/*
 * Copyright 2011 Ytai Ben-Tsvi. All rights reserved.
 *
 *
 * Redistribution and use in source and binary forms, with or without modification, are
 * permitted provided that the following conditions are met:
 *
 *    1. Redistributions of source code must retain the above copyright notice, this list of
 *       conditions and the following disclaimer.
 *
 *    2. Redistributions in binary form must reproduce the above copyright notice, this list
 *       of conditions and the following disclaimer in the documentation and/or other materials
 *       provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL ARSHAN POURSOHI OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * The views and conclusions contained in the software and documentation are those of the
 * authors and should not be interpreted as representing official policies, either expressed
 * or implied.
 */
package ioio.lib.impl;

import ioio.lib.api.PwmOutput;
import ioio.lib.api.exception.ConnectionLostException;
import ioio.lib.impl.ResourceManager.Resource;

import java.io.IOException;

class PwmImpl extends AbstractPin implements PwmOutput {
    private final Resource pwm_;
    private final float baseUs_;
    private final int period_;

    public PwmImpl(IOIOImpl ioio, Resource pin, Resource pwm, int period,
                   float baseUs) throws ConnectionLostException {
        super(ioio, pin);
        pwm_ = pwm;
        baseUs_ = baseUs;
        period_ = period;
    }

    @Override
    public synchronized void close() {
        checkClose();
        try {
            ioio_.protocol_.setPwmPeriod(pwm_.id, 0, IOIOProtocol.PwmScale.SCALE_1X);
            ioio_.resourceManager_.free(pwm_);
        } catch (IOException e) {
        }
        super.close();
    }

    @Override
    public void setDutyCycle(float dutyCycle) throws ConnectionLostException, RuntimeException {
        if (dutyCycle > 1 || dutyCycle < 0) {
            throw new RuntimeException("dutyCycle must be between 0 and 1. A dutyCycle of " + dutyCycle + " was given.");
        }
        setPulseWidthInClocks(period_ * dutyCycle);
    }

    @Override
    public void setPulseWidth(int pulseWidthUs) throws ConnectionLostException, RuntimeException {
        setPulseWidth((float) pulseWidthUs);
    }

    @Override
    public void setPulseWidth(float pulseWidthUs)
            throws ConnectionLostException, RuntimeException {
        if (pulseWidthUs < 0) {
            throw new RuntimeException("pulseWidthUs must be larger than 0. A pulseWidthUs of " + pulseWidthUs + " was given.");
        }
        float p = pulseWidthUs / baseUs_;
        setPulseWidthInClocks(p);
    }

    synchronized private void setPulseWidthInClocks(float p)
            throws ConnectionLostException {
        checkState();
        if (p > period_) {
            p = period_;
        }
        int pw;
        int fraction;
        p -= 1; // period parameter is one less than the actual period length
        // yes, there is 0 and then 2 (no 1) - this is not a bug, that
        // is how the hardware PWM module works.
        if (p < 1) {
            pw = 0;
            fraction = 0;
        } else {
            pw = (int) p;
            fraction = (int) (p * 4) & 0x03;
        }
        try {
            ioio_.protocol_.setPwmDutyCycle(pwm_.id, pw, fraction);
        } catch (IOException e) {
            throw new ConnectionLostException(e);
        }
    }
}
