git.r.bdr.sh - rbdr/olden-mail/blob - src/middleware/find_mailboxes_compatibility.rs

   1 use log::debug;
   2
   3 use super::Middleware;
   4
   5 /// `MailDrop` can't find folders to sync because it implements `IMAPv3` and
   6 /// sends FIND MAILBOXES /*, which does not exist in `IMAPv4`.
   7 /// which is not understood by modern servers. It instead replaces it with
   8 /// a LIST command.
   9 pub struct FindMailboxesCompatibility {
  10     tags: Vec<String>,
  11 }
  12
  13 impl FindMailboxesCompatibility {
  14     pub fn new() -> Self {
  15         FindMailboxesCompatibility { tags: vec![] }
  16     }
  17 }
  18
  19 impl Middleware for FindMailboxesCompatibility {
  20     fn client_message(&mut self, input: &[u8]) -> Vec<u8> {
  21         let command = String::from_utf8_lossy(input);
  22         if command.contains("FIND MAILBOXES /*") {
  23             if let Some(tag) = command.split("FIND MAILBOXES /*").next() {
  24                 // We'll need to convert the LIST to a FIND
  25                 self.tags.push(tag.trim().to_string());
  26                 let replacement = format!("{} LIST \"\" \"*\"\r\n", tag.trim());
  27                 let debug_str = replacement
  28                     .replace('\n', "\\n")
  29                     .replace('\r', "\\r")
  30                     .replace('\t', "\\t");
  31                 debug!("### {debug_str}");
  32                 return replacement.into_bytes();
  33             }
  34         }
  35         input.to_vec()
  36     }
  37
  38     fn server_message(&mut self, input: &[u8]) -> Vec<u8> {
  39         let command = String::from_utf8_lossy(input);
  40         let contains_ok_completed = self
  41             .tags
  42             .iter()
  43             .any(|tag| command.contains(&format!("{tag} OK Completed")));
  44
  45         // We want to only modify responses that were a result of a MAILBOX call.
  46         if !contains_ok_completed {
  47             return input.to_vec();
  48         }
  49
  50         let lines: Vec<String> = command
  51             .lines()
  52             .filter_map(|line| {
  53                 // The IMAPv3 spec specifically says INBOX is excluded from MAILBOX
  54                 if line.starts_with("* LIST") && line.trim_end().ends_with("\"/\" INBOX") {
  55                     return None;
  56                 }
  57
  58                 // Transform IMAPv4 "* LIST" lines to IMAPv3 "* MAILBOX"
  59                 if line.starts_with("* LIST") {
  60                     if let Some(last_slash_pos) = line.rfind('/') {
  61                         let mailbox_name = line[(last_slash_pos + 2)..].trim();
  62                         return Some(format!("* MAILBOX {mailbox_name}\r"));
  63                     }
  64                 }
  65
  66                 Some(line.to_string())
  67             })
  68             .collect();
  69
  70         let replacement = lines.join("\n");
  71         let debug_str = replacement
  72             .replace('\n', "\\n")
  73             .replace('\r', "\\r")
  74             .replace('\t', "\\t");
  75         debug!("### {debug_str}");
  76
  77         replacement.into_bytes()
  78     }
  79 }