using AcDream.Core.CharGen;
using AcDream.Core.Net.Messages;
using AcDream.Runtime.Session;

namespace AcDream.Runtime.Tests.CharGen;

/// <summary>
/// Campaign CC slice CC3: <see cref="RuntimeCharacterCreationState"/> —
/// retail's <c>CharGenState</c> mirror. Every test cites the retail function
/// it is pinning; see the class's own doc comments for full addresses.
/// </summary>
public sealed class RuntimeCharacterCreationStateTests
{
    private static RuntimeCharacterCreationState CreateActive()
    {
        var state = new RuntimeCharacterCreationState(
            RuntimeCharacterCreationStateFixture.Build(),
            new Random(1234));
        state.Begin(new RuntimeGenerationToken(1));
        return state;
    }

    // ── Lifecycle ───────────────────────────────────────────────────────

    [Fact]
    public void Begin_StartsWithNoHeritageOrGenderSelected()
    {
        RuntimeCharacterCreationState state = CreateActive();
        RuntimeCharacterCreationSnapshot snapshot = state.Snapshot;

        Assert.True(snapshot.IsActive);
        Assert.Equal(0u, snapshot.HeritageId);
        Assert.Equal(0u, snapshot.GenderKey);
        Assert.Equal(RuntimeCharacterCreationSnapshot.TemplateUnset, snapshot.Template);
        Assert.Equal(-1, snapshot.StartArea);
        Assert.False(snapshot.VerificationPending);
        Assert.Equal(string.Empty, snapshot.Name);
    }

    [Fact]
    public void Reset_ClearsEveryFieldAndDeactivates()
    {
        RuntimeCharacterCreationState state = CreateActive();
        Assert.True(state.TrySelectHeritage(RuntimeCharacterCreationStateFixture.AluvianId));
        Assert.True(state.TrySelectGender(RuntimeCharacterCreationStateFixture.MaleGenderKey));
        Assert.True(state.TrySetName("Someone"));

        state.Reset(new RuntimeGenerationToken(2));

        RuntimeCharacterCreationSnapshot snapshot = state.Snapshot;
        Assert.False(snapshot.IsActive);
        Assert.Equal(0u, snapshot.HeritageId);
        Assert.Equal(0u, snapshot.GenderKey);
        Assert.Equal(string.Empty, snapshot.Name);
        Assert.Equal(RuntimeCharacterCreationSnapshot.TemplateUnset, snapshot.Template);
        // Commands are refused once inactive.
        Assert.False(state.TrySelectHeritage(RuntimeCharacterCreationStateFixture.AluvianId));
    }

    // ── Heritage / gender / template ────────────────────────────────────

    [Fact]
    public void TrySelectHeritage_UnknownId_IsRejected()
    {
        RuntimeCharacterCreationState state = CreateActive();
        Assert.False(state.TrySelectHeritage(0xDEADu));
        Assert.Equal(0u, state.Snapshot.HeritageId);
    }

    [Fact]
    public void TrySelectHeritage_RecomputesBudgetsAndRollsARandomPrimaryStartArea()
    {
        RuntimeCharacterCreationState state = CreateActive();

        Assert.True(state.TrySelectHeritage(RuntimeCharacterCreationStateFixture.AluvianId));

        RuntimeCharacterCreationSnapshot snapshot = state.Snapshot;
        Assert.Equal(RuntimeCharacterCreationStateFixture.AluvianId, snapshot.HeritageId);
        Assert.Equal(66u, snapshot.TotalAttributeCredits);
        Assert.Equal(50u, snapshot.TotalSkillCredits);
        // No template chosen yet — ApplyTemplate's own guard leaves
        // attributes untouched (CharGenState::ApplyTemplate @ 0x005C5080).
        Assert.Equal(0, snapshot.Attributes.Total);
        Assert.Equal(66, snapshot.RemainingAttributeCredits);
        // RandomizeStartArea @ 0x005C59E0 only ever picks from
        // PrimaryStartAreaIndices, [0, 1] in the fixture.
        Assert.True(snapshot.StartArea is 0 or 1);
    }

