Add filtering for past events

Signed-off-by: Matthias Beyer <mail@beyermatthias.de>

4 files changed, 104 insertions, 3 deletions

diff --git a/bin/domain/imag-calendar/Cargo.toml b/bin/domain/imag-calendar/Cargo.toml
index 7801ac80..187468f3 100644
--- a/bin/domain/imag-calendar/Cargo.toml
+++ b/bin/domain/imag-calendar/Cargo.toml
@@ -26,6 +26,7 @@ failure    = "0.1"
 walkdir    = "2.2.8"
 vobject    = "0.7"
 handlebars = "2"
+chrono     = "0.4"
 
 libimagrt          = { version = "0.10.0", path = "../../../lib/core/libimagrt" }
 libimagstore       = { version = "0.10.0", path = "../../../lib/core/libimagstore" }
diff --git a/bin/domain/imag-calendar/src/filters.rs b/bin/domain/imag-calendar/src/filters.rs
new file mode 100644
index 00000000..aab19590
--- /dev/null
+++ b/bin/domain/imag-calendar/src/filters.rs
@@ -0,0 +1,86 @@
+//
+// imag - the personal information management suite for the commandline
+// Copyright (C) 2015-2019 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 chrono::NaiveDateTime;
+use failure::Fallible as Result;
+use vobject::icalendar::Event;
+
+/// Generate a filter function to filter shown events
+///
+/// If `do_filter` is false, this filter returns true all the time.
+///
+/// If an event is in the past, relative to the `today` parameter, the function returns false,
+/// else it returns true.
+///
+/// # Details
+///
+/// The date of the event is determined by using the "dtend" or "dtstamp" members of the event
+/// object. These fields are parsed to NaiveDateTime objects and then compared to the `today` object.
+///
+/// If an parsing error happens in the "dtend" parsing step, "dtstamp" is used. If this results also
+/// in a parsing error, the first error is returned.
+///
+pub fn filter_past(do_filter: bool, today: NaiveDateTime) -> impl FnOnce(&Event) -> Result<bool> {
+    move |pe| if do_filter {
+        let uid = || pe.uid()
+            .map(|uid| uid.into_raw())
+            .unwrap_or_else(|| String::from("<No UID>"));
+
+        let dtend_is_pre_today : Result<bool> = pe.dtend()
+            .map(|dtend| Ok(try_to_parse_datetime(dtend.raw())? < today))
+            .unwrap_or_else(|| Err({
+                format_err!("Entry with UID {} has no end time, cannot determine whether to list it",
+                            uid())
+            }));
+
+        let dtstamp_is_pre_today : Result<bool> = pe.dtstamp()
+            .map(|dtstamp| Ok(try_to_parse_datetime(dtstamp.raw())? < today))
+            .unwrap_or_else(|| Err({
+                format_err!("Entry with UID {} has no timestamp, cannot determine whether to list it",
+                            uid())
+            }));
+
+        trace!("dtend_is_pre_today   = {:?}", dtend_is_pre_today);
+        trace!("dtstamp_is_pre_today = {:?}", dtstamp_is_pre_today);
+
+        match (dtend_is_pre_today, dtstamp_is_pre_today) {
+            (Ok(b), _)  => return Ok(!b),
+            (_, Ok(b))  => return Ok(!b),
+            (Err(e), _) => return Err(e)
+        }
+    } else {
+        Ok(true)
+    }
+}
+
+fn try_to_parse_datetime(s: &str) -> Result<NaiveDateTime> {
+    const FORMATS : &[&'static str] = &[
+        "%Y%m%dT%H%M%S",
+        "%Y%m%dT%H%M%SZ"
+    ];
+
+    for format in FORMATS {
+        if let Ok(parsed) = NaiveDateTime::parse_from_str(s, format) {
+            return Ok(parsed);
+        }
+    }
+
+    Err(format_err!("Cannot parse datetime: {}", s))
+}
+
diff --git a/bin/domain/imag-calendar/src/main.rs b/bin/domain/imag-calendar/src/main.rs
index a94e2ee2..379374df 100644
--- a/bin/domain/imag-calendar/src/main.rs
+++ b/bin/domain/imag-calendar/src/main.rs
@@ -40,6 +40,7 @@ extern crate clap;
 extern crate toml_query;
 extern crate walkdir;
 extern crate handlebars;
+extern crate chrono;
 
 #[macro_use] extern crate libimagrt;
 extern crate libimagcalendar;
@@ -58,6 +59,7 @@ use toml_query::read::Partial;
 use toml_query::read::TomlValueReadExt;
 use walkdir::DirEntry;
 use walkdir::WalkDir;
+use vobject::icalendar::Event;
 
 use libimagcalendar::store::EventStore;
 use libimagerror::io::ToExitCode;
@@ -67,6 +69,7 @@ use libimagerror::trace::MapErrTrace;
 use libimagrt::runtime::Runtime;
 use libimagrt::setup::generate_runtime_setup;
 
+mod filters;
 mod ui;
 mod util;
 
@@ -168,6 +171,8 @@ fn list(rt: &Runtime) {
     let list_format = get_event_print_format("calendar.list_format", rt, &scmd)
         .map_err_trace_exit_unwrap();
 
+    let do_filter_past = !scmd.is_present("list-past");
+
     let ref_config      = rt.config()
         .ok_or_else(|| format_err!("No configuration, cannot continue!"))
         .map_err_trace_exit_unwrap()
@@ -181,7 +186,11 @@ fn list(rt: &Runtime) {
     debug!("List format: {:?}", list_format);
     debug!("Ref config : {:?}", ref_config);
 
-    let event_filter = |pefle: &ParsedEventFLE| true; // TODO: impl filtering
+    let event_filter = |e: &'_ Event| { // what a crazy hack to make the compiler happy
+        debug!("Filtering event: {:?}", e);
+        let f = filters::filter_past(do_filter_past, chrono::Local::now().naive_local());
+        f(e)
+    };
 
     let mut listed_events = 0;
 
@@ -195,7 +204,6 @@ fn list(rt: &Runtime) {
         .trace_unwrap_exit()
         .map(|ev| ParsedEventFLE::parse(ev, &ref_config))
         .trace_unwrap_exit()
-        .filter(|e| event_filter(e))
         .for_each(|parsed_entry| {
             parsed_entry
                 .get_data()
@@ -223,4 +231,3 @@ fn is_not_hidden(entry: &DirEntry) -> bool {
     !entry.file_name().to_str().map(|s| s.starts_with(".")).unwrap_or(false)
 }
 
-
diff --git a/bin/domain/imag-calendar/src/ui.rs b/bin/domain/imag-calendar/src/ui.rs
index 8386357e..9792ea9b 100644
--- a/bin/domain/imag-calendar/src/ui.rs
+++ b/bin/domain/imag-calendar/src/ui.rs
@@ -67,6 +67,13 @@ pub fn build_ui<'a>(app: App<'a, 'a>) -> App<'a, 'a> {
                         .required(false)
                         .multiple(false)
                         .help("Override the format used to list one event"))
+
+                   .arg(Arg::with_name("list-past")
+                        .long("past")
+                        .takes_value(false)
+                        .required(false)
+                        .multiple(false)
+                        .help("List past events"))
                    )
 }