1 files changed, 47 insertions, 0 deletions
diff --git a/internals/src/mail_type.rs b/internals/src/mail_type.rs
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+++ b/internals/src/mail_type.rs
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+/// Specifies what kind of mail we want to create.
+#[derive(Debug, Clone, Copy, Hash, Eq, PartialEq)]
+pub enum MailType {
+    /// A 7-bit us-ascii mail.
+    Ascii,
+
+    /// A us-ascii mail, but the body can contain 8bit values.
+    ///
+    /// This for example allows sending a mail with an utf-8
+    /// formatted body. But be aware that aspects like line
+    /// length limit still count an the ascii bytes for "\r\n"
+    /// still count as newlines. So using this for any non-us-ascii
+    /// compatible encoding (e.g. utf-16) isn't a good idea.
+    /// Neither is it suited for directly containing resources
+    /// like images.
+    Mime8BitEnabled,
+
+    /// A internationalized mail.
+    ///
+    /// Internationalized mails extend multiple grammar parts
+    /// to allow any non us-ascii utf-8 code point additionally
+    /// to the already allowed utf-8 code points. Internationalized
+    /// mails are required for any mail containing a mailbox with
+    /// an non us-ascii local/user part (the part before the `@`).
+    /// They also strongly simplify non ascii utf-8 in all other
+    /// places like e.g. the `Subject` header.
+    Internationalized
+}
+
+impl MailType {
+
+    /// Returns true if the self is equal to `Internationalized`
+    #[inline]
+    pub fn is_internationalized(&self) -> bool {
+        *self == MailType::Internationalized
+    }
+
+    /// Returns true if self is either `Internationalized` or `Mime8BitEnabled`
+    pub fn supports_8bit_bodies( &self ) -> bool {
+        use self::MailType::*;
+        match *self {
+            Ascii => false,
+            Mime8BitEnabled => true,
+            Internationalized => true
+        }
+    }
+}