/* 
 * 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 "AllPlot.h"
#include "RideFile.h"
#include "Settings.h"

#include <assert.h>
#include <qwt_plot_curve.h>
#include <qwt_plot_grid.h>
#include <qwt_plot_marker.h>
#include <qwt_text.h>
#include <qwt_legend.h>
#include <qwt_data.h>

static const inline double
max(double a, double b) { if (a > b) return a; else return b; }

#define MILES_PER_KM 0.62137119

AllPlot::AllPlot() : 
    d_mrk(NULL), hrArray(NULL), wattsArray(NULL), 
    speedArray(NULL), cadArray(NULL), 
    timeArray(NULL), interArray(NULL), smooth(30), bydist(false),
    settings(GC_SETTINGS_CO, GC_SETTINGS_APP),
    unit(settings.value(GC_UNIT))
{
    insertLegend(new QwtLegend(), QwtPlot::BottomLegend);
    setCanvasBackground(Qt::white);

    setXTitle();
    
    wattsCurve = new QwtPlotCurve("Power");
    // wattsCurve->setRenderHint(QwtPlotItem::RenderAntialiased);
    wattsCurve->setPen(QPen(Qt::red));
    wattsCurve->attach(this);

    hrCurve = new QwtPlotCurve("Heart Rate");
    // hrCurve->setRenderHint(QwtPlotItem::RenderAntialiased);
    hrCurve->setPen(QPen(Qt::blue));
    hrCurve->attach(this);

    speedCurve = new QwtPlotCurve("Speed");
    // speedCurve->setRenderHint(QwtPlotItem::RenderAntialiased);
    speedCurve->setPen(QPen(Qt::green));
    speedCurve->setYAxis(yRight);
    speedCurve->attach(this);

    cadCurve = new QwtPlotCurve("Cadence");
    // cadCurve->setRenderHint(QwtPlotItem::RenderAntialiased);
    cadCurve->setPen(QPen(Qt::cyan));
    cadCurve->attach(this);

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

struct DataPoint {
    double time, hr, watts, speed, cad;
    int inter;
    DataPoint(double t, double h, double w, double s, double c, int i) : 
        time(t), hr(h), watts(w), speed(s), cad(c), inter(i) {}
};

void
AllPlot::recalc()
{
    if (!timeArray)
        return;
    int rideTimeSecs = (int) ceil(timeArray[arrayLength - 1]);
    if (rideTimeSecs > 7*24*60*60) {
        QwtArray<double> data;
        wattsCurve->setData(data, data);
        hrCurve->setData(data, data);
        speedCurve->setData(data, data);
        cadCurve->setData(data, data);
        return;
    }
    double totalWatts = 0.0;
    double totalHr = 0.0;
    double totalSpeed = 0.0;
    double totalCad = 0.0;
    double totalDist = 0.0;
    QList<DataPoint*> list;
    int i = 0;
    double *smoothWatts     = new double[rideTimeSecs + 1];
    double *smoothHr        = new double[rideTimeSecs + 1];
    double *smoothSpeed     = new double[rideTimeSecs + 1];
    double *smoothCad       = new double[rideTimeSecs + 1];
    double *smoothTime      = new double[rideTimeSecs + 1];
    double *smoothDistance  = new double[rideTimeSecs + 1];

    delete [] d_mrk;
    QList<double> interList; //Just store the time that it happened.
                             //Intervals are sequential.

