import { describe, it } from "@effect/vitest"
import { deepStrictEqual, strictEqual } from "@effect/vitest/utils"
import { MutableList } from "effect"

describe("MutableList", () => {
  it("appendAll returns 0 and leaves an empty list empty", () => {
    const list = MutableList.make<number>()

    strictEqual(MutableList.appendAll(list, []), 0)
    strictEqual(list.length, 0)
    strictEqual(list.head, undefined)
    strictEqual(list.tail, undefined)
    strictEqual(MutableList.take(list), MutableList.Empty)
  })

  it("appendAll with empty iterables preserves later append order", () => {
    const list = MutableList.make<number>()

    MutableList.appendAll(list, [])
    MutableList.append(list, 1)
    MutableList.appendAll(list, [])
    MutableList.append(list, 2)

    deepStrictEqual(MutableList.takeAll(list), [1, 2])
    strictEqual(MutableList.take(list), MutableList.Empty)
  })

  it("appendAllUnsafe with an empty array is a no-op", () => {
    const list = MutableList.make<number>()

    MutableList.appendAll(list, [1])
    strictEqual(MutableList.appendAllUnsafe(list, []), 0)
    MutableList.append(list, 2)

    deepStrictEqual(MutableList.takeAll(list), [1, 2])
    strictEqual(MutableList.take(list), MutableList.Empty)
  })

  it("filter keeps matching values in place and updates length", () => {
    const list = MutableList.make<number>()
    MutableList.appendAll(list, [1, 2, 3, 4, 5])

    MutableList.filter(list, (n) => n % 2 === 0)

    deepStrictEqual(MutableList.toArrayN(list, 2), [2, 4])
    strictEqual(list.length, 2)
  })

  it("remove deletes all strictly equal values and updates length", () => {
    const list = MutableList.make<string>()
    MutableList.appendAll(list, ["apple", "banana", "apple", "cherry", "apple"])

    MutableList.remove(list, "apple")

    deepStrictEqual(MutableList.toArrayN(list, 2), ["banana", "cherry"])
    strictEqual(list.length, 2)
  })
})