import { expect } from 'chai'
import { nativeTheme, systemPreferences } from 'electron'
import * as os from 'os'
import * as semver from 'semver'

import { delay, ifdescribe } from './spec-helpers'
import { emittedOnce } from './events-helpers';

describe('nativeTheme module', () => {
  describe('nativeTheme.shouldUseDarkColors', () => {
    it('returns a boolean', () => {
      expect(nativeTheme.shouldUseDarkColors).to.be.a('boolean')
    })
  })

  describe('nativeTheme.themeSource', () => {
    afterEach(async () => {
      nativeTheme.themeSource = 'system'
      // Wait for any pending events to emit
      await delay(20)
    })

    it('is system by default', () => {
      expect(nativeTheme.themeSource).to.equal('system')
    })

    it('should override the value of shouldUseDarkColors', () => {
      nativeTheme.themeSource = 'dark'
      expect(nativeTheme.shouldUseDarkColors).to.equal(true)
      nativeTheme.themeSource = 'light'
      expect(nativeTheme.shouldUseDarkColors).to.equal(false)
    })

    it('should emit the "updated" event when it is set and the resulting "shouldUseDarkColors" value changes', async () => {
      let updatedEmitted = emittedOnce(nativeTheme, 'updated')
      nativeTheme.themeSource = 'dark'
      await updatedEmitted
      updatedEmitted = emittedOnce(nativeTheme, 'updated')
      nativeTheme.themeSource = 'light'
      await updatedEmitted
    })

    it('should not emit the "updated" event when it is set and the resulting "shouldUseDarkColors" value is the same', async () => {
      nativeTheme.themeSource = 'dark'
      // Wait a few ticks to allow an async events to flush
      await delay(20)
      let called = false
      nativeTheme.once('updated', () => {
        called = true
      })
      nativeTheme.themeSource = 'dark'
      // Wait a few ticks to allow an async events to flush
      await delay(20)
      expect(called).to.equal(false)
    })

    ifdescribe(process.platform === 'darwin' && semver.gte(os.release(), '18.0.0'))('on macOS 10.14', () => {
      it('should update appLevelAppearance when set', () => {
        nativeTheme.themeSource = 'dark'
        expect(systemPreferences.appLevelAppearance).to.equal('dark')
        nativeTheme.themeSource = 'light'
        expect(systemPreferences.appLevelAppearance).to.equal('light')
      })
    })
  })

  describe('nativeTheme.shouldUseInvertedColorScheme', () => {
    it('returns a boolean', () => {
      expect(nativeTheme.shouldUseInvertedColorScheme).to.be.a('boolean')
    })
  })

  describe('nativeTheme.shouldUseHighContrastColors', () => {
    it('returns a boolean', () => {
      expect(nativeTheme.shouldUseHighContrastColors).to.be.a('boolean')
    })
  })
})