#import "CustomKeyboard.h"
#import <React/RCTUIManager.h>
#import "RCTBaseTextInputView.h"

@implementation CustomKeyboard

@synthesize bridge = _bridge;

- (dispatch_queue_t)methodQueue
{
    return dispatch_get_main_queue();
}

- (BOOL)isEmoji:(NSString*) str {
    const unichar high = [str characterAtIndex: 0];
    
    // Surrogate pair (U+1D000-1F77F)
    if (0xd800 <= high && high <= 0xdbff) {
        const unichar low = [str characterAtIndex: 1];
        const int codepoint = ((high - 0xd800) * 0x400) + (low - 0xdc00) + 0x10000;
        
        return (0x1d000 <= codepoint && codepoint <= 0x1f77f);
        
    // Not surrogate pair (U+2100-27BF)
    } else {
        return (0x2100 <= high && high <= 0x27bf);
    }
}

RCT_EXPORT_MODULE(CustomKeyboard)

RCT_EXPORT_METHOD(install:(nonnull NSNumber *)reactTag withType:(nonnull NSString *)keyboardType)
{
    UIView* inputView = [[RCTRootView alloc] initWithBridge:_bridge moduleName:@"CustomKeyboard" initialProperties:
                         @{
                           @"tag": reactTag,
                           @"type": keyboardType
                           }
                         ];
    
    inputView.autoresizingMask = UIViewAutoresizingNone;
    inputView.frame = CGRectMake(0, 0, [UIScreen mainScreen].bounds.size.width, 252);
    
    UITextField *view = (UITextField *)(((RCTBaseTextInputView*)[_bridge.uiManager viewForReactTag:reactTag]).backedTextInputView);
    
    view.inputView = inputView;
    [view reloadInputViews];
}

RCT_EXPORT_METHOD(uninstall:(nonnull NSNumber *)reactTag)
{
    UITextField *view = (UITextField *)(((RCTBaseTextInputView*)[_bridge.uiManager viewForReactTag:reactTag]).backedTextInputView);
    
    view.inputView = nil;
    [view reloadInputViews];
}

RCT_EXPORT_METHOD(insertText:(nonnull NSNumber *)reactTag withText:(NSString*)text) {
    UITextField *view = (UITextField *)(((RCTBaseTextInputView*)[_bridge.uiManager viewForReactTag:reactTag]).backedTextInputView);
    
    [view replaceRange:view.selectedTextRange withText:text];
}

RCT_EXPORT_METHOD(backSpace:(nonnull NSNumber *)reactTag) {
    UITextField *view = (UITextField *)(((RCTBaseTextInputView*)[_bridge.uiManager viewForReactTag:reactTag]).backedTextInputView);
    UITextRange* range = view.selectedTextRange;
    
    if ([view comparePosition:range.start toPosition:range.end] == 0) {
        NSInteger startOffset = [view offsetFromPosition:view.beginningOfDocument toPosition:range.start];

        NSMutableArray *characters = [NSMutableArray array];
        NSString *test = view.text;
        [test enumerateSubstringsInRange:NSMakeRange(0, test.length) options:NSStringEnumerationByComposedCharacterSequences usingBlock:^(NSString * _Nullable substring, NSRange substringRange, NSRange enclosingRange, BOOL * _Nonnull stop) {
            [characters addObject:substring];
        }];
//        NSLog(@"%ld",characters.count);
        NSInteger offset = 1;
        NSInteger len = 0;
        NSString*selectedObj = nil;
        for (NSString*str in characters) {
            len += str.length;
            if (len == startOffset) {
                selectedObj = str;
                break;
            }
        }
        
        if (selectedObj) {
            offset = selectedObj.length;
        }
        range = [view textRangeFromPosition:[view positionFromPosition:range.start offset:-(offset)] toPosition:range.start];
    }
    
    [view replaceRange:range withText:@""];
}

RCT_EXPORT_METHOD(doDelete:(nonnull NSNumber *)reactTag) {
    UITextField *view = (UITextField *)(((RCTBaseTextInputView*)[_bridge.uiManager viewForReactTag:reactTag]).backedTextInputView);
    
    UITextRange* range = view.selectedTextRange;
    if ([view comparePosition:range.start toPosition:range.end] == 0) {
        range = [view textRangeFromPosition:range.start toPosition:[view positionFromPosition: range.start offset: 1]];
    }
    [view replaceRange:range withText:@""];
}

RCT_EXPORT_METHOD(moveLeft:(nonnull NSNumber *)reactTag) {
    UITextField *view = (UITextField *)(((RCTBaseTextInputView*)[_bridge.uiManager viewForReactTag:reactTag]).backedTextInputView);
    
    UITextRange* range = view.selectedTextRange;
    UITextPosition* position = range.start;
    
    if ([view comparePosition:range.start toPosition:range.end] == 0) {
        position = [view positionFromPosition: position offset: -1];
    }
    
    view.selectedTextRange = [view textRangeFromPosition: position toPosition:position];
}

RCT_EXPORT_METHOD(moveRight:(nonnull NSNumber *)reactTag) {
    UITextField *view = (UITextField *)(((RCTBaseTextInputView*)[_bridge.uiManager viewForReactTag:reactTag]).backedTextInputView);
    
    UITextRange* range = view.selectedTextRange;
    UITextPosition* position = range.end;
    
    if ([view comparePosition:range.start toPosition:range.end] == 0) {
        position = [view positionFromPosition: position offset: 1];
    }
    
    view.selectedTextRange = [view textRangeFromPosition: position toPosition:position];
}

RCT_EXPORT_METHOD(switchSystemKeyboard:(nonnull NSNumber*) reactTag) {
    UITextField *view = (UITextField *)(((RCTBaseTextInputView*)[_bridge.uiManager viewForReactTag:reactTag]).backedTextInputView);
    
    UIView* inputView = view.inputView;
    view.inputView = nil;
    [view reloadInputViews];
    view.inputView = inputView;
}

RCT_EXPORT_METHOD(clearAll:(nonnull NSNumber *)reactTag){
    UITextField *view = (UITextField *)(((RCTBaseTextInputView*)[_bridge.uiManager viewForReactTag:reactTag]).backedTextInputView);
    
    UITextRange* range = view.selectedTextRange;
    if(range.end > 0) {
        range = [view textRangeFromPosition:0 toPosition:range.end];
        [view replaceRange:range withText:@""];
    }
}

@end