using Amphora;
using System;
using System.Collections.Generic;
using UnitTestSharp;

namespace Glass.UnitTests
{
    public class EntryTypeAheadTests : TestFixture
    {
        private static readonly Duration OneSecond = Duration.FromSeconds(1);

        private static FileEntry[] Files(params string[] names)
        {
            var returnMe = new FileEntry[names.Length];

            for (int i = 0; i < names.Length; ++i)
            {
                returnMe[i] = new FileEntry(names[i], IsDirectory: false);
            }

            return returnMe;
        }

        public class FindTests : TestFixture
        {
            public void AName_IsFoundByTheCharactersItStartsWith()
            {
                var typeAhead = new EntryTypeAhead();

                CheckEqual(2, typeAhead.Find(Files("alpha", "apple", "banana"), null, "b"));
            }

            public void TheMatch_IgnoresCase()
            {
                var typeAhead = new EntryTypeAhead();

                CheckEqual(1, typeAhead.Find(Files("Alpha", "BANANA"), null, "bAn"));
            }

            public void NothingSelected_StartsAtTheTop()
            {
                var typeAhead = new EntryTypeAhead();

                CheckEqual(0, typeAhead.Find(Files("alpha", "apple"), null, "a"));
            }

            public void ASelection_IsWhereTheSearchStarts()
            {
                var typeAhead = new EntryTypeAhead();

                CheckEqual(2, typeAhead.Find(Files("apple", "banana", "avocado"), 1, "a"));
            }

            public void TheSearch_WrapsPastTheEnd()
            {
                var typeAhead = new EntryTypeAhead();

                CheckEqual(0, typeAhead.Find(Files("alpha", "banana", "cherry"), 2, "a"));
            }

            public void TheSelection_WinsWhileItStillFits()
            {
                var typeAhead = new EntryTypeAhead();

                CheckEqual(1, typeAhead.Find(Files("apple", "apricot"), 1, "a"));
            }

            public void AnotherCharacter_MovesOnOnceTheSelectionStopsFitting()
            {
                var typeAhead = new EntryTypeAhead();
                FileEntry[] entries = Files("apple", "apricot", "banana");

                CheckEqual(0, typeAhead.Find(entries, null, "a"));
                CheckEqual(0, typeAhead.Find(entries, 0, "p"));
                CheckEqual(1, typeAhead.Find(entries, 0, "r"));
            }

            public void SeveralCharactersAtOnce_AreAddedWhole()
            {
                var typeAhead = new EntryTypeAhead();

                CheckEqual(1, typeAhead.Find(Files("banana", "apple"), null, "ap"));
                CheckEqual("ap", typeAhead.Typed);
            }

            public void NothingFitting_ReturnsNullAndKeepsTheCharacters()
            {
                var typeAhead = new EntryTypeAhead();

                CheckNull(typeAhead.Find(Files("alpha", "banana"), 1, "x"));
                CheckEqual("x", typeAhead.Typed);
            }

            public void AnEmptyList_ReturnsNull()
            {
                var typeAhead = new EntryTypeAhead();

                CheckNull(typeAhead.Find(Files(), null, "a"));
            }

            public void NoCharacters_ReturnsNullAndChangesNothing()
            {
                var typeAhead = new EntryTypeAhead();
                typeAhead.Find(Files("alpha"), null, "a");

                CheckNull(typeAhead.Find(Files("alpha"), 0, ""));
                CheckEqual("a", typeAhead.Typed);
            }

            public void ASelectionSomethingElseMoved_StartsANewSearch()
            {
                var typeAhead = new EntryTypeAhead();
                FileEntry[] entries = Files("apple", "banana", "cherry");
                typeAhead.Find(entries, null, "b");

                CheckEqual(0, typeAhead.Find(entries, 2, "a"));
                CheckEqual("a", typeAhead.Typed);
            }

            public void ARepeatedCharacter_CyclesThroughTheNamesItStarts()
            {
                var typeAhead = new EntryTypeAhead();
                FileEntry[] entries = Files("apple", "avocado", "banana", "apricot");

                CheckEqual(0, typeAhead.Find(entries, null, "a"));
                CheckEqual(1, typeAhead.Find(entries, 0, "a"));
                CheckEqual(3, typeAhead.Find(entries, 1, "a"));
                CheckEqual(0, typeAhead.Find(entries, 3, "a"));
            }

            public void ARepeatedCharacter_TypesARealNameThatStartsWithTheRepeats()
            {
                var typeAhead = new EntryTypeAhead();
                FileEntry[] entries = Files("alpha", "aardvark", "apple");

                CheckEqual(0, typeAhead.Find(entries, null, "a"));
                CheckEqual(1, typeAhead.Find(entries, 0, "a"));
            }

            public void DifferentCharacters_DoNotCycle()
            {
                var typeAhead = new EntryTypeAhead();
                FileEntry[] entries = Files("apple", "avocado");
                typeAhead.Find(entries, null, "a");

                CheckNull(typeAhead.Find(entries, 0, "z"));
            }

            public void NullEntries_Throws()
            {
                CheckThrow(typeof(ArgumentNullException));
                new EntryTypeAhead().Find(null, null, "a");
            }

            public void NullText_Throws()
            {
                CheckThrow(typeof(ArgumentNullException));
                new EntryTypeAhead().Find(Files("a"), null, null);
            }

            public void ASelectionPastTheEnd_Throws()
            {
                CheckThrow(typeof(ArgumentOutOfRangeException));
                new EntryTypeAhead().Find(Files("a"), 1, "a");
            }

            public void ANegativeSelection_Throws()
            {
                CheckThrow(typeof(ArgumentOutOfRangeException));
                new EntryTypeAhead().Find(Files("a"), -1, "a");
            }
        }

        public class ResetTests : TestFixture
        {
            public void Always_ForgetsTheCharacters()
            {
                var typeAhead = new EntryTypeAhead();
                typeAhead.Find(Files("alpha"), null, "a");

                typeAhead.Reset();

                CheckEqual("", typeAhead.Typed);
            }
        }

        public class WaitTests : TestFixture
        {
            public void ALongEnoughQuiet_ForgetsTheCharacters()
            {
                var typeAhead = new EntryTypeAhead();
                typeAhead.Find(Files("alpha"), null, "a");

                typeAhead.Wait(Duration.FromMilliseconds(600), OneSecond);
                CheckEqual("a", typeAhead.Typed);

                typeAhead.Wait(Duration.FromMilliseconds(400), OneSecond);
                CheckEqual("", typeAhead.Typed);
            }

            public void TypingAnotherCharacter_RestartsTheQuiet()
            {
                var typeAhead = new EntryTypeAhead();
                FileEntry[] entries = Files("apple");
                typeAhead.Find(entries, null, "a");
                typeAhead.Wait(Duration.FromMilliseconds(900), OneSecond);
                typeAhead.Find(entries, 0, "p");

                typeAhead.Wait(Duration.FromMilliseconds(900), OneSecond);

                CheckEqual("ap", typeAhead.Typed);
            }

            public void WaitingWithNothingTyped_CountsNothingTowardTheNextSearch()
            {
                var typeAhead = new EntryTypeAhead();
                typeAhead.Wait(Duration.FromSeconds(10), OneSecond);
                typeAhead.Find(Files("alpha"), null, "a");

                typeAhead.Wait(Duration.FromMilliseconds(500), OneSecond);

                CheckEqual("a", typeAhead.Typed);
            }
        }
    }
}