/*
 
  This Source Code Form is subject to the terms of the Mozilla Public
  License, v. 2.0. If a copy of the MPL was not distributed with this
  file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
  Copyright (C) 2009-2013 Michael Möller <mmoeller@openhardwaremonitor.org>
	
*/

using System;
using System.Collections.Generic;
using System.Drawing;
using System.Linq;
using System.Windows.Forms;
using OpenHardwareMonitor.Hardware;
using OxyPlot;
using OxyPlot.Axes;
using OxyPlot.WindowsForms;
using OxyPlot.Series;
using OpenHardwareMonitor.Collections;

namespace OpenHardwareMonitor.GUI {
  public class PlotPanel : UserControl {

    private readonly PersistentSettings settings;
    private readonly UnitManager unitManager;

    private readonly Plot plot;
    private readonly PlotModel model;
    private readonly TimeSpanAxis timeAxis = new TimeSpanAxis();
    private readonly SortedDictionary<SensorType, LinearAxis> axes =
      new SortedDictionary<SensorType, LinearAxis>();

    private UserOption stackedAxes;

    private DateTime now;

    public PlotPanel(PersistentSettings settings, UnitManager unitManager) {
      this.settings = settings;
      this.unitManager = unitManager;

      this.model = CreatePlotModel();

      this.plot = new Plot();
      this.plot.Dock = DockStyle.Fill;
      this.plot.Model = model;
      this.plot.BackColor = Color.White;
      this.plot.ContextMenu = CreateMenu();

      UpdateAxesPosition();

      this.SuspendLayout();
      this.Controls.Add(plot);
      this.ResumeLayout(true);
    }

    public void SetCurrentSettings() {
      settings.SetValue("plotPanel.MinTimeSpan", (float)timeAxis.ViewMinimum);
      settings.SetValue("plotPanel.MaxTimeSpan", (float)timeAxis.ViewMaximum);

      foreach (var axis in axes.Values) {
        settings.SetValue("plotPanel.Min" + axis.Key, (float)axis.ViewMinimum);
        settings.SetValue("plotPanel.Max" + axis.Key, (float)axis.ViewMaximum);
      }
    }

    private ContextMenu CreateMenu() {
      ContextMenu menu = new ContextMenu();

      MenuItem stackedAxesMenuItem = new MenuItem("Stacked Axes");
      stackedAxes = new UserOption("stackedAxes", true,
        stackedAxesMenuItem, settings);
      stackedAxes.Changed += (sender, e) => {
        UpdateAxesPosition();
        InvalidatePlot();
      };
      menu.MenuItems.Add(stackedAxesMenuItem);

      MenuItem timeWindow = new MenuItem("Time Window");
      MenuItem[] timeWindowMenuItems =
        { new MenuItem("Auto", 
            (s, e) => { timeAxis.Zoom(0, double.NaN); InvalidatePlot(); }),
          new MenuItem("5 min", 
            (s, e) => { timeAxis.Zoom(0, 5 * 60); InvalidatePlot(); }),
          new MenuItem("10 min", 
            (s, e) => { timeAxis.Zoom(0, 10 * 60); InvalidatePlot(); }),
          new MenuItem("20 min", 
            (s, e) => { timeAxis.Zoom(0, 20 * 60); InvalidatePlot(); }),
          new MenuItem("30 min", 
            (s, e) => { timeAxis.Zoom(0, 30 * 60); InvalidatePlot(); }),
          new MenuItem("45 min", 
            (s, e) => { timeAxis.Zoom(0, 45 * 60); InvalidatePlot(); }),
          new MenuItem("1 h", 
            (s, e) => { timeAxis.Zoom(0, 60 * 60); InvalidatePlot(); }),
          new MenuItem("1.5 h", 
            (s, e) => { timeAxis.Zoom(0, 1.5 * 60 * 60); InvalidatePlot(); }),
          new MenuItem("2 h", 
            (s, e) => { timeAxis.Zoom(0, 2 * 60 * 60); InvalidatePlot(); }),
          new MenuItem("3 h", 
            (s, e) => { timeAxis.Zoom(0, 3 * 60 * 60); InvalidatePlot(); }),
          new MenuItem("6 h", 
            (s, e) => { timeAxis.Zoom(0, 6 * 60 * 60); InvalidatePlot(); }),
          new MenuItem("12 h", 
            (s, e) => { timeAxis.Zoom(0, 12 * 60 * 60); InvalidatePlot(); }),
          new MenuItem("24 h", 
            (s, e) => { timeAxis.Zoom(0, 24 * 60 * 60); InvalidatePlot(); }) };
      foreach (MenuItem mi in timeWindowMenuItems)
        timeWindow.MenuItems.Add(mi);
      menu.MenuItems.Add(timeWindow);

      return menu;
    }

    private PlotModel CreatePlotModel() {

      timeAxis.Position = AxisPosition.Bottom;
      timeAxis.MajorGridlineStyle = LineStyle.Solid;
      timeAxis.MajorGridlineThickness = 1;
      timeAxis.MajorGridlineColor = OxyColor.FromRgb(192, 192, 192);
      timeAxis.MinorGridlineStyle = LineStyle.Solid;
      timeAxis.MinorGridlineThickness = 1;
      timeAxis.MinorGridlineColor = OxyColor.FromRgb(232, 232, 232);
      timeAxis.StartPosition = 1;
      timeAxis.EndPosition = 0;
      timeAxis.MinimumPadding = 0;
      timeAxis.MaximumPadding = 0;
      timeAxis.AbsoluteMinimum = 0;
      timeAxis.Minimum = 0;
      timeAxis.AbsoluteMaximum = 24 * 60 * 60;
      timeAxis.Zoom(
        settings.GetValue("plotPanel.MinTimeSpan", 0.0f),
        settings.GetValue("plotPanel.MaxTimeSpan", 10.0f * 60));
      timeAxis.StringFormat = "h:mm";

