using Jiaowu.Api.Domain.Academic;
using Jiaowu.Api.Infrastructure.Exams;
using Jiaowu.Api.Infrastructure.Persistence;
using Microsoft.Data.Sqlite;
using Microsoft.EntityFrameworkCore;

namespace Jiaowu.Api.Tests;

public sealed class ExamArrangementServiceTests
{
    [Fact]
    public async Task Normal_arrangement_only_updates_selected_sessions_and_requested_resource()
    {
        await using var connection = new SqliteConnection("Data Source=:memory:");
        await connection.OpenAsync();
        var options = new DbContextOptionsBuilder<AppDbContext>()
            .UseSqlite(connection)
            .Options;
        await using var db = new AppDbContext(options);
        await db.Database.EnsureCreatedAsync();
        var seed = await SeedBaseDataAsync(db, "NORMAL");

        var plan = new ExamPlan
        {
            AcademicTermId = seed.Term.Id,
            Name = "期末考试"
        };
        var selected = NewExamSession(plan.Id, seed.FirstTask.Id);
        var untouched = NewExamSession(plan.Id, seed.SecondTask.Id);
        plan.Sessions.Add(selected);
        plan.Sessions.Add(untouched);
        db.ExamPlans.Add(plan);
        await db.SaveChangesAsync();
        db.ChangeTracker.Clear();

        var result = await new ExamArrangementService(db).ArrangeAsync(
            plan.Id,
            [selected.Id],
            assignClassrooms: true,
            assignInvigilators: false,
            CancellationToken.None);

        var persistedSelected = await db.ExamSessions.FindAsync(selected.Id);
        var persistedUntouched = await db.ExamSessions.FindAsync(untouched.Id);
        Assert.True(result.Success);
        Assert.NotNull(persistedSelected!.ClassroomId);
        Assert.Null(persistedUntouched!.ClassroomId);
        Assert.Empty(persistedSelected.Invigilators);
        Assert.Contains("1个场次处理完成", result.Message);
        Assert.Contains("程序设计", result.Message);
    }

    [Fact]
    public async Task Makeup_arrangement_only_updates_selected_sessions_and_requested_resource()
    {
        await using var connection = new SqliteConnection("Data Source=:memory:");
        await connection.OpenAsync();
        var options = new DbContextOptionsBuilder<AppDbContext>()
            .UseSqlite(connection)
            .Options;
        await using var db = new AppDbContext(options);
        await db.Database.EnsureCreatedAsync();
        var seed = await SeedBaseDataAsync(db, "MAKEUP");

        var plan = new MakeupExamPlan
        {
            AcademicTermId = seed.Term.Id,
            Name = "补考计划"
        };
        var selected = NewMakeupExamSession(plan.Id, seed.FirstTask.Id);
        var untouched = NewMakeupExamSession(plan.Id, seed.SecondTask.Id);
        plan.Sessions.Add(selected);
        plan.Sessions.Add(untouched);
        db.MakeupExamPlans.Add(plan);
        await db.SaveChangesAsync();
        db.ChangeTracker.Clear();

        var result = await new MakeupExamArrangementService(db).ArrangeAsync(
            plan.Id,
            [selected.Id],
            assignClassrooms: true,
            assignInvigilators: false,
            CancellationToken.None);

        var persistedSelected = await db.MakeupExamSessions.FindAsync(selected.Id);
        var persistedUntouched = await db.MakeupExamSessions.FindAsync(untouched.Id);
        Assert.True(result.Success);
        Assert.NotNull(persistedSelected!.ClassroomId);
        Assert.Null(persistedUntouched!.ClassroomId);
        Assert.Empty(persistedSelected.Invigilators);
        Assert.Contains("1个场次处理完成", result.Message);
        Assert.Contains("程序设计", result.Message);
    }

    private static ExamSession NewExamSession(Guid planId, Guid taskId) => new()
    {
        ExamPlanId = planId,
        TeachingTaskId = taskId,
        ExamDate = new DateOnly(2026, 12, 28),
        StartPeriod = 1,
        PeriodCount = 2,
        StartsAt = new DateTime(2026, 12, 28, 8, 0, 0, DateTimeKind.Utc),
        EndsAt = new DateTime(2026, 12, 28, 9, 50, 0, DateTimeKind.Utc),
        RequiredInvigilatorCount = 1
    };

    private static MakeupExamSession NewMakeupExamSession(Guid planId, Guid taskId) => new()
    {
        MakeupExamPlanId = planId,
        TeachingTaskId = taskId,
        ExamDate = new DateOnly(2026, 12, 28),
        StartPeriod = 1,
        PeriodCount = 2,
        StartsAt = new DateTime(2026, 12, 28, 8, 0, 0, DateTimeKind.Utc),
        EndsAt = new DateTime(2026, 12, 28, 9, 50, 0, DateTimeKind.Utc),
        RequiredInvigilatorCount = 1
    };

    private static async Task<SeedData> SeedBaseDataAsync(AppDbContext db, string suffix)
    {
        var term = new AcademicTerm
        {
            Code = $"2026-{suffix}",
            Name = $"2026 {suffix}",
            AcademicYear = "2026-2027",
            Season = TermSeason.Autumn,
            StartDate = new DateOnly(2026, 9, 1),
            EndDate = new DateOnly(2027, 1, 15)
        };
        var campus = new Campus { Code = $"C-{suffix}", Name = "主校区" };
        var college = new College
        {
            Code = $"COL-{suffix}",
            Name = "计算机学院",
            CampusId = campus.Id
        };
        var building = new Building
        {
            Code = $"B-{suffix}",
            Name = "第一教学楼",
            CampusId = campus.Id
        };
        var classroom = new Classroom
        {
            Code = $"R-{suffix}",
            Name = "101",
            BuildingId = building.Id,
            Capacity = 80
        };
        var firstCourse = new Course
        {
            Code = $"COURSE-1-{suffix}",
            Name = "程序设计",
            CollegeId = college.Id
        };
        var secondCourse = new Course
        {
            Code = $"COURSE-2-{suffix}",
            Name = "大学英语",
            CollegeId = college.Id
        };
        var firstTask = new TeachingTask
        {
            TaskNumber = $"TASK-1-{suffix}",
            Name = "程序设计教学班",
            AcademicTermId = term.Id,
            CourseId = firstCourse.Id,
            Status = TeachingTaskStatus.Published
        };
        var secondTask = new TeachingTask
        {
            TaskNumber = $"TASK-2-{suffix}",
            Name = "大学英语教学班",
            AcademicTermId = term.Id,
            CourseId = secondCourse.Id,
            Status = TeachingTaskStatus.Published
        };

        db.AddRange(
            term,
            campus,
            college,
            building,
            classroom,
            firstCourse,
            secondCourse,
            firstTask,
            secondTask,
            new ScheduleTimeSlot
            {
                AcademicTermId = term.Id,
                PeriodNumber = 1,
                Name = "第1节",
                StartsAt = new TimeOnly(8, 0),
                EndsAt = new TimeOnly(8, 45)
            },
            new ScheduleTimeSlot
            {
                AcademicTermId = term.Id,
                PeriodNumber = 2,
                Name = "第2节",
                StartsAt = new TimeOnly(9, 0),
                EndsAt = new TimeOnly(9, 50)
            });
        await db.SaveChangesAsync();
        return new SeedData(term, firstTask, secondTask);
    }

    private sealed record SeedData(
        AcademicTerm Term,
        TeachingTask FirstTask,
        TeachingTask SecondTask);
}