using System.ComponentModel;
using VoiceCat.App.Models;
using VoiceCat.Interop;

namespace VoiceCat.App.Forms;

/// <summary>
/// Edits audio input settings: device selection, transmission mode (VAD/PTT/always-on),
/// VAD sensitivity, mic gain, and PTT key. Changes are applied live to the client for
/// immediate feedback; Cancel reverts them.
/// </summary>
public sealed class AudioSettingsForm : Form
{
    private readonly VoiceCatClient _client;
    private readonly VoiceSettings _settings;
    private readonly uint _micStreamId;

    // Snapshot of original values so Cancel can restore them
    private readonly string? _origDeviceId;
    private readonly VcInputMode _origMode;
    private readonly int _origVadSlider;
    private readonly int _origMicGain;
    private readonly Keys _origPttKey;

    private readonly ComboBox _cboDevice;
    private readonly Button _btnRefresh;
    private readonly RadioButton _radioVad;
    private readonly RadioButton _radioPtt;
    private readonly RadioButton _radioAlwaysOn;
    private readonly Label _lblPttKey;
    private readonly Button _btnChangePtt;
    private readonly Label _lblSensitivity;
    private readonly TrackBar _trkVad;
    private readonly TrackBar _trkGain;

    private Keys _pttKey;

    public AudioSettingsForm(VoiceCatClient client, VoiceSettings settings, uint micStreamId)
    {
        _client = client;
        _settings = settings;
        _micStreamId = micStreamId;
        _pttKey = (Keys)settings.PttKey;

        _origDeviceId = settings.InputDeviceId;
        _origMode = (VcInputMode)settings.InputMode;
        _origVadSlider = settings.VadThresholdSlider;
        _origMicGain = settings.MicGain;
        _origPttKey = _pttKey;

        Text = "Audio settings";
        FormBorderStyle = FormBorderStyle.FixedDialog;
        MaximizeBox = false;
        MinimizeBox = false;
        StartPosition = FormStartPosition.CenterParent;
        AutoScaleMode = AutoScaleMode.Font;
        ClientSize = new Size(420, 370);

        // ── Device row ────────────────────────────────────────────────────────
        var lblDevice = new Label
        {
            Text = "Input &device:",
            Location = new Point(12, 16),
            AutoSize = true,
        };

        _cboDevice = new ComboBox
        {
            Location = new Point(12, 36),
            Width = 300,
            DropDownStyle = ComboBoxStyle.DropDownList,
            DisplayMember = "Name",
            ValueMember = "Id",
            AccessibleName = "Input device",
            AccessibleDescription = "Select which microphone or audio input device to use.",
        };
        _cboDevice.SelectedIndexChanged += CboDevice_SelectedIndexChanged;

        _btnRefresh = new Button
        {
            Text = "&Refresh",
            Location = new Point(320, 34),
            Size = new Size(80, 26),
        };
        _btnRefresh.Click += (_, _) => LoadDevices();

        // ── Transmission mode ─────────────────────────────────────────────────
        var lblMode = new Label
        {
            Text = "Transmission mode:",
            Location = new Point(12, 76),
            AutoSize = true,
        };

        _radioVad = new RadioButton
        {
            Text = "&Voice activation",
            Location = new Point(20, 96),
            AutoSize = true,
        };
        _radioVad.CheckedChanged += RadioMode_CheckedChanged;

        _lblSensitivity = new Label
        {
            Text = "Sensitivity:",
            Location = new Point(36, 122),
            AutoSize = true,
        };
        _trkVad = new TrackBar
        {
            Location = new Point(36, 140),
            Size = new Size(200, 45),
            Minimum = 1,
            Maximum = 100,
            TickFrequency = 10,
            SmallChange = 1,
            LargeChange = 10,
            Value = Math.Clamp(settings.VadThresholdSlider, 1, 100),
        };
        _trkVad.AccessibleName = "VAD sensitivity";
        _trkVad.AccessibleDescription =
            "Voice detection sensitivity. Higher = more sensitive. Range 1–100.";
        _trkVad.Scroll += TrkVad_Scroll;

        _radioPtt = new RadioButton
        {
            Text = "&Push to talk",
            Location = new Point(20, 192),
            AutoSize = true,
        };
        _radioPtt.CheckedChanged += RadioMode_CheckedChanged;

        _lblPttKey = new Label
        {
            Location = new Point(140, 194),
            AutoSize = true,
        };

        _btnChangePtt = new Button
        {
            Text = "Change key...",
            Location = new Point(200, 189),
            Size = new Size(105, 26),
        };
        _btnChangePtt.Click += BtnChangePtt_Click;

        _radioAlwaysOn = new RadioButton
        {
            Text = "A&lways on",
            Location = new Point(20, 224),
            AutoSize = true,
        };
        _radioAlwaysOn.CheckedChanged += RadioMode_CheckedChanged;

        // ── Mic gain ──────────────────────────────────────────────────────────
        var lblGain = new Label
        {
            Text = "Microphone &volume:",
            Location = new Point(12, 268),
            AutoSize = true,
        };
        _trkGain = new TrackBar
        {
            Location = new Point(12, 288),
            Size = new Size(200, 45),
            Minimum = 0,
            Maximum = 300,
            TickFrequency = 25,
            SmallChange = 5,
            LargeChange = 25,
            Value = Math.Clamp(settings.MicGain, 0, 300),
        };
        _trkGain.AccessibleName = "Microphone volume";
        _trkGain.AccessibleDescription =
            "Boost a quiet microphone. 100 is unity gain; range 0–300 percent.";
        _trkGain.Scroll += TrkGain_Scroll;

