imag/lib/entry/libimagentryannotation/src/annotation_fetcher.rs

117 lines
4 KiB
Rust

//
// imag - the personal information management suite for the commandline
// Copyright (C) 2015, 2016 Matthias Beyer <mail@beyermatthias.de> and contributors
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; version
// 2.1 of the License.
//
// This library 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
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
//
use libimagstore::store::Entry;
use libimagstore::store::Store;
use libimagentrylink::internal::InternalLinker;
use libimagnotes::notestore::NoteStore;
use libimagnotes::iter::NoteIterator;
use libimagstore::storeid::StoreIdIterator;
use error::Result;
use error::AnnotationErrorKind as AEK;
use error::ResultExt;
use self::iter::*;
pub trait AnnotationFetcher<'a> {
fn all_annotations(&'a self) -> Result<AnnotationIter<'a>>;
fn annotations_for_entry(&'a self, entry: &Entry) -> Result<AnnotationIter<'a>>;
}
impl<'a> AnnotationFetcher<'a> for Store {
/// Wrapper around `Note::all_notes()` of `libimagnotes` which filters out normal notes and
/// leaves only annotations in the iterator.
fn all_annotations(&'a self) -> Result<AnnotationIter<'a>> {
NoteStore::all_notes(self)
.map(|iter| AnnotationIter::new(iter, self))
.chain_err(|| AEK::StoreReadError)
}
/// Get all annotations (in an iterator) for an entry
///
/// Internally, this fetches the links of the entry, fetches all the entries behind the links
/// and filters them for annotations.
///
/// This might result in some heavy IO operations if a lot of stuff is linked to a single
/// entry, but should normally be not that heavy.
fn annotations_for_entry(&'a self, entry: &Entry) -> Result<AnnotationIter<'a>> {
entry.get_internal_links()
.chain_err(|| AEK::StoreReadError)
.map(|iter| StoreIdIterator::new(Box::new(iter.map(|e| e.get_store_id().clone()))))
.map(NoteIterator::new)
.map(|i| AnnotationIter::new(i, self))
}
}
pub mod iter {
use toml::Value;
use toml_query::read::TomlValueReadExt;
use libimagnotes::iter::NoteIterator;
use libimagstore::store::Store;
use libimagstore::store::FileLockEntry;
use error::Result;
use error::AnnotationErrorKind as AEK;
use error::AnnotationError as AE;
use error::ResultExt;
#[derive(Debug)]
pub struct AnnotationIter<'a>(NoteIterator, &'a Store);
impl<'a> AnnotationIter<'a> {
pub fn new(noteiter: NoteIterator, store: &'a Store) -> AnnotationIter<'a> {
AnnotationIter(noteiter, store)
}
}
impl<'a> Iterator for AnnotationIter<'a> {
type Item = Result<FileLockEntry<'a>>;
fn next(&mut self) -> Option<Self::Item> {
loop {
match self.0.next().map(|id| self.1.get(id)) {
Some(Ok(Some(note))) => {
match note.get_header().read("annotation.is_annotation") {
Ok(None) => continue, // not an annotation
Ok(Some(&Value::Boolean(true))) => return Some(Ok(note)),
Ok(Some(_)) => return Some(Err(AE::from_kind(AEK::HeaderTypeError))),
Err(e) => return Some(Err(e).chain_err(|| AEK::HeaderReadError)),
}
},
Some(Ok(None)) => continue,
Some(Err(e)) => return Some(Err(e).chain_err(|| AEK::StoreReadError)),
None => return None, // iterator consumed
}
}
}
}
}