    [Fact]
    public void TrySelectGender_RequiresHeritageFirst()
    {
        RuntimeCharacterCreationState state = CreateActive();
        Assert.False(state.TrySelectGender(RuntimeCharacterCreationStateFixture.MaleGenderKey));
    }

    [Fact]
    public void TrySelectGender_UnknownKeyForHeritage_IsRejected()
    {
        RuntimeCharacterCreationState state = CreateActive();
        state.TrySelectHeritage(RuntimeCharacterCreationStateFixture.AluvianId);
        Assert.False(state.TrySelectGender(99u));
    }

    [Fact]
    public void TrySelectTemplate_Custom_AppliesFloorAttributesAndLeavesCreditsUnspent()
    {
        RuntimeCharacterCreationState state = CreateActive();
        state.TrySelectHeritage(RuntimeCharacterCreationStateFixture.AluvianId);
        state.TrySelectGender(RuntimeCharacterCreationStateFixture.MaleGenderKey);

        Assert.True(state.TrySelectTemplate(RuntimeCharacterCreationStateFixture.CustomTemplateIndex));

        RuntimeCharacterCreationSnapshot snapshot = state.Snapshot;
        Assert.Equal(0u, snapshot.Template);
        Assert.Equal(new ChargenAttributeValues(10, 10, 10, 10, 10, 10), snapshot.Attributes);
        // 66 budget - 60 floor spend = 6 unspent, matching CC1's "Custom
        // sits at the floor" finding.
        Assert.Equal(6, snapshot.RemainingAttributeCredits);
        Assert.Equal(
            ChargenSkillAdvancementClass.Trained,
            state.GetSkillLevel(RuntimeCharacterCreationStateFixture.SkillCustomNormal));
    }

    [Fact]
    public void TrySelectTemplate_Preset_TrainsNormalAndSpecializesPrimarySkills()
    {
        RuntimeCharacterCreationState state = CreateActive();
        state.TrySelectHeritage(RuntimeCharacterCreationStateFixture.AluvianId);
        state.TrySelectGender(RuntimeCharacterCreationStateFixture.MaleGenderKey);

        Assert.True(state.TrySelectTemplate(RuntimeCharacterCreationStateFixture.PresetTemplateIndex));

        RuntimeCharacterCreationSnapshot snapshot = state.Snapshot;
        Assert.Equal(new ChargenAttributeValues(16, 10, 10, 10, 10, 10), snapshot.Attributes);
        Assert.Equal(0, snapshot.RemainingAttributeCredits);
        Assert.Equal(
            ChargenSkillAdvancementClass.Trained,
            state.GetSkillLevel(RuntimeCharacterCreationStateFixture.SkillTrainSpecialize));
        Assert.Equal(
            ChargenSkillAdvancementClass.Specialized,
            state.GetSkillLevel(RuntimeCharacterCreationStateFixture.SkillPresetPrimary));
        // ResetSkillLevels' baseline (0x005C43B0) still holds for skills the
        // template row doesn't mention.
        Assert.Equal(
            ChargenSkillAdvancementClass.Specialized,
            state.GetSkillLevel(RuntimeCharacterCreationStateFixture.SkillFreeSpecialized));
        Assert.Equal(
            ChargenSkillAdvancementClass.Trained,
            state.GetSkillLevel(RuntimeCharacterCreationStateFixture.SkillFreeTrained));
    }

    [Fact]
    public void TrySelectTemplate_OlthoiHeritage_AlwaysForcesTemplateZero()
    {
        RuntimeCharacterCreationState state = CreateActive();
        state.TrySelectHeritage(RuntimeCharacterCreationStateFixture.OlthoiId);
        state.TrySelectGender(RuntimeCharacterCreationStateFixture.MaleGenderKey);

        // CharGenState::ApplyTemplate @ 0x005C5080: mHeritageGroup == 0xc
        // force-sets template_ = 0 regardless of the requested index.
        Assert.True(state.TrySelectTemplate(1u));

        Assert.Equal(0u, state.Snapshot.Template);
        Assert.Equal(new ChargenAttributeValues(10, 10, 10, 10, 10, 10), state.Snapshot.Attributes);
    }

    // ── Attributes ──────────────────────────────────────────────────────

    [Fact]
    public void TrySetAttribute_ClampsToTheFloorAndCeiling()
    {
        RuntimeCharacterCreationState state = CreateActive();
        state.TrySelectHeritage(RuntimeCharacterCreationStateFixture.AluvianId);
        state.TrySelectGender(RuntimeCharacterCreationStateFixture.MaleGenderKey);
        state.TrySelectTemplate(RuntimeCharacterCreationStateFixture.CustomTemplateIndex);

        Assert.True(state.TrySetAttribute(ChargenAttributeId.Strength, 5));
        Assert.Equal(10, state.Snapshot.Attributes.Strength);

        Assert.True(state.TrySetAttribute(ChargenAttributeId.Strength, 999));
        // Clamped further by the abs-remaining-credits check below 100.
        Assert.True(state.Snapshot.Attributes.Strength <= ChargenAttributeMath.AttributeMax);
    }

    [Fact]
    public void TrySetAttribute_RaisingOneAttributeRebalancesAnAboveFloorAttributeDownToTheFloor()
    {
        // CharGenState::BalanceAttributes @ 0x005C3DF0: starting from the
        // Preset template (Strength=16, everyone else at the 10 floor, fully
        // spent), raising Endurance consumes the "assumed floor" room
        // GetAbsRemainingCredits grants by pretending Strength could drop to
        // floor — BalanceAttributes then actually performs that drop.
        RuntimeCharacterCreationState state = CreateActive();
        state.TrySelectHeritage(RuntimeCharacterCreationStateFixture.AluvianId);
        state.TrySelectGender(RuntimeCharacterCreationStateFixture.MaleGenderKey);
        state.TrySelectTemplate(RuntimeCharacterCreationStateFixture.PresetTemplateIndex);

        Assert.True(state.TrySetAttribute(ChargenAttributeId.Endurance, 16));

        ChargenAttributeValues attrs = state.Snapshot.Attributes;
        Assert.Equal(16, attrs.Endurance);
        Assert.Equal(10, attrs.Strength);
        Assert.Equal(10, attrs.Coordination);
        Assert.Equal(10, attrs.Quickness);
        Assert.Equal(10, attrs.Focus);
        Assert.Equal(10, attrs.Self);
        Assert.Equal(66, attrs.Total);
        Assert.Equal(0, state.Snapshot.RemainingAttributeCredits);
    }

    [Fact]
    public void TrySetAttributeLock_PreventsThatAttributeFromAbsorbingABalance()
    {
        // CharGenState::LockAttribute @ 0x005C3BE0 + GetAbsRemainingCredits
        // @ 0x005C3B20's locked branch: a locked attribute contributes its
        // CURRENT value (not the floor) to the abs-remaining computation, so
        // no room is assumed available from it.
        RuntimeCharacterCreationState state = CreateActive();
        state.TrySelectHeritage(RuntimeCharacterCreationStateFixture.AluvianId);
        state.TrySelectGender(RuntimeCharacterCreationStateFixture.MaleGenderKey);
        state.TrySelectTemplate(RuntimeCharacterCreationStateFixture.PresetTemplateIndex);
        Assert.True(state.TrySetAttributeLock(ChargenAttributeId.Strength, true));

        Assert.True(state.TrySetAttribute(ChargenAttributeId.Endurance, 16));

        // No room was available (Strength locked at 16, everything else at
        // floor, budget already fully spent) — Endurance cannot rise.
        Assert.Equal(10, state.Snapshot.Attributes.Endurance);
        Assert.Equal(16, state.Snapshot.Attributes.Strength);
    }

    // ── Skills ──────────────────────────────────────────────────────────

    [Fact]
    public void TrySpecializeSkill_UncostableSkill_IsAlwaysRejected()
    {
        // Binding fact from the CC1 review (R1): the 16 uncostable skill ids
        // must never be settable — retail's own listbox never lists them.
        RuntimeCharacterCreationState state = CreateActive();
        state.TrySelectHeritage(RuntimeCharacterCreationStateFixture.AluvianId);
        state.TrySelectGender(RuntimeCharacterCreationStateFixture.MaleGenderKey);
        state.TrySelectTemplate(RuntimeCharacterCreationStateFixture.CustomTemplateIndex);

