using System.Collections.Generic;
using AcDream.Core.Physics;
using Xunit;

namespace AcDream.Core.Tests.Physics;

/// <summary>
/// Validates the dual command-catalog seam introduced for the L.1b
/// movement/animation wire-parity slice (<c>IMotionCommandCatalog</c>).
///
/// <para>
/// Two catalogs exist because the local DATs and ACE's wire protocol use a
/// LATER-client command numbering than the Sept 2013 EoR decomp:
/// <see cref="AceModernCommandCatalog"/> (runtime default — matches ACE +
/// local DAT MotionTables) and <see cref="Retail2013CommandCatalog"/>
/// (conformance/reference — matches the 2013 decomp's
/// <c>command_ids[0x198]</c> table verbatim). See
/// <c>docs/research/2026-06-26-ace-vs-2013-motion-command-gap.md</c> for the
/// full divergence analysis (130 common names with different values; the
/// contiguous low-word "+3" shift that begins at <c>SnowAngelState</c>
/// (0x43000115 -&gt; 0x43000118), NOT at <c>AllegianceHometownRecall</c> as an
/// earlier code comment incorrectly claimed).
/// </para>
/// </summary>
public class MotionCommandCatalogTests
{
    private static readonly AceModernCommandCatalog AceModern = new();
    private static readonly Retail2013CommandCatalog Retail2013 = new();

    // ── ACE mode (AceModernCommandCatalog) ──────────────────────────────
    //
    // These four wires sit inside the old override range (0x016E-0x0197)
    // that MotionCommandResolver used to force-map via a blind per-range
    // override. Built cleanly from the DatReaderWriter MotionCommand enum,
    // they already resolve correctly with NO override:
    //   LifestoneRecall = 0x10000153, MarketplaceRecall = 0x10000166,
    //   AllegianceHometownRecall = 0x10000171, OffhandSlashHigh = 0x10000173
    // (DatReaderWriter.Enums.MotionCommand, Chorizite.DatReaderWriter 2.1.7).

    [Theory]
    [InlineData(0x0153, 0x10000153u)] // LifestoneRecall
    [InlineData(0x0166, 0x10000166u)] // MarketplaceRecall
    [InlineData(0x0171, 0x10000171u)] // AllegianceHometownRecall
    [InlineData(0x0173, 0x10000173u)] // OffhandSlashHigh
    public void AceModern_ResolvesShiftedRecallAndActionCommands(ushort wire, uint expected)
    {
        Assert.Equal(expected, AceModern.ReconstructFullCommand(wire));
    }

    // Same matrix as MotionCommandResolverTests.ReconstructsKnownCommands —
    // proves AceModernCommandCatalog reproduces the existing resolver's
    // behavior for the well-established low end of the command space.
    [Theory]
    [InlineData(0x0003, 0x41000003u)]   // Ready
    [InlineData(0x0005, 0x45000005u)]   // WalkForward
    [InlineData(0x0007, 0x44000007u)]   // RunForward
    [InlineData(0x0006, 0x45000006u)]   // WalkBackward
    [InlineData(0x000D, 0x6500000Du)]   // TurnRight
    [InlineData(0x000E, 0x6500000Eu)]   // TurnLeft
    [InlineData(0x000F, 0x6500000Fu)]   // SideStepRight
    [InlineData(0x0015, 0x40000015u)]   // Falling
    [InlineData(0x0011, 0x40000011u)]   // Dead
    [InlineData(0x0012, 0x41000012u)]   // Crouch
    [InlineData(0x0013, 0x41000013u)]   // Sitting
    [InlineData(0x0014, 0x41000014u)]   // Sleeping
    [InlineData(0x0057, 0x10000057u)]   // Sanctuary (death)
    [InlineData(0x0058, 0x10000058u)]   // ThrustMed
    [InlineData(0x005B, 0x1000005Bu)]   // SlashHigh
    [InlineData(0x0061, 0x10000061u)]   // Shoot
    [InlineData(0x004B, 0x1000004Bu)]   // Jumpup
    [InlineData(0x0050, 0x10000050u)]   // FallDown
    [InlineData(0x0087, 0x13000087u)]   // Wave
    [InlineData(0x0080, 0x13000080u)]   // Laugh
    [InlineData(0x007D, 0x1300007Du)]   // BowDeep
    public void AceModern_MatchesExistingResolverMatrix(ushort wire, uint expected)
    {
        Assert.Equal(expected, AceModern.ReconstructFullCommand(wire));
    }

    // ── 2013 mode (Retail2013CommandCatalog) ────────────────────────────
    //
    // Direct-index reconstruction from acclient_2013_pseudo_c.txt's
    // command_ids[0x198] table at 0x007c73e8 (line 1017259). The 2013
    // decomp's *unshifted* values for the same four logical commands.

