import EmberObject from '@ember/object';
import { assign } from '@ember/polyfills';
import { module, test } from 'qunit';
import sinon from 'sinon';
import Pretender from 'pretender';
import AllocationStatsTracker, { stats } from 'nomad-ui/utils/classes/allocation-stats-tracker';
import fetch from 'nomad-ui/utils/fetch';
import statsTrackerFrameMissingBehavior from './behaviors/stats-tracker-frame-missing';

import { settled } from '@ember/test-helpers';

module('Unit | Util | AllocationStatsTracker', function() {
  const refDate = Date.now() * 1000000;
  const makeDate = ts => new Date(ts / 1000000);

  const MockAllocation = overrides =>
    assign(
      {
        id: 'some-identifier',
        taskGroup: {
          reservedCPU: 200,
          reservedMemory: 512,
          tasks: [
            {
              name: 'service',
              reservedCPU: 100,
              reservedMemory: 256,
            },
            {
              name: 'log-shipper',
              reservedCPU: 50,
              reservedMemory: 128,
            },
            {
              name: 'sidecar',
              reservedCPU: 50,
              reservedMemory: 128,
            },
          ],
        },
      },
      overrides
    );

  const mockFrame = step => ({
    ResourceUsage: {
      CpuStats: {
        TotalTicks: step + 100,
      },
      MemoryStats: {
        RSS: (step + 400) * 1024 * 1024,
      },
    },
    Tasks: {
      service: {
        ResourceUsage: {
          CpuStats: {
            TotalTicks: step + 50,
          },
          MemoryStats: {
            RSS: (step + 100) * 1024 * 1024,
          },
        },
        Timestamp: refDate + step,
      },
      'log-shipper': {
        ResourceUsage: {
          CpuStats: {
            TotalTicks: step + 25,
          },
          MemoryStats: {
            RSS: (step + 50) * 1024 * 1024,
          },
        },
        Timestamp: refDate + step * 10,
      },
      sidecar: {
        ResourceUsage: {
          CpuStats: {
            TotalTicks: step + 26,
          },
          MemoryStats: {
            RSS: (step + 51) * 1024 * 1024,
          },
        },
        Timestamp: refDate + step * 100,
      },
    },
    Timestamp: refDate + step * 1000,
  });

  test('the AllocationStatsTracker constructor expects a fetch definition and an allocation', async function(assert) {
    const tracker = AllocationStatsTracker.create();
    assert.throws(
      () => {
        tracker.fetch();
      },
      /StatsTrackers need a fetch method/,
      'Polling does not work without a fetch method provided'
    );
  });

  test('the url property is computed based off the allocation id', async function(assert) {
    const allocation = MockAllocation();
    const tracker = AllocationStatsTracker.create({ fetch, allocation });

    assert.equal(
      tracker.get('url'),
      `/v1/client/allocation/${allocation.id}/stats`,
      'Url is derived from the allocation id'
    );
  });

  test('reservedCPU and reservedMemory properties come from the allocation', async function(assert) {
    const allocation = MockAllocation();
    const tracker = AllocationStatsTracker.create({ fetch, allocation });

    assert.equal(
      tracker.get('reservedCPU'),
      allocation.taskGroup.reservedCPU,
      'reservedCPU comes from the allocation task group'
    );
    assert.equal(
      tracker.get('reservedMemory'),
      allocation.taskGroup.reservedMemory,
      'reservedMemory comes from the allocation task group'
    );
  });

  test('the tasks list comes from the allocation', async function(assert) {
    const allocation = MockAllocation();
    const tracker = AllocationStatsTracker.create({ fetch, allocation });

    assert.equal(
      tracker.get('tasks.length'),
      allocation.taskGroup.tasks.length,
      'tasks matches lengths with the allocation task group'
    );
    allocation.taskGroup.tasks.forEach(task => {
      const trackerTask = tracker.get('tasks').findBy('task', task.name);
      assert.equal(trackerTask.reservedCPU, task.reservedCPU, `CPU matches for task ${task.name}`);
      assert.equal(
        trackerTask.reservedMemory,
        task.reservedMemory,
        `Memory matches for task ${task.name}`
      );
    });
  });

  test('poll results in requesting the url and calling append with the resulting JSON', async function(assert) {
    const allocation = MockAllocation();
    const tracker = AllocationStatsTracker.create({ fetch, allocation, append: sinon.spy() });
    const mockFrame = {
      Some: {
        data: ['goes', 'here'],
        twelve: 12,
      },
    };

    const server = new Pretender(function() {
      this.get('/v1/client/allocation/:id/stats', () => [200, {}, JSON.stringify(mockFrame)]);
    });

    tracker.get('poll').perform();

    assert.equal(server.handledRequests.length, 1, 'Only one request was made');
    assert.equal(
      server.handledRequests[0].url,
      `/v1/client/allocation/${allocation.id}/stats`,
      'The correct URL was requested'
    );

