using CommunityToolkit.Mvvm.ComponentModel;
using HC_APTBS.Models;
using HC_APTBS.Services;

namespace HC_APTBS.ViewModels
{
    /// <summary>
    /// ViewModel for the three manual pump control sliders: FBKW (advance), ME (quantity),
    /// and PreIn (pre-injection quantity).  Each slider change calls
    /// <see cref="IBenchService.SetPumpControlValue"/> to update the CAN bus.
    /// </summary>
    public sealed partial class PumpControlViewModel : ObservableObject
    {
        private readonly IBenchService _bench;

        /// <summary>
        /// When true, suppress forwarding slider changes to the bench service.
        /// Used during programmatic updates to avoid re-entrant CAN sends.
        /// </summary>
        private bool _suppressSend;

        // ── FBKW (Advance Control) ───────────────────────────────────────────────

        /// <summary>Current FBKW slider value.</summary>
        [ObservableProperty] private double _fbkwValue;

        /// <summary>FBKW slider minimum.</summary>
        [ObservableProperty] private double _fbkwMin;

        /// <summary>FBKW slider maximum.</summary>
        [ObservableProperty] private double _fbkwMax = 100;

        /// <summary>FBKW slider tick frequency / step.</summary>
        [ObservableProperty] private double _fbkwStep = 10;

        // ── ME (Quantity Control) ─────────────────────────────────────────────────

        /// <summary>Current ME slider value.</summary>
        [ObservableProperty] private double _meValue;

        /// <summary>ME slider minimum.</summary>
        [ObservableProperty] private double _meMin;

        /// <summary>ME slider maximum.</summary>
        [ObservableProperty] private double _meMax = 100;

        /// <summary>ME slider tick frequency / step.</summary>
        [ObservableProperty] private double _meStep = 10;

        // ── PreIn (Pre-injection Quantity) ────────────────────────────────────────

        /// <summary>Current PreIn slider value.</summary>
        [ObservableProperty] private double _preInValue;

        /// <summary>PreIn slider minimum.</summary>
        [ObservableProperty] private double _preInMin;

        /// <summary>PreIn slider maximum.</summary>
        [ObservableProperty] private double _preInMax = 100;

        /// <summary>PreIn slider tick frequency / step.</summary>
        [ObservableProperty] private double _preInStep = 10;

        // ── Visibility / enablement ───────────────────────────────────────────────

        /// <summary>True when the current pump supports pre-injection.</summary>
        [ObservableProperty] private bool _isPreInVisible;

        /// <summary>True when a pump is selected and CAN is connected.</summary>
        [ObservableProperty] private bool _isEnabled;

        // ── Constructor ───────────────────────────────────────────────────────────

        /// <summary>Creates the ViewModel wired to the bench service for CAN output.</summary>
        public PumpControlViewModel(IBenchService bench)
        {
            _bench = bench;
        }

        // ── Property-changed callbacks → CAN send ─────────────────────────────────

        partial void OnFbkwValueChanged(double value)
        {
            if (!_suppressSend)
                _bench.SetPumpControlValue(PumpParameterNames.Fbkw, value);
        }

        partial void OnMeValueChanged(double value)
        {
            if (!_suppressSend)
                _bench.SetPumpControlValue(PumpParameterNames.Me, value);
        }

        partial void OnPreInValueChanged(double value)
        {
            if (!_suppressSend)
                _bench.SetPumpControlValue(PumpParameterNames.PreIn, value);
        }

        // ── Public API ────────────────────────────────────────────────────────────

        /// <summary>
        /// Called when the test executor sets a pump parameter value.
        /// Auto-expands slider min/max if the value exceeds the current range.
        /// Must be called on the UI thread.
        /// </summary>
        public void SetValueFromTest(string paramName, double value)
        {
            _suppressSend = true;
            try
            {
                switch (paramName)
                {
                    case PumpParameterNames.Me:
                        if (value > MeMax) MeMax = value;
                        else if (value < MeMin) MeMin = value;
                        MeValue = value;
                        break;
                    case PumpParameterNames.Fbkw:
                        if (value > FbkwMax) FbkwMax = value;
                        else if (value < FbkwMin) FbkwMin = value;
                        FbkwValue = value;
                        break;
                    case PumpParameterNames.PreIn:
                        if (value > PreInMax) PreInMax = value;
                        else if (value < PreInMin) PreInMin = value;
                        PreInValue = value;
                        break;
                }
            }
            finally
            {
                _suppressSend = false;
            }
        }

        /// <summary>Resets all slider values to zero and restores default min/max/step.</summary>
        public void Reset()
        {
            _suppressSend = true;
            try
            {
                FbkwValue = 0; FbkwMin = 0; FbkwMax = 100; FbkwStep = 10;
                MeValue   = 0; MeMin   = 0; MeMax   = 100; MeStep   = 10;
                PreInValue = 0; PreInMin = 0; PreInMax = 100; PreInStep = 10;
            }
            finally
            {
                _suppressSend = false;
            }
        }
    }
}