/*

<codex>

*/

#import "LevelMeter.h"

int _cmp_levelThresholds(const void * a, const void * b)

{

    if (((LevelMeterColorThreshold *)a)->maxValue > ((LevelMeterColorThreshold *)b)->maxValue) return 1;

    if (((LevelMeterColorThreshold *)a)->maxValue < ((LevelMeterColorThreshold *)b)->maxValue) return -1;

    return 0;

}

@implementation LevelMeter

@synthesize vertical = _vertical;

@synthesize bgColor = _bgColor;

@synthesize borderColor = _borderColor;

@synthesize variableLightIntensity = _variableLightIntensity;

- (void)_performInit

{

    _level = 0.;

    _numLights = 0;

    _numColorThresholds = 3;

    _variableLightIntensity = YES;

    _bgColor = [[UIColor alloc] initWithRed:0. green:0. blue:0. alpha:0.6];

    _borderColor = [[UIColor alloc] initWithRed:0. green:0. blue:0. alpha:1.];

    _colorThresholds = malloc(3 * sizeof(LevelMeterColorThreshold));

    _colorThresholds[0].maxValue = 0.25;

    _colorThresholds[0].color = [[UIColor alloc] initWithRed:0. green:1. blue:0. alpha:1.];

    _colorThresholds[1].maxValue = 0.8;

    _colorThresholds[1].color = [[UIColor alloc] initWithRed:1. green:1. blue:0. alpha:1.];

    _colorThresholds[2].maxValue = 1.;

    _colorThresholds[2].color = [[UIColor alloc] initWithRed:1. green:0. blue:0. alpha:1.];

    _vertical = ([self frame].size.width < [self frame].size.height) ? YES : NO;

}

- (id)initWithFrame:(CGRect)frame

{

    if (self = [super initWithFrame:frame]) {

        [self _performInit];

    }

    return self;

}

- (id)initWithCoder:(NSCoder *)coder

{

    if (self = [super initWithCoder:coder]) {

        [self _performInit];

    }

    return self;

}

- (void)drawRect:(CGRect)rect

{

    CGColorSpaceRef cs = NULL;

    CGContextRef cxt = NULL;

    CGRect bds;

    cxt = UIGraphicsGetCurrentContext();

    cs = CGColorSpaceCreateDeviceRGB();

    if (_vertical)

    {

        CGContextTranslateCTM(cxt, 0., [self bounds].size.height);

        CGContextScaleCTM(cxt, 1., -1.);

        bds = [self bounds];

    } else {

        CGContextTranslateCTM(cxt, 0., [self bounds].size.height);

        CGContextRotateCTM(cxt, -M_PI_2);

        bds = CGRectMake(0., 0., [self bounds].size.height, [self bounds].size.width);

    }

    CGContextSetFillColorSpace(cxt, cs);

    CGContextSetStrokeColorSpace(cxt, cs);

    if (_numLights == 0)

    {

        int i;

        CGFloat currentTop = 0.;

        if (_bgColor)

        {

            [_bgColor set];

            CGContextFillRect(cxt, bds);

        }

        for (i=0; i<_numColorThresholds; i++)

        {

            LevelMeterColorThreshold thisThresh = _colorThresholds[i];

            CGFloat val = MIN(thisThresh.maxValue, _level);

            CGRect rect = CGRectMake(

                                     0, 

                                     (bds.size.height) * currentTop, 

                                     bds.size.width, 

                                     (bds.size.height) * (val - currentTop)

                                     );

            [thisThresh.color set];

            CGContextFillRect(cxt, rect);

            if (_level < thisThresh.maxValue) break;

            currentTop = val;

        }

        if (_borderColor)

        {

            [_borderColor set];

            CGContextStrokeRect(cxt, CGRectInset(bds, .5, .5));

        }

    } else {

        int light_i;

        CGFloat lightMinVal = 0.;

        CGFloat insetAmount, lightVSpace;

        lightVSpace = bds.size.height / (CGFloat)_numLights;

        if (lightVSpace < 4.) insetAmount = 0.;

        else if (lightVSpace < 8.) insetAmount = 0.5;

        else insetAmount = 1.;

        int peakLight = -1;

        if (_peakLevel > 0.)

