// See LICENSE for license details.

package chiselTests.stage

import org.scalatest.{FlatSpec, Matchers}

import chisel3._
import chisel3.stage.{ChiselCircuitAnnotation, ChiselGeneratorAnnotation}
import chisel3.experimental.RawModule

import firrtl.options.OptionsException

class ChiselAnnotationsSpecFoo extends RawModule {
  val in = IO(Input(Bool()))
  val out = IO(Output(Bool()))
  out := ~in
}

class ChiselAnnotationsSpecBaz(name: String) extends ChiselAnnotationsSpecFoo {
  override val desiredName = name
}

class ChiselAnnotationsSpecQux extends ChiselAnnotationsSpecFoo {
  /* This printf requires an implicit clock and reset, but RawModule has none. This will thereby fail elaboration. */
  printf("hello")
}

class ChiselAnnotation

class ChiselAnnotationsSpec extends FlatSpec with Matchers {

  behavior of "ChiselGeneratorAnnotation elaboration"

  it should "elaborate to a ChiselCircuitAnnotation" in {
    val annotation = ChiselGeneratorAnnotation(() => new ChiselAnnotationsSpecFoo)
    annotation.elaborate shouldBe a [ChiselCircuitAnnotation]
  }

  it should "throw an exception if elaboration fails" in {
    val annotation = ChiselGeneratorAnnotation(() => new ChiselAnnotationsSpecQux)
    intercept [ChiselException] { annotation.elaborate }
  }

  behavior of "ChiselGeneratorAnnotation when stringly constructing from Module names"

  it should "elaborate from a String" in {
    val annotation = ChiselGeneratorAnnotation("chiselTests.stage.ChiselAnnotationsSpecFoo")
    annotation.elaborate shouldBe a [ChiselCircuitAnnotation]
  }

  it should "throw an exception if elaboration from a String refers to nonexistant class" in {
    val bar = "chiselTests.stage.ChiselAnnotationsSpecBar"
    val annotation = ChiselGeneratorAnnotation(bar)
    intercept [OptionsException] { annotation.elaborate }
      .getMessage should startWith (s"Unable to locate module '$bar'")
  }

  it should "throw an exception if elaboration from a String refers to an anonymous class" in {
    val baz = "chiselTests.stage.ChiselAnnotationsSpecBaz"
    val annotation = ChiselGeneratorAnnotation(baz)
    intercept [OptionsException] { annotation.elaborate }
      .getMessage should startWith (s"Unable to create instance of module '$baz'")
  }

}
