  };

  const updateJwtAuth = async ({
    identityId,
    configurationType,
    jwksUrl,
    jwksCaCert,
    publicKeys,
    boundIssuer,
    boundAudiences,
    boundClaims,
    boundSubject,
    accessTokenTTL,
    accessTokenMaxTTL,
    accessTokenNumUsesLimit,
    accessTokenTrustedIps,
    actorId,
    actorAuthMethod,
    actor,
    actorOrgId
  }: TUpdateJwtAuthDTO) => {
    const identityMembershipOrg = await identityOrgMembershipDAL.findOne({ identityId });
    if (!identityMembershipOrg) throw new NotFoundError({ message: `Failed to find identity with ID ${identityId}` });

    if (!identityMembershipOrg.identity.authMethods.includes(IdentityAuthMethod.JWT_AUTH)) {
      throw new BadRequestError({
        message: "Failed to update JWT Auth"
      });
    }

    const identityJwtAuth = await identityJwtAuthDAL.findOne({ identityId });

    if (
      (accessTokenMaxTTL || identityJwtAuth.accessTokenMaxTTL) > 0 &&
      (accessTokenTTL || identityJwtAuth.accessTokenMaxTTL) > (accessTokenMaxTTL || identityJwtAuth.accessTokenMaxTTL)
    ) {
      throw new BadRequestError({ message: "Access token TTL cannot be greater than max TTL" });
    }

    const { permission } = await permissionService.getOrgPermission(
      actor,
      actorId,
      identityMembershipOrg.orgId,
      actorAuthMethod,
      actorOrgId
    );

    ForbiddenError.from(permission).throwUnlessCan(OrgPermissionActions.Edit, OrgPermissionSubjects.Identity);

    const plan = await licenseService.getPlan(identityMembershipOrg.orgId);
    const reformattedAccessTokenTrustedIps = accessTokenTrustedIps?.map((accessTokenTrustedIp) => {
      if (
        !plan.ipAllowlisting &&
        accessTokenTrustedIp.ipAddress !== "0.0.0.0/0" &&
        accessTokenTrustedIp.ipAddress !== "::/0"
      )
        throw new BadRequestError({
          message:
            "Failed to add IP access range to access token due to plan restriction. Upgrade plan to add IP access range."
        });
      if (!isValidIpOrCidr(accessTokenTrustedIp.ipAddress))
        throw new BadRequestError({
          message: "The IP is not a valid IPv4, IPv6, or CIDR block"
        });
      return extractIPDetails(accessTokenTrustedIp.ipAddress);
    });

    const updateQuery: TIdentityJwtAuthsUpdate = {
      boundIssuer,
      configurationType,
      jwksUrl,
      boundAudiences,
      boundClaims,
      boundSubject,
      accessTokenMaxTTL,
      accessTokenTTL,
      accessTokenNumUsesLimit,
      accessTokenTrustedIps: reformattedAccessTokenTrustedIps
        ? JSON.stringify(reformattedAccessTokenTrustedIps)
        : undefined
    };

    const { encryptor: orgDataKeyEncryptor, decryptor: orgDataKeyDecryptor } =
      await kmsService.createCipherPairWithDataKey({
        type: KmsDataKey.Organization,
        orgId: actorOrgId
      });

    if (jwksCaCert !== undefined) {
      const { cipherTextBlob: encryptedJwksCaCert } = orgDataKeyEncryptor({
        plainText: Buffer.from(jwksCaCert)
      });

      updateQuery.encryptedJwksCaCert = encryptedJwksCaCert;
    }

    if (publicKeys) {
      const { cipherTextBlob: encryptedPublicKeys } = orgDataKeyEncryptor({
        plainText: Buffer.from(publicKeys.join(","))
      });

      updateQuery.encryptedPublicKeys = encryptedPublicKeys;
    }

    const updatedJwtAuth = await identityJwtAuthDAL.updateById(identityJwtAuth.id, updateQuery);
    const decryptedJwksCaCert = orgDataKeyDecryptor({ cipherTextBlob: updatedJwtAuth.encryptedJwksCaCert }).toString();
    const decryptedPublicKeys = orgDataKeyDecryptor({ cipherTextBlob: updatedJwtAuth.encryptedPublicKeys })
      .toString()
      .split(",");

