///
//  RMPath.m
//
// Copyright (c) 2008-2009, Route-Me Contributors
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// * Redistributions of source code must retain the above copyright notice, this
//   list of conditions and the following disclaimer.
// * 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 BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 THE COPYRIGHT OWNER 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.

#import "RMPath.h"
#import "RMPixel.h"
#import "RMProjection.h"
#import "RMMapView.h"
#import "RMAnnotation.h"

@implementation RMPath

@synthesize scaleLineWidth;
@synthesize lineDashPhase;
@synthesize scaleLineDash;
@synthesize shadowBlur;
@synthesize shadowOffset;
@synthesize enableShadow;
@synthesize pathBoundingBox;

#define kDefaultLineWidth 2.0

- (id)initWithView:(RMMapView *)aMapView
{
    if (!(self = [super init]))
        return nil;

    mapView = aMapView;

    path = CGPathCreateMutable();
    pathBoundingBox = CGRectZero;
    ignorePathUpdates = NO;
    previousBounds = CGRectZero;

    lineWidth = kDefaultLineWidth;
    drawingMode = kCGPathFillStroke;
    lineCap = kCGLineCapButt;
    lineJoin = kCGLineJoinMiter;
    lineColor = [UIColor blackColor];
    fillColor = [UIColor redColor];

    _lineDashCount = 0;
    _lineDashLengths = NULL;
    _scaledLineDashLengths = NULL;
    lineDashPhase = 0.0;

    self.shadowBlur = 0.0;
    self.shadowOffset = CGSizeMake(0, 0);
    self.enableShadow = NO;

    self.masksToBounds = YES;

    scaleLineWidth = NO;
    scaleLineDash = NO;
    isFirstPoint = YES;

    if ([self respondsToSelector:@selector(setContentsScale:)])
        [(id)self setValue:[[UIScreen mainScreen] valueForKey:@"scale"] forKey:@"contentsScale"];

    return self;
}

- (void)dealloc
{
    mapView = nil;
    CGPathRelease(path); path = NULL;
    [self setLineDashLengths:nil];
    [lineColor release]; lineColor = nil;
    [fillColor release]; fillColor = nil;
    [super dealloc];
}

//- (id <CAAction>)actionForKey:(NSString *)key
//{
//    return nil;
//}

#pragma mark -

- (void)recalculateGeometry
{
    if (ignorePathUpdates)
        return;

    CGPoint myPosition = self.annotation.position;

    float scale = [mapView metersPerPixel];
    float scaledLineWidth;
    CGRect pixelBounds, screenBounds;
    float offset;
    const float outset = 100.0f; // provides a buffer off screen edges for when path is scaled or moved

    // The bounds are actually in mercators...
    /// \bug if "bounds are actually in mercators", shouldn't be using a CGRect
    scaledLineWidth = lineWidth;

    if (!scaleLineWidth)
    {
        renderedScale = [mapView metersPerPixel];
        scaledLineWidth *= renderedScale;
    }

    CGRect boundsInMercators = CGPathGetBoundingBox(path);
    boundsInMercators = CGRectInset(boundsInMercators, -scaledLineWidth, -scaledLineWidth);
    pixelBounds = CGRectInset(boundsInMercators, -scaledLineWidth, -scaledLineWidth);
    pixelBounds = RMScaleCGRectAboutPoint(pixelBounds, 1.0f / scale, CGPointZero);

    // Clip bound rect to screen bounds.
    // If bounds are not clipped, they won't display when you zoom in too much.
    screenBounds = [mapView frame];

    // Clip top
    offset = myPosition.y + pixelBounds.origin.y - screenBounds.origin.y + outset;
    if (offset < 0.0f)
    {
        pixelBounds.origin.y -= offset;
        pixelBounds.size.height += offset;
    }

    // Clip left
    offset = myPosition.x + pixelBounds.origin.x - screenBounds.origin.x + outset;
    if (offset < 0.0f)
    {
        pixelBounds.origin.x -= offset;
        pixelBounds.size.width += offset;
    }

    // Clip bottom
    offset = myPosition.y + pixelBounds.origin.y + pixelBounds.size.height - screenBounds.origin.y - screenBounds.size.height - outset;
    if (offset > 0.0f)
    {
        pixelBounds.size.height -= offset;
    }

