//
//  GKPageControl.m
//  GKCycleScrollViewDemo
//
//  Created by QuintGao on 2019/9/21.
//  Copyright © 2019 QuintGao. All rights reserved.
//

#import "GKPageControl.h"

@interface GKPageDotView : UIView

@property (nonatomic, assign) NSInteger numberOfPages;
@property (nonatomic, assign) NSInteger currentPage;
@property (nonatomic, strong) UIColor *pageIndicatorColor;
@property (nonatomic, strong) UIColor *currentPageIndicatorColor;

@property (nonatomic, assign) CGFloat dotWidth;
@property (nonatomic, assign) CGFloat dotHeight;
@property (nonatomic, assign) CGFloat dotMargin;

@end

@implementation GKPageDotView

- (void)setCurrentPage:(NSInteger)currentPage {
    if (_currentPage == currentPage) return;
    
    _currentPage = MIN(currentPage, self.numberOfPages - 1);
    
    for (NSInteger i = 0; i < self.numberOfPages; i++) {
        UIView *dotView = self.subviews[i];
        if (currentPage == i) {
            dotView.backgroundColor = self.currentPageIndicatorColor;
        }else {
            dotView.backgroundColor = self.pageIndicatorColor;
        }
    }
    [self layoutSubviews];
}

- (void)setNumberOfPages:(NSInteger)numberOfPages {
    if (_numberOfPages == numberOfPages) return;
    _numberOfPages = MAX(0, numberOfPages);
    [self.subviews makeObjectsPerformSelector:@selector(removeFromSuperview)];
    
    for (NSInteger i = 0; i < numberOfPages; i++) {
        UIView *dotView = [UIView new];
        if (self.currentPage == i) {
            dotView.backgroundColor = self.currentPageIndicatorColor;
        }else {
            dotView.backgroundColor = self.pageIndicatorColor;
        }
        dotView.layer.cornerRadius = self.dotHeight * 0.5f;
        dotView.layer.masksToBounds = YES;
        [self addSubview:dotView];
    }
    [self layoutSubviews];
}

- (void)layoutSubviews {
    [super layoutSubviews];
    
    CGFloat selectW = 2 * self.dotWidth + self.dotMargin;
    
    CGFloat viewX = (self.frame.size.width - self.dotWidth * (self.numberOfPages + 1) - self.dotMargin * self.numberOfPages) / 2;
    CGFloat viewY = (self.frame.size.height - self.dotHeight) / 2;
    
    for (NSInteger i = 0; i < self.numberOfPages; i++) {
        UIView *dotView = self.subviews[i];
        
        if (self.currentPage == i) {
            dotView.frame = CGRectMake(viewX, viewY, selectW, self.dotHeight);
            viewX += selectW + self.dotMargin;
        }else {
            dotView.frame = CGRectMake(viewX, viewY, self.dotWidth, self.dotHeight);
            viewX += self.dotWidth + self.dotMargin;
        }
    }
}

@end

@interface GKPageControl()

@property (nonatomic, strong) GKPageDotView *pageDotView;

@end

@implementation GKPageControl

- (instancetype)initWithFrame:(CGRect)frame {
    if (self = [super initWithFrame:frame]) {
        self.pageIndicatorTintColor = [UIColor grayColor];
        self.currentPageIndicatorTintColor = [UIColor whiteColor];
        
        self.dotWidth  = 8;
        self.dotHeight = 8;
        self.dotMargin = 8;
    }
    return self;
}

- (void)setStyle:(GKPageControlStyle)style {
    _style = style;
    
    if (style == GKPageControlStyleRectangle) {
        self.dotWidth = 20;
        self.dotHeight = 4;
    }else if (style == GKPageControlStyleSizeDot) {
        self.pageDotView.dotWidth = self.dotWidth;
        self.pageDotView.dotHeight = self.dotHeight;;
        self.pageDotView.dotMargin = self.dotMargin;
        [self.pageDotView layoutSubviews];
    }
}

- (void)setDotWidth:(CGFloat)dotWidth {
    _dotWidth = dotWidth;
    
    if (self.style == GKPageControlStyleSizeDot) {
        self.pageDotView.dotWidth = dotWidth;
        [self.pageDotView layoutSubviews];
    }
}

- (void)setDotHeight:(CGFloat)dotHeight {
    _dotHeight = dotHeight;
    
    if (self.style == GKPageControlStyleSizeDot) {
        self.pageDotView.dotHeight = dotHeight;
        [self.pageDotView layoutSubviews];
    }
}

- (void)setDotMargin:(CGFloat)dotMargin {
    _dotMargin = dotMargin;
    
    if (self.style == GKPageControlStyleSizeDot) {
        self.pageDotView.dotMargin = dotMargin;
        [self.pageDotView layoutSubviews];
    }
}

