/*
 * Copyright (c) 2006 Sean C. Rhea (srhea@srhea.net)
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 2 of the License, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc., 51
 * Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */

#include "PowerHist.h"
#include "MainWindow.h"
#include "RideItem.h"
#include "IntervalItem.h"
#include "RideFile.h"
#include "Settings.h"
#include "Zones.h"

#include <assert.h>
#include <qpainter.h>
#include <qwt_plot_curve.h>
#include <qwt_plot_grid.h>
#include <qwt_plot_zoomer.h>
#include <qwt_scale_engine.h>
#include <qwt_text.h>
#include <qwt_legend.h>
#include <qwt_data.h>

class penTooltip: public QwtPlotZoomer
{
    public:
         penTooltip(QwtPlotCanvas *canvas):
             QwtPlotZoomer(canvas)
         {
                 // With some versions of Qt/Qwt, setting this to AlwaysOn
                 // causes an infinite recursion.
                 //setTrackerMode(AlwaysOn);
                 setTrackerMode(AlwaysOff);
         }

         virtual QwtText trackerText(const QwtDoublePoint &pos) const
         {
                 QColor bg(Qt::white);
         #if QT_VERSION >= 0x040300
                     bg.setAlpha(200);
             #endif

                     QwtText text = QString("%1").arg((int)pos.x());
                     text.setBackgroundBrush( QBrush( bg ));
                     return text;
         }
 };





// define a background class to handle shading of power zones
// draws power zone bands IF zones are defined and the option
// to draw bonds has been selected
class PowerHistBackground: public QwtPlotItem
{
private:
    PowerHist *parent;

public:
    PowerHistBackground(PowerHist *_parent)
    {
        setZ(0.0);
	parent = _parent;
    }

    virtual int rtti() const
    {
        return QwtPlotItem::Rtti_PlotUserItem;
    }

    virtual void draw(QPainter *painter,
		      const QwtScaleMap &xMap, const QwtScaleMap &,
		      const QRect &rect) const
    {
	RideItem *rideItem = parent->rideItem;

	if (! rideItem)
	    return;

	const Zones *zones       = rideItem->zones;
	int zone_range     = rideItem->zoneRange();

	if (parent->shadeZones() && (zone_range >= 0)) {
	    QList <int> zone_lows = zones->getZoneLows(zone_range);
	    int num_zones = zone_lows.size();
	    if (num_zones > 0) {
		for (int z = 0; z < num_zones; z ++) {
		    QRect r = rect;

		    QColor shading_color =
			zoneColor(z, num_zones);
		    shading_color.setHsv(
					 shading_color.hue(),
					 shading_color.saturation() / 4,
					 shading_color.value()
					 );
		    r.setLeft(xMap.transform(zone_lows[z]));
		    if (z + 1 < num_zones)
			r.setRight(xMap.transform(zone_lows[z + 1]));
		    if (r.right() >= r.left())
			painter->fillRect(r, shading_color);
		}
	    }
	}
    }
};


// Zone labels are drawn if power zone bands are enabled, automatically
// at the center of the plot
class PowerHistZoneLabel: public QwtPlotItem
{
private:
    PowerHist *parent;
    int zone_number;
    double watts;
    QwtText text;

public:
    PowerHistZoneLabel(PowerHist *_parent, int _zone_number)
    {
	parent = _parent;
	zone_number = _zone_number;

	RideItem *rideItem = parent->rideItem;

	if (! rideItem)
	    return;

	const Zones *zones       = rideItem->zones;
	int zone_range     = rideItem->zoneRange();

	setZ(1.0 + zone_number / 100.0);

	// create new zone labels if we're shading
	if (parent->shadeZones() && (zone_range >= 0)) {
	    QList <int> zone_lows = zones->getZoneLows(zone_range);
	    QList <QString> zone_names = zones->getZoneNames(zone_range);
	    int num_zones = zone_lows.size();
	    assert(zone_names.size() == num_zones);
	    if (zone_number < num_zones) {
		watts =
		    (
		     (zone_number + 1 < num_zones) ?
		     0.5 * (zone_lows[zone_number] + zone_lows[zone_number + 1]) :
		     (
		      (zone_number > 0) ?
		      (1.5 * zone_lows[zone_number] - 0.5 * zone_lows[zone_number - 1]) :
		      2.0 * zone_lows[zone_number]
		      )
		     );

		text = QwtText(zone_names[zone_number]);
		text.setFont(QFont("Helvetica",24, QFont::Bold));
		QColor text_color = zoneColor(zone_number, num_zones);
		text_color.setAlpha(64);
		text.setColor(text_color);
	    }
	}

