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Diffstat (limited to 'src/imap/index.rs')
| -rw-r--r-- | src/imap/index.rs | 211 |
1 files changed, 0 insertions, 211 deletions
diff --git a/src/imap/index.rs b/src/imap/index.rs deleted file mode 100644 index 9b794b8..0000000 --- a/src/imap/index.rs +++ /dev/null @@ -1,211 +0,0 @@ -use std::num::{NonZeroU32, NonZeroU64}; - -use anyhow::{anyhow, Result}; -use imap_codec::imap_types::sequence::{SeqOrUid, Sequence, SequenceSet}; - -use crate::mail::uidindex::{ImapUid, ModSeq, UidIndex}; -use crate::mail::unique_ident::UniqueIdent; - -pub struct Index<'a> { - pub imap_index: Vec<MailIndex<'a>>, - pub internal: &'a UidIndex, -} -impl<'a> Index<'a> { - pub fn new(internal: &'a UidIndex) -> Result<Self> { - let imap_index = internal - .idx_by_uid - .iter() - .enumerate() - .map(|(i_enum, (&uid, &uuid))| { - let (_, modseq, flags) = internal - .table - .get(&uuid) - .ok_or(anyhow!("mail is missing from index"))?; - let i_int: u32 = (i_enum + 1).try_into()?; - let i: NonZeroU32 = i_int.try_into()?; - - Ok(MailIndex { - i, - uid, - uuid, - modseq: *modseq, - flags, - }) - }) - .collect::<Result<Vec<_>>>()?; - - Ok(Self { - imap_index, - internal, - }) - } - - pub fn last(&'a self) -> Option<&'a MailIndex<'a>> { - self.imap_index.last() - } - - /// Fetch mail descriptors based on a sequence of UID - /// - /// Complexity analysis: - /// - Sort is O(n * log n) where n is the number of uid generated by the sequence - /// - Finding the starting point in the index O(log m) where m is the size of the mailbox - /// While n =< m, it's not clear if the difference is big or not. - /// - /// For now, the algorithm tries to be fast for small values of n, - /// as it is what is expected by clients. - /// - /// So we assume for our implementation that : n << m. - /// It's not true for full mailbox searches for example... - pub fn fetch_on_uid(&'a self, sequence_set: &SequenceSet) -> Vec<&'a MailIndex<'a>> { - if self.imap_index.is_empty() { - return vec![]; - } - let largest = self.last().expect("The mailbox is not empty").uid; - let mut unroll_seq = sequence_set.iter(largest).collect::<Vec<_>>(); - unroll_seq.sort(); - - let start_seq = match unroll_seq.iter().next() { - Some(elem) => elem, - None => return vec![], - }; - - // Quickly jump to the right point in the mailbox vector O(log m) instead - // of iterating one by one O(m). Works only because both unroll_seq & imap_index are sorted per uid. - let mut imap_idx = { - let start_idx = self - .imap_index - .partition_point(|mail_idx| &mail_idx.uid < start_seq); - &self.imap_index[start_idx..] - }; - - let mut acc = vec![]; - for wanted_uid in unroll_seq.iter() { - // Slide the window forward as long as its first element is lower than our wanted uid. - let start_idx = match imap_idx.iter().position(|midx| &midx.uid >= wanted_uid) { - Some(v) => v, - None => break, - }; - imap_idx = &imap_idx[start_idx..]; - - // If the beginning of our new window is the uid we want, we collect it - if &imap_idx[0].uid == wanted_uid { - acc.push(&imap_idx[0]); - } - } - - acc - } - - pub fn fetch_on_id(&'a self, sequence_set: &SequenceSet) -> Result<Vec<&'a MailIndex<'a>>> { - if self.imap_index.is_empty() { - return Ok(vec![]); - } - let largest = NonZeroU32::try_from(self.imap_index.len() as u32)?; - let mut acc = sequence_set - .iter(largest) - .map(|wanted_id| { - self.imap_index - .get((wanted_id.get() as usize) - 1) - .ok_or(anyhow!("Mail not found")) - }) - .collect::<Result<Vec<_>>>()?; - - // Sort the result to be consistent with UID - acc.sort_by(|a, b| a.i.cmp(&b.i)); - - Ok(acc) - } - - pub fn fetch( - self: &'a Index<'a>, - sequence_set: &SequenceSet, - by_uid: bool, - ) -> Result<Vec<&'a MailIndex<'a>>> { - match by_uid { - true => Ok(self.fetch_on_uid(sequence_set)), - _ => self.fetch_on_id(sequence_set), - } - } - - pub fn fetch_changed_since( - self: &'a Index<'a>, - sequence_set: &SequenceSet, - maybe_modseq: Option<NonZeroU64>, - by_uid: bool, - ) -> Result<Vec<&'a MailIndex<'a>>> { - let raw = self.fetch(sequence_set, by_uid)?; - let res = match maybe_modseq { - Some(pit) => raw.into_iter().filter(|midx| midx.modseq > pit).collect(), - None => raw, - }; - - Ok(res) - } - - pub fn fetch_unchanged_since( - self: &'a Index<'a>, - sequence_set: &SequenceSet, - maybe_modseq: Option<NonZeroU64>, - by_uid: bool, - ) -> Result<(Vec<&'a MailIndex<'a>>, Vec<&'a MailIndex<'a>>)> { - let raw = self.fetch(sequence_set, by_uid)?; - let res = match maybe_modseq { - Some(pit) => raw.into_iter().partition(|midx| midx.modseq <= pit), - None => (raw, vec![]), - }; - - Ok(res) - } -} - -#[derive(Clone, Debug)] -pub struct MailIndex<'a> { - pub i: NonZeroU32, - pub uid: ImapUid, - pub uuid: UniqueIdent, - pub modseq: ModSeq, - pub flags: &'a Vec<String>, -} - -impl<'a> MailIndex<'a> { - // The following functions are used to implement the SEARCH command - pub fn is_in_sequence_i(&self, seq: &Sequence) -> bool { - match seq { - Sequence::Single(SeqOrUid::Asterisk) => true, - Sequence::Single(SeqOrUid::Value(target)) => target == &self.i, - Sequence::Range(SeqOrUid::Asterisk, SeqOrUid::Value(x)) - | Sequence::Range(SeqOrUid::Value(x), SeqOrUid::Asterisk) => x <= &self.i, - Sequence::Range(SeqOrUid::Value(x1), SeqOrUid::Value(x2)) => { - if x1 < x2 { - x1 <= &self.i && &self.i <= x2 - } else { - x1 >= &self.i && &self.i >= x2 - } - } - Sequence::Range(SeqOrUid::Asterisk, SeqOrUid::Asterisk) => true, - } - } - - pub fn is_in_sequence_uid(&self, seq: &Sequence) -> bool { - match seq { - Sequence::Single(SeqOrUid::Asterisk) => true, - Sequence::Single(SeqOrUid::Value(target)) => target == &self.uid, - Sequence::Range(SeqOrUid::Asterisk, SeqOrUid::Value(x)) - | Sequence::Range(SeqOrUid::Value(x), SeqOrUid::Asterisk) => x <= &self.uid, - Sequence::Range(SeqOrUid::Value(x1), SeqOrUid::Value(x2)) => { - if x1 < x2 { - x1 <= &self.uid && &self.uid <= x2 - } else { - x1 >= &self.uid && &self.uid >= x2 - } - } - Sequence::Range(SeqOrUid::Asterisk, