Add folder tree

src/folder.rs

@@ -0,0 +1,218 @@
+use std::{
+    fs::read_dir,
+    mem,
+    ops::Deref,
+    path::{Path, PathBuf},
+    sync::mpsc,
+    thread,
+};
+
+use egui::{Response, Ui};
+use eyre::{Context, OptionExt, eyre};
+use serde::{Deserialize, Serialize};
+
+pub enum Folder {
+    NotLoaded {
+        name: String,
+        path: PathBuf,
+    },
+    Loading {
+        name: String,
+        path: PathBuf,
+        recv: mpsc::Receiver<LoadedFolder>,
+    },
+    Loaded(LoadedFolder),
+}
+
+pub struct LoadedFolder {
+    pub name: String,
+    pub path: PathBuf,
+    pub child_folders: Vec<Folder>,
+    pub child_files: Vec<File>,
+}
+
+pub struct File {
+    pub name: String,
+    pub path: PathBuf,
+}
+
+pub struct FolderResponse<'a> {
+    inner: Response,
+    pub open_file: Option<&'a Path>,
+}
+
+impl Deref for FolderResponse<'_> {
+    type Target = Response;
+
+    fn deref(&self) -> &Self::Target {
+        &self.inner
+    }
+}
+
+impl LoadedFolder {
+    pub fn show<'a>(&'a mut self, ui: &mut Ui) -> FolderResponse<'a> {
+        let mut open_file = None;
+        let inner = ui
+            .collapsing(&self.name, |ui| {
+                for folder in &mut self.child_folders {
+                    open_file = open_file.or(folder.show(ui).open_file);
+                }
+
+                for file in &mut self.child_files {
+                    if ui.button(&file.name).clicked() {
+                        open_file = Some(file.path.as_path())
+                    };
+                }
+            })
+            .header_response;
+
+        FolderResponse { inner, open_file }
+    }
+
+    fn load(path: PathBuf) -> eyre::Result<Self> {
+        let name = path
+            .file_name()
+            .ok_or_eyre("Path is missing a file-name")?
+            .to_string_lossy()
+            .to_string();
+
+        let mut child_folders = vec![];
+        let mut child_files = vec![];
+
+        for entry in read_dir(&path).with_context(|| eyre!("Couldn't read dir {path:?}"))? {
+            let entry = entry.with_context(|| eyre!("Couldn't read dir {path:?}"))?;
+            let path = entry.path();
+            let name = path
+                .file_name()
+                .ok_or_eyre("Path is missing a file-name")?
+                .to_string_lossy()
+                .to_string();
+
+            let file_type = entry.file_type()?;
+
+            if file_type.is_symlink() {
+                log::error!("Symlinks not yet supported, skipping {path:?}");
+                continue;
+            } else if file_type.is_file() {
+                child_files.push(File { name, path });
+            } else if file_type.is_dir() {
+                child_folders.push(Folder::NotLoaded { name, path });
+            }
+        }
+
+        let folder = LoadedFolder {
+            name,
+            path,
+            child_folders,
+            child_files,
+        };
+
+        Ok(folder)
+    }
+}
+
+impl Folder {
+    fn load(&mut self, ui: &mut Ui) -> Option<&mut LoadedFolder> {
+        if let Folder::NotLoaded { name, path } = self {
+            let (tx, rx) = mpsc::channel();
+
+            {
+                let path = path.clone();
+                let ctx = ui.ctx().clone();
+                thread::spawn(move || match LoadedFolder::load(path) {
+                    Err(e) => log::error!("Failed to load folder: {e}"),
+                    Ok(folder) => {
+                        let _ = tx.send(folder);
+                        ctx.request_repaint();
+                    }
+                });
+            }
+
+            *self = Folder::Loading {
+                name: mem::take(name),
+                path: mem::take(path),
+                recv: rx,
+            };
+        }
+
+        if let Folder::Loading { recv, .. } = self {
+            match recv.try_recv() {
+                Ok(folder) => *self = Folder::Loaded(folder),
+                Err(_) => return None,
+            }
+        }
+
+        let Folder::Loaded(folder) = self else {
+            unreachable!()
+        };
+
+        Some(folder)
+    }
+
+    pub fn show<'a>(&'a mut self, ui: &mut Ui) -> FolderResponse<'a> {
+        self.load(ui);
+
+        if let Folder::Loaded(folder) = self {
+            return folder.show(ui);
+        }
+
+        FolderResponse {
+            inner: ui.label(self.name()),
+            open_file: None,
+        }
+    }
+
+    pub fn path(&self) -> &Path {
+        match self {
+            Folder::NotLoaded { path, .. } => path,
+            Folder::Loading { path, .. } => path,
+            Folder::Loaded(folder) => &folder.path,
+        }
+    }
+
+    pub fn name(&self) -> &str {
+        match self {
+            Folder::NotLoaded { name, .. } => name,
+            Folder::Loading { name, .. } => name,
+            Folder::Loaded(folder) => &folder.name,
+        }
+    }
+
+    pub fn unload(&mut self) {
+        let (name, path) = match self {
+            Folder::NotLoaded { .. } => return,
+            Folder::Loading { name, path, .. } => (name, path),
+            Folder::Loaded(folder) => (&mut folder.name, &mut folder.path),
+        };
+
+        *self = Folder::NotLoaded {
+            name: mem::take(name),
+            path: mem::take(path),
+        }
+    }
+}
+
+impl Serialize for Folder {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: serde::Serializer,
+    {
+        self.path().serialize(serializer)
+    }
+}
+
+impl<'de> Deserialize<'de> for Folder {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: serde::Deserializer<'de>,
+    {
+        use serde::de::Error;
+        let path = PathBuf::deserialize(deserializer)?;
+        let name = path
+            .file_name()
+            .ok_or(D::Error::custom("Path is missing a file-name"))?
+            .to_string_lossy()
+            .to_string();
+        Ok(Folder::NotLoaded { name, path })
+    }
+}