        // ── OK / Cancel ───────────────────────────────────────────────────────
        var btnOk = new Button
        {
            Text = "&OK",
            DialogResult = DialogResult.OK,
            Location = new Point(228, 334),
            Size = new Size(80, 27),
        };
        var btnCancel = new Button
        {
            Text = "&Cancel",
            DialogResult = DialogResult.Cancel,
            Location = new Point(316, 334),
            Size = new Size(80, 27),
        };

        AcceptButton = btnOk;
        CancelButton = btnCancel;

        btnOk.Click += (_, _) =>
        {
            _settings.Save();
        };
        FormClosing += AudioSettingsForm_FormClosing;

        Controls.AddRange([
            lblDevice, _cboDevice, _btnRefresh,
            lblMode, _radioVad, _lblSensitivity, _trkVad,
            _radioPtt, _lblPttKey, _btnChangePtt, _radioAlwaysOn,
            lblGain, _trkGain,
            btnOk, btnCancel,
        ]);

        // Apply saved mode (fires RadioMode_CheckedChanged which sets visibility)
        switch ((VcInputMode)settings.InputMode)
        {
            case VcInputMode.PushToTalk: _radioPtt.Checked = true; break;
            case VcInputMode.AlwaysOn:   _radioAlwaysOn.Checked = true; break;
            default:                     _radioVad.Checked = true; break;
        }

        LoadDevices();
    }

    private void LoadDevices()
    {
        string? currentId = (_cboDevice.SelectedItem as DeviceInfo)?.Id ?? _settings.InputDeviceId;

        var devices = _client.ListDevices(VcDeviceKind.Input);
        _cboDevice.SelectedIndexChanged -= CboDevice_SelectedIndexChanged;
        _cboDevice.DataSource = new BindingList<DeviceInfo>(devices);
        _cboDevice.SelectedIndexChanged += CboDevice_SelectedIndexChanged;

        // Try to restore previous selection
        int idx = -1;
        if (currentId is not null)
            idx = devices.FindIndex(d => d.Id == currentId);
        if (idx < 0)
            idx = devices.FindIndex(d => d.IsDefault);
        _cboDevice.SelectedIndex = idx >= 0 ? idx : (devices.Count > 0 ? 0 : -1);
    }

    private void CboDevice_SelectedIndexChanged(object? sender, EventArgs e)
    {
        if (_cboDevice.SelectedItem is not DeviceInfo dev) return;
        _settings.InputDeviceId = dev.IsDefault ? null : dev.Id;
        if (_micStreamId != 0)
            _client.SetInputDevice(_micStreamId, dev.IsDefault ? null : dev.Id);
    }

    private void RadioMode_CheckedChanged(object? sender, EventArgs e)
    {
        var mode = CurrentMode();
        bool isVad = mode == VcInputMode.VoiceActivation;
        bool isPtt = mode == VcInputMode.PushToTalk;

        _lblSensitivity.Visible = isVad;
        _trkVad.Visible = isVad;
        _lblPttKey.Visible = isPtt;
        _btnChangePtt.Visible = isPtt;
        UpdatePttKeyLabel();

        _settings.InputMode = (int)mode;
        if (_micStreamId != 0)
        {
            _client.SetInputMode(mode);
            if (isVad) _client.SetVadThreshold(VadThresholdFromSlider());
            if (isPtt) _client.SetPushToTalk(false);
        }
    }

    private void TrkVad_Scroll(object? sender, EventArgs e)
    {
        _settings.VadThresholdSlider = _trkVad.Value;
        if (_micStreamId != 0 && CurrentMode() == VcInputMode.VoiceActivation)
            _client.SetVadThreshold(VadThresholdFromSlider());
    }

    private void TrkGain_Scroll(object? sender, EventArgs e)
    {
        _settings.MicGain = _trkGain.Value;
        if (_micStreamId != 0)
            _client.SetInputGain(_trkGain.Value / 100f);
    }

    private void BtnChangePtt_Click(object? sender, EventArgs e)
    {
        using var dlg = new PttKeyCaptureDialog(_pttKey);
        if (dlg.ShowDialog(this) == DialogResult.OK)
        {
            _pttKey = dlg.CapturedKey;
            _settings.PttKey = (int)_pttKey;
            UpdatePttKeyLabel();
        }
    }

    private void AudioSettingsForm_FormClosing(object? sender, FormClosingEventArgs e)
    {
        if (DialogResult == DialogResult.OK) return;

        // Cancel: restore originals to settings and live client
        _settings.InputDeviceId = _origDeviceId;
        _settings.InputMode = (int)_origMode;
        _settings.VadThresholdSlider = _origVadSlider;
        _settings.MicGain = _origMicGain;
        _settings.PttKey = (int)_origPttKey;

        if (_micStreamId != 0)
        {
            _client.SetInputDevice(_micStreamId, _origDeviceId);
            _client.SetInputMode(_origMode);
            if (_origMode == VcInputMode.VoiceActivation)
                _client.SetVadThreshold(0.1f * (1f - (_origVadSlider - 1f) / 99f));
            _client.SetInputGain(_origMicGain / 100f);
        }
    }

    private void UpdatePttKeyLabel() =>
        _lblPttKey.Text = $"({_pttKey})";

    private VcInputMode CurrentMode() =>
        _radioPtt.Checked ? VcInputMode.PushToTalk :
        _radioAlwaysOn.Checked ? VcInputMode.AlwaysOn :
        VcInputMode.VoiceActivation;

    private float VadThresholdFromSlider() =>
        0.1f * (1f - (_trkVad.Value - 1f) / 99f);
}