From 3a28941c0445a61ce53b11c2755e8256f2a88a92 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E7=8E=8B=E5=8A=B2=E9=B9=8F?= <jingpeng.wang@outlook.com>
Date: Thu, 25 Aug 2022 14:47:11 +0800
Subject: [PATCH] iOS: implement flowlayout drag

---
 .../Pod/Classes/Shader/DoricFlowLayoutNode.m  | 54 +++++++++++++++++++
 1 file changed, 54 insertions(+)

diff --git a/doric-iOS/Pod/Classes/Shader/DoricFlowLayoutNode.m b/doric-iOS/Pod/Classes/Shader/DoricFlowLayoutNode.m
index 55089ce9..20fcd00b 100644
--- a/doric-iOS/Pod/Classes/Shader/DoricFlowLayoutNode.m
+++ b/doric-iOS/Pod/Classes/Shader/DoricFlowLayoutNode.m
@@ -173,6 +173,13 @@ @interface DoricFlowLayoutNode () <UICollectionViewDataSource, UICollectionViewD
 @property(nonatomic, copy) NSString *onScrollEndFuncId;
 @property(nonatomic, strong) DoricJSDispatcher *jsDispatcher;
 @property(nonatomic, assign) NSInteger loadAnchor;
+
+@property(nonatomic, strong) UILongPressGestureRecognizer *longPress;
+@property(nonatomic, strong) NSIndexPath *initialDragIndexPath;
+@property(nonatomic, strong) NSIndexPath *currentDragIndexPath;
+@property(nonatomic, copy) NSString *beforeDraggingFuncId;
+@property(nonatomic, copy) NSString *onDraggingFuncId;
+@property(nonatomic, copy) NSString *onDraggedFuncId;
 @end
 
 @implementation DoricFlowLayoutNode
@@ -202,9 +209,44 @@ - (UICollectionView *)build {
                 if (@available(iOS 11, *)) {
                     it.contentInsetAdjustmentBehavior = UIScrollViewContentInsetAdjustmentNever;
                 }
+        
+                self.longPress = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(longPressAction:)];
+                [it addGestureRecognizer:self.longPress];
+                [self.longPress setEnabled:NO];
             }];
 }
 
+- (void)longPressAction:(UILongPressGestureRecognizer *)sender {
+    CGPoint locationInView = [sender locationInView:self.view];
+    NSIndexPath *indexPath = [self.view indexPathForItemAtPoint:locationInView];
+    if (sender.state == UIGestureRecognizerStateBegan) {
+        if (indexPath != nil) {
+            self.initialDragIndexPath = indexPath;
+            self.currentDragIndexPath = indexPath;
+            if (self.beforeDraggingFuncId != nil) {
+                [self callJSResponse:self.beforeDraggingFuncId, @(indexPath.row), nil];
+            }
+        }
+    } else if (sender.state == UIGestureRecognizerStateChanged) {
+        if ((indexPath != nil) && (indexPath != self.currentDragIndexPath)) {
+            NSString *fromValue = self.itemViewIds[@(self.currentDragIndexPath.row)];
+            NSString *toValue = self.itemViewIds[@(indexPath.row)];
+            self.itemViewIds[@(self.currentDragIndexPath.row)] = toValue;
+            self.itemViewIds[@(indexPath.row)] = fromValue;
+
+            [self.view moveItemAtIndexPath:self.currentDragIndexPath toIndexPath:indexPath];
+            if (self.onDraggingFuncId != nil) {
+                [self callJSResponse:self.onDraggingFuncId, @(self.currentDragIndexPath.row), @(indexPath.row), nil];
+            }
+            self.currentDragIndexPath = indexPath;
+        }
+    } else if (sender.state == UIGestureRecognizerStateEnded) {
+        if (self.onDraggedFuncId != nil) {
+            [self callJSResponse:self.onDraggedFuncId, @(self.initialDragIndexPath.row), @(self.currentDragIndexPath.row), nil];
+        }
+    }
+}
+
 - (void)blendView:(UICollectionView *)view forPropName:(NSString *)name propValue:(id)prop {
     if ([@"scrollable" isEqualToString:name]) {
         self.view.scrollEnabled = [prop boolValue];
@@ -249,6 +291,15 @@ - (void)blendView:(UICollectionView *)view forPropName:(NSString *)name propValu
         self.onScrollFuncId = prop;
     } else if ([@"onScrollEnd" isEqualToString:name]) {
         self.onScrollEndFuncId = prop;
+    } else if ([@"canDrag" isEqualToString:name]) {
+        bool canDrag = [prop boolValue];
+        [self.longPress setEnabled:canDrag];
+    } else if ([@"beforeDragging" isEqualToString:name]) {
+        self.beforeDraggingFuncId = prop;
+    } else if ([@"onDragging" isEqualToString:name]) {
+        self.onDraggingFuncId = prop;
+    } else if ([@"onDragged" isEqualToString:name]) {
+        self.onDraggedFuncId = prop;
     } else {
         [super blendView:view forPropName:name propValue:prop];
     }
@@ -542,6 +593,9 @@ - (void)reset {
     self.loadMoreViewId = nil;
     self.onScrollFuncId = nil;
     self.onScrollEndFuncId = nil;
+    self.beforeDraggingFuncId = nil;
+    self.onDraggingFuncId = nil;
+    self.onDraggedFuncId = nil;
     self.loadMore = NO;
 }