melib: rework mail events

closes #39

melib/src/mailbox/backends/maildir/backend.rs

@@ -20,18 +20,19 @@
  */
 
 extern crate bincode;
+extern crate fnv;
+extern crate notify;
 extern crate xdg;
 
+use super::{MaildirFolder, MaildirOp};
 use async::*;
 use conf::AccountSettings;
-use error::{MeliError, Result};
+use error::Result;
 use mailbox::backends::{
     BackendFolder, BackendOp, Folder, MailBackend, RefreshEvent, RefreshEventConsumer,
+    RefreshEventKind::*,
 };
-use mailbox::email::parser;
+use mailbox::email::{Envelope, EnvelopeHash};
-use mailbox::email::{Envelope, Flag};
-
-extern crate notify;
 
 use self::notify::{watcher, DebouncedEvent, RecursiveMode, Watcher};
 use std::time::Duration;
@@ -42,148 +43,84 @@ use std::sync::mpsc::channel;
 //use std::time::Duration;
 use std::thread;
 extern crate crossbeam;
-use memmap::{Mmap, Protection};
+use self::fnv::{FnvHashMap, FnvHasher};
 use std::collections::hash_map::DefaultHasher;
+use std::ffi::OsStr;
 use std::fs;
 use std::hash::{Hash, Hasher};
 use std::io;
 use std::io::Read;
 use std::os::unix::ffi::OsStrExt;
-use std::path::{Path, PathBuf};
+use std::path::{Component, Path, PathBuf};
 use std::result;
 use std::sync::{Arc, Mutex};
-extern crate fnv;
-use self::fnv::{FnvHashMap, FnvHasher};
 
-/// `BackendOp` implementor for Maildir
+type HashIndex = Arc<Mutex<FnvHashMap<EnvelopeHash, (usize, PathBuf)>>>;
-#[derive(Debug)]
-pub struct MaildirOp {
-    hash_index: Arc<Mutex<FnvHashMap<u64, (usize, PathBuf)>>>,
-    hash: u64,
-    slice: Option<Mmap>,
-}
-
-impl Clone for MaildirOp {
-    fn clone(&self) -> Self {
-        MaildirOp {
-            hash_index: self.hash_index.clone(),
-            hash: self.hash,
-            slice: None,
-        }
-    }
-}
-
-impl MaildirOp {
-    pub fn new(hash: u64, hash_index: Arc<Mutex<FnvHashMap<u64, (usize, PathBuf)>>>) -> Self {
-        MaildirOp {
-            hash_index,
-            hash,
-            slice: None,
-        }
-    }
-    fn path(&self) -> PathBuf {
-        let hash_index = self.hash_index.clone();
-        let map = hash_index.lock().unwrap();
-        map.get(&self.hash).unwrap().1.clone()
-    }
-}
-
-impl<'a> BackendOp for MaildirOp {
-    fn description(&self) -> String {
-        format!("Path of file: {}", self.path().display())
-    }
-    fn as_bytes(&mut self) -> Result<&[u8]> {
-        if self.slice.is_none() {
-            self.slice = Some(Mmap::open_path(self.path(), Protection::Read)?);
-        }
-        /* Unwrap is safe since we use ? above. */
-        Ok(unsafe { self.slice.as_ref().unwrap().as_slice() })
-    }
-    fn fetch_headers(&mut self) -> Result<&[u8]> {
-        let raw = self.as_bytes()?;
-        let result = parser::headers_raw(raw).to_full_result()?;
-        Ok(result)
-    }
-    fn fetch_body(&mut self) -> Result<&[u8]> {
-        let raw = self.as_bytes()?;
-        let result = parser::headers_raw(raw).to_full_result()?;
-        Ok(result)
-    }
-    fn fetch_flags(&self) -> Flag {
-        let mut flag = Flag::default();
-        let path = self.path();
-        let path = path.to_str().unwrap(); // Assume UTF-8 validity
-        if !path.contains(":2,") {
-            return flag;
-        }
-
-        for f in path.chars().rev() {
-            match f {
-                ',' => break,
-                'D' => flag |= Flag::DRAFT,
-                'F' => flag |= Flag::FLAGGED,
-                'P' => flag |= Flag::PASSED,
-                'R' => flag |= Flag::REPLIED,
-                'S' => flag |= Flag::SEEN,
-                'T' => flag |= Flag::TRASHED,
-                _ => panic!(),
-            }
-        }
-
-        flag
-    }
-
-    fn set_flag(&mut self, envelope: &mut Envelope, f: &Flag) -> Result<()> {
-        let path = self.path();
-        let path = path.to_str().unwrap(); // Assume UTF-8 validity
-        let idx: usize = path
-            .rfind(":2,")
-            .ok_or_else(|| MeliError::new(format!("Invalid email filename: {:?}", self)))?
-            + 3;
-        let mut new_name: String = path[..idx].to_string();
-        let mut flags = self.fetch_flags();
-        if !(flags & *f).is_empty() {
-            return Ok(());
-        }
-        flags.toggle(*f);
-        if !(flags & Flag::DRAFT).is_empty() {
-            new_name.push('D');
-        }
-        if !(flags & Flag::FLAGGED).is_empty() {
-            new_name.push('F');
-        }
-        if !(flags & Flag::PASSED).is_empty() {
-            new_name.push('P');
-        }
-        if !(flags & Flag::REPLIED).is_empty() {
-            new_name.push('R');
-        }
-        if !(flags & Flag::SEEN).is_empty() {
-            new_name.push('S');
-        }
-        if !(flags & Flag::TRASHED).is_empty() {
-            new_name.push('T');
-        }
-
-        fs::rename(&path, &new_name)?;
-        let hash = envelope.hash();
-        let hash_index = self.hash_index.clone();
-        let mut map = hash_index.lock().unwrap();
-        map.get_mut(&hash).unwrap().1 = PathBuf::from(new_name);
-        Ok(())
-    }
-}
 
 /// Maildir backend https://cr.yp.to/proto/maildir.html
 #[derive(Debug)]
 pub struct MaildirType {
     name: String,
     folders: Vec<MaildirFolder>,
-    hash_index: Arc<Mutex<FnvHashMap<u64, (usize, PathBuf)>>>,
+    hash_index: HashIndex,
 
     path: PathBuf,
 }
 
+macro_rules! path_is_new {
+    ($path:expr) => {
+        if $path.is_dir() {
+            false
+        } else {
+            let mut iter = $path.components().rev();
+            iter.next();
+            iter.next();
+            iter.next() == Some(Component::Normal(OsStr::new("new")))
+        }
+    };
+}
+macro_rules! get_path_hash {
+    ($path:expr) => {{
+        if $path.is_dir() {
+            if $path.ends_with("cur") | $path.ends_with("new") {
+                $path.pop();
+            }
+        } else {
+            $path.pop();
+            $path.pop();
+        };
+        eprintln!(" got event in {}", $path.display());
+
+        let mut hasher = DefaultHasher::new();
+        $path.hash(&mut hasher);
+        hasher.finish()
+    }};
+}
+
+fn get_file_hash(file: &Path) -> EnvelopeHash {
+    let mut buf = Vec::new();
+    let mut f = fs::File::open(&file).unwrap_or_else(|_| panic!("Can't open {}", file.display()));
+    f.read_to_end(&mut buf)
+        .unwrap_or_else(|_| panic!("Can't read {}", file.display()));
+    let mut hasher = FnvHasher::default();
+    hasher.write(file.as_os_str().as_bytes());
+    hasher.write(&buf);
+    hasher.finish()
+}
+
+fn move_to_cur(p: PathBuf) {
+    let mut new = p.clone();
+    {
+        let file_name = p.file_name().unwrap();
+        new.pop();
+        new.pop();
+
+        new.push("cur");
+        new.push(file_name);
+    }
+    fs::rename(p, new).unwrap();
+}
+
 impl MailBackend for MaildirType {
     fn folders(&self) -> Vec<Folder> {
         self.folders.iter().map(|f| f.clone()).collect()
@@ -194,6 +131,8 @@ impl MailBackend for MaildirType {
     fn watch(&self, sender: RefreshEventConsumer) -> Result<()> {
         let (tx, rx) = channel();
         let mut watcher = watcher(tx, Duration::from_secs(1)).unwrap();
+        let root_path = self.path.to_path_buf();
+        let cache_dir = xdg::BaseDirectories::with_profile("meli", &self.name).unwrap();
         for f in &self.folders {
             if f.is_valid().is_err() {
                 continue;
@@ -206,6 +145,7 @@ impl MailBackend for MaildirType {
             p.push("new");
             watcher.watch(&p, RecursiveMode::NonRecursive).unwrap();
         }
+        let map = self.hash_index.clone();
         thread::Builder::new()
             .name("folder watch".to_string())
             .spawn(move || {
@@ -213,26 +153,127 @@ impl MailBackend for MaildirType {
                 let _watcher = watcher;
                 loop {
                     match rx.recv() {
+                        /*
+                         * Event types:
+                         *
+                         * pub enum RefreshEventKind {
+                         *     Update(EnvelopeHash, Envelope), // Old hash, new envelope
+                         *     Create(Envelope),
+                         *     Remove(EnvelopeHash),
+                         *     Rescan,
+                         * }
+                         */
                         Ok(event) => match event {
-                            DebouncedEvent::Create(mut pathbuf)
+                            /* Create */
-                            | DebouncedEvent::Remove(mut pathbuf) => {
+                            DebouncedEvent::Create(mut pathbuf) => {
-                                if pathbuf.is_dir() {
+                                if path_is_new!(pathbuf) {
-                                    if pathbuf.ends_with("cur") | pathbuf.ends_with("new") {
+                                    move_to_cur(pathbuf);
-                                        pathbuf.pop();
+                                    continue;
-                                    }
+                                }
+                                let file_name = pathbuf
+                                    .as_path()
+                                    .strip_prefix(&root_path)
+                                    .unwrap()
+                                    .to_path_buf();
+                                if let Some(env) = add_path_to_index(
+                                    &map,
+                                    pathbuf.as_path(),
+                                    &cache_dir,
+                                    file_name,
+                                ) {
+                                    sender.send(RefreshEvent {
+                                        hash: get_path_hash!(pathbuf),
+                                        kind: Create(env),
+                                    });
                                 } else {
-                                    pathbuf.pop();
+                                    continue;
-                                    pathbuf.pop();
+                                }
+                            }
+                            /* Update */
+                            DebouncedEvent::NoticeWrite(mut pathbuf)
+                            | DebouncedEvent::Write(mut pathbuf) => {
+                                let file_name = pathbuf
+                                    .as_path()
+                                    .strip_prefix(&root_path)
+                                    .unwrap()
+                                    .to_path_buf();
+                                /* Linear search in hash_index to find old hash */
+                                let old_hash: EnvelopeHash = {
+                                    let mut map_lock = map.lock().unwrap();
+                                    if let Some((k, v)) =
+                                        map_lock.iter_mut().find(|(_, v)| v.1 == pathbuf)
+                                    {
+                                        v.1 = pathbuf.clone();
+                                        *k
+                                    } else {
+                                        /* Did we just miss a Create event? In any case, create
+                                         * envelope. */
+                                        if let Some(env) = add_path_to_index(
+                                            &map,
+                                            pathbuf.as_path(),
+                                            &cache_dir,
+                                            file_name,
+                                        ) {
+                                            sender.send(RefreshEvent {
+                                                hash: get_path_hash!(pathbuf),
+                                                kind: Create(env),
+                                            });
+                                        }
+                                        return;
+                                    }
+                                };
+                                let new_hash: EnvelopeHash = get_file_hash(pathbuf.as_path());
+                                let mut map_lock = map.lock().unwrap();
+                                if map_lock.get_mut(&new_hash).is_none() {
+                                    let op = Box::new(MaildirOp::new(new_hash, map.clone()));
+                                    if let Some(env) = Envelope::from_token(op, new_hash) {
+                                        map_lock.insert(new_hash, (0, pathbuf.clone()));
+
+                                        /* Send Write notice */
+
+                                        sender.send(RefreshEvent {
+                                            hash: get_path_hash!(pathbuf),
+                                            kind: Update(old_hash, env),
+                                        });
+                                    }
+                                }
+                            }
+                            /* Remove */
+                            DebouncedEvent::NoticeRemove(mut pathbuf)
+                            | DebouncedEvent::Remove(mut pathbuf) => {
+                                let map = map.lock().unwrap();
+                                let hash: EnvelopeHash = if let Some((k, _)) =
+                                    map.iter().find(|(_, v)| v.1 == pathbuf)
+                                {
+                                    *k
+                                } else {
+                                    continue;
                                 };
-                                eprintln!(" got event in {}", pathbuf.display());
 
-                                let mut hasher = DefaultHasher::new();
-                                pathbuf.hash(&mut hasher);
                                 sender.send(RefreshEvent {
-                                    folder: format!("{}", pathbuf.display()),
+                                    hash: get_path_hash!(pathbuf),
-                                    hash: hasher.finish(),
+                                    kind: Remove(hash),
                                 });
                             }
+                            /* Envelope hasn't changed, so handle this here */
+                            DebouncedEvent::Rename(_, mut dest) => {
+                                let new_hash: EnvelopeHash = get_file_hash(dest.as_path());
+                                let mut map = map.lock().unwrap();
+                                if let Some(v) = map.get_mut(&new_hash) {
+                                    v.1 = dest;
+                                } else {
+                                    /* Maybe a re-read should be triggered here just to be safe. */
+                                    sender.send(RefreshEvent {
+                                        hash: get_path_hash!(dest),
+                                        kind: Rescan,
+                                    });
+                                }
+                            }
+                            /* Trigger rescan of folder */
+                            DebouncedEvent::Rescan => {
+                                /* Actually should rescan all folders */
+                                unreachable!("Unimplemented: rescan of all folders in MaildirType")
+                            }
                             _ => {}
                         },
                         Err(e) => eprintln!("watch error: {:?}", e),
@@ -241,7 +282,7 @@ impl MailBackend for MaildirType {
             })?;
         Ok(())
     }
-    fn operation(&self, hash: u64) -> Box<BackendOp> {
+    fn operation(&self, hash: EnvelopeHash) -> Box<BackendOp> {
         Box::new(MaildirOp::new(hash, self.hash_index.clone()))
     }
 }
@@ -296,12 +337,12 @@ impl MaildirType {
         }
     }
     fn owned_folder_idx(&self, folder: &Folder) -> usize {
-        for (idx, f) in self.folders.iter().enumerate() {
+        self.folders
-            if f.hash() == folder.hash() {
+            .iter()
-                return idx;
+            .enumerate()
-            }
+            .find(|(_, f)| f.hash() == folder.hash())
-        }
+            .unwrap()
-        unreachable!()
+            .0
     }
 
     pub fn multicore(&mut self, cores: usize, folder: &Folder) -> Async<Result<Vec<Envelope>>> {
@@ -321,6 +362,15 @@ impl MaildirType {
                 .name(name.clone())
                 .spawn(move || {
                     let cache_dir = cache_dir.clone();
+                    {
+                        path.push("new");
+                        for d in path.read_dir()? {
+                            if let Ok(p) = d {
+                                move_to_cur(p.path());
+                            }
+                        }
+                        path.pop();
+                    }
                     path.push("cur");
                     let iter = path.read_dir()?;
                     let count = path.read_dir()?.count();
@@ -382,20 +432,7 @@ impl MaildirType {
                                                 }
                                             }
                                             {
-                                                let hash = {
+                                                let hash = get_file_hash(file);
-                                                    let mut buf = Vec::new();
-                                                    let mut f = fs::File::open(&file)
-                                                        .unwrap_or_else(|_| {
-                                                            panic!("Can't open {}", file.display())
-                                                        });
-                                                    f.read_to_end(&mut buf).unwrap_or_else(|_| {
-                                                        panic!("Can't read {}", file.display())
-                                                    });
-                                                    let mut hasher = FnvHasher::default();
-                                                    hasher.write(file.as_os_str().as_bytes());
-                                                    hasher.write(&buf);
-                                                    hasher.finish()
-                                                };
                                                 {
                                                     let mut map = map.lock().unwrap();
                                                     if (*map).contains_key(&hash) {
@@ -454,67 +491,37 @@ impl MaildirType {
     }
 }
 
