using Microsoft.AspNetCore.Mvc;


/// <summary>
/// Encounter retrieval, status transitions, and clinical timeline.
/// </summary>
[ApiController]
[Route("api/v1/encounters")]
[Produces("application/json")]
public class EncountersController : ControllerBase
{
    private readonly IEncounterService _encounters;

    public EncountersController(IEncounterService encounters) => _encounters = encounters;

    /// <summary>
    /// Gets an encounter with patient, recent observations, and open alerts.
    /// </summary>
    /// <param name="id">Encounter id.</param>
    /// <returns>The encounter with related data.</returns>
    [HttpGet("{id:guid}")]
    [ProducesResponseType(typeof(ApiResponse<Encounter>), StatusCodes.Status200OK)]
    [ProducesResponseType(typeof(ApiResponse<object>), StatusCodes.Status404NotFound)]
    public async Task<IActionResult> Get(Guid id)
    {
        var encounter = await _encounters.GetByIdAsync(id);
        return Ok(ApiResponse<Encounter>.Ok(encounter));
    }

    /// <summary>
    /// Transitions an encounter to a new status via the encounter state machine.
    /// </summary>
    /// <param name="id">Encounter id.</param>
    /// <param name="req">Target status.</param>
    /// <returns>The encounter id and new status.</returns>
    [HttpPatch("{id:guid}/status")]
    [ProducesResponseType(typeof(ApiResponse<object>), StatusCodes.Status200OK)]
    [ProducesResponseType(typeof(ApiResponse<object>), StatusCodes.Status404NotFound)]
    [ProducesResponseType(typeof(ApiResponse<object>), StatusCodes.Status409Conflict)]
    public async Task<IActionResult> TransitionStatus(Guid id, [FromBody] TransitionStatusRequest req)
    {
        var result = await _encounters.TransitionStatusAsync(id, req.Status);
        return Ok(ApiResponse<object>.Ok(new { encounterId = result.EncounterId, newStatus = result.NewStatus }));
    }

    /// <summary>
    /// Returns a merged chronological timeline of observations and alerts for an encounter.
    /// </summary>
    /// <param name="id">Encounter id.</param>
    /// <returns>Ordered timeline events.</returns>
    [HttpGet("{id:guid}/timeline")]
    [ProducesResponseType(typeof(ApiResponse<object>), StatusCodes.Status200OK)]
    [ProducesResponseType(typeof(ApiResponse<object>), StatusCodes.Status404NotFound)]
    public async Task<IActionResult> Timeline(Guid id)
    {
        var timeline = await _encounters.GetTimelineAsync(id);
        return Ok(ApiResponse<object>.Ok(timeline));
    }
}