    [Theory]
    [InlineData(0x0150, 0x10000150u)] // LifestoneRecall (2013 value)
    [InlineData(0x0163, 0x10000163u)] // MarketplaceRecall (2013 value)
    [InlineData(0x016E, 0x1000016Eu)] // AllegianceHometownRecall (2013 value)
    [InlineData(0x0170, 0x10000170u)] // OffhandSlashHigh (2013 value)
    public void Retail2013_ResolvesUnshiftedRecallAndActionCommands(ushort wire, uint expected)
    {
        Assert.Equal(expected, Retail2013.ReconstructFullCommand(wire));
    }

    // Anchor checks straight off the extracted table — these pin the
    // extraction itself, independent of the recall-command narrative.
    [Theory]
    [InlineData(0x0000, 0x80000000u)]
    [InlineData(0x0003, 0x41000003u)]
    [InlineData(0x0005, 0x45000005u)]
    [InlineData(0x0007, 0x44000007u)]
    [InlineData(0x000D, 0x6500000Du)]
    [InlineData(0x0150, 0x10000150u)]
    [InlineData(0x0153, 0x09000153u)] // NOT LifestoneRecall in 2013 numbering — anchor only.
    public void Retail2013_AnchorValuesMatchExtractedTable(ushort wire, uint expected)
    {
        Assert.Equal(expected, Retail2013.ReconstructFullCommand(wire));
    }

    [Fact]
    public void Retail2013_OutOfRangeWireReturnsZero()
    {
        Assert.Equal(0u, Retail2013.ReconstructFullCommand(0xFFFF));
    }

    [Fact]
    public void Retail2013_LastInRangeIndexResolves()
    {
        // [0x197] is the final entry of command_ids[0x198].
        Assert.Equal(0x10000197u, Retail2013.ReconstructFullCommand(0x0197));
    }

    [Fact]
    public void Retail2013_FirstOutOfRangeIndexReturnsZero()
    {
        // 0x198 is one past the table's last valid index.
        Assert.Equal(0u, Retail2013.ReconstructFullCommand(0x0198));
    }

    // ── Class-priority collision resolution ─────────────────────────────
    //
    // Retail's class-byte priority is: lower class byte wins
    // (Action 0x10 < ChatEmote 0x12/0x13 < Modifier 0x20 < SubState 0x41
    // < ... < Style 0x80). This is exercised directly against the build
    // logic via a small synthetic set of colliding low-words, because the
    // CURRENT DatReaderWriter.Enums.MotionCommand enum (2.1.7, 409 distinct
    // values) happens to contain zero same-low16 collisions today — so a
    // matrix test against the live enum alone wouldn't actually exercise
    // the tie-break rule.

    [Fact]
    public void ClassPriority_LowerClassByteWins()
    {
        var candidates = new Dictionary<ushort, uint>
        {
            // Same low word (0x0042) claimed by three different classes;
            // Action (0x10) must win over Modifier (0x20) and Style (0x80).
            [0x0042] = 0u,
        };

        uint[] colliding = { 0x80000042u, 0x20000042u, 0x10000042u };
        uint resolved = AceModernCommandCatalog.ResolveClassPriority(colliding);

        Assert.Equal(0x10000042u, resolved);
    }

    [Fact]
    public void ClassPriority_OrderOfInputDoesNotMatter()
    {
        uint[] collidingReversed = { 0x10000099u, 0x41000099u, 0x80000099u };
        uint[] collidingForward = { 0x80000099u, 0x41000099u, 0x10000099u };

        Assert.Equal(
            AceModernCommandCatalog.ResolveClassPriority(collidingForward),
            AceModernCommandCatalog.ResolveClassPriority(collidingReversed));
        Assert.Equal(0x10000099u, AceModernCommandCatalog.ResolveClassPriority(collidingForward));
    }
}