    await settled();
    assert.ok(
      tracker.append.calledWith(mockFrame),
      'The JSON response was passed onto append as a POJO'
    );

    server.shutdown();
  });

  test('append appropriately maps a data frame to the tracked stats for cpu and memory for the allocation as well as individual tasks', async function(assert) {
    const allocation = MockAllocation();
    const tracker = AllocationStatsTracker.create({ fetch, allocation });

    assert.deepEqual(tracker.get('cpu'), [], 'No tracked cpu yet');
    assert.deepEqual(tracker.get('memory'), [], 'No tracked memory yet');

    assert.deepEqual(
      tracker.get('tasks'),
      [
        { task: 'service', reservedCPU: 100, reservedMemory: 256, cpu: [], memory: [] },
        { task: 'log-shipper', reservedCPU: 50, reservedMemory: 128, cpu: [], memory: [] },
        { task: 'sidecar', reservedCPU: 50, reservedMemory: 128, cpu: [], memory: [] },
      ],
      'tasks represents the tasks for the allocation with no stats yet'
    );

    tracker.append(mockFrame(1));

    assert.deepEqual(
      tracker.get('cpu'),
      [{ timestamp: makeDate(refDate + 1000), used: 101, percent: 101 / 200 }],
      'One frame of cpu'
    );
    assert.deepEqual(
      tracker.get('memory'),
      [
        {
          timestamp: makeDate(refDate + 1000),
          used: 401 * 1024 * 1024,
          percent: 401 / 512,
        },
      ],
      'One frame of memory'
    );

    assert.deepEqual(
      tracker.get('tasks'),
      [
        {
          task: 'service',
          reservedCPU: 100,
          reservedMemory: 256,
          cpu: [{ timestamp: makeDate(refDate + 1), used: 51, percent: 51 / 100 }],
          memory: [
            {
              timestamp: makeDate(refDate + 1),
              used: 101 * 1024 * 1024,
              percent: 101 / 256,
            },
          ],
        },
        {
          task: 'log-shipper',
          reservedCPU: 50,
          reservedMemory: 128,
          cpu: [{ timestamp: makeDate(refDate + 10), used: 26, percent: 26 / 50 }],
          memory: [
            {
              timestamp: makeDate(refDate + 10),
              used: 51 * 1024 * 1024,
              percent: 51 / 128,
            },
          ],
        },
        {
          task: 'sidecar',
          reservedCPU: 50,
          reservedMemory: 128,
          cpu: [{ timestamp: makeDate(refDate + 100), used: 27, percent: 27 / 50 }],
          memory: [
            {
              timestamp: makeDate(refDate + 100),
              used: 52 * 1024 * 1024,
              percent: 52 / 128,
            },
          ],
        },
      ],
      'tasks represents the tasks for the allocation, each with one frame of stats'
    );

    tracker.append(mockFrame(2));

    assert.deepEqual(
      tracker.get('cpu'),
      [
        { timestamp: makeDate(refDate + 1000), used: 101, percent: 101 / 200 },
        { timestamp: makeDate(refDate + 2000), used: 102, percent: 102 / 200 },
      ],
      'Two frames of cpu'
    );
    assert.deepEqual(
      tracker.get('memory'),
      [
        { timestamp: makeDate(refDate + 1000), used: 401 * 1024 * 1024, percent: 401 / 512 },
        { timestamp: makeDate(refDate + 2000), used: 402 * 1024 * 1024, percent: 402 / 512 },
      ],
      'Two frames of memory'
    );

    assert.deepEqual(
      tracker.get('tasks'),
      [
        {
          task: 'service',
          reservedCPU: 100,
          reservedMemory: 256,
          cpu: [
            { timestamp: makeDate(refDate + 1), used: 51, percent: 51 / 100 },
            { timestamp: makeDate(refDate + 2), used: 52, percent: 52 / 100 },
          ],
          memory: [
            { timestamp: makeDate(refDate + 1), used: 101 * 1024 * 1024, percent: 101 / 256 },
            { timestamp: makeDate(refDate + 2), used: 102 * 1024 * 1024, percent: 102 / 256 },
          ],
        },
        {
          task: 'log-shipper',
          reservedCPU: 50,
          reservedMemory: 128,
          cpu: [
            { timestamp: makeDate(refDate + 10), used: 26, percent: 26 / 50 },
            { timestamp: makeDate(refDate + 20), used: 27, percent: 27 / 50 },
          ],
          memory: [
            { timestamp: makeDate(refDate + 10), used: 51 * 1024 * 1024, percent: 51 / 128 },
            { timestamp: makeDate(refDate + 20), used: 52 * 1024 * 1024, percent: 52 / 128 },
          ],
        },
        {
          task: 'sidecar',
          reservedCPU: 50,
          reservedMemory: 128,
          cpu: [
            { timestamp: makeDate(refDate + 100), used: 27, percent: 27 / 50 },
            { timestamp: makeDate(refDate + 200), used: 28, percent: 28 / 50 },
          ],
          memory: [
            { timestamp: makeDate(refDate + 100), used: 52 * 1024 * 1024, percent: 52 / 128 },
            { timestamp: makeDate(refDate + 200), used: 53 * 1024 * 1024, percent: 53 / 128 },
          ],
        },
      ],
      'tasks represents the tasks for the allocation, each with two frames of stats'
    );
  });

