const expect = require("chai").expect;
const { CloudEvent } = require("../index.js");
const {
  MIME_JSON,
  ENCODING_BASE64,
  SPEC_V03,
  BINARY
} = require("../lib/bindings/http/constants.js");
const ValidationError = require("../lib/bindings/http/validation/validation_error.js");

const id = "97699ec2-a8d9-47c1-bfa0-ff7aa526f838";
const type = "com.github.pull.create";
const source = "urn:event:from:myapi/resourse/123";
const time = new Date();
const schemaURL = "http://example.com/registry/myschema.json";
const data = {
  much: "wow"
};
const subject = "subject-x0";

const cloudevent = new CloudEvent({
  specversion: SPEC_V03,
  id,
  source,
  type,
  subject,
  time,
  data,
  schemaURL,
  dataContentType: MIME_JSON
});

describe("CloudEvents Spec v0.3", () => {
  describe("REQUIRED Attributes", () => {
    it("Should have 'id'", () => {
      expect(cloudevent.id).to.equal(id);
    });

    it("Should have 'source'", () => {
      expect(cloudevent.source).to.equal(source);
    });

    it("Should have 'specversion'", () => {
      expect(cloudevent.specversion).to.equal(SPEC_V03);
    });

    it("Should have 'type'", () => {
      expect(cloudevent.type).to.equal(type);
    });
  });

  describe("OPTIONAL Attributes", () => {
    it("Should have 'datacontentencoding'", () => {
      cloudevent.dataContentEncoding = ENCODING_BASE64;
      expect(cloudevent.spec.payload.datacontentencoding)
        .to.equal(ENCODING_BASE64);
      delete cloudevent.spec.payload.datacontentencoding;
    });

    it("Should have 'datacontenttype'", () => {
      expect(cloudevent.dataContentType).to.equal(MIME_JSON);
    });

    it("Should have 'schemaurl'", () => {
      expect(cloudevent.schemaURL).to.equal(schemaURL);
    });

    it("Should have 'subject'", () => {
      expect(cloudevent.subject).to.equal(subject);
    });

    it("Should have 'time'", () => {
      expect(cloudevent.time).to.equal(time.toISOString());
    });

    it("Should have 'data'", () => {
      expect(cloudevent.data).to.deep.equal(data);
    });

    it("Should have the 'extension1'", () => {
      cloudevent.addExtension("extension1", "value1");
      expect(cloudevent.spec.payload.extension1)
        .to.equal("value1");
    });

    it("should throw an error when use a reserved name as extension", () => {
      expect(cloudevent.addExtension.bind(cloudevent, "id"))
        .to.throw(ValidationError, "Reserved attribute name: 'id'");
    });
  });

  describe("The Constraints check", () => {
    describe("'id'", () => {
      it("should throw an error when is absent", () => {
        delete cloudevent.spec.payload.id;
        expect(cloudevent.format.bind(cloudevent))
          .to.throw(ValidationError, "invalid payload");
        cloudevent.spec.payload.id = id;
      });

      it("should throw an error when is empty", () => {
        cloudevent.spec.payload.id = "";
        expect(cloudevent.format.bind(cloudevent))
          .to.throw(ValidationError, "invalid payload");
        cloudevent.spec.payload.id = id;
      });
    });

    describe("'source'", () => {
      it("should throw an error when is absent", () => {
        delete cloudevent.spec.payload.source;
        expect(cloudevent.format.bind(cloudevent))
          .to.throw(ValidationError, "invalid payload");
        cloudevent.spec.payload.source = source;
      });
    });

    describe("'specversion'", () => {
      it("should throw an error when is absent", () => {
        delete cloudevent.spec.payload.specversion;
        expect(cloudevent.format.bind(cloudevent))
          .to.throw(ValidationError, "invalid payload");
        cloudevent.spec.payload.specversion = SPEC_V03;
      });

      it("should throw an error when is empty", () => {
        cloudevent.spec.payload.specversion = "";
        expect(cloudevent.format.bind(cloudevent))
          .to.throw(ValidationError, "invalid payload");
        cloudevent.spec.payload.specversion = SPEC_V03;
      });
    });

    describe("'type'", () => {
      it("should throw an error when is absent", () => {
        delete cloudevent.spec.payload.type;
        expect(cloudevent.format.bind(cloudevent))
          .to.throw(ValidationError, "invalid payload");
        cloudevent.spec.payload.type = type;
      });

      it("should throw an error when is an empty string", () => {
        cloudevent.type = "";
        expect(cloudevent.format.bind(cloudevent))
          .to.throw(ValidationError, "invalid payload");
        cloudevent.type = type;
      });

      it("must be a non-empty string", () => {
        cloudevent.type = type;
        expect(cloudevent.spec.payload.type).to.equal(type);
      });
    });

    describe("'datacontentencoding'", () => {
      it("should throw an error when is a unsupported encoding", () => {
        cloudevent.data = "Y2xvdWRldmVudHMK";
        cloudevent.dataContentEncoding = BINARY;
        expect(cloudevent.format.bind(cloudevent))
          .to.throw(ValidationError, "invalid payload");
        delete cloudevent.spec.payload.datacontentencoding;
        cloudevent.data = data;
      });

      it("should throw an error when 'data' does not carry base64",
        () => {
          cloudevent.data = "no base 64 value";
          cloudevent.dataContentEncoding = ENCODING_BASE64;
          cloudevent.dataContentType = "text/plain";

          expect(cloudevent.format.bind(cloudevent))
            .to.throw(ValidationError, "invalid payload");

          delete cloudevent.spec.payload.datacontentencoding;
          cloudevent.data = data;
        });

      it("should accept when 'data' is a string", () => {
        cloudevent.data = "Y2xvdWRldmVudHMK";
        cloudevent.dataContentEncoding = ENCODING_BASE64;
        expect(cloudevent.format()).to.have.property("datacontentencoding");
        delete cloudevent.spec.payload.datacontentencoding;
        cloudevent.data = data;
      });
    });

    describe("'data'", () => {
      it("should maintain the type of data when no data content type", () => {
        delete cloudevent.spec.payload.datacontenttype;
        cloudevent.data = JSON.stringify(data);

        expect(typeof cloudevent.data).to.equal("string");
        cloudevent.dataContentType = MIME_JSON;
      });

      it("should convert data with stringified json to a json object", () => {
        cloudevent.dataContentType = MIME_JSON;
        cloudevent.data = JSON.stringify(data);
        expect(cloudevent.data).to.deep.equal(data);
      });
    });

    describe("'subject'", () => {
      it("should throw an error when is an empty string", () => {
        cloudevent.subject = "";
        expect(cloudevent.format.bind(cloudevent))
          .to.throw(ValidationError, "invalid payload");
        cloudevent.subject = subject;
      });
    });

    describe("'time'", () => {
      it("must adhere to the format specified in RFC 3339", () => {
        expect(cloudevent.format().time).to.equal(time.toISOString());
      });
    });
  });
});