    int lastInterval = 0; //Detect if we hit a new interval

    for (int secs = 0; ((secs < smooth) 
                        && (secs < rideTimeSecs)); ++secs) {
        smoothWatts[secs] = 0.0;
        smoothHr[secs]    = 0.0;
        smoothSpeed[secs] = 0.0;
        smoothCad[secs]   = 0.0;
        smoothTime[secs]  = secs / 60.0;
        smoothDistance[secs]  = 0.0;
    }
    for (int secs = smooth; secs <= rideTimeSecs; ++secs) {
        while ((i < arrayLength) && (timeArray[i] <= secs)) {
            DataPoint *dp = 
                new DataPoint(timeArray[i], hrArray[i], wattsArray[i], 
                              speedArray[i], cadArray[i], interArray[i]);
            totalWatts += wattsArray[i];
            totalHr    += hrArray[i];
            totalSpeed += speedArray[i];
            totalCad   += cadArray[i];
            totalDist   = distanceArray[i];
            list.append(dp);
            //Figure out when and if we have a new interval..
            if(lastInterval != interArray[i]) {
                lastInterval = interArray[i];
                interList.append(secs/60.0);
            }
            ++i;
        }
        while (!list.empty() && (list.front()->time < secs - smooth)) {
            DataPoint *dp = list.front();
            list.removeFirst();
            totalWatts -= dp->watts;
            totalHr    -= dp->hr;
            totalSpeed -= dp->speed;
            totalCad   -= dp->cad;
            delete dp;
        }
        // TODO: this is wrong.  We should do a weighted average over the
        // seconds represented by each point...
        if (list.empty()) {
            smoothWatts[secs] = 0.0;
            smoothHr[secs]    = 0.0;
            smoothSpeed[secs] = 0.0;
            smoothCad[secs]   = 0.0;
        }
        else {
            smoothWatts[secs]    = totalWatts / list.size();
            smoothHr[secs]       = totalHr / list.size();
            smoothSpeed[secs]    = totalSpeed / list.size();
            smoothCad[secs]      = totalCad / list.size();
        }
        smoothDistance[secs] = totalDist;
        smoothTime[secs]  = secs / 60.0;
    }
    if (!bydist) {
        wattsCurve->setData(smoothTime, smoothWatts, rideTimeSecs + 1);
        hrCurve->setData(smoothTime, smoothHr, rideTimeSecs + 1);
        speedCurve->setData(smoothTime, smoothSpeed, rideTimeSecs + 1);
        cadCurve->setData(smoothTime, smoothCad, rideTimeSecs + 1);
        setAxisScale(xBottom, 0.0, smoothTime[rideTimeSecs]);
    } else {
        wattsCurve->setData(smoothDistance, smoothWatts, rideTimeSecs + 1);
        hrCurve->setData(smoothDistance, smoothHr, rideTimeSecs + 1);
        speedCurve->setData(smoothDistance, smoothSpeed, rideTimeSecs + 1);
        cadCurve->setData(smoothDistance, smoothCad, rideTimeSecs + 1);
        setAxisScale(xBottom, 0.0, totalDist);
    }
    setYMax();
    
    QString label[interList.size()];
    QwtText text[interList.size()];
    d_mrk = new QwtPlotMarker[interList.size()];

    for(int x = 0; x < interList.size(); x++) {
        // marker
        d_mrk[x].setValue(0,0);
        d_mrk[x].setLineStyle(QwtPlotMarker::VLine);
        d_mrk[x].setLabelAlignment(Qt::AlignRight | Qt::AlignTop);
        d_mrk[x].setLinePen(QPen(Qt::black, 0, Qt::DashDotLine));
        d_mrk[x].attach(this);
        label[x].setNum(x+1);
        text[x] = QwtText(label[x]);
        text[x].setFont(QFont("Helvetica", 10, QFont::Bold));
        text[x].setColor(Qt::black);
        if (!bydist)
            d_mrk[x].setValue(interList.at(x), 0.0);
        else
            d_mrk[x].setValue(smoothDistance[int(ceil(60*interList.at(x)))], 0.0);
        d_mrk[x].setLabel(text[x]);
    }

    replot();
    delete [] smoothWatts;
    delete [] smoothHr;
    delete [] smoothSpeed;
    delete [] smoothCad;
    delete [] smoothTime;
    delete [] smoothDistance;
}