    }

    virtual int rtti() const
    {
        return QwtPlotItem::Rtti_PlotUserItem;
    }

    void draw(QPainter *painter,
	      const QwtScaleMap &xMap, const QwtScaleMap &,
	      const QRect &rect) const
    {
	if (parent->shadeZones()) {
	    int x = xMap.transform(watts);
	    int y = (rect.bottom() + rect.top()) / 2;

	    // the following code based on source for QwtPlotMarker::draw()
	    QRect tr(QPoint(0, 0), text.textSize(painter->font()));
	    tr.moveCenter(QPoint(y, -x));
	    painter->rotate(90);             // rotate text to avoid overlap: this needs to be fixed
	    text.draw(painter, tr);
	}
    }
};

PowerHist::PowerHist(MainWindow *mainWindow):
    selected(wattsShaded),
    rideItem(NULL),
    mainWindow(mainWindow),
    binw(20),
    withz(true),
    settings(NULL),
    unit(0),
    lny(false)
{

    boost::shared_ptr<QSettings> settings = GetApplicationSettings();

    unit = settings->value(GC_UNIT);

    useMetricUnits = (unit.toString() == "Metric");

    // create a background object for shading
    bg = new PowerHistBackground(this);
    bg->attach(this);

    setCanvasBackground(Qt::white);

    setParameterAxisTitle();
    setAxisTitle(yLeft, "Cumulative Time (minutes)");

    curve = new QwtPlotCurve("");
    curve->setStyle(QwtPlotCurve::Steps);
    curve->setRenderHint(QwtPlotItem::RenderAntialiased);
    QPen *pen = new QPen(Qt::black);
    pen->setWidth(2.0);
    curve->setPen(*pen);
    QColor brush_color = Qt::black;
    brush_color.setAlpha(64);
    curve->setBrush(brush_color);   // fill below the line
    delete pen;
    curve->attach(this);

    curveSelected = new QwtPlotCurve("");
    curveSelected->setStyle(QwtPlotCurve::Steps);
    curveSelected->setRenderHint(QwtPlotItem::RenderAntialiased);
    pen = new QPen(Qt::blue);
    pen->setWidth(2.0);
    curveSelected->setPen(*pen);
    brush_color = Qt::blue;
    brush_color.setAlpha(64);
    curveSelected->setBrush(brush_color);   // fill below the line
    delete pen;
    curveSelected->attach(this);

    grid = new QwtPlotGrid();
    grid->enableX(false);
    QPen gridPen;
    gridPen.setStyle(Qt::DotLine);
    grid->setPen(gridPen);
    grid->attach(this);

    zoneLabels = QList <PowerHistZoneLabel *>::QList();

    zoomer = new penTooltip(this->canvas());
}

PowerHist::~PowerHist() {
    delete bg;
    delete curve;
    delete curveSelected;
    delete grid;
}

// static const variables from PoweHist.h:
// discritized unit for smoothing
const double PowerHist::wattsDelta;
const double PowerHist::nmDelta;
const double PowerHist::hrDelta;
const double PowerHist::kphDelta;
const double PowerHist::cadDelta;

// digits for text entry validator
const int PowerHist::wattsDigits;
const int PowerHist::nmDigits;
const int PowerHist::hrDigits;
const int PowerHist::kphDigits;
const int PowerHist::cadDigits;

void
PowerHist::refreshZoneLabels()
{
    // delete any existing power zone labels
    if (zoneLabels.size()) {
	QListIterator<PowerHistZoneLabel *> i(zoneLabels);
	while (i.hasNext()) {
	    PowerHistZoneLabel *label = i.next();
	    label->detach();
	    delete label;
	}
    }
    zoneLabels.clear();

    if (! rideItem)
	return;

    if ((selected == wattsShaded) || (selected == wattsUnshaded)) {
	const Zones *zones = rideItem->zones;
	int zone_range = rideItem->zoneRange();

        // generate labels for existing zones
	if (zone_range >= 0) {
	    int num_zones = zones->numZones(zone_range);
	    for (int z = 0; z < num_zones; z ++) {
		PowerHistZoneLabel *label = new PowerHistZoneLabel(this, z);
		label->attach(this);
		zoneLabels.append(label);
	    }
	}
    }
}

void
PowerHist::recalc()
{
    QVector<unsigned int> *array;
    QVector<unsigned int> *selectedArray;
    int arrayLength = 0;
    double delta;

    // make sure the interval length is set
    if (dt <= 0)
	return;

    if ((selected == wattsShaded) ||
	(selected == wattsUnshaded)
	) {
	array = &wattsArray;
	delta = wattsDelta;
	arrayLength = wattsArray.size();
	selectedArray = &wattsSelectedArray;
    }
    else if (selected == nm) {
	array = &nmArray;
	delta = nmDelta;
	arrayLength = nmArray.size();
	selectedArray = &nmSelectedArray;
    }
    else if (selected == hr) {
	array = &hrArray;
	delta = hrDelta;
	arrayLength = hrArray.size();
	selectedArray = &hrSelectedArray;
    }
    else if (selected == kph) {
	array = &kphArray;
	delta = kphDelta;
	arrayLength = kphArray.size();
	selectedArray = &kphSelectedArray;
    }
    else if (selected == cad) {
	array = &cadArray;
	delta = cadDelta;
	arrayLength = cadArray.size();
	selectedArray = &cadSelectedArray;
    }

    if (!array)
        return;

    int count = int(ceil((arrayLength - 1) / binw));