  test('each stat list has maxLength equal to bufferSize', async function(assert) {
    const allocation = MockAllocation();
    const bufferSize = 10;
    const tracker = AllocationStatsTracker.create({ fetch, allocation, bufferSize });

    for (let i = 1; i <= 20; i++) {
      tracker.append(mockFrame(i));
    }

    assert.equal(
      tracker.get('cpu.length'),
      bufferSize,
      `20 calls to append, only ${bufferSize} frames in the stats array`
    );
    assert.equal(
      tracker.get('memory.length'),
      bufferSize,
      `20 calls to append, only ${bufferSize} frames in the stats array`
    );

    assert.equal(
      +tracker.get('cpu')[0].timestamp,
      +makeDate(refDate + 11000),
      'Old frames are removed in favor of newer ones'
    );
    assert.equal(
      +tracker.get('memory')[0].timestamp,
      +makeDate(refDate + 11000),
      'Old frames are removed in favor of newer ones'
    );

    tracker.get('tasks').forEach(task => {
      assert.equal(
        task.cpu.length,
        bufferSize,
        `20 calls to append, only ${bufferSize} frames in the stats array`
      );
      assert.equal(
        task.memory.length,
        bufferSize,
        `20 calls to append, only ${bufferSize} frames in the stats array`
      );
    });

    assert.equal(
      +tracker.get('tasks').findBy('task', 'service').cpu[0].timestamp,
      +makeDate(refDate + 11),
      'Old frames are removed in favor of newer ones'
    );
    assert.equal(
      +tracker.get('tasks').findBy('task', 'service').memory[0].timestamp,
      +makeDate(refDate + 11),
      'Old frames are removed in favor of newer ones'
    );

    assert.equal(
      +tracker.get('tasks').findBy('task', 'log-shipper').cpu[0].timestamp,
      +makeDate(refDate + 110),
      'Old frames are removed in favor of newer ones'
    );
    assert.equal(
      +tracker.get('tasks').findBy('task', 'log-shipper').memory[0].timestamp,
      +makeDate(refDate + 110),
      'Old frames are removed in favor of newer ones'
    );

    assert.equal(
      +tracker.get('tasks').findBy('task', 'sidecar').cpu[0].timestamp,
      +makeDate(refDate + 1100),
      'Old frames are removed in favor of newer ones'
    );
    assert.equal(
      +tracker.get('tasks').findBy('task', 'sidecar').memory[0].timestamp,
      +makeDate(refDate + 1100),
      'Old frames are removed in favor of newer ones'
    );
  });

  test('the stats computed property macro constructs an AllocationStatsTracker based on an allocationProp and a fetch definition', async function(assert) {
    const allocation = MockAllocation();
    const fetchSpy = sinon.spy();

    const SomeClass = EmberObject.extend({
      stats: stats('alloc', function() {
        return () => fetchSpy(this);
      }),
    });
    const someObject = SomeClass.create({
      alloc: allocation,
    });

    assert.equal(
      someObject.get('stats.url'),
      `/v1/client/allocation/${allocation.id}/stats`,
      'stats computed property macro creates an AllocationStatsTracker'
    );

    someObject.get('stats').fetch();

    assert.ok(
      fetchSpy.calledWith(someObject),
      'the fetch factory passed into the macro gets called to assign a bound version of fetch to the AllocationStatsTracker instance'
    );
  });

  test('changing the value of the allocationProp constructs a new AllocationStatsTracker', async function(assert) {
    const alloc1 = MockAllocation();
    const alloc2 = MockAllocation();
    const SomeClass = EmberObject.extend({
      stats: stats('alloc', () => fetch),
    });

    const someObject = SomeClass.create({
      alloc: alloc1,
    });

    const stats1 = someObject.get('stats');

    someObject.set('alloc', alloc2);
    const stats2 = someObject.get('stats');

    assert.notOk(
      stats1 === stats2,
      'Changing the value of alloc results in creating a new AllocationStatsTracker instance'
    );
  });

  statsTrackerFrameMissingBehavior({
    resourceName: 'allocation',
    ResourceConstructor: MockAllocation,
    TrackerConstructor: AllocationStatsTracker,
    mockFrame,
    compileResources(frame) {
      const timestamp = makeDate(frame.Timestamp);
      const cpu = frame.ResourceUsage.CpuStats.TotalTicks;
      const memory = frame.ResourceUsage.MemoryStats.RSS;
      return [
        {
          timestamp,
          used: cpu,
          percent: cpu / 200,
        },
        {
          timestamp,
          used: memory,
          percent: memory / 1024 / 1024 / 512,
        },
      ];
    },
  });
});