From 89d234a4d57167e6e29138c1db39f8a7ede41ac4 Mon Sep 17 00:00:00 2001
From: Benign X <1341398182@qq.com>
Date: Sun, 1 Dec 2024 23:37:17 +0800
Subject: [PATCH] =?UTF-8?q?=E2=9C=A8(ImageShower):=20add=20file=20drag=20a?=
 =?UTF-8?q?nd=20drop=20functionality?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

This update introduces the ability to drag and drop files into the image shower, displaying information about the dropped files and handling their data. The new `ui_file_drag_and_drop` method manages the UI for this feature, including visual feedback during the drag operation and a window to show the details of the dropped files.

Signed-off-by: Benign X <1341398182@qq.com>
---
 src/image_shower.rs | 84 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 84 insertions(+)

diff --git a/src/image_shower.rs b/src/image_shower.rs
index 7521293..915dc14 100644
--- a/src/image_shower.rs
+++ b/src/image_shower.rs
@@ -39,6 +39,8 @@ struct MyEguiApp {
     height: u32,
     image_data: Option<Vec<Color32>>,
 
+    dropped_files: Vec<egui::DroppedFile>,
+
     context: AppContext,
 }
 
@@ -75,6 +77,8 @@ impl MyEguiApp {
             height,
             image_data,
 
+            dropped_files: Default::default(),
+
             context,
         }
     }
@@ -196,9 +200,89 @@ impl eframe::App for MyEguiApp {
                 );
             }
         });
+
+        self.ui_file_drag_and_drop(ctx);
     }
 
     fn save(&mut self, storage: &mut dyn eframe::Storage) {
         eframe::set_value(storage, eframe::APP_KEY, &self.context);
     }
 }
+
+impl MyEguiApp {
+    fn ui_file_drag_and_drop(&mut self, ctx: &egui::Context) {
+        use std::fmt::Write as _;
+
+        if !ctx.input(|i| i.raw.hovered_files.is_empty()) {
+            let text = ctx.input(|i| {
+                let mut text = "Dropping files:\n".to_owned();
+                for file in &i.raw.hovered_files {
+                    if let Some(path) = &file.path {
+                        write!(text, "\n{}", path.display()).ok();
+                    } else if !file.mime.is_empty() {
+                        write!(text, "\n{}", file.mime).ok();
+                    } else {
+                        text += "\n???";
+                    }
+                }
+                text
+            });
+
+            let painter = ctx.layer_painter(egui::LayerId::new(
+                egui::Order::Foreground,
+                egui::Id::new("file_drop_target"),
+            ));
+
+            let screen_rect = ctx.screen_rect();
+            painter.rect_filled(screen_rect, 0.0, Color32::from_black_alpha(192));
+            painter.text(
+                screen_rect.center(),
+                egui::Align2::CENTER_CENTER,
+                text,
+                egui::TextStyle::Heading.resolve(&ctx.style()),
+                Color32::WHITE,
+            );
+        }
+
+        // Collect dropped files:
+        ctx.input(|i| {
+            if !i.raw.dropped_files.is_empty() {
+                self.dropped_files = i.raw.dropped_files.clone();
+            }
+        });
+
+        // Show dropped files (if any):
+        if !self.dropped_files.is_empty() {
+            let mut open = true;
+            egui::Window::new("Dropped files")
+                .open(&mut open)
+                .show(ctx, |ui| {
+                    for file in &self.dropped_files {
+                        let mut info = if let Some(path) = &file.path {
+                            path.display().to_string()
+                        } else if !file.name.is_empty() {
+                            file.name.clone()
+                        } else {
+                            "???".to_owned()
+                        };
+
+                        let mut additional_info = vec![];
+                        if !file.mime.is_empty() {
+                            additional_info.push(format!("type: {}", file.mime));
+                        }
+                        if let Some(bytes) = &file.bytes {
+                            additional_info.push(format!("{} bytes", bytes.len()));
+                        }
+                        if !additional_info.is_empty() {
+                            info += &format!(" ({})", additional_info.join(", "));
+                        }
+
+                        ui.label(info);
+                    }
+                });
+            if !open {
+                self.dropped_files.clear();
+            }
+        }
+    }
+}