        Assert.False(state.TrySpecializeSkill(RuntimeCharacterCreationStateFixture.SkillUncostable));
        Assert.False(state.TryTrainSkill(RuntimeCharacterCreationStateFixture.SkillUncostable));
        Assert.False(state.TryUntrainSkill(RuntimeCharacterCreationStateFixture.SkillUncostable));
        Assert.Equal(
            ChargenSkillAdvancementClass.Inactive,
            state.GetSkillLevel(RuntimeCharacterCreationStateFixture.SkillUncostable));
    }

    [Fact]
    public void TrainThenSpecializeSkill_ChargesExactlyPrimaryCostNotBoth()
    {
        RuntimeCharacterCreationState state = CreateActive();
        state.TrySelectHeritage(RuntimeCharacterCreationStateFixture.AluvianId);
        state.TrySelectGender(RuntimeCharacterCreationStateFixture.MaleGenderKey);
        state.TrySelectTemplate(RuntimeCharacterCreationStateFixture.CustomTemplateIndex);
        int before = state.Snapshot.RemainingSkillCredits;

        Assert.True(state.TryTrainSkill(RuntimeCharacterCreationStateFixture.SkillTrainSpecialize));
        Assert.Equal(before - 4, state.Snapshot.RemainingSkillCredits);

        Assert.True(state.TrySpecializeSkill(RuntimeCharacterCreationStateFixture.SkillTrainSpecialize));
        // PrimaryCost (12) is the TOTAL, not an increment on NormalCost.
        Assert.Equal(before - 12, state.Snapshot.RemainingSkillCredits);

        Assert.True(state.TryUntrainSkill(RuntimeCharacterCreationStateFixture.SkillTrainSpecialize));
        Assert.Equal(before, state.Snapshot.RemainingSkillCredits);
    }

    [Fact]
    public void TrySpecializeSkill_InsufficientCredits_IsRejectedAndLeavesStateUnchanged()
    {
        RuntimeCharacterCreationState state = CreateActive();
        state.TrySelectHeritage(RuntimeCharacterCreationStateFixture.ImpoverishedId);
        state.TrySelectGender(RuntimeCharacterCreationStateFixture.MaleGenderKey);
        state.TrySelectTemplate(RuntimeCharacterCreationStateFixture.CustomTemplateIndex);
        Assert.Equal(5, state.Snapshot.RemainingSkillCredits);

        // PrimaryCost (12) exceeds the 5-credit budget outright.
        Assert.False(state.TrySpecializeSkill(RuntimeCharacterCreationStateFixture.SkillTrainSpecialize));
        Assert.Equal(5, state.Snapshot.RemainingSkillCredits);
        Assert.Equal(
            ChargenSkillAdvancementClass.Untrained,
            state.GetSkillLevel(RuntimeCharacterCreationStateFixture.SkillTrainSpecialize));

        // NormalCost (4) fits; the SAME skill Specialized still does not.
        Assert.True(state.TryTrainSkill(RuntimeCharacterCreationStateFixture.SkillTrainSpecialize));
        Assert.Equal(1, state.Snapshot.RemainingSkillCredits);
        Assert.False(state.TrySpecializeSkill(RuntimeCharacterCreationStateFixture.SkillTrainSpecialize));
        Assert.Equal(1, state.Snapshot.RemainingSkillCredits);
        Assert.Equal(
            ChargenSkillAdvancementClass.Trained,
            state.GetSkillLevel(RuntimeCharacterCreationStateFixture.SkillTrainSpecialize));
    }

    // ── Finish gates ────────────────────────────────────────────────────

    private static RuntimeCharacterCreationState ReadyToFinishState()
    {
        RuntimeCharacterCreationState state = CreateActive();
        state.TrySelectHeritage(RuntimeCharacterCreationStateFixture.AluvianId);
        state.TrySelectGender(RuntimeCharacterCreationStateFixture.MaleGenderKey);
        state.TrySelectTemplate(RuntimeCharacterCreationStateFixture.PresetTemplateIndex); // fully spent attrs
        state.TrySetName("Adventurer");
        return state;
    }