void
AllPlot::setYMax() 
{
    double ymax = 0;
    QString ylabel = "";
    if (wattsCurve->isVisible()) {
        ymax = max(ymax, wattsCurve->maxYValue());
        ylabel += QString((ylabel == "") ? "" : " / ") + "Watts";
    }
    if (hrCurve->isVisible()) {
        ymax = max(ymax, hrCurve->maxYValue());
        ylabel += QString((ylabel == "") ? "" : " / ") + "BPM";
    }
    if (cadCurve->isVisible()) {
        ymax = max(ymax, cadCurve->maxYValue());
        ylabel += QString((ylabel == "") ? "" : " / ") + "RPM";
    }
    setAxisScale(yLeft, 0.0, ymax * 1.1);
    setAxisTitle(yLeft, ylabel);

    enableAxis(yRight, speedCurve->isVisible());
    setAxisTitle(yRight, ((unit.toString() == "Metric") ? "KPH" : "MPH"));
}

void
AllPlot::setXTitle()
{
    if (bydist)
        setAxisTitle(xBottom, "Distance "+QString(unit.toString() == "Metric"?"(km)":"(miles)"));
    else
        setAxisTitle(xBottom, "Time (minutes)");
}

void
AllPlot::setData(RideFile *ride)
{
    delete [] wattsArray;
    delete [] hrArray;
    delete [] speedArray;
    delete [] cadArray;
    delete [] timeArray;
    delete [] interArray;
    delete [] distanceArray;

    setTitle(ride->startTime().toString(GC_DATETIME_FORMAT));
    wattsArray = new double[ride->dataPoints().size()];
    hrArray    = new double[ride->dataPoints().size()];
    speedArray    = new double[ride->dataPoints().size()];
    cadArray    = new double[ride->dataPoints().size()];
    timeArray  = new double[ride->dataPoints().size()];
    interArray = new int[ride->dataPoints().size()];
    distanceArray = new double[ride->dataPoints().size()];
    arrayLength = 0;
    QListIterator<RideFilePoint*> i(ride->dataPoints()); 
    while (i.hasNext()) {
        RideFilePoint *point = i.next();
        timeArray[arrayLength]  = point->secs;
        wattsArray[arrayLength] = max(0, point->watts);
        hrArray[arrayLength]    = max(0, point->hr);
        speedArray[arrayLength] = max(0, 
                    ((unit.toString() == "Metric")
                    ? point->kph
                    : point->kph * MILES_PER_KM));
        cadArray[arrayLength]   = max(0, point->cad);
        interArray[arrayLength] = point->interval;
        distanceArray[arrayLength] = max(0,
                  ((unit.toString() == "Metric")
                  ? point->km
                  : point->km * MILES_PER_KM));
        ++arrayLength;
    }
    recalc();
}

void
AllPlot::showPower(int state) 
{
    assert(state != Qt::PartiallyChecked);
    wattsCurve->setVisible(state == Qt::Checked);
    setYMax();
    replot();
}

void
AllPlot::showHr(int state) 
{
    assert(state != Qt::PartiallyChecked);
    hrCurve->setVisible(state == Qt::Checked);
    setYMax();
    replot();
}

void
AllPlot::showSpeed(int state) 
{
    assert(state != Qt::PartiallyChecked);
    speedCurve->setVisible(state == Qt::Checked);
    setYMax();
    replot();
}

void
AllPlot::showCad(int state) 
{
    assert(state != Qt::PartiallyChecked);
    cadCurve->setVisible(state == Qt::Checked);
    setYMax();
    replot();
}

void
AllPlot::showGrid(int state) 
{
    assert(state != Qt::PartiallyChecked);
    grid->setVisible(state == Qt::Checked);
    replot();
}

void
AllPlot::setSmoothing(int value)
{
    smooth = value;
    recalc();
}

void
AllPlot::setByDistance(int id)
{
    bydist = (id == 1);
    setXTitle();
    recalc();
}