    // Clip right
    offset = myPosition.x + pixelBounds.origin.x + pixelBounds.size.width - screenBounds.origin.x - screenBounds.size.width - outset;
    if (offset > 0.0f)
    {
        pixelBounds.size.width -= offset;
    }

    [super setPosition:myPosition];
    self.bounds = pixelBounds;
    previousBounds = pixelBounds;

//    RMLog(@"x:%f y:%f screen bounds: %f %f %f %f", myPosition.x, myPosition.y,  screenBounds.origin.x, screenBounds.origin.y, screenBounds.size.width, screenBounds.size.height);
//    RMLog(@"new bounds: %f %f %f %f", self.bounds.origin.x, self.bounds.origin.y, self.bounds.size.width, self.bounds.size.height);

    pathBoundingBox = CGRectMake(myPosition.x + self.bounds.origin.x, myPosition.y + self.bounds.origin.y, self.bounds.size.width, self.bounds.size.height);
    self.anchorPoint = CGPointMake(-pixelBounds.origin.x / pixelBounds.size.width, -pixelBounds.origin.y / pixelBounds.size.height);

    [self setNeedsDisplay];
}

- (void)drawInContext:(CGContextRef)theContext
{
    renderedScale = [mapView metersPerPixel];
    CGFloat *dashLengths = _lineDashLengths;

    float scale = 1.0f / [mapView metersPerPixel];

    float scaledLineWidth = lineWidth;
    if (!scaleLineWidth)
        scaledLineWidth *= renderedScale;

    // NSLog(@"line width = %f, content scale = %f", scaledLineWidth, renderedScale);

    if (!scaleLineDash && _lineDashLengths)
    {
        dashLengths = _scaledLineDashLengths;

        for (size_t dashIndex=0; dashIndex<_lineDashCount; dashIndex++)
            dashLengths[dashIndex] = _lineDashLengths[dashIndex] * renderedScale;
    }

    CGContextScaleCTM(theContext, scale, scale);

    CGContextBeginPath(theContext);
    CGContextAddPath(theContext, path);

    CGContextSetLineWidth(theContext, scaledLineWidth);
    CGContextSetLineCap(theContext, lineCap);
    CGContextSetLineJoin(theContext, lineJoin);
    CGContextSetStrokeColorWithColor(theContext, [lineColor CGColor]);
    CGContextSetFillColorWithColor(theContext, [fillColor CGColor]);

    if (_lineDashLengths)
        CGContextSetLineDash(theContext, lineDashPhase, dashLengths, _lineDashCount);

    if (self.enableShadow)
        CGContextSetShadow(theContext, self.shadowOffset, self.shadowBlur);

    // according to Apple's documentation, DrawPath closes the path if it's a filled style, so a call to ClosePath isn't necessary
    CGContextDrawPath(theContext, drawingMode);
}

#pragma mark -

- (void)addPointToProjectedPoint:(RMProjectedPoint)point withDrawing:(BOOL)isDrawing
{
    //	RMLog(@"addLineToXY %f %f", point.x, point.y);

    if (isFirstPoint)
    {
        isFirstPoint = FALSE;
        projectedLocation = point;

        self.position = [mapView projectedPointToPixel:projectedLocation];
        // RMLog(@"screen position set to %f %f", self.position.x, self.position.y);
        CGPathMoveToPoint(path, NULL, 0.0f, 0.0f);
    }
    else
    {
        point.x = point.x - projectedLocation.x;
        point.y = point.y - projectedLocation.y;

        if (isDrawing)
            CGPathAddLineToPoint(path, NULL, point.x, -point.y);
        else
            CGPathMoveToPoint(path, NULL, point.x, -point.y);

        [self recalculateGeometry];
    }

    [self setNeedsDisplay];
}

- (void)moveToProjectedPoint:(RMProjectedPoint)projectedPoint
{
    [self addPointToProjectedPoint:projectedPoint withDrawing:NO];
}

- (void)moveToScreenPoint:(CGPoint)point
{
    RMProjectedPoint mercator = [mapView pixelToProjectedPoint:point];
    [self moveToProjectedPoint:mercator];
}

