caldav: Outsource text-match to rustical_dav

crates/dav/Cargo.toml

@@ -28,3 +28,7 @@ headers.workspace = true
 strum.workspace = true
 matchit.workspace = true
 matchit-serde.workspace = true
+ical = { workspace = true, optional = true }
+
+[features]
+ical = ["dep:ical"]

crates/dav/src/xml/mod.rs

@@ -15,3 +15,7 @@ mod report_set;
 pub use report_set::SupportedReportSet;
 mod group;
 pub use group::*;
+#[cfg(feature = "ical")]
+mod text_match;
+#[cfg(feature = "ical")]
+pub use text_match::*;

crates/dav/src/xml/text_match.rs

@@ -0,0 +1,103 @@
+use ical::property::Property;
+use rustical_xml::{ValueDeserialize, XmlDeserialize};
+
+#[derive(Clone, Debug, PartialEq, Eq, Default)]
+pub enum TextCollation {
+    #[default]
+    AsciiCasemap,
+    Octet,
+}
+
+impl TextCollation {
+    // Check whether a haystack contains a needle respecting the collation
+    #[must_use]
+    pub fn match_text(&self, needle: &str, haystack: &str) -> bool {
+        match self {
+            // https://datatracker.ietf.org/doc/html/rfc4790#section-9.2
+            Self::AsciiCasemap => haystack
+                .to_ascii_uppercase()
+                .contains(&needle.to_ascii_uppercase()),
+            Self::Octet => haystack.contains(needle),
+        }
+    }
+}
+
+impl AsRef<str> for TextCollation {
+    fn as_ref(&self) -> &str {
+        match self {
+            Self::AsciiCasemap => "i;ascii-casemap",
+            Self::Octet => "i;octet",
+        }
+    }
+}
+
+impl ValueDeserialize for TextCollation {
+    fn deserialize(val: &str) -> Result<Self, rustical_xml::XmlError> {
+        match val {
+            "i;ascii-casemap" => Ok(Self::AsciiCasemap),
+            "i;octet" => Ok(Self::Octet),
+            _ => Err(rustical_xml::XmlError::InvalidVariant(format!(
+                "Invalid collation: {val}"
+            ))),
+        }
+    }
+}
+
+#[derive(Clone, Debug, PartialEq, Eq, Default)]
+pub struct NegateCondition(pub bool);
+
+impl ValueDeserialize for NegateCondition {
+    fn deserialize(val: &str) -> Result<Self, rustical_xml::XmlError> {
+        match val {
+            "yes" => Ok(Self(true)),
+            "no" => Ok(Self(false)),
+            _ => Err(rustical_xml::XmlError::InvalidVariant(format!(
+                "Invalid negate-condition parameter: {val}"
+            ))),
+        }
+    }
+}
+
+#[derive(XmlDeserialize, Clone, Debug, PartialEq, Eq)]
+#[allow(dead_code)]
+pub struct TextMatchElement {
+    #[xml(ty = "attr", default = "Default::default")]
+    pub collation: TextCollation,
+    #[xml(ty = "attr", default = "Default::default")]
+    pub negate_condition: NegateCondition,
+    #[xml(ty = "text")]
+    pub needle: String,
+}
+
+impl TextMatchElement {
+    #[must_use]
+    pub fn match_property(&self, property: &Property) -> bool {
+        let Self {
+            collation,
+            negate_condition,
+            needle,
+        } = self;
+
+        let matches = property
+            .value
+            .as_ref()
+            .is_some_and(|haystack| collation.match_text(needle, haystack));
+
+        // XOR
+        negate_condition.0 ^ matches
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::TextCollation;
+
+    #[test]
+    fn test_collation() {
+        assert!(TextCollation::AsciiCasemap.match_text("GrüN", "grün"));
+        assert!(!TextCollation::AsciiCasemap.match_text("GrÜN", "grün"));
+        assert!(!TextCollation::Octet.match_text("GrÜN", "grün"));
+        assert!(TextCollation::Octet.match_text("hallo", "hallo"));
+        assert!(TextCollation::AsciiCasemap.match_text("HaLlo", "hAllo"));
+    }
+}