1 files changed, 134 insertions, 0 deletions
diff --git a/src/timezone.rs b/src/timezone.rs
new file mode 100644
index 0000000..0d76e50
--- /dev/null
+++ b/src/timezone.rs
@@ -0,0 +1,134 @@
+use std::ops::Deref;
+use std::ffi::{CString,CStr};
+use crate::ical;
+
+use crate::utils::dateutil;
+use super::IcalTime;
+
+pub struct IcalTimeZone {
+  timezone: *mut ical::icaltimezone,
+}
+
+impl Deref for IcalTimeZone {
+  type Target = *mut ical::icaltimezone;
+
+  fn deref(&self) -> &*mut ical::icaltimezone {
+    &self.timezone
+  }
+}
+
+
+impl IcalTimeZone {
+  pub fn from_ptr_copy(ptr: *const ical::icaltimezone) -> Self {
+    let timezone = unsafe {
+      // unsafe, but we know icaltimezone_copy doesn't actually mutate
+      ical::icaltimezone_copy(ptr as *mut ical::icaltimezone)
+    };
+    IcalTimeZone{ timezone }
+  }
+
+  pub fn from_name(tz_name: &str) -> Result<Self,String> {
+    let tz_cstr = CString::new(tz_name).unwrap();
+    let builtin = unsafe { ical::icaltimezone_get_builtin_timezone(tz_cstr.as_ptr()) };
+    if !builtin.is_null() {
+      // need to copy here to guarantee we don't touch the builtin zones
+      let timezone = unsafe { ical::icaltimezone_copy(builtin) };
+      Ok(IcalTimeZone{ timezone })
+    } else {
+      Err(format!("Unknown timezone: {}", tz_name))
+    }
+  }
+
+  pub fn local() -> Self {
+    let tz_name = dateutil::find_local_timezone();
+    IcalTimeZone::from_name(&tz_name).unwrap()
+  }
+
+  pub fn utc() -> Self {
+    let timezone = unsafe { ical::icaltimezone_get_utc_timezone() };
+    IcalTimeZone{ timezone }
+  }
+
+  pub fn get_name(&self) -> String {
+    unsafe {
+      let name = ical::icaltimezone_get_display_name(self.timezone);
+      CStr::from_ptr(name).to_string_lossy().trim().to_string()
+    }
+  }
+
+  pub fn get_offset_at_time(&self, time: &IcalTime) -> i32 {
+    let mut icaltime = **time;
+    let mut is_dst = 0;
+    unsafe {
+      ical::icaltimezone_get_utc_offset(self.timezone, &mut icaltime , &mut is_dst)
+    }
+  }
+
+  pub fn ymd(&self, year: i32, month: i32, day: i32) -> IcalTime {
+    IcalTime::floating_ymd(year, month, day).with_timezone(&self)
+  }
+}
+
+#[cfg(test)]
+mod tests {
+  use super::*;
+
+  use crate::testdata;
+
+  #[test]
+  fn test_utc() {
+    let tz = IcalTimeZone::utc();
+    assert_eq!("UTC", tz.get_name());
+  }
+
+  #[test]
+  fn test_get_offset_utc() {
+    let tz = IcalTimeZone::utc();
+    let time = IcalTime::utc();
+
+    let offset = tz.get_offset_at_time(&time);
+
+    assert_eq!(0, offset);
+  }
+
+  #[test]
+  fn test_ymd() {
+    let tz = IcalTimeZone::from_name("US/Eastern").unwrap();
+    let date = tz.ymd(2014,3,1);
+    assert_eq!(IcalTime::floating_ymd(2014,3,1), date);
+    assert_eq!(1393650000, date.timestamp());
+    assert_eq!("US/Eastern", date.get_timezone().unwrap().get_name());
+  }
+
+  #[test]
+  fn test_ymd_and_hms() {
+    let tz = IcalTimeZone::from_name("US/Eastern").unwrap();
+    let date = tz.ymd(2014,3,1).and_hms(17, 20, 0);
+    assert_eq!(IcalTime::floating_ymd(2014,3,1).and_hms(17, 20, 0), date);
+    assert_eq!(1393712400, date.timestamp());
+    assert_eq!("US/Eastern", date.get_timezone().unwrap().get_name());
+  }
+
+  #[test]
+  fn test_from_name() {
+    let tz = IcalTimeZone::from_name("US/Eastern").unwrap();
+    assert_eq!("US/Eastern", tz.get_name());
+  }
+
+  #[test]
+  fn test_from_name_fail() {
+    let tz = IcalTimeZone::from_name("lulz");
+    assert!(tz.is_err());
+  }
+
+  #[test]
+  fn test_get_offset_eastern() {
+    let time = IcalTime::utc();
+    let tz = IcalTimeZone::from_name("US/Eastern").unwrap();
+
+    let offset = tz.get_offset_at_time(&time);
+
+    assert_eq!(-5*60*60, offset);
+  }
+
+}