using BuildFlow.Shared.Domain.Exceptions;
using FluentAssertions;
using Microsoft.EntityFrameworkCore;
using Scripting.Application.Commands;
using Scripting.Application.Handlers;
using Scripting.Domain.Entities.ScriptFunction;
using Scripting.Domain.Enums;
using Scripting.Infrastructure.Persistence;
using Xunit;

namespace BuildFlow.Scripting.Tests;

/// <summary>
/// 脚本 CQRS 命令处理器测试（spec §13 #6 可编辑性、生命周期守卫）。
/// 用真实 InMemory ScriptingDbContext 直接实例化 handler，覆盖：
/// Create（唯一名校验 + 默认超时）、Update（Disabled 拒绝 + Published 自增版本）、
/// Delete（Published 拒绝 + Draft 软删除）、Publish（状态 + 版本）。
/// </summary>
public class ScriptCommandHandlerTests
{
    // ── Create ─────────────────────────────────────────────────────────────

    [Fact]
    public async Task CreateScript_DuplicateName_ThrowsBusinessException()
    {
        await using var db = ScriptingTestDbFactory.Create();
        await SeedAsync(db, name: "dup-fn");
        var handler = new CreateScriptCommandHandler(db);

        var act = () => handler.Handle(
            new CreateScriptCommand("dup-fn", "显示名", null, "return 1;", null, null, 0),
            CancellationToken.None);

        await act.Should().ThrowAsync<BusinessException>().WithMessage("*已存在*");
    }

    [Fact]
    public async Task CreateScript_DefaultsTimeoutTo5000()
    {
        await using var db = ScriptingTestDbFactory.Create();
        var handler = new CreateScriptCommandHandler(db);

        var dto = await handler.Handle(
            new CreateScriptCommand("default-timeout", "默认超时", null, "return 1;", null, null, 0),
            CancellationToken.None);

        dto.TimeoutMs.Should().Be(5000);
        dto.Status.Should().Be(ScriptStatusEnum.Draft);
        dto.Version.Should().Be(1);
        var entity = await db.Scripts.FindAsync(dto.Id);
        entity.Should().NotBeNull();
        entity!.TimeoutMs.Should().Be(5000);
    }

    [Fact]
    public async Task CreateScript_NewName_PersistsEntity()
    {
        await using var db = ScriptingTestDbFactory.Create();
        var handler = new CreateScriptCommandHandler(db);

        var dto = await handler.Handle(
            new CreateScriptCommand("unique-fn", "唯一函数", "desc", "return 42;", null, null, 3000),
            CancellationToken.None);

        dto.Name.Should().Be("unique-fn");
        dto.Code.Should().Be("return 42;");
        dto.TimeoutMs.Should().Be(3000);
    }

    // ── Update ─────────────────────────────────────────────────────────────

    [Fact]
    public async Task UpdateScript_DisabledScript_Throws()
    {
        await using var db = ScriptingTestDbFactory.Create();
        var script = await SeedAsync(db, name: "disabled-fn", status: ScriptStatusEnum.Disabled);
        var handler = new UpdateScriptCommandHandler(db);

        var act = () => handler.Handle(
            new UpdateScriptCommand(script.Id, "新名", null, "return 2;", null, null, 5000),
            CancellationToken.None);

        await act.Should().ThrowAsync<BusinessException>().WithMessage("*不能编辑*");
    }

    [Fact]
    public async Task UpdateScript_Published_IncrementsVersion()
    {
        await using var db = ScriptingTestDbFactory.Create();
        var script = await SeedAsync(db, name: "pub-fn", status: ScriptStatusEnum.Published, version: 3);
        var handler = new UpdateScriptCommandHandler(db);

        var dto = await handler.Handle(
            new UpdateScriptCommand(script.Id, "改后", null, "return 99;", null, null, 5000),
            CancellationToken.None);

        dto.Version.Should().Be(4);
        dto.DisplayName.Should().Be("改后");
        dto.Code.Should().Be("return 99;");
        dto.Status.Should().Be(ScriptStatusEnum.Published); // 保持已发布
    }

    [Fact]
    public async Task UpdateScript_Draft_KeepsVersionAtOne()
    {
        await using var db = ScriptingTestDbFactory.Create();
        var script = await SeedAsync(db, name: "draft-fn", status: ScriptStatusEnum.Draft);
        var handler = new UpdateScriptCommandHandler(db);

        var dto = await handler.Handle(
            new UpdateScriptCommand(script.Id, "草稿改", null, "return 1;", null, null, 5000),
            CancellationToken.None);

        dto.Version.Should().Be(1); // 草稿编辑不递增版本
    }

    // ── Delete ─────────────────────────────────────────────────────────────

    [Fact]
    public async Task DeleteScript_Published_Throws()
    {
        await using var db = ScriptingTestDbFactory.Create();
        var script = await SeedAsync(db, name: "del-pub", status: ScriptStatusEnum.Published);
        var handler = new DeleteScriptCommandHandler(db);

        var act = () => handler.Handle(new DeleteScriptCommand(script.Id), CancellationToken.None);

        await act.Should().ThrowAsync<BusinessException>().WithMessage("*不能删除*");
    }

    [Fact]
    public async Task DeleteScript_Draft_SoftDeletes()
    {
        await using var db = ScriptingTestDbFactory.Create();
        var script = await SeedAsync(db, name: "del-draft", status: ScriptStatusEnum.Draft);
        var handler = new DeleteScriptCommandHandler(db);

        await handler.Handle(new DeleteScriptCommand(script.Id), CancellationToken.None);

        var entity = await db.Scripts.IgnoreQueryFilters().FirstAsync(x => x.Id == script.Id);
        entity.IsDeleted.Should().BeTrue();
    }

    // ── Publish ────────────────────────────────────────────────────────────

    [Fact]
    public async Task PublishScript_SetsPublishedAndIncrementsVersion()
    {
        await using var db = ScriptingTestDbFactory.Create();
        var script = await SeedAsync(db, name: "to-publish", status: ScriptStatusEnum.Draft, version: 1);
        var handler = new PublishScriptCommandHandler(db);

        var dto = await handler.Handle(new PublishScriptCommand(script.Id), CancellationToken.None);

        dto.Status.Should().Be(ScriptStatusEnum.Published);
        dto.Version.Should().Be(2);
    }

    // ── 夹具 ───────────────────────────────────────────────────────────────

    private static async Task<ScriptFunctionEntity> SeedAsync(
        ScriptingDbContext db,
        string name,
        ScriptStatusEnum status = ScriptStatusEnum.Draft,
        int version = 1)
    {
        var script = new ScriptFunctionEntity
        {
            Id = Guid.NewGuid(),
            Name = name,
            DisplayName = name,
            Code = "return 1;",
            Status = status,
            Version = version,
            TimeoutMs = 5000,
            CreatedBy = "test",
            UpdatedBy = "test",
            OperatorIP = "127.0.0.1",
        };
        db.Scripts.Add(script);
        await db.SaveChangesAsync();
        return script;
    }
}