    // allocate space for data, plus beginning and ending point
    QVector<double> parameterValue(count+2);
    QVector<double> totalTime(count+2);
    QVector<double> totalTimeSelected(count+2);
    int i;
    for (i = 1; i <= count; ++i) {
        int high = i * binw;
        int low = high - binw;
        if (low==0 && !withz)
            low++;
        parameterValue[i] = high * delta;
        totalTime[i]  = 1e-9;  // nonzero to accomodate log plot
        totalTimeSelected[i] = 1e-9;  // nonzero to accomodate log plot
        while (low < high) {
            if (selectedArray && (*selectedArray).size()>low)
                totalTimeSelected[i] += dt * (*selectedArray)[low];
            totalTime[i] += dt * (*array)[low++];
        }
    }
    totalTime[i] = 1e-9;       // nonzero to accomodate log plot
    parameterValue[i] = i * delta * binw;
    totalTime[0] = 1e-9;
    parameterValue[0] = 0;
    curve->setData(parameterValue.data(), totalTime.data(), count + 2);
    curveSelected->setData(parameterValue.data(), totalTimeSelected.data(), count + 2);
    setAxisScale(xBottom, 0.0, parameterValue[count + 1]);

    refreshZoneLabels();

    setYMax();
    replot();
}

void
PowerHist::setYMax()
{
    static const double tmin = 1.0/60;
    setAxisScale(yLeft, (lny ? tmin : 0.0), curve->maxYValue() * 1.1);
}

void
PowerHist::setData(RideItem *_rideItem)
{
    rideItem = _rideItem;

    RideFile *ride = rideItem->ride();

    if (ride) {
        setTitle(ride->startTime().toString(GC_DATETIME_FORMAT));

        static const int maxSize = 4096;

        // recording interval in minutes
        dt = ride->recIntSecs() / 60.0;

        wattsArray.resize(0);
        nmArray.resize(0);
        hrArray.resize(0);
        kphArray.resize(0);
        cadArray.resize(0);

        wattsSelectedArray.resize(0);
        nmSelectedArray.resize(0);
        hrSelectedArray.resize(0);
        kphSelectedArray.resize(0);
        cadSelectedArray.resize(0);

        // unit conversion factor for imperial units for selected parameters
        double torque_factor = (useMetricUnits ? 1.0 : 0.73756215);
        double speed_factor  = (useMetricUnits ? 1.0 : 0.62137119);

        foreach(const RideFilePoint *p1, ride->dataPoints()) {
            bool selected = isSelected(p1);

            int wattsIndex = int(floor(p1->watts / wattsDelta));
            if (wattsIndex >= 0 && wattsIndex < maxSize) {
                if (wattsIndex >= wattsArray.size())
                    wattsArray.resize(wattsIndex + 1);
                wattsArray[wattsIndex]++;

                if (selected) {
                    if (wattsIndex >= wattsSelectedArray.size())
                        wattsSelectedArray.resize(wattsIndex + 1);
                    wattsSelectedArray[wattsIndex]++;
                }
            }

            int nmIndex = int(floor(p1->nm * torque_factor / nmDelta));
            if (nmIndex >= 0 && nmIndex < maxSize) {
                if (nmIndex >= nmArray.size())
                    nmArray.resize(nmIndex + 1);
                nmArray[nmIndex]++;

                if (selected) {
                    if (nmIndex >= nmSelectedArray.size())
                        nmSelectedArray.resize(nmIndex + 1);
                    nmSelectedArray[nmIndex]++;
                }
            }

	    int hrIndex = int(floor(p1->hr / hrDelta));
	    if (hrIndex >= 0 && hrIndex < maxSize) {
            if (hrIndex >= hrArray.size())
               hrArray.resize(hrIndex + 1);
            hrArray[hrIndex]++;

            if (selected) {
                if (hrIndex >= hrSelectedArray.size())
                    hrSelectedArray.resize(hrIndex + 1);
                hrSelectedArray[hrIndex]++;
            }
	    }

	    int kphIndex = int(floor(p1->kph * speed_factor / kphDelta));
	    if (kphIndex >= 0 && kphIndex < maxSize) {
	        if (kphIndex >= kphArray.size())
	            kphArray.resize(kphIndex + 1);
	        kphArray[kphIndex]++;

            if (selected) {
                if (kphIndex >= kphSelectedArray.size())
                    kphSelectedArray.resize(kphIndex + 1);
                kphSelectedArray[kphIndex]++;
            }
	    }

	    int cadIndex = int(floor(p1->cad / cadDelta));
	    if (cadIndex >= 0 && cadIndex < maxSize) {
		    if (cadIndex >= cadArray.size())
		        cadArray.resize(cadIndex + 1);
		    cadArray[cadIndex]++;

            if (selected) {
                if (cadIndex >= cadSelectedArray.size())
                    cadSelectedArray.resize(cadIndex + 1);
                cadSelectedArray[cadIndex]++;
            }
	    }