      var units = new Dictionary<SensorType, string>();
      units.Add(SensorType.Voltage, "V");
      units.Add(SensorType.Clock, "MHz");
      units.Add(SensorType.Temperature, "°C");
      units.Add(SensorType.Load, "%");
      units.Add(SensorType.Fan, "RPM");
      units.Add(SensorType.Flow, "L/h");
      units.Add(SensorType.Control, "%");
      units.Add(SensorType.Level, "%");
      units.Add(SensorType.Factor, "1");
      units.Add(SensorType.Power, "W");
      units.Add(SensorType.Data, "GB");

      foreach (SensorType type in Enum.GetValues(typeof(SensorType))) {
        var axis = new LinearAxis();
        axis.Position = AxisPosition.Left;
        axis.MajorGridlineStyle = LineStyle.Solid;
        axis.MajorGridlineThickness = 1;
        axis.MajorGridlineColor = timeAxis.MajorGridlineColor;
        axis.MinorGridlineStyle = LineStyle.Solid;
        axis.MinorGridlineThickness = 1;
        axis.MinorGridlineColor = timeAxis.MinorGridlineColor;
        axis.AxislineStyle = LineStyle.Solid;
        axis.Title = type.ToString();
        axis.Key = type.ToString();

        axis.Zoom(
          settings.GetValue("plotPanel.Min" + axis.Key, float.NaN),
          settings.GetValue("plotPanel.Max" + axis.Key, float.NaN));

        if (units.ContainsKey(type))
          axis.Unit = units[type];
        axes.Add(type, axis);
      }

      var model = new PlotModel();
      model.Axes.Add(timeAxis);
      foreach (var axis in axes.Values)
        model.Axes.Add(axis);
      model.PlotMargins = new OxyThickness(0);
      model.IsLegendVisible = false;

      return model;
    }

    public void SetSensors(List<ISensor> sensors,
      IDictionary<ISensor, Color> colors) {
      this.model.Series.Clear();

      ListSet<SensorType> types = new ListSet<SensorType>();

      foreach (ISensor sensor in sensors) {
        var series = new LineSeries();
        if (sensor.SensorType == SensorType.Temperature) {
          series.ItemsSource = sensor.Values.Select(value => new DataPoint {
            X = (now - value.Time).TotalSeconds,
            Y = unitManager.TemperatureUnit == TemperatureUnit.Celsius ? 
              value.Value : UnitManager.CelsiusToFahrenheit(value.Value).Value
          });
        } else {
          series.ItemsSource = sensor.Values.Select(value => new DataPoint {
            X = (now - value.Time).TotalSeconds, Y = value.Value
          });
        }
        series.Color = colors[sensor].ToOxyColor();
        series.StrokeThickness = 1;
        series.YAxisKey = axes[sensor.SensorType].Key;
        series.Title = sensor.Hardware.Name + " " + sensor.Name;
        this.model.Series.Add(series);

        types.Add(sensor.SensorType);
      }

      foreach (var pair in axes.Reverse()) {
        var axis = pair.Value;
        var type = pair.Key;
        axis.IsAxisVisible = types.Contains(type);
      } 

      UpdateAxesPosition();
      InvalidatePlot();
    }

    private void UpdateAxesPosition() {
      if (stackedAxes.Value) {
        var count = axes.Values.Count(axis => axis.IsAxisVisible);
        var start = 0.0;
        foreach (var pair in axes.Reverse()) {
          var axis = pair.Value;
          var type = pair.Key;
          axis.StartPosition = start;
          var delta = axis.IsAxisVisible ? 1.0 / count : 0;
          start += delta;
          axis.EndPosition = start;
          axis.PositionTier = 0;
          axis.MajorGridlineStyle = LineStyle.Solid;
          axis.MinorGridlineStyle = LineStyle.Solid;   
        }
      } else {
        var tier = 0;
        foreach (var pair in axes.Reverse()) {
          var axis = pair.Value;
          var type = pair.Key;
          if (axis.IsAxisVisible) {
            axis.StartPosition = 0;
            axis.EndPosition = 1;
            axis.PositionTier = tier;
            tier++;
          } else {
            axis.StartPosition = 0;
            axis.EndPosition = 0;
            axis.PositionTier = 0;
          }
          axis.MajorGridlineStyle = LineStyle.None;
          axis.MinorGridlineStyle = LineStyle.None;          
        }
      }

    }

    public void InvalidatePlot() {
      this.now = DateTime.UtcNow;

      foreach (var pair in axes) {
        var axis = pair.Value;
        var type = pair.Key;
        if (type == SensorType.Temperature)
          axis.Unit = unitManager.TemperatureUnit == TemperatureUnit.Celsius ?
          "°C" : "°F";
      }

      this.plot.InvalidatePlot(true);
    }

  }
}