-#[derive(Debug, Default)]
+fn add_path_to_index(
-pub struct MaildirFolder {
+    map: &HashIndex,
-    hash: u64,
+    path: &Path,
-    name: String,
+    cache_dir: &xdg::BaseDirectories,
-    path: PathBuf,
+    file_name: PathBuf,
-    children: Vec<usize>,
+) -> Option<Envelope> {
-}
+    let env: Envelope;
-
+    let hash = get_file_hash(path);
-impl MaildirFolder {
+    {
-    pub fn new(path: String, file_name: String, children: Vec<usize>) -> Result<Self> {
+        let mut map = map.lock().unwrap();
-        let pathbuf = PathBuf::from(path);
+        if (*map).contains_key(&hash) {
-        let mut h = DefaultHasher::new();
+            return None;
-        pathbuf.hash(&mut h);
-
-        let ret = MaildirFolder {
-            hash: h.finish(),
-            name: file_name,
-            path: pathbuf,
-            children,
-        };
-        ret.is_valid()?;
-        Ok(ret)
-    }
-    pub fn path(&self) -> &Path {
-        self.path.as_path()
-    }
-    fn is_valid(&self) -> Result<()> {
-        let path = self.path();
-        let mut p = PathBuf::from(path);
-        for d in &["cur", "new", "tmp"] {
-            p.push(d);
-            if !p.is_dir() {
-                return Err(MeliError::new(format!(
-                    "{} is not a valid maildir folder",
-                    path.display()
-                )));
-            }
-            p.pop();
         }
-        Ok(())
+        (*map).insert(hash, (0, path.to_path_buf()));
-    }
-}
-impl BackendFolder for MaildirFolder {
-    fn hash(&self) -> u64 {
-        self.hash
-    }
-    fn name(&self) -> &str {
-        &self.name
-    }
-    fn change_name(&mut self, s: &str) {
-        self.name = s.to_string();
-    }
-    fn children(&self) -> &Vec<usize> {
-        &self.children
-    }
-    fn clone(&self) -> Folder {
-        Box::new(MaildirFolder {
-            hash: self.hash,
-            name: self.name.clone(),
-            path: self.path.clone(),
-            children: self.children.clone(),
-        })
     }
+    let op = Box::new(MaildirOp::new(hash, map.clone()));
+    if let Some(e) = Envelope::from_token(op, hash) {
+        if let Ok(cached) = cache_dir.place_cache_file(file_name) {
+            /* place result in cache directory */
+            let f = match fs::File::create(cached) {
+                Ok(f) => f,
+                Err(e) => {
+                    panic!("{}", e);
+                }
+            };
+            let writer = io::BufWriter::new(f);
+            bincode::serialize_into(writer, &e).unwrap();
+        }
+        env = e;
+    } else {
+        return None;
+    }
+    Some(env)
 }

melib/src/mailbox/backends/maildir/mod.rs

@@ -0,0 +1,225 @@
+/*
+ * meli - mailbox module.
+ *
+ * Copyright 2017 Manos Pitsidianakis
+ *
+ * This file is part of meli.
+ *
+ * meli is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * meli is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with meli. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+extern crate fnv;
+use self::fnv::FnvHashMap;
+
+mod backend;
+pub use self::backend::*;
+
+use error::{MeliError, Result};
+use mailbox::backends::*;
+use mailbox::email::parser;
+use mailbox::email::{Envelope, Flag};
+
+use memmap::{Mmap, Protection};
+use std::collections::hash_map::DefaultHasher;
+use std::fs;
+use std::hash::{Hash, Hasher};
+use std::path::{Path, PathBuf};
+use std::sync::{Arc, Mutex};
+
+/// `BackendOp` implementor for Maildir
+#[derive(Debug)]
+pub struct MaildirOp {
+    hash_index: Arc<Mutex<FnvHashMap<EnvelopeHash, (usize, PathBuf)>>>,
+    hash: EnvelopeHash,
+    slice: Option<Mmap>,
+}
+
+impl Clone for MaildirOp {
+    fn clone(&self) -> Self {
+        MaildirOp {
+            hash_index: self.hash_index.clone(),
+            hash: self.hash,
+            slice: None,
+        }
+    }
+}
+
+impl MaildirOp {
+    pub fn new(
+        hash: EnvelopeHash,
+        hash_index: Arc<Mutex<FnvHashMap<EnvelopeHash, (usize, PathBuf)>>>,
+    ) -> Self {
+        MaildirOp {
+            hash_index,
+            hash,
+            slice: None,
+        }
+    }
+    fn path(&self) -> PathBuf {
+        let hash_index = self.hash_index.clone();
+        let map = hash_index.lock().unwrap();
+        map.get(&self.hash).unwrap().1.clone()
+    }
+}
+
+impl<'a> BackendOp for MaildirOp {
+    fn description(&self) -> String {
+        format!("Path of file: {}", self.path().display())
+    }
+    fn as_bytes(&mut self) -> Result<&[u8]> {
+        if self.slice.is_none() {
+            self.slice = Some(Mmap::open_path(self.path(), Protection::Read)?);
+        }
+        /* Unwrap is safe since we use ? above. */
+        Ok(unsafe { self.slice.as_ref().unwrap().as_slice() })
+    }
+    fn fetch_headers(&mut self) -> Result<&[u8]> {
+        let raw = self.as_bytes()?;
+        let result = parser::headers_raw(raw).to_full_result()?;
+        Ok(result)
+    }
+    fn fetch_body(&mut self) -> Result<&[u8]> {
+        let raw = self.as_bytes()?;
+        let result = parser::headers_raw(raw).to_full_result()?;
+        Ok(result)
+    }
+    fn fetch_flags(&self) -> Flag {
+        let mut flag = Flag::default();
+        let path = self.path();
+        let path = path.to_str().unwrap(); // Assume UTF-8 validity
+        if !path.contains(":2,") {
+            return flag;
+        }
+
+        for f in path.chars().rev() {
+            match f {
+                ',' => break,
+                'D' => flag |= Flag::DRAFT,
+                'F' => flag |= Flag::FLAGGED,
+                'P' => flag |= Flag::PASSED,
+                'R' => flag |= Flag::REPLIED,
+                'S' => flag |= Flag::SEEN,
+                'T' => flag |= Flag::TRASHED,
+                _ => panic!(),
+            }
+        }
+
+        flag
+    }
+
+    fn set_flag(&mut self, envelope: &mut Envelope, f: &Flag) -> Result<()> {
+        let path = self.path();
+        let path = path.to_str().unwrap(); // Assume UTF-8 validity
+        let idx: usize = path
+            .rfind(":2,")
+            .ok_or_else(|| MeliError::new(format!("Invalid email filename: {:?}", self)))?
+            + 3;
+        let mut new_name: String = path[..idx].to_string();
+        let mut flags = self.fetch_flags();
+        if !(flags & *f).is_empty() {
+            return Ok(());
+        }
+        flags.toggle(*f);
+        if !(flags & Flag::DRAFT).is_empty() {
+            new_name.push('D');
+        }
+        if !(flags & Flag::FLAGGED).is_empty() {
+            new_name.push('F');
+        }
+        if !(flags & Flag::PASSED).is_empty() {
+            new_name.push('P');
+        }
+        if !(flags & Flag::REPLIED).is_empty() {
+            new_name.push('R');
+        }
+        if !(flags & Flag::SEEN).is_empty() {
+            new_name.push('S');
+        }
+        if !(flags & Flag::TRASHED).is_empty() {
+            new_name.push('T');
+        }
+
+        fs::rename(&path, &new_name)?;
+        let hash = envelope.hash();
+        let hash_index = self.hash_index.clone();
+        let mut map = hash_index.lock().unwrap();
+        map.get_mut(&hash).unwrap().1 = PathBuf::from(new_name);
+        Ok(())
+    }
+}
+
+#[derive(Debug, Default)]
+pub struct MaildirFolder {
+    hash: FolderHash,
+    name: String,
+    path: PathBuf,
+    children: Vec<usize>,
+}
+
+impl MaildirFolder {
+    pub fn new(path: String, file_name: String, children: Vec<usize>) -> Result<Self> {
+        let pathbuf = PathBuf::from(path);
+        let mut h = DefaultHasher::new();
+        pathbuf.hash(&mut h);
+
+        let ret = MaildirFolder {
+            hash: h.finish(),
+            name: file_name,
+            path: pathbuf,
+            children,
+        };
+        ret.is_valid()?;
+        Ok(ret)
+    }
+    pub fn path(&self) -> &Path {
+        self.path.as_path()
+    }
+    fn is_valid(&self) -> Result<()> {
+        let path = self.path();
+        let mut p = PathBuf::from(path);
+        for d in &["cur", "new", "tmp"] {
+            p.push(d);
+            if !p.is_dir() {
+                return Err(MeliError::new(format!(
+                    "{} is not a valid maildir folder",
+                    path.display()
+                )));
+            }
+            p.pop();
+        }
+        Ok(())
+    }
+}
+impl BackendFolder for MaildirFolder {
+    fn hash(&self) -> FolderHash {
+        self.hash
+    }
+    fn name(&self) -> &str {
+        &self.name
+    }
+    fn change_name(&mut self, s: &str) {
+        self.name = s.to_string();
+    }
+    fn children(&self) -> &Vec<usize> {
+        &self.children
+    }
+    fn clone(&self) -> Folder {
+        Box::new(MaildirFolder {
+            hash: self.hash,
+            name: self.name.clone(),
+            path: self.path.clone(),
+            children: self.children.clone(),
+        })
+    }
+}