- (void)setNumberOfPages:(NSInteger)numberOfPages {
    [super setNumberOfPages:numberOfPages];
    
    if (self.style == GKPageControlStyleSystem) return;
    
    [self.subviews makeObjectsPerformSelector:@selector(removeFromSuperview)];
    
    if (self.style == GKPageControlStyleSizeDot) {
        [self addSubview:self.pageDotView];
        self.pageDotView.numberOfPages = numberOfPages;
        return;
    }
    
    for (NSInteger i = 0; i < numberOfPages; i++) {
        UIView *dotView = [UIView new];
        dotView.tag = [dotView hash] + i;
        
        if (self.hidesForSinglePage && numberOfPages == 1) {
            dotView.hidden = YES;
        }
        
        [self addSubview:dotView];
    }
}

- (void)setCurrentPage:(NSInteger)currentPage {
    [super setCurrentPage:currentPage];
    
    if (self.style == GKPageControlStyleSystem) return;
    
    if (self.style == GKPageControlStyleSizeDot) {
        self.pageDotView.currentPage = currentPage;
        return;
    }
    
    [super setCurrentPage:currentPage];
    
    [self.subviews enumerateObjectsUsingBlock:^(__kindof UIView * _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
        obj.backgroundColor = currentPage == idx ? self.currentPageIndicatorTintColor : self.pageIndicatorTintColor;
    }];
}

- (void)setPageIndicatorTintColor:(UIColor *)pageIndicatorTintColor {
    [super setPageIndicatorTintColor:pageIndicatorTintColor];
    
    if (self.style == GKPageControlStyleSizeDot) {
        self.pageDotView.pageIndicatorColor = pageIndicatorTintColor;
    }
}

- (void)setCurrentPageIndicatorTintColor:(UIColor *)currentPageIndicatorTintColor {
    [super setCurrentPageIndicatorTintColor:currentPageIndicatorTintColor];
    
    if (self.style == GKPageControlStyleSizeDot) {
        self.pageDotView.currentPageIndicatorColor = currentPageIndicatorTintColor;
    }
}

- (void)layoutSubviews {
    [super layoutSubviews];
    
    if (self.style == GKPageControlStyleSystem) return;
    
    [self.subviews enumerateObjectsUsingBlock:^(__kindof UIView * _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
        if (obj.tag == [obj hash] + idx) {
            
            switch (self.style) {
                case GKPageControlStyleCycle: {
                    CGFloat objW = self.dotWidth;
                    CGFloat objH = self.dotHeight;
                    
                    CGFloat originX = (self.frame.size.width - objW * self.numberOfPages - self.dotMargin * (self.numberOfPages - 1)) / 2;
                    CGFloat objX = originX + (self.dotMargin + objW) * idx;
                    CGFloat objy = (self.frame.size.height - objH) / 2;
                    
                    obj.frame = CGRectMake(objX, objy, objW, objH);
                    obj.layer.cornerRadius = objW / 2;
                    obj.layer.masksToBounds = YES;
                }
                    break;
                case GKPageControlStyleRectangle: {
                    CGFloat objW = self.dotWidth;
                    CGFloat objH = self.dotHeight;
                    
                    CGFloat originX = (self.frame.size.width - objW * self.numberOfPages - self.dotMargin * (self.numberOfPages - 1)) / 2;
                    CGFloat objX = originX + (self.dotMargin + objW) * idx;
                    CGFloat objy = (self.frame.size.height - objH) / 2;
                    obj.layer.cornerRadius = 2.5;
                    obj.layer.masksToBounds = YES;
                    obj.frame = CGRectMake(objX, objy, objW, objH);
                }
                    break;
                case GKPageControlStyleSquare: {
                    CGFloat objW = self.dotWidth;
                    CGFloat objH = self.dotHeight;
                    
                    CGFloat originX = (self.frame.size.width - objW * self.numberOfPages - self.dotMargin * (self.numberOfPages - 1)) / 2;
                    CGFloat objX = originX + (self.dotMargin + objW) * idx;
                    CGFloat objy = (self.frame.size.height - objH) / 2;
                    
                    obj.frame = CGRectMake(objX, objy, objW, objH);
                }
                    break;
                case GKPageControlStyleSizeDot:
                    obj.frame = self.bounds;
                    break;
                default:
                    break;
            }
        }else {
            [obj removeFromSuperview];
        }
    }];
}

#pragma mark - 懒加载
- (GKPageDotView *)pageDotView {
    if (!_pageDotView) {
        _pageDotView = [[GKPageDotView alloc] initWithFrame:self.bounds];
        _pageDotView.pageIndicatorColor = self.pageIndicatorTintColor;
        _pageDotView.currentPageIndicatorColor = self.currentPageIndicatorTintColor;
        _pageDotView.tag = [_pageDotView hash];
    }
    return _pageDotView;
}

@end