Add allowed context matching

src/context.rs

@@ -1 +1,156 @@
-// Placeholder for upcoming context module.
+use crate::domain::AllowedContext;
+
+pub fn domain_allowed(context: &AllowedContext, candidate: &str) -> bool {
+    let candidate = normalize_domain(candidate);
+    if candidate.is_empty() {
+        return false;
+    }
+
+    context.domains.iter().any(|allowed| {
+        let allowed = normalize_domain(allowed);
+        !allowed.is_empty()
+            && (candidate == allowed
+                || candidate
+                    .strip_suffix(&allowed)
+                    .is_some_and(|prefix| prefix.ends_with('.')))
+    })
+}
+
+pub fn window_class_allowed(context: &AllowedContext, candidate: &str) -> bool {
+    let candidate = normalize_casefolded(candidate);
+    if candidate.is_empty() {
+        return false;
+    }
+
+    context
+        .window_classes
+        .iter()
+        .any(|allowed| normalize_casefolded(allowed) == candidate)
+}
+
+pub fn window_title_allowed(context: &AllowedContext, candidate: &str) -> bool {
+    let candidate = normalize_casefolded(candidate);
+    if candidate.is_empty() {
+        return false;
+    }
+
+    context.window_title_substrings.iter().any(|allowed| {
+        let allowed = normalize_casefolded(allowed);
+        !allowed.is_empty() && candidate.contains(&allowed)
+    })
+}
+
+pub fn command_allowed(context: &AllowedContext, candidate: &str) -> bool {
+    let candidate = executable_basename(candidate);
+    if candidate.is_empty() {
+        return false;
+    }
+
+    context
+        .commands
+        .iter()
+        .any(|allowed| executable_basename(allowed) == candidate)
+}
+
+fn normalize_domain(value: &str) -> String {
+    value.trim().trim_end_matches('.').to_lowercase()
+}
+
+fn normalize_casefolded(value: &str) -> String {
+    value.trim().to_lowercase()
+}
+
+fn executable_basename(command: &str) -> String {
+    let executable = command.split_whitespace().next().unwrap_or_default();
+    executable
+        .trim()
+        .rsplit(['/', '\\'])
+        .next()
+        .unwrap_or_default()
+        .to_lowercase()
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::domain::AllowedContext;
+
+    #[test]
+    fn domains_match_exact_or_subdomain() {
+        let context = AllowedContext {
+            domains: vec!["github.com".to_string()],
+            ..AllowedContext::default()
+        };
+
+        assert!(domain_allowed(&context, "github.com"));
+        assert!(domain_allowed(&context, "docs.github.com"));
+        assert!(!domain_allowed(&context, "evilgithub.com"));
+    }
+
+    #[test]
+    fn window_classes_match_case_insensitively_after_normalization() {
+        let context = AllowedContext {
+            window_classes: vec!["code".to_string()],
+            ..AllowedContext::default()
+        };
+
+        assert!(window_class_allowed(&context, "Code"));
+        assert!(!window_class_allowed(&context, "firefox"));
+    }
+
+    #[test]
+    fn titles_match_by_substring() {
+        let context = AllowedContext {
+            window_title_substrings: vec!["antidrift".to_string()],
+            ..AllowedContext::default()
+        };
+
+        assert!(window_title_allowed(&context, "Commitment OS - AntiDrift"));
+        assert!(!window_title_allowed(&context, "random video"));
+    }
+
+    #[test]
+    fn domains_ignore_whitespace_case_and_trailing_dots() {
+        let context = AllowedContext {
+            domains: vec![" GitHub.COM. ".to_string()],
+            ..AllowedContext::default()
+        };
+
+        assert!(domain_allowed(&context, " DOCS.GITHUB.COM. "));
+    }
+
+    #[test]
+    fn window_class_matching_trims_allowed_and_candidate_values() {
+        let context = AllowedContext {
+            window_classes: vec![" code ".to_string()],
+            ..AllowedContext::default()
+        };
+
+        assert!(window_class_allowed(&context, " Code "));
+    }
+
+    #[test]
+    fn title_matching_trims_allowed_substrings() {
+        let context = AllowedContext {
+            window_title_substrings: vec![" antidrift ".to_string()],
+            ..AllowedContext::default()
+        };
+
+        assert!(window_title_allowed(&context, "Commitment OS - AntiDrift"));
+    }
+
+    #[test]
+    fn commands_match_executable_basename() {
+        let context = AllowedContext {
+            commands: vec!["cargo".to_string()],
+            ..AllowedContext::default()
+        };
+
+        assert!(command_allowed(
+            &context,
+            "/home/felixm/.cargo/bin/cargo test"
+        ));
+        assert!(command_allowed(&context, "cargo"));
+        assert!(!command_allowed(&context, "/usr/bin/git status"));
+    }
+}