melib/src/mailbox/backends/mod.rs

@@ -28,7 +28,7 @@ use error::Result;
 //use mailbox::backends::imap::ImapType;
 //use mailbox::backends::mbox::MboxType;
 use mailbox::backends::maildir::MaildirType;
-use mailbox::email::{Envelope, Flag};
+use mailbox::email::{Envelope, EnvelopeHash, Flag};
 use std::fmt;
 use std::fmt::Debug;
 
@@ -79,18 +79,27 @@ impl Backends {
     }
 }
 
+#[derive(Debug)]
+pub enum RefreshEventKind {
+    Update(EnvelopeHash, Envelope),
+    Create(Envelope),
+    Remove(FolderHash),
+    Rescan,
+}
+
+#[derive(Debug)]
 pub struct RefreshEvent {
-    hash: u64,
+    hash: FolderHash,
-    folder: String,
+    kind: RefreshEventKind,
 }
 
 impl RefreshEvent {
-    pub fn hash(&self) -> u64 {
+    pub fn hash(&self) -> FolderHash {
         self.hash
     }
-
+    pub fn kind(self) -> RefreshEventKind {
-    pub fn folder(&self) -> &str {
+        /* consumes self! */
-        self.folder.as_str()
+        self.kind
     }
 }
 
@@ -112,7 +121,7 @@ pub trait MailBackend: ::std::fmt::Debug {
     fn get(&mut self, folder: &Folder) -> Async<Result<Vec<Envelope>>>;
     fn watch(&self, sender: RefreshEventConsumer) -> Result<()>;
     fn folders(&self) -> Vec<Folder>;
-    fn operation(&self, hash: u64) -> Box<BackendOp>;
+    fn operation(&self, hash: EnvelopeHash) -> Box<BackendOp>;
     //login function
 }
 
@@ -191,7 +200,7 @@ impl fmt::Debug for BackendOpGenerator {
 }
 
 pub trait BackendFolder: Debug {
-    fn hash(&self) -> u64;
+    fn hash(&self) -> FolderHash;
     fn name(&self) -> &str;
     fn change_name(&mut self, &str);
     fn clone(&self) -> Folder;
@@ -204,7 +213,7 @@ struct DummyFolder {
 }
 
 impl BackendFolder for DummyFolder {
-    fn hash(&self) -> u64 {
+    fn hash(&self) -> FolderHash {
         0
     }
     fn name(&self) -> &str {
@@ -224,4 +233,5 @@ pub fn folder_default() -> Folder {
     })
 }
 
+pub type FolderHash = u64;
 pub type Folder = Box<BackendFolder>;

melib/src/mailbox/email/mod.rs

@@ -260,6 +260,9 @@ impl EnvelopeWrapper {
     }
 }
 
+pub type UnixTimestamp = u64;
+pub type EnvelopeHash = u64;
+
 /// `Envelope` represents all the data of an email we need to know.
 ///
 ///  Attachments (the email's body) is parsed on demand with `body`.
@@ -280,16 +283,16 @@ pub struct Envelope {
     in_reply_to: Option<MessageID>,
     references: Option<References>,
 
