import type { EBSIVerifiableAccreditationRecord } from "@cef-ebsi/vcdm1.1-accreditation-schema";
import type { EBSIVerifiableAttestation } from "@cef-ebsi/vcdm1.1-attestation-schema";

import {
  metadata as accreditationMetadata,
  schema as accreditationSchema,
} from "@cef-ebsi/vcdm1.1-accreditation-schema";
import {
  metadata as attestationMetadata,
  schema as attestationSchema,
} from "@cef-ebsi/vcdm1.1-attestation-schema";
import {
  metadata as statusList2021Metadata,
  schema as statusList2021Schema,
} from "@cef-ebsi/vcdm1.1-revocation-statuslist-schema";
import { AggregateAjvError } from "@segment/ajv-human-errors";
import addFormats from "ajv-formats";
import ajv2020 from "ajv/dist/2020.js";
import memoize from "memoize";

import type { EbsiEnvConfiguration } from "../types.ts";

import { JsonSchemaLoadingError } from "../errors/JsonSchemaLoadingError.ts";
import { JsonSchemaValidationError } from "../errors/JsonSchemaValidationError.ts";
import { ValidationError } from "../errors/ValidationError.ts";
import { loadSchema } from "../utils.ts";

/**
 * Returns a memoized Ajv instance
 * @param config - EBSI environment configuration
 * @param timeout - Axios requests timeout
 * @returns Ajv instance
 */
export const getAjvInstance = memoize(
  (config: EbsiEnvConfiguration, timeout?: number) => {
    // Configure Ajv
    const Ajv2020 = ajv2020.default;
    const ajv = new Ajv2020({
      allErrors: true,
      loadSchema: loadSchema(config, timeout),
      verbose: true,
    });

    // JSON Schema formats for Ajv
    addFormats.default(ajv);

    // Pre-register EBSI Verifiable Attestation schema
    ajv.addSchema(attestationSchema, attestationMetadata.id.base16);
    ajv.addSchema(
      attestationSchema,
      attestationMetadata.id.multibase_base58btc,
    );

    // Pre-register EBSI Verifiable Accreditation Record schema
    ajv.addSchema(accreditationSchema, accreditationMetadata.id.base16);
    ajv.addSchema(
      accreditationSchema,
      accreditationMetadata.id.multibase_base58btc,
    );

    // Pre-register EBSI StatusList2021Credential schema
    ajv.addSchema(statusList2021Schema, statusList2021Metadata.id.base16);
    ajv.addSchema(
      statusList2021Schema,
      statusList2021Metadata.id.multibase_base58btc,
    );

    return ajv;
  },
  {
    cacheKey: ([config, timeout]) =>
      `ajv-vc-${JSON.stringify(config)}${(timeout ?? "undefined").toString()}`,
  },
);

/**
 * Validates that the given value is an EbsiVerifiableAccreditation object.
 * @param value - Credential payload
 * @param config - EBSI environment configuration
 * @param timeout - Axios requests timeout. Default: 15 seconds
 */
export function validateEbsiVerifiableAccreditation(
  value: unknown,
  config: EbsiEnvConfiguration,
  timeout?: number,
): asserts value is EBSIVerifiableAccreditationRecord {
  if (typeof value !== "object") {
    throw new ValidationError(
      "Invalid EBSI Verifiable Accreditation. The value must be an object.",
    );
  }

  const ajv = getAjvInstance(config, timeout);

  const validate = ajv.getSchema(accreditationMetadata.id.base16);

  if (!validate) {
    throw new JsonSchemaLoadingError(
      "Unable to get EBSI Verifiable Accreditation schema",
    );
  }

  const valid = validate(value);

  if (!valid && validate.errors) {
    const errors = new AggregateAjvError(validate.errors, {
      fieldLabels: "jsonPointer",
    });
    throw new JsonSchemaValidationError(
      `Invalid EBSI Verifiable Accreditation. ${errors.message}`,
      validate.errors,
    );
  }
}

/**
 * Validates that the given value is an EBSIVerifiableAttestation object.
 * @param value - Credential payload
 * @param config - EBSI environment configuration
 * @param timeout - Axios requests timeout. Default: 15 seconds
 */
export function validateEbsiVerifiableAttestation(
  value: unknown,
  config: EbsiEnvConfiguration,
  timeout?: number,
): asserts value is EBSIVerifiableAttestation {
  if (typeof value !== "object") {
    throw new ValidationError(
      "Invalid EBSI Verifiable Attestation. The value must be an object.",
    );
  }

  const ajv = getAjvInstance(config, timeout);

  const validate = ajv.getSchema(attestationMetadata.id.base16);

  if (!validate) {
    throw new JsonSchemaLoadingError("Unable to get EBSI VA schema");
  }

  const valid = validate(value);

  if (!valid && validate.errors) {
    const errors = new AggregateAjvError(validate.errors, {
      fieldLabels: "jsonPointer",
    });
    throw new JsonSchemaValidationError(
      `Invalid EBSI Verifiable Attestation. ${errors.message}`,
      validate.errors,
    );
  }
}