/* @flow */
/*eslint-env browser,jasmine */

// returns a random element of o
// works on Object, and Array
function getRandom (o) {
  if (o instanceof Array) {
    return o[Math.floor(Math.random() * o.length)];
  } else if (o.constructor === Object) {
    var ks = [];
    for (var key in o) {
      keys.push(key);
    }
    return o[getRandom(ks)];
  }
}
function getRandomNumber(n) {
  if (n == null) {
    n = 9999;
  }
  return Math.floor(Math.random() * n);
}
var keys = ["a", "b", "c", "d", "e", "f", 1, 2, 3, 4, 5, 6];
var numberOfTests = 500;

function applyRandomTransactions (users, transactions) {
  function* randomTransaction (root) {
    var f = getRandom(transactions);
    yield* f(root);
  }
  for(var i = 0; i < numberOfTests; i++) {
    var r = getRandomNumber(100);
    if (r >= 50) {
      users[0].connector.flushOne();
    } else {
      getRandom(users).transact(randomTransaction);
    }
  }
}

function compareAllUsers(users){
  var s1, s2;
  function* t1(){
    s1 = yield* this.getStateSet();
  }
  function* t2(){
    s2 = yield* this.getStateSet();
  }
  users[0].connector.flushAll();
  for (var uid = 0; uid + 1 < users.length; uid++) {
    var u1 = users[uid];
    var u2 = users[uid + 1];
    u1.transact(t1);
    u2.transact(t2);
    expect(s1).toEqual(s2);
    var db1 = u1.db.os;
    var db2 = u2.db.os;
    for (var key in db1) {
      expect(db1[key]).toEqual(db2[key]);
    }
  }
}

describe("Yjs", function(){
  jasmine.DEFAULT_TIMEOUT_INTERVAL = 500;
  beforeEach(function(){
    this.users = [];
    for (var i = 0; i < 5; i++) {
      this.users.push(new Y({
        db: {
          name: "Memory"
        },
        connector: {
          name: "Test",
          debug: false
        }
      }));
    }
  });
  afterEach(function(){
    for (var y of this.users) {
      y.destroy();
    }
    this.users = [];
  });

  describe("Basic tests", function(){
    it("There is an initial Map type", function(){
      var y = this.users[0];
      y.transact(function*(root){
        expect(root).not.toBeUndefined();
      });
    });
    it("Basic get&set of Map property (converge via sync)", function(){
      var y = this.users[0];
      y.transact(function*(root){
        yield* root.val("stuff", "stuffy");
        expect(yield* root.val("stuff")).toEqual("stuffy");
      });

      y.connector.flushAll();

      var transaction = function*(root){
        expect(yield* root.val("stuff")).toEqual("stuffy");
      };
      for (var key in this.users) {
        var u = this.users[key];
        u.transact(transaction);
      }
    });
    it("Basic get&set of Map property (converge via update)", function(){
      var y = this.users[0];
      y.connector.flushAll();
      y.transact(function*(root){
        yield* root.val("stuff", "stuffy");
        expect(yield* root.val("stuff")).toEqual("stuffy");
      });

      var transaction = function*(root){
        expect(yield* root.val("stuff")).toEqual("stuffy");
      };
      y.connector.flushAll();

      for (var key in this.users) {
        var u = this.users[key];
        u.transact(transaction);
      }
    });
    it("Basic get&set of Map property (handle conflict)", function(){
      var y = this.users[0];
      y.connector.flushAll();
      this.users[0].transact(function*(root){
        yield* root.val("stuff", "c0");
      });
      this.users[1].transact(function*(root){
        yield* root.val("stuff", "c1");
      });

      var transaction = function*(root){
        expect(yield* root.val("stuff")).toEqual("c0");
      };
      y.connector.flushAll();

      for (var key in this.users) {
        var u = this.users[key];
        u.transact(transaction);
      }
    });
    it("Basic get&set of Map property (handle three conflicts)", function(){
      var y = this.users[0];
      y.connector.flushAll();
      this.users[0].transact(function*(root){
        yield* root.val("stuff", "c0");
      });
      this.users[1].transact(function*(root){
        yield* root.val("stuff", "c1");
      });
      this.users[2].transact(function*(root){
        yield* root.val("stuff", "c2");
      });
      this.users[3].transact(function*(root){
        yield* root.val("stuff", "c3");
      });
      y.connector.flushAll();
      var transaction = function*(root){
        expect(yield* root.val("stuff")).toEqual("c0");
      };

      for (var key in this.users) {
        var u = this.users[key];
        u.transact(transaction);
      }
    });
  });
  it("can create a List type", function(){
    var y = this.users[0];
    y.transact(function*(root){
      var list = yield* Y.List();
      yield* root.val("list", list);
      yield* list.insert(0, [1, 2, 3, 4]);
      expect(yield* root.val("list")).not.toBeUndefined();
    });
    y.connector.flushAll();
    function* transaction (root) {
      var list = yield* root.val("list");
      expect(yield* list.val()).toEqual([1, 2, 3, 4]);
    }
    for (var u of this.users) {
      u.transact(transaction);
    }
  });
  describe("Map random tests", function(){
    var randomMapTransactions = [
      function* set (map) {
        yield* map.val("getRandom(keys)", getRandomNumber());
      }
    ];
    it(`succeed after ${numberOfTests} actions with flush before transactions`, function(){
      this.users[0].connector.flushAll(); // TODO: Remove!!
      applyRandomTransactions(this.users, randomMapTransactions);
      compareAllUsers(this.users);
    });
    it(`succeed after ${numberOfTests} actions without flush before transactions`, function(){
      applyRandomTransactions(this.users, randomMapTransactions);
      compareAllUsers(this.users);
    });
  });
  describe("Map debug tests", function(){
    beforeEach(function(){
      this.u1 = this.users[0];
      this.u2 = this.users[1];
      this.u3 = this.users[2];
    });
    it("concurrent insertions #1", function(){
      this.u1.transact(function*(root){
        var op = {
          content: 1,
          left: null,
          right: null,
          parent: root._model,
          parentSub: "a"
        };
        Struct.Insert.create.call(this, op);
      });
      compareAllUsers(this.users);
    });
  });
});