-    timestamp: u64,
+    timestamp: UnixTimestamp,
     thread: usize,
 
-    hash: u64,
+    hash: EnvelopeHash,
 
     flags: Flag,
 }
 
 impl Envelope {
-    pub fn new(hash: u64) -> Self {
+    pub fn new(hash: EnvelopeHash) -> Self {
         Envelope {
             date: String::new(),
             from: Vec::new(),
@@ -320,7 +323,7 @@ impl Envelope {
         }
         Err(MeliError::new("Couldn't parse mail."))
     }
-    pub fn from_token(mut operation: Box<BackendOp>, hash: u64) -> Option<Envelope> {
+    pub fn from_token(mut operation: Box<BackendOp>, hash: EnvelopeHash) -> Option<Envelope> {
         let mut e = Envelope::new(hash);
         e.flags = operation.fetch_flags();
         if let Ok(bytes) = operation.as_bytes() {
@@ -331,7 +334,7 @@ impl Envelope {
         }
         None
     }
-    pub fn hash(&self) -> u64 {
+    pub fn hash(&self) -> EnvelopeHash {
         self.hash
     }
     pub fn populate_headers(&mut self, bytes: &[u8]) -> Result<()> {
@@ -437,7 +440,7 @@ impl Envelope {
         let headers = operation.fetch_headers()?;
         self.populate_headers(headers)
     }
-    pub fn date(&self) -> u64 {
+    pub fn date(&self) -> UnixTimestamp {
         self.timestamp
     }
 
@@ -672,7 +675,7 @@ impl Envelope {
         self.thread = new_val;
     }
     pub fn set_datetime(&mut self, new_val: chrono::DateTime<chrono::FixedOffset>) -> () {
-        self.timestamp = new_val.timestamp() as u64;
+        self.timestamp = new_val.timestamp() as UnixTimestamp;
     }
     pub fn set_flag(&mut self, f: Flag, mut operation: Box<BackendOp>) -> Result<()> {
         operation.set_flag(self, &f)?;

melib/src/mailbox/mod.rs

@@ -95,4 +95,30 @@ impl Mailbox {
     pub fn thread(&self, i: usize) -> &Container {
         &self.threads[i]
     }
+
+    pub fn update(&mut self, old_hash: EnvelopeHash, envelope: Envelope) {
+        if let Some(i) = self.collection.iter().position(|e| e.hash() == old_hash) {
+            self.collection[i] = envelope;
+        } else {
+            panic!()
+        }
+    }
+
+    pub fn insert(&mut self, envelope: Envelope) -> &Envelope {
+        self.collection.push(envelope);
+        // TODO: Update threads.
+        eprintln!("Inserted envelope");
+        &self.collection[self.collection.len() - 1]
+    }
+
+    pub fn remove(&mut self, envelope_hash: EnvelopeHash) {
+        if let Some(i) = self
+            .collection
+            .iter()
+            .position(|e| e.hash() == envelope_hash)
+        {
+            self.collection.remove(i);
+        }
+        //   eprintln!("envelope_hash: {}\ncollection:\n{:?}", envelope_hash, self.collection);
+    }
 }

melib/src/mailbox/thread.rs

@@ -82,8 +82,6 @@ impl FromStr for SortOrder {
     }
 }
 
-type UnixTimestamp = u64;
-
 /// A `Container` struct is needed to describe the thread tree forest during creation of threads.
 /// Because of Rust's memory model, we store indexes of Envelopes inside a collection instead of
 /// references and every reference is passed through the `Container` owner (a `Vec<Container>`).

src/bin.rs

@@ -62,7 +62,7 @@ fn main() {
 
     /* Register some reasonably useful interfaces */
     let menu = Entity::from(Box::new(AccountMenu::new(&state.context.accounts)));
-    let listing = CompactListing::new();
+    let listing = PlainListing::new();
     let b = Entity::from(Box::new(listing));
     let tabs = Box::new(Tabbed::new(vec![Box::new(VSplit::new(menu, b, 90, true))]));
     let window = Entity::from(tabs);
@@ -138,8 +138,8 @@ fn main() {
                                 },
                             }
                         },
-                        ThreadEvent::RefreshMailbox { hash : h } => {
+                        ThreadEvent::RefreshMailbox(event) => {
-                            state.hash_to_folder(h);
+                            state.refresh_event(event);
                             state.redraw();
                         },
                         ThreadEvent::UIEvent(UIEventType::ChangeMode(f)) => {

ui/src/components/notifications.rs

@@ -40,10 +40,15 @@ impl fmt::Display for XDGNotifications {
 impl Component for XDGNotifications {
     fn draw(&mut self, _grid: &mut CellBuffer, _area: Area, _context: &mut Context) {}
     fn process_event(&mut self, event: &UIEvent, _context: &mut Context) -> bool {
-        if let UIEventType::Notification(ref t) = event.event_type {
+        if let UIEventType::Notification(ref title, ref body) = event.event_type {
             notify_Notification::new()
-                .summary("Refresh Event")
+                .summary(
-                .body(t)
+                    title
+                        .as_ref()
+                        .map(|v| v.as_str())
+                        .unwrap_or("Refresh Event"),
+                )
+                .body(body)
                 .icon("dialog-information")
                 .show()
                 .unwrap();

ui/src/state.rs

@@ -29,6 +29,8 @@
   */
 
 use super::*;
+use melib::backends::FolderHash;
+
 use chan::{Receiver, Sender};
 use fnv::FnvHashMap;
 use std::io::Write;
@@ -74,7 +76,7 @@ impl InputHandler {
 /// A context container for loaded settings, accounts, UI changes, etc.
 pub struct Context {
     pub accounts: Vec<Account>,
-    mailbox_hashes: FnvHashMap<u64, (usize, usize)>,
+    mailbox_hashes: FnvHashMap<FolderHash, (usize, usize)>,
     pub settings: Settings,
 
