using adas_core.Application.Services.Interfaces;
using adas_core.Domain.Enums;
using adas_core.Domain.Models;
using adas_core.Domain.Models.Pumps;
using MongoDB.Bson;

namespace adas_core.Application.Services;

/// <summary>
/// Provides the default implementation of the <see cref="ICalculatedObservations"/> interface.
/// </summary>
public class DefaultCalculatedObservations : ICalculatedObservations
{
    /// <summary>
    /// Asynchronously calculates medicine observations for a patient based on their currently active medicines.
    /// </summary>
    /// <param name="activeMedicines">The list of medicines currently active for the patient, used as the basis for the observation calculation.</param>
    /// <param name="patientId">The identifier of the patient whose medicine observations are being calculated.</param>
    public Task CalculateMedicineObservation(List<Medicine> activeMedicines, ObjectId patientId)
        {
            return Task.CompletedTask;
        }

    /// <summary>
    /// Calculates the active bolus for the specified patient.
    /// </summary>
    /// <param name="patientId">The unique identifier of the patient whose active bolus is being calculated.</param>
    public Task CalculateActiveBolus(ObjectId patientId)
        {
            return Task.CompletedTask;
        }

    /// <summary>
    /// Returns the provided patient observation as a completed task, preserving the original instance for further processing.
    /// </summary>
    /// <param name="obs">The patient observation to map.</param>
    /// <param name="onlyByName">A flag indicating whether mapping should be performed by name only.</param>
    /// <returns>A completed <see cref="Task{T}"/> containing the provided observation.</returns>
    public Task<T?> Map<T>(T obs, bool onlyByName) where T : BasePatientObservation
        {
            return Task.FromResult(obs)!;
        }

    /// <summary>
    /// Maps a <see cref="PatientTreatment"/> instance to a completed task, returning the provided treatment unchanged.
    /// </summary>
    /// <param name="treatment">The patient treatment to map.</param>
    /// <returns>A <see cref="Task{PatientTreatment}"/> that completes with the supplied <paramref name="treatment"/>.</returns>
    public Task<PatientTreatment> Map(PatientTreatment treatment)
        {
            return Task.FromResult(treatment);
        }

    /// <summary>
    /// Retrieves the active treatments associated with the specified patient identifier.
    /// Returns an empty collection, typically serving as a stub or fallback when no treatments are available.
    /// </summary>
    /// <param name="id">The unique identifier of the patient whose active treatments are being retrieved.</param>
    /// <returns>A task representing the asynchronous operation, containing an enumerable collection of the patient's active treatments, or an empty collection if none are found.</returns>
    public Task<IEnumerable<PatientTreatment?>> GetActiveTreatmentsByPatient(ObjectId id)
        {
            return Task.FromResult<IEnumerable<PatientTreatment?>>(new List<PatientTreatment?>());
        }

    /// <summary>
    /// Returns the provided patient diagnosis as-is, wrapped in a completed task for asynchronous compatibility.
    /// </summary>
    /// <param name="diagnosis">The patient diagnosis to map.</param>
    /// <returns>A task that represents the asynchronous operation, containing the provided patient diagnosis.</returns>
    public Task<PatientDiagnosis> Map(PatientDiagnosis diagnosis)
        {
            return Task.FromResult(diagnosis);
        }

    /// <summary>
    /// Maps a <see cref="PumpObservation"/> instance to a target <see cref="PumpObservation"/> representation asynchronously.
    /// </summary>
    /// <param name="pumpObservation">The source <see cref="PumpObservation"/> to be mapped.</param>
    /// <returns>A task that represents the asynchronous mapping operation, containing the resulting <see cref="PumpObservation"/>.</returns>
    /// <exception cref="NotImplementedException">Thrown when the method is invoked, as the mapping logic has not been implemented yet.</exception>
    public Task<PumpObservation> Map(PumpObservation pumpObservation)
        {
            throw new NotImplementedException();
        }

    /// <summary>
    /// Processes a new patient observation to address potential time inconsistency with the previous observation, returning the observation unchanged.
    /// </summary>
    /// <param name="newObservation">The new patient observation to evaluate for time consistency with the prior observation.</param>
    /// <returns>A task that represents the asynchronous operation, containing the provided patient observation.</returns>
    public Task<PatientObservation?> FixTimeInconsistencyWithLast(PatientObservation newObservation)
        {
            return Task.FromResult<PatientObservation?>(newObservation);
        }

    /// <summary>
    /// Performs a pre-mapping step on a list of patient observations before further processing, returning the list unchanged.
    /// </summary>
    /// <param name="listToInsert">The list of patient observations to be pre-mapped.</param>
    /// <returns>A completed task containing the provided list of patient observations.</returns>
    public Task<List<PatientObservation>> PreMapList(List<PatientObservation> listToInsert)
        {
            return Task.FromResult(listToInsert);
        }

    /// <summary>
    /// Maps a source alarm onto a <see cref="PatientObservation"/> and returns the observation wrapped in a completed task.
    /// In the current implementation, the observation is returned as-is without applying the supplied alarm.
    /// </summary>
    /// <param name="obs">The patient observation to be returned by the mapping.</param>
    /// <param name="alarmToInsert">The patient observation alarm intended to be associated with the observation.</param>
    /// <returns>A completed <see cref="Task{TResult}"/> containing the <see cref="PatientObservation"/>.</returns>
    public Task<PatientObservation> MapSourceAlarm(PatientObservation obs, PatientObservationAlarm alarmToInsert)
        {
            return Task.FromResult(obs);
        }

    /// <summary>
    /// Sends an alarm notification based on the provided patient observation, associated name, and optional alarm code.
    /// </summary>
    /// <param name="obs">The patient observation that triggers the alarm.</param>
    /// <param name="name">The name associated with the alarm being sent.</param>
    /// <param name="code">The optional alarm code that categorizes the type of alarm; may be null when no specific code applies.</param>
    /// <exception cref="NotImplementedException">Thrown in all cases, as the method has not been implemented yet.</exception>
    public Task SendAlarm(PatientObservation obs, string name, AlarmEnum.Name? code)
        {
            throw new NotImplementedException();
        }
}