    [Fact]
    public void TryBeginFinish_EmptyName_IsRefused()
    {
        RuntimeCharacterCreationState state = ReadyToFinishState();
        state.TrySetName("   ");

        bool accepted = state.TryBeginFinish(
            rosterCount: 0,
            slotCount: 11,
            out _,
            out _,
            out RuntimeCharacterCreationLocalRefusal refusal);

        Assert.False(accepted);
        Assert.True(refusal.NoName);
        Assert.False(state.Snapshot.VerificationPending);
    }

    [Fact]
    public void TryBeginFinish_UnspentAttributeCredits_IsRefused()
    {
        RuntimeCharacterCreationState state = CreateActive();
        state.TrySelectHeritage(RuntimeCharacterCreationStateFixture.AluvianId);
        state.TrySelectGender(RuntimeCharacterCreationStateFixture.MaleGenderKey);
        state.TrySelectTemplate(RuntimeCharacterCreationStateFixture.CustomTemplateIndex); // 6 unspent
        state.TrySetName("Adventurer");

        bool accepted = state.TryBeginFinish(
            0, 11, out _, out _, out RuntimeCharacterCreationLocalRefusal refusal);

        Assert.False(accepted);
        Assert.True(refusal.AttributeCreditsUnspent);
    }

    [Fact]
    public void TryBeginFinish_SecondCallWhilePending_IsRefused()
    {
        RuntimeCharacterCreationState state = ReadyToFinishState();
        Assert.True(state.TryBeginFinish(
            0, 11, out _, out _, out RuntimeCharacterCreationLocalRefusal first));
        Assert.False(first.Any);

        bool second = state.TryBeginFinish(
            0, 11, out _, out _, out RuntimeCharacterCreationLocalRefusal refusal);

        Assert.False(second);
        Assert.True(refusal.AlreadyPending);
    }

    [Fact]
    public void TryBeginFinish_RosterAtSlotCap_IsRefused()
    {
        RuntimeCharacterCreationState state = ReadyToFinishState();

        bool accepted = state.TryBeginFinish(
            rosterCount: 11,
            slotCount: 11,
            out _,
            out _,
            out RuntimeCharacterCreationLocalRefusal refusal);

        Assert.False(accepted);
        Assert.True(refusal.RosterFull);
    }

    [Fact]
    public void TryBeginFinish_Accepted_TrimsNameAndProducesExactly55SkillSlots()
    {
        RuntimeCharacterCreationState state = ReadyToFinishState();
        state.TrySetName("  Adventurer  ");

        bool accepted = state.TryBeginFinish(
            rosterCount: 2,
            slotCount: 11,
            out CharacterCreate.Request request,
            out uint[] skillAdvancementClasses,
            out RuntimeCharacterCreationLocalRefusal refusal);

        Assert.True(accepted);
        Assert.False(refusal.Any);
        Assert.True(state.Snapshot.VerificationPending);
        Assert.Equal("Adventurer", request.Name);
        Assert.Equal(RuntimeCharacterCreationStateFixture.AluvianId, request.Heritage);
        Assert.Equal(RuntimeCharacterCreationStateFixture.MaleGenderKey, request.Gender);
        Assert.Equal(RuntimeCharacterCreationStateFixture.PresetTemplateIndex, request.Template);
        Assert.Equal(16u, request.Attributes.Strength);
        Assert.Equal(CharacterCreate.SkillAdvancementClassCount, skillAdvancementClasses.Length);
        Assert.Equal(
            (uint)ChargenSkillAdvancementClass.Trained,
            skillAdvancementClasses[RuntimeCharacterCreationStateFixture.SkillTrainSpecialize]);
        Assert.Equal(
            (uint)ChargenSkillAdvancementClass.Specialized,
            skillAdvancementClasses[RuntimeCharacterCreationStateFixture.SkillPresetPrimary]);
    }

    // ── Response handling ───────────────────────────────────────────────

    private static RuntimeCharacterCreationState PendingState(out uint[] skills)
    {
        RuntimeCharacterCreationState state = ReadyToFinishState();
        Assert.True(state.TryBeginFinish(0, 11, out _, out skills, out _));
        return state;
    }