     pub runtime_settings: Settings,
@@ -101,34 +103,9 @@ impl Context {
         self.input.restore(self.sender.clone());
     }
     pub fn account_status(&mut self, idx_a: usize, idx_m: usize) -> result::Result<bool, usize> {
-        let s = self.accounts[idx_a].status(idx_m)?;
+        match self.accounts[idx_a].status(idx_m) {
-        match s {
+            Ok(()) => Ok(true),
-            LoadMailboxResult::New(event) => {
+            Err(n) => Err(n),
-                eprintln!("setting up notification");
-                let (idx_a, idx_m) = self.mailbox_hashes[&event.folder];
-                let subjects = {
-                    let mut ret = Vec::with_capacity(event.index.len());
-                    eprintln!("index is {:?}", &event.index);
-                    for &i in &event.index {
-                        ret.push(
-                            self.accounts[idx_a][idx_m].as_ref().unwrap().collection[i].subject(),
-                        );
-                    }
-                    ret
-                };
-                self.replies.push_back(UIEvent {
-                    id: 0,
-                    event_type: UIEventType::Notification(format!(
-                        "Update in {}/{}, indexes {:?}",
-                        self.accounts[idx_a].name(),
-                        self.accounts[idx_a][idx_m].as_ref().unwrap().folder.name(),
-                        subjects
-                    )),
-                });
-                Ok(true)
-            }
-            LoadMailboxResult::Loaded => Ok(true),
-            LoadMailboxResult::Refresh => Ok(false),
         }
     }
 }
@@ -285,9 +262,16 @@ impl State {
      * we match the hash to the index of the mailbox, request a reload
      * and startup a thread to remind us to poll it every now and then till it's finished.
      */
-    pub fn hash_to_folder(&mut self, hash: u64) {
+    pub fn refresh_event(&mut self, event: RefreshEvent) {
+        let hash = event.hash();
         if let Some(&(idxa, idxm)) = self.context.mailbox_hashes.get(&hash) {
-            self.context.accounts[idxa].reload(idxm);
+            if let Some(notification) = self.context.accounts[idxa].reload(event, idxm) {
+                self.context.replies.push_back(UIEvent {
+                    id: 0,
+                    event_type: notification,
+                });
+            }
+
             let (startup_tx, startup_rx) = chan::async();
             let startup_thread = {
                 let sender = self.context.sender.clone();

ui/src/types/accounts.rs

@@ -25,23 +25,14 @@
 
 use async::*;
 use conf::AccountConf;
-use mailbox::backends::{Backends, Folder, MailBackend, RefreshEventConsumer};
+use mailbox::backends::{
+    Backends, Folder, MailBackend, RefreshEvent, RefreshEventConsumer, RefreshEventKind,
+};
 use mailbox::*;
 use melib::error::Result;
-use std::mem;
 use std::ops::{Index, IndexMut};
 use std::result;
-
+use types::UIEventType::{self, Notification};
-pub enum LoadMailboxResult {
-    New(NewMailEvent),
-    Refresh,
-    Loaded,
-}
-
-pub struct NewMailEvent {
-    pub folder: u64,
-    pub index: Vec<usize>,
-}
 
 pub type Worker = Option<Async<Result<Vec<Envelope>>>>;
 
@@ -83,10 +74,36 @@ impl Account {
             backend,
         }
     }
-    pub fn reload(&mut self, idx: usize) {
+    pub fn reload(&mut self, event: RefreshEvent, idx: usize) -> Option<UIEventType> {
-        let ref_folders: Vec<Folder> = self.backend.folders();
+        let kind = event.kind();
-        let handle = self.backend.get(&ref_folders[idx]);
+        let mailbox: &mut Mailbox = self.folders[idx].as_mut().unwrap().as_mut().unwrap();
-        self.workers[idx] = Some(handle);
+        match kind {
+            RefreshEventKind::Update(old_hash, envelope) => {
+                mailbox.update(old_hash, envelope);
+            }
+            RefreshEventKind::Create(envelope) => {
+                let env: &Envelope = mailbox.insert(envelope);
+                let ref_folders: Vec<Folder> = self.backend.folders();
+                return Some(Notification(
+                    Some("New mail".into()),
+                    format!(
+                        "Subject: {:15}:\n{:15}\nFrom: {:15}",
+                        ref_folders[idx].name(),
+                        env.subject(),
+                        env.field_from_to_string()
+                    ),
+                ));
+            }
+            RefreshEventKind::Remove(envelope_hash) => {
+                mailbox.remove(envelope_hash);
+            }
+            RefreshEventKind::Rescan => {
+                let ref_folders: Vec<Folder> = self.backend.folders();
+                let handle = self.backend.get(&ref_folders[idx]);
+                self.workers[idx] = Some(handle);
+            }
+        }
+        return None;
     }
     pub fn watch(&self, r: RefreshEventConsumer) -> () {
         self.backend.watch(r).unwrap();
@@ -119,13 +136,7 @@ impl Account {
         &mut self.workers
     }
 