    return {
      ...updatedJwtAuth,
      orgId: identityMembershipOrg.orgId,
      jwksCaCert: decryptedJwksCaCert,
      publicKeys: decryptedPublicKeys
    };
  };

  const getJwtAuth = async ({ identityId, actorId, actor, actorAuthMethod, actorOrgId }: TGetJwtAuthDTO) => {
    const identityMembershipOrg = await identityOrgMembershipDAL.findOne({ identityId });
    if (!identityMembershipOrg) throw new NotFoundError({ message: `Failed to find identity with ID ${identityId}` });

    if (!identityMembershipOrg.identity.authMethods.includes(IdentityAuthMethod.JWT_AUTH)) {
      throw new BadRequestError({
        message: "The identity does not have JWT Auth attached"
      });
    }

    const { permission } = await permissionService.getOrgPermission(
      actor,
      actorId,
      identityMembershipOrg.orgId,
      actorAuthMethod,
      actorOrgId
    );

    ForbiddenError.from(permission).throwUnlessCan(OrgPermissionActions.Read, OrgPermissionSubjects.Identity);

    const identityJwtAuth = await identityJwtAuthDAL.findOne({ identityId });

    const { decryptor: orgDataKeyDecryptor } = await kmsService.createCipherPairWithDataKey({
      type: KmsDataKey.Organization,
      orgId: actorOrgId
    });

    const decryptedJwksCaCert = orgDataKeyDecryptor({ cipherTextBlob: identityJwtAuth.encryptedJwksCaCert }).toString();
    const decryptedPublicKeys = orgDataKeyDecryptor({ cipherTextBlob: identityJwtAuth.encryptedPublicKeys })
      .toString()
      .split(",");

    return {
      ...identityJwtAuth,
      orgId: identityMembershipOrg.orgId,
      jwksCaCert: decryptedJwksCaCert,
      publicKeys: decryptedPublicKeys
    };
  };

  const revokeJwtAuth = async ({ identityId, actorId, actor, actorAuthMethod, actorOrgId }: TRevokeJwtAuthDTO) => {
    const identityMembershipOrg = await identityOrgMembershipDAL.findOne({ identityId });
    if (!identityMembershipOrg) {
      throw new NotFoundError({ message: "Failed to find identity" });
    }

    if (!identityMembershipOrg.identity.authMethods.includes(IdentityAuthMethod.JWT_AUTH)) {
      throw new BadRequestError({
        message: "The identity does not have JWT auth"
      });
    }

    const { permission } = await permissionService.getOrgPermission(
      actor,
      actorId,
      identityMembershipOrg.orgId,
      actorAuthMethod,
      actorOrgId
    );

    ForbiddenError.from(permission).throwUnlessCan(OrgPermissionActions.Edit, OrgPermissionSubjects.Identity);

    const { permission: rolePermission } = await permissionService.getOrgPermission(
      ActorType.IDENTITY,
      identityMembershipOrg.identityId,
      identityMembershipOrg.orgId,
      actorAuthMethod,
      actorOrgId
    );

    if (!isAtLeastAsPrivileged(permission, rolePermission)) {
      throw new ForbiddenRequestError({
        message: "Failed to revoke JWT auth of identity with more privileged role"
      });
    }

    const revokedIdentityJwtAuth = await identityJwtAuthDAL.transaction(async (tx) => {
      const deletedJwtAuth = await identityJwtAuthDAL.delete({ identityId }, tx);
      await identityAccessTokenDAL.delete({ identityId, authMethod: IdentityAuthMethod.JWT_AUTH }, tx);

      return { ...deletedJwtAuth?.[0], orgId: identityMembershipOrg.orgId };
    });

    return revokedIdentityJwtAuth;
  };

  return {
    login,
    attachJwtAuth,
    updateJwtAuth,
    getJwtAuth,
    revokeJwtAuth
  };
};