- (void)moveToCoordinate:(CLLocationCoordinate2D)coordinate
{
    RMProjectedPoint mercator = [[mapView projection] coordinateToProjectedPoint:coordinate];
    [self moveToProjectedPoint:mercator];
}

- (void)addLineToProjectedPoint:(RMProjectedPoint)projectedPoint
{
    [self addPointToProjectedPoint:projectedPoint withDrawing:YES];
}

- (void)addLineToScreenPoint:(CGPoint)point
{
    RMProjectedPoint mercator = [mapView pixelToProjectedPoint:point];
    [self addLineToProjectedPoint:mercator];
}

- (void)addLineToCoordinate:(CLLocationCoordinate2D)coordinate
{
    RMProjectedPoint mercator = [[mapView projection] coordinateToProjectedPoint:coordinate];
    [self addLineToProjectedPoint:mercator];
}

- (void)performBatchOperations:(void (^)(RMPath *aPath))block
{
    ignorePathUpdates = YES;
    block(self);
    ignorePathUpdates = NO;

    [self recalculateGeometry];
}

#pragma mark - Accessors

- (void)closePath
{
    CGPathCloseSubpath(path);
}

- (float)lineWidth
{
    return lineWidth;
}

- (void)setLineWidth:(float)newLineWidth
{
    lineWidth = newLineWidth;
    [self recalculateGeometry];
}

- (CGPathDrawingMode)drawingMode
{
    return drawingMode;
}

- (void)setDrawingMode:(CGPathDrawingMode)newDrawingMode
{
    drawingMode = newDrawingMode;
    [self setNeedsDisplay];
}

- (CGLineCap)lineCap
{
    return lineCap;
}

- (void)setLineCap:(CGLineCap)newLineCap
{
    lineCap = newLineCap;
    [self setNeedsDisplay];
}

- (CGLineJoin)lineJoin
{
    return lineJoin;
}

- (void)setLineJoin:(CGLineJoin)newLineJoin
{
    lineJoin = newLineJoin;
    [self setNeedsDisplay];
}

- (UIColor *)lineColor
{
    return lineColor; 
}

- (void)setLineColor:(UIColor *)aLineColor
{
    if (lineColor != aLineColor)
    {
        [lineColor release];
        lineColor = [aLineColor retain];
        [self setNeedsDisplay];
    }
}

- (UIColor *)fillColor
{
    return fillColor; 
}

- (void)setFillColor:(UIColor *)aFillColor
{
    if (fillColor != aFillColor)
    {
        [fillColor release];
        fillColor = [aFillColor retain];
        [self setNeedsDisplay];
    }
}

- (NSArray *)lineDashLengths
{
    NSMutableArray *lengths = [NSMutableArray arrayWithCapacity:_lineDashCount];

    for (size_t dashIndex=0; dashIndex<_lineDashCount; dashIndex++)
        [lengths addObject:(id)[NSNumber numberWithFloat:_lineDashLengths[dashIndex]]];

    return lengths;
}

- (void)setLineDashLengths:(NSArray *)lengths
{
    if (_lineDashLengths)
    {
        free(_lineDashLengths);
        _lineDashLengths = NULL;
    }

    if (_scaledLineDashLengths)
    {
        free(_scaledLineDashLengths);
        _scaledLineDashLengths = NULL;
    }

    _lineDashCount = [lengths count];

    if (!_lineDashCount)
        return;

    _lineDashLengths = calloc(_lineDashCount, sizeof(CGFloat));
    if (!scaleLineDash)
        _scaledLineDashLengths = calloc(_lineDashCount, sizeof(CGFloat));

    NSEnumerator *lengthEnumerator = [lengths objectEnumerator];
    id lenObj;
    size_t dashIndex = 0;

    while ((lenObj = [lengthEnumerator nextObject]))
    {
        if ([lenObj isKindOfClass:[NSNumber class]])
        {
            _lineDashLengths[dashIndex] = [lenObj floatValue];
        }
        else
        {
            _lineDashLengths[dashIndex] = 0.0;
            dashIndex++;
        }
    }
}

- (void)setPosition:(CGPoint)newPosition
{
    if (CGPointEqualToPoint(newPosition, super.position) && CGRectEqualToRect(self.bounds, previousBounds)) return;

    [self recalculateGeometry];
}

@end