-    fn load_mailbox(
+    fn load_mailbox(&mut self, index: usize, envelopes: Result<Vec<Envelope>>) {
-        &mut self,
-        index: usize,
-        envelopes: Result<Vec<Envelope>>,
-    ) -> LoadMailboxResult {
-        let mut ret: LoadMailboxResult = LoadMailboxResult::Refresh;
-
         // TODO: Cleanup this function
         let folders = self.backend.folders();
         let folder = &folders[index];
@@ -133,50 +144,7 @@ impl Account {
             let id = self.sent_folder.unwrap();
             if id == index {
                 /* ======================== */
-                let old_m = mem::replace(
+                self.folders[index] = Some(Mailbox::new(folder, &None, envelopes));
-                    &mut self.folders[index],
-                    Some(Mailbox::new(folder, &None, envelopes)),
-                );
-                if let Some(old_m) = old_m {
-                    if self.folders[index].is_some() && old_m.is_ok() {
-                        let diff = self.folders[index]
-                            .as_ref()
-                            .map(|v| v.as_ref().unwrap().collection.len())
-                            .unwrap_or(0)
-                            .saturating_sub(
-                                old_m.as_ref().map(|v| v.collection.len()).unwrap_or(0),
-                            );
-                        if diff > 0 {
-                            let mut index = old_m
-                                .as_ref()
-                                .unwrap()
-                                .collection
-                                .iter()
-                                .zip(
-                                    &self.folders[index]
-                                        .as_ref()
-                                        .unwrap()
-                                        .as_ref()
-                                        .unwrap()
-                                        .collection,
-                                )
-                                .count();
-                            ret = LoadMailboxResult::New(NewMailEvent {
-                                folder: folder.hash(),
-                                index: (index.saturating_sub(1)
-                                    ..(self.folders[index]
-                                        .as_ref()
-                                        .unwrap()
-                                        .as_ref()
-                                        .unwrap()
-                                        .collection
-                                        .len()
-                                        .saturating_sub(1)))
-                                    .collect(),
-                            });
-                        }
-                    }
-                }
             /* ======================== */
             } else {
                 let (sent, cur) = {
@@ -194,97 +162,20 @@ impl Account {
                     sent[0] = Some(Mailbox::new(sent_path, &None, envelopes.clone()));
                 }
                 /* ======================== */
-                let old_m =
+                cur[0] = Some(Mailbox::new(folder, &sent[0], envelopes));
-                    mem::replace(&mut cur[0], Some(Mailbox::new(folder, &sent[0], envelopes)));
-                if let Some(old_m) = old_m {
-                    if cur[0].is_some() && old_m.is_ok() {
-                        let diff = cur[0]
-                            .as_ref()
-                            .map(|v| v.as_ref().unwrap().collection.len())
-                            .unwrap_or(0)
-                            .saturating_sub(
-                                old_m.as_ref().map(|v| v.collection.len()).unwrap_or(0),
-                            );
-                        if diff > 0 {
-                            let mut index = old_m
-                                .as_ref()
-                                .unwrap()
-                                .collection
-                                .iter()
-                                .zip(&cur[0].as_ref().unwrap().as_ref().unwrap().collection)
-                                .count();
-                            ret = LoadMailboxResult::New(NewMailEvent {
-                                folder: folder.hash(),
-                                index: (index.saturating_sub(1)
-                                    ..(cur[0]
-                                        .as_ref()
-                                        .unwrap()
-                                        .as_ref()
-                                        .unwrap()
-                                        .collection
-                                        .len())
-                                        .saturating_sub(1))
-                                    .collect(),
-                            });
-                        }
-                    }
-                }
                 /* ======================== */
             }
         } else {
             /* ======================== */
-            let old_m = mem::replace(
+            self.folders[index] = Some(Mailbox::new(folder, &None, envelopes));
-                &mut self.folders[index],
-                Some(Mailbox::new(folder, &None, envelopes)),
-            );
-            if let Some(old_m) = old_m {
-                if self.folders[index].is_some() && old_m.is_ok() {
-                    let diff = self.folders[index]
-                        .as_ref()
-                        .map(|v| v.as_ref().unwrap().collection.len())
-                        .unwrap_or(0)
-                        .saturating_sub(old_m.as_ref().map(|v| v.collection.len()).unwrap_or(0));
-                    if diff > 0 {
-                        let mut index = old_m
-                            .as_ref()
-                            .unwrap()
-                            .collection
-                            .iter()
-                            .zip(
-                                &self.folders[index]
-                                    .as_ref()
-                                    .unwrap()
-                                    .as_ref()
-                                    .unwrap()
-                                    .collection,
-                            )
-                            .count();
-                        ret = LoadMailboxResult::New(NewMailEvent {
-                            folder: folder.hash(),
-                            index: (index.saturating_sub(1)
-                                ..(self.folders[index]
-                                    .as_ref()
-                                    .unwrap()
-                                    .as_ref()
-                                    .unwrap()
-                                    .collection
-                                    .len()
-                                    .saturating_sub(1)))
-                                .collect(),
-                        });
-                    }
-                }
-            }
             /* ======================== */
         };
-
-        ret
     }
 
-    pub fn status(&mut self, index: usize) -> result::Result<LoadMailboxResult, usize> {
+    pub fn status(&mut self, index: usize) -> result::Result<(), usize> {
         match self.workers[index].as_mut() {
             None => {
-                return Ok(LoadMailboxResult::Loaded);
+                return Ok(());
             }
             Some(ref mut w) => match w.poll() {
                 Ok(AsyncStatus::NoUpdate) => {

ui/src/types/mod.rs

@@ -20,7 +20,7 @@
  */
 
 pub mod accounts;
-pub use self::accounts::{Account, LoadMailboxResult};
+pub use self::accounts::Account;
 #[macro_use]
 mod position;
 #[macro_use]
@@ -57,16 +57,14 @@ pub enum ThreadEvent {
     /// User input.
     Input(Key),
     /// A watched folder has been refreshed.
-    RefreshMailbox {
+    RefreshMailbox(RefreshEvent),
-        hash: u64,
-    },
     UIEvent(UIEventType),
     //Decode { _ }, // For gpg2 signature check
 }
 
 impl From<RefreshEvent> for ThreadEvent {
     fn from(event: RefreshEvent) -> Self {
-        ThreadEvent::RefreshMailbox { hash: event.hash() }
+        ThreadEvent::RefreshMailbox(event)
     }
 }
 
@@ -89,7 +87,7 @@ pub enum UIEventType {
     ChangeMailbox(usize),
     ChangeMode(UIMode),
     Command(String),
-    Notification(String),
+    Notification(Option<String>, String),
     Action(Action),
     StatusEvent(StatusEvent),
     MailboxUpdate((usize, usize)), // (account_idx, mailbox_idx)