Implement rrule parsing

Cargo.lock

@@ -2,6 +2,15 @@
 # It is not intended for manual editing.
 version = 3
 
+[[package]]
+name = "aho-corasick"
+version = "1.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b2969dcb958b36655471fc61f7e416fa76033bdd4bfed0678d8fee1e2d07a1f0"
+dependencies = [
+ "memchr",
+]
+
 [[package]]
 name = "android-tzdata"
 version = "0.1.1"
@@ -480,6 +489,7 @@ dependencies = [
  "chrono",
  "icalendar",
  "reqwest",
+ "rrule",
  "serde",
  "tokio",
  "urlencoding",
@@ -937,6 +947,8 @@ version = "1.8.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d0ab3ca65655bb1e41f2a8c8cd662eb4fb035e67c3f78da1d61dffe89d07300f"
 dependencies = [
+ "aho-corasick",
+ "memchr",
  "regex-syntax",
 ]
 
@@ -983,6 +995,20 @@ dependencies = [
  "winreg",
 ]
 
+[[package]]
+name = "rrule"
+version = "0.11.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "615777991e415d96aa97f6e45e809111911497c029e5d0df7f6d751d218d28e8"
+dependencies = [
+ "chrono",
+ "chrono-tz",
+ "lazy_static",
+ "log",
+ "regex",
+ "thiserror",
+]
+
 [[package]]
 name = "rustix"
 version = "0.37.20"

Cargo.toml

@@ -14,3 +14,4 @@ icalendar = { version = "0.15", features = ["chrono-tz"] }
 serde = { version = "1.0", features = ["derive"] }
 urlencoding = "2"
 chrono = "0"
+rrule = "0"

src/main.rs

@@ -80,10 +80,33 @@ async fn convert(urls: &[&str], days: Option<&String>) -> Result<CustomCalendar>
                     None => start + chrono::Duration::days(1),
                 };
 
-                if start < filter_start || start > filter_end {
+                let length = end - start;
+
+                let start_dates = if let Some(rrule) = event.properties().get("RRULE") {
+                    //let vector = Vec::new();
+                    let rrule_str = rrule.value();
+                    let string = format!("DTSTART:{}\n{}", event.properties().get("DTSTART").unwrap().value(), rrule_str);
+                    let rrule: rrule::RRuleSet = string.parse()?;
+                    let date_set = rrule.all(100).dates;
+                    date_set.iter().map(|x| x.with_timezone(&chrono::Utc)).collect()
+                } else {
+                    vec!(start)
+                };
+
+                let mut found = false;
+                for start_date in start_dates {
+                    if start_date >= filter_start && start_date <= filter_end {
+                        found = true;
+                        break;
+                    }
+                }
+
+                if !found {
                     continue;
                 }
 
+                let end = start + length;
+
                 entries.push(CustomCalendarEntry {
                     title: event.get_summary().unwrap_or("").to_string(),
                     description: event.get_description().unwrap_or("").to_string(),