package com.fireworksdk.bridge.components.videofeed

import com.fireworksdk.bridge.components.videofeed.FWAutosizingState.Pass
import org.junit.Assert.assertEquals
import org.junit.Assert.assertNull
import org.junit.Test

class FWAutosizingStateTest {
  private val state = FWAutosizingState()

  private fun settle(height: Int = 900, width: Int = 400) {
    repeat(2) {
      assertEquals(Pass.FORCE, state.nextPass(width, false))
      state.didMeasure(height)
    }
    assertEquals(Pass.NORMAL, state.nextPass(width, false))
  }

  @Test fun zeroWidthDefersTheInitialMeasurement() {
    assertEquals(Pass.NONE, state.nextPass(0, false))
    settle()
  }

  @Test fun stableContentKeepsNormalLayoutWithoutForcingTheSubtree() {
    settle()
    repeat(120) { assertEquals(Pass.NORMAL, state.nextPass(400, false)) }
  }

  @Test fun explicitInvalidationRequiresConvergenceWithinTheNewRound() {
    settle()
    state.invalidate()
    settle()
  }

  @Test fun widthChangeMeasuresAgainEvenWithoutALayoutRequest() {
    settle()
    settle(height = 1200, width = 300)
  }

  @Test fun asyncLayoutRequestAfterIdleStartsANewRound() {
    settle()
    assertEquals(Pass.FORCE, state.nextPass(400, true))
    state.didMeasure(1500)
    assertEquals(Pass.FORCE, state.nextPass(400, false))
    state.didMeasure(1500)
    assertEquals(Pass.NORMAL, state.nextPass(400, false))
  }

  @Test fun repeatedLayoutRequestsCannotContinuouslyRearmForcedPasses() {
    repeat(8) { index ->
      assertEquals(Pass.FORCE, state.nextPass(400, true))
      state.didMeasure(900 + index)
    }
    repeat(20) { index ->
      assertEquals(Pass.NORMAL, state.nextPass(400, true))
      state.didMeasure(1000 + index)
    }
    assertEquals(Pass.NORMAL, state.nextPass(400, false))
    assertEquals(Pass.FORCE, state.nextPass(400, true))
  }

  @Test fun contentChangeCanRestartAnExhaustedRound() {
    repeat(8) { index ->
      assertEquals(Pass.FORCE, state.nextPass(400, true))
      state.didMeasure(index)
    }
    state.invalidate()
    settle()
  }

  @Test fun loadingZerosDoNotCollapseThePlaceholderOrPreviousContent() {
    assertNull(state.heightToReport(0, 3f))
    assertEquals(300f, state.heightToReport(900, 3f))
    state.setContentEmpty(false)
    assertNull(state.heightToReport(0, 3f))
    assertNull(state.heightToReport(900, 3f))
  }

  @Test fun confirmedEmptyReportsZeroDespiteAStaleNativeHeight() {
    assertEquals(300f, state.heightToReport(900, 3f))
    state.setContentEmpty(true)
    assertEquals(0f, state.heightToReport(900, 3f))
    assertNull(state.heightToReport(0, 3f))
    state.setContentEmpty(false)
    assertNull(state.heightToReport(0, 3f))
    assertEquals(300f, state.heightToReport(900, 3f))
  }

  @Test fun initiallyEmptyFeedCollapsesOnlyOnce() {
    state.setContentEmpty(true)
    assertEquals(0f, state.heightToReport(0, 3f))
    state.invalidate()
    assertNull(state.heightToReport(0, 3f))
  }

  @Test fun deduplicatesRoundedDpInsteadOfPixels() {
    assertEquals(334f, state.heightToReport(1000, 3f))
    assertNull(state.heightToReport(1001, 3f))
    assertNull(state.heightToReport(1002, 3f))
    assertEquals(335f, state.heightToReport(1003, 3f))
  }

  @Test fun densityChangeCanReportANewHeightWithUnchangedPixels() {
    assertEquals(300f, state.heightToReport(900, 3f))
    assertEquals(450f, state.heightToReport(900, 2f))
  }

  @Test fun reattachmentRemeasuresWithoutRepeatingTheSameBridgeEvent() {
    settle()
    assertEquals(300f, state.heightToReport(900, 3f))
    state.invalidate()
    settle()
    assertNull(state.heightToReport(900, 3f))
  }
}