	}

	recalc();
    }
    else {
	setTitle("no data");
	replot();
    }
    zoomer->setZoomBase();
}

void
PowerHist::setBinWidth(int value)
{
    binw = value;
    recalc();
}

double
PowerHist::getDelta()
{
    switch (selected) {
    case wattsShaded:
    case wattsUnshaded:
	return wattsDelta;
    case nm:
	return nmDelta;
    case hr:
	return hrDelta;
    case kph:
	return kphDelta;
    case cad:
	return cadDelta;
    }
    return 1;
}

int
PowerHist::getDigits()
{
    switch (selected) {
    case wattsShaded:
    case wattsUnshaded:
	return wattsDigits;
    case nm:
	return nmDigits;
    case hr:
	return hrDigits;
    case kph:
	return kphDigits;
    case cad:
	return cadDigits;
    }
    return 1;
}

int
PowerHist::setBinWidthRealUnits(double value)
{
    setBinWidth(round(value / getDelta()));
    return binw;
}

double
PowerHist::getBinWidthRealUnits()
{
    return binw * getDelta();
}

void
PowerHist::setWithZeros(bool value)
{
    withz = value;
    recalc();
}

void
PowerHist::setlnY(bool value)
{
    // note: setAxisScaleEngine deletes the old ScaleEngine, so specifying
    // "new" in the argument list is not a leak

    lny=value;
    if (lny)
    {
        setAxisScaleEngine(yLeft, new QwtLog10ScaleEngine);
	curve->setBaseline(1e-6);
    }
    else
    {
        setAxisScaleEngine(yLeft, new QwtLinearScaleEngine);
	curve->setBaseline(0);
    }
    setYMax();
    replot();
}

void
PowerHist::setParameterAxisTitle()
{
    setAxisTitle(
		 xBottom,
		 ((selected == wattsShaded) ||
		  (selected == wattsUnshaded)
		  ) ?
		 "watts" :
		 ((selected == hr) ?
		  "beats/minute" :
		  ((selected == cad) ?
		   "revolutions/min" :
		   useMetricUnits ?
		   ((selected == nm) ?
		    "newton-meters" :
		    ((selected == kph) ?
		     "km/hr" :
		     "undefined"
		     )
		    ) :
		   ((selected == nm) ?
		    "ft-lb" :
		    ((selected == kph) ?
		     "miles/hr" :
		     "undefined"
		     )
		    )
		   )
		  )
		 );
}

void
PowerHist::setSelection(Selection selection) {
    if (selected == selection)
	return;

    selected = selection;
    setParameterAxisTitle();
    recalc();
}


void
PowerHist::fixSelection() {

    Selection s = selected;
    RideFile *ride = rideItem->ride();

    if (ride)
        do
        {
	    if ((s == wattsShaded) || (s == wattsUnshaded))
            {
		if (ride->areDataPresent()->watts)
		    setSelection(s);
		else
		    s = nm;
            }

	    else if (s == nm)
            {
		if (ride->areDataPresent()->nm)
		    setSelection(s);
		else
		    s = hr;
            }

	    else if (s == hr)
            {
		if (ride->areDataPresent()->hr)
		    setSelection(s);
		else
		    s = kph;
            }

	    else if (s == kph)
            {
		if (ride->areDataPresent()->kph)
		    setSelection(s);
		else
		    s = cad;
            }

	    else if (s == cad)
            {
		if (ride->areDataPresent()->cad)
		    setSelection(s);
		else
		    s = wattsShaded;
            }
	} while (s != selected);
}


bool PowerHist::shadeZones() const
{
    return (
	    rideItem &&
	    rideItem->ride() &&
	    selected == wattsShaded
	    );
}

bool PowerHist::isSelected(const RideFilePoint *p) {
    if (mainWindow->allIntervalItems() != NULL) {
        for (int i=0; i<mainWindow->allIntervalItems()->childCount(); i++) {
            IntervalItem *current = dynamic_cast<IntervalItem*>(mainWindow->allIntervalItems()->child(i));
            if (current != NULL) {
                if (current->isSelected() && p->secs>=current->start && p->secs<=current->stop) {
                    return true;
                }
            }
        }
    }
    return false;
}