using Health.Domain.Entities;

namespace Health.Application.HealthArchives;

public sealed class HealthArchiveService(IHealthArchiveRepository archives) : IHealthArchiveService
{
    private readonly IHealthArchiveRepository _archives = archives;

    public async Task<HealthArchiveDto?> GetAsync(Guid userId, CancellationToken ct)
    {
        var archive = await _archives.GetByUserIdAsync(userId, ct);
        return archive == null ? null : ToDto(archive);
    }

    public async Task<HealthArchiveDto> GetOrCreateAsync(Guid userId, CancellationToken ct)
    {
        var archive = await GetOrCreateEntityAsync(userId, ct);
        await _archives.SaveChangesAsync(ct);
        return ToDto(archive);
    }

    public async Task<HealthArchiveDto> UpdateAsync(Guid userId, HealthArchiveUpdateRequest request, CancellationToken ct)
    {
        var archive = await GetOrCreateEntityAsync(userId, ct);
        Apply(archive, request);
        archive.UpdatedAt = DateTime.UtcNow;
        await _archives.SaveChangesAsync(ct);
        return ToDto(archive);
    }

    public async Task<object> ExecuteAiActionAsync(Guid userId, string action, HealthArchiveUpdateRequest request, CancellationToken ct)
    {
        if (action == "query")
        {
            var archive = await GetAsync(userId, ct);
            return archive == null ? new { found = false } : ToAiResult(archive);
        }

        var current = await GetOrCreateEntityAsync(userId, ct);
        var scopedRequest = action switch
        {
            "update_diagnosis" => request with
            {
                SurgeryType = null, SurgeryDate = null, Allergies = null,
                DietRestrictions = null, ChronicDiseases = null, FamilyHistory = null
            },
            "update_surgery" => request with
            {
                Diagnosis = null, Allergies = null, DietRestrictions = null,
                ChronicDiseases = null, FamilyHistory = null
            },
            "update_allergies" => new HealthArchiveUpdateRequest(null, null, null, request.Allergies, null, null, null),
            "update_chronic_diseases" => new HealthArchiveUpdateRequest(null, null, null, null, null, request.ChronicDiseases, null),
            "update_diet_restrictions" => new HealthArchiveUpdateRequest(null, null, null, null, request.DietRestrictions, null, null),
            _ => null
        };

        if (scopedRequest == null)
            return new { success = false, message = $"未知档案操作: {action}" };

        Apply(current, scopedRequest);
        current.UpdatedAt = DateTime.UtcNow;
        await _archives.SaveChangesAsync(ct);
        return new { success = true };
    }

    private async Task<HealthArchive> GetOrCreateEntityAsync(Guid userId, CancellationToken ct)
    {
        var archive = await _archives.GetByUserIdAsync(userId, ct);
        if (archive != null) return archive;

        archive = new HealthArchive { Id = Guid.NewGuid(), UserId = userId, UpdatedAt = DateTime.UtcNow };
        await _archives.AddAsync(archive, ct);
        return archive;
    }

    private static void Apply(HealthArchive archive, HealthArchiveUpdateRequest request)
    {
        if (request.Diagnosis != null) archive.Diagnosis = request.Diagnosis;
        if (request.SurgeryType != null) archive.SurgeryType = request.SurgeryType;
        if (request.SurgeryDate.HasValue) archive.SurgeryDate = request.SurgeryDate.Value;
        if (request.Allergies != null) archive.Allergies = request.Allergies.ToList();
        if (request.DietRestrictions != null) archive.DietRestrictions = request.DietRestrictions.ToList();
        if (request.ChronicDiseases != null) archive.ChronicDiseases = request.ChronicDiseases.ToList();
        if (request.FamilyHistory != null) archive.FamilyHistory = request.FamilyHistory;
    }

    private static object ToAiResult(HealthArchiveDto archive) => new
    {
        found = true,
        archive.Diagnosis,
        archive.SurgeryType,
        SurgeryDate = archive.SurgeryDate?.ToString("yyyy-MM-dd"),
        archive.Allergies,
        archive.DietRestrictions,
        archive.ChronicDiseases,
        archive.FamilyHistory,
    };

    private static HealthArchiveDto ToDto(HealthArchive archive) => new(
        archive.Id,
        archive.UserId,
        archive.Diagnosis,
        archive.SurgeryType,
        archive.SurgeryDate,
        archive.Allergies,
        archive.DietRestrictions,
        archive.ChronicDiseases,
        archive.FamilyHistory,
        archive.UpdatedAt);
}