Use iterators and itertools to produce events

6 files changed, 38 insertions, 36 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 00cfe7d..6335f17 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -13,6 +13,7 @@ dependencies = [
  "chrono 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "chrono-tz 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "ical 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "itertools 0.7.11 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -66,6 +67,11 @@ dependencies = [
 ]
 
 [[package]]
+name = "either"
+version = "1.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
 name = "error-chain"
 version = "0.10.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -82,6 +88,14 @@ dependencies = [
 ]
 
 [[package]]
+name = "itertools"
+version = "0.7.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "either 1.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "lazy_static"
 version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -212,8 +226,10 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum cfg-if 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)" = "082bb9b28e00d3c9d39cc03e64ce4cea0f1bb9b3fde493f0cbc008472d22bdf4"
 "checksum chrono 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)" = "45912881121cb26fad7c38c17ba7daa18764771836b34fab7d3fbd93ed633878"
 "checksum chrono-tz 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)" = "44420a821d3075c6b4dcdba557104274a240b5b6e323dc17136507e96ca2db59"
+"checksum either 1.5.0 (registry+https://github.com/rust-lang/crates.io-index)" = "3be565ca5c557d7f59e7cfcf1844f9e3033650c929c6566f511e8005f205c1d0"
 "checksum error-chain 0.10.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d9435d864e017c3c6afeac1654189b06cdb491cf2ff73dbf0d73b0f292f42ff8"
 "checksum ical 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)" = "a985f921bf84e6d00286f0f41363e2d39978370d8d8868c114002d863c27094f"
+"checksum itertools 0.7.11 (registry+https://github.com/rust-lang/crates.io-index)" = "0d47946d458e94a1b7bcabbf6521ea7c037062c81f534615abcad76e84d4970d"
 "checksum lazy_static 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "a374c89b9db55895453a74c1e38861d9deec0b01b405a82516e9d5de4820dea1"
 "checksum libc 0.2.44 (registry+https://github.com/rust-lang/crates.io-index)" = "10923947f84a519a45c8fefb7dd1b3e8c08747993381adee176d7a82b4195311"
 "checksum memchr 2.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "0a3eb002f0535929f1199681417029ebea04aadc0c7a4224b46be99c7f5d6a16"
diff --git a/Cargo.toml b/Cargo.toml
index 5bae8e6..6f5bdb3 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -6,6 +6,7 @@ authors = ["meskio <meskio@sindominio.net>"]
 [dependencies]
 chrono = "0.4"
 chrono-tz = "0.5"
+itertools = "0.7"
 
 [dependencies.ical]
 version = "0.5.*"
diff --git a/src/calendar.rs b/src/calendar.rs
index 6df2f74..fcec54e 100644
--- a/src/calendar.rs
+++ b/src/calendar.rs
@@ -2,9 +2,9 @@ use std::io::BufRead;
 use std::fmt;
 use ical::IcalParser;
 use chrono::Duration;
+use itertools::Itertools;
 
 use date::Date;
-use event;
 use event::{Event, End};
 use periodic::Periodic;
 use errors::EventError;
@@ -62,17 +62,13 @@ impl Calendar {
         Ok(Calendar { single, periodic })
     }
 
-    pub fn get(&self, first: &Date, last: &Date) -> Vec<Event> {
-        let mut events = event::get(&self.single, first, last).to_vec();
-        for p in &self.periodic {
-            let mut p_events = p.iter()
-                .skip_while(|e| e.end_date() < *first)
-                .take_while(|e| e.start <= *last)
-                .collect();
-            events.append(&mut p_events);
-        }
-        events.sort();
-        events
+    pub fn iter<'a>(&'a self) -> impl Iterator<Item = Event> + 'a {
+        self.single.iter().map(Event::clone).merge(
+            self.periodic
+                .iter()
+                .map(|p| p.iter())
+                .kmerge(),
+        )
     }
 }
 
diff --git a/src/event.rs b/src/event.rs
index b5e9d27..e186cfd 100644
--- a/src/event.rs
+++ b/src/event.rs
@@ -94,17 +94,3 @@ impl FromStr for Status {
         }
     }
 }
-
-
-pub fn get<'a>(events: &'a Vec<Event>, first: &Date, last: &Date) -> &'a [Event] {
-    match events.iter().position(|ref e| e.start >= *first) {
-        None => &[],
-        Some(i) => {
-            let j = events
-                .iter()
-                .position(|ref e| e.end_date() > *last)
-                .unwrap_or(events.len());
-            &events[i..j]
-        }
-    }
-}
diff --git a/src/lib.rs b/src/lib.rs
index e754a11..b82b190 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,6 +1,7 @@
 extern crate ical;
 extern crate chrono;
 extern crate chrono_tz;
+extern crate itertools;
 
 mod date;
 mod event;
diff --git a/src/main.rs b/src/main.rs
index ce2284d..d531687 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,32 +1,34 @@
 extern crate almanac;
+extern crate itertools;
 
 use std::env;
 use std::io::BufReader;
 use std::fs::File;
+use itertools::Itertools;
 
 use almanac::Calendar;
 use almanac::Date;
 use almanac::Duration;
-use almanac::Event;
 
 fn main() {
     let first = Date::now();
     let last = first + Duration::days(7);
 
-    let mut events: Vec<_> = env::args()
-        .skip(1)
-        .map(|arg| ics_calendar(&arg, &first, &last))
-        .flatten()
-        .collect();
-    events.sort();
+    let calendars: Vec<_> = env::args().skip(1).map(|arg| ics_calendar(&arg)).collect();
+    let events = calendars
+        .iter()
+        .map(|c| c.iter())
+        .kmerge()
+        .skip_while(|e| e.end_date() < first)
+        .take_while(|e| e.start <= last);
+
     for event in events {
         println!("{}", event);
     }
 }
 
-fn ics_calendar(file_path: &str, first: &Date, last: &Date) -> Vec<Event> {
+fn ics_calendar(file_path: &str) -> Calendar {
     let file = File::open(file_path).unwrap();
     let buf = BufReader::new(file);
-    let calendar = Calendar::parse(buf).unwrap();
-    calendar.get(first, last)
+    Calendar::parse(buf).unwrap()
 }