    [Fact]
    public void ApplyCreationResponse_Ok_RecordsCreatedIdentityAndClearsPending()
    {
        RuntimeCharacterCreationState state = PendingState(out _);

        state.ApplyCreationResponse(new CharGenVerificationResponse.Parsed(
            (uint)CharGenVerificationResponse.Code.Ok, 0x5000_1234u, "Adventurer", 0u));

        RuntimeCharacterCreationSnapshot snapshot = state.Snapshot;
        Assert.False(snapshot.VerificationPending);
        Assert.Equal(
            new RuntimeCharacterCreationIdentity(0x5000_1234u, "Adventurer"),
            snapshot.LastCreated);
        Assert.Null(snapshot.LastRejection);
    }

    [Theory]
    [InlineData(CharGenVerificationResponse.Code.NameInUse)]
    [InlineData(CharGenVerificationResponse.Code.NameBanned)]
    [InlineData(CharGenVerificationResponse.Code.Corrupt)]
    [InlineData(CharGenVerificationResponse.Code.DatabaseDown)]
    [InlineData(CharGenVerificationResponse.Code.AdminPrivilegeDenied)]
    public void ApplyCreationResponse_EachRejectionCode_RecordsTheMappingAndAttemptedName(
        CharGenVerificationResponse.Code code)
    {
        RuntimeCharacterCreationState state = PendingState(out _);

        state.ApplyCreationResponse(new CharGenVerificationResponse.Parsed(
            (uint)code, null, null, null));

        Assert.NotNull(state.Snapshot.LastRejection);
        RuntimeCharacterCreationRejection rejection = state.Snapshot.LastRejection!.Value;
        Assert.Equal(code, rejection.Code);
        Assert.Equal(code.ToString(), rejection.Reason);
        Assert.Equal("Adventurer", rejection.AttemptedName);
        Assert.False(state.Snapshot.VerificationPending);
        Assert.Null(state.Snapshot.LastCreated);
    }

    [Theory]
    [InlineData(CharGenVerificationResponse.Code.Pending)]
    [InlineData(CharGenVerificationResponse.Code.Undef)]
    public void ApplyCreationResponse_PendingOrUndef_IsASilentResetWithNoRejection(
        CharGenVerificationResponse.Code code)
    {
        // ACE sends Pending for a disabled-Olthoi rejection — retail shows
        // no dialog. Port as-is.
        RuntimeCharacterCreationState state = PendingState(out _);

        state.ApplyCreationResponse(new CharGenVerificationResponse.Parsed(
            (uint)code, null, null, null));

        Assert.False(state.Snapshot.VerificationPending);
        Assert.Null(state.Snapshot.LastRejection);
        Assert.Null(state.Snapshot.LastCreated);
    }

    [Fact]
    public void ApplyCreationResponse_DuplicateReplyWhileNotPending_IsIgnored()
    {
        // ACE's own quirk (CharacterHandler.CharacterCreateEx calls
        // IsCharacterNameAvailable TWICE, producing two NameInUse replies
        // for one rejected create): the second reply must be a no-op, not a
        // second rejection event/state change.
        RuntimeCharacterCreationState state = PendingState(out _);
        state.ApplyCreationResponse(new CharGenVerificationResponse.Parsed(
            (uint)CharGenVerificationResponse.Code.NameInUse, null, null, null));
        Assert.NotNull(state.Snapshot.LastRejection);

        // Acknowledge to clear, then feed a SECOND unsolicited reply — must
        // stay cleared (idempotent-tolerant, no crash, no new rejection).
        Assert.True(state.TryAcknowledgeRejection());
        state.ApplyCreationResponse(new CharGenVerificationResponse.Parsed(
            (uint)CharGenVerificationResponse.Code.NameInUse, null, null, null));

        Assert.Null(state.Snapshot.LastRejection);
    }

    [Fact]
    public void TryAcknowledgeRejection_ClearsTheSurfacedRejection()
    {
        RuntimeCharacterCreationState state = PendingState(out _);
        state.ApplyCreationResponse(new CharGenVerificationResponse.Parsed(
            (uint)CharGenVerificationResponse.Code.NameBanned, null, null, null));
        Assert.NotNull(state.Snapshot.LastRejection);

        Assert.True(state.TryAcknowledgeRejection());

        Assert.Null(state.Snapshot.LastRejection);
    }
}