        {

            peakLight = _peakLevel * _numLights;

            if (peakLight >= _numLights) peakLight = _numLights - 1;

        }

        for (light_i=0; light_i<_numLights; light_i++)

        {

            CGFloat lightMaxVal = (CGFloat)(light_i + 1) / (CGFloat)_numLights;

            CGFloat lightIntensity;

            CGRect lightRect;

            UIColor *lightColor;

            if (light_i == peakLight)

            {

                lightIntensity = 1.;

            } else {

                lightIntensity = (_level - lightMinVal) / (lightMaxVal - lightMinVal);

                lightIntensity = LEVELMETER_CLAMP(0., lightIntensity, 1.);

                if ((!_variableLightIntensity) && (lightIntensity > 0.)) lightIntensity = 1.;

            }

            lightColor = _colorThresholds[0].color;

            int color_i;

            for (color_i=0; color_i<(_numColorThresholds-1); color_i++)

            {

                LevelMeterColorThreshold thisThresh = _colorThresholds[color_i];

                LevelMeterColorThreshold nextThresh = _colorThresholds[color_i + 1];

                if (thisThresh.maxValue <= lightMaxVal) lightColor = nextThresh.color;

            }

            lightRect = CGRectMake(

                                   0., 

                                   bds.size.height * ((CGFloat)(light_i) / (CGFloat)_numLights), 

                                   bds.size.width,

                                   bds.size.height * (1. / (CGFloat)_numLights)

                                   );

            lightRect = CGRectInset(lightRect, insetAmount, insetAmount);

            if (_bgColor)

            {

                [_bgColor set];

                CGContextFillRect(cxt, lightRect);

            }

            if (lightIntensity == 1.)

            {

                [lightColor set];

                CGContextFillRect(cxt, lightRect);

            } else if (lightIntensity > 0.) {

                CGColorRef clr = CGColorCreateCopyWithAlpha([lightColor CGColor], lightIntensity);

                CGContextSetFillColorWithColor(cxt, clr);

                CGContextFillRect(cxt, lightRect);

                CGColorRelease(clr);

            }

            if (_borderColor)

            {

                [_borderColor set];

                CGContextStrokeRect(cxt, CGRectInset(lightRect, 0.5, 0.5));

            }

            lightMinVal = lightMaxVal;

        }

    }

    CGColorSpaceRelease(cs);

}

- (void)dealloc {

    int i;

    for (i=0; i<_numColorThresholds; i++) [_colorThresholds[i].color release];

    free(_colorThresholds);

    [_bgColor release];

    [_borderColor release];

    [super dealloc];

}

- (CGFloat)level { return _level; }

- (void)setLevel:(CGFloat)v { _level = v; }

- (CGFloat)peakLevel { return _peakLevel; }

- (void)setPeakLevel:(CGFloat)v { _peakLevel = v; }

- (NSUInteger)numLights { return _numLights; }

- (void)setNumLights:(NSUInteger)v { _numLights = v; }

- (LevelMeterColorThreshold *)colorThresholds:(NSUInteger *)count

{

    *count = _numColorThresholds;

    return _colorThresholds;

}

- (void)setColorThresholds:(LevelMeterColorThreshold *)thresholds count:(NSUInteger)count

{

    int i;

    for (i=0; i<_numColorThresholds; i++) [_colorThresholds[i].color release];

    _colorThresholds = realloc(_colorThresholds, sizeof(LevelMeterColorThreshold) * count);

    for (i=0; i<count; i++)

    {

        _colorThresholds[i].maxValue = thresholds[i].maxValue;

        _colorThresholds[i].color = [thresholds[i].color copy];

    }

    qsort(_colorThresholds, count, sizeof(LevelMeterColorThreshold), _cmp_levelThresholds);

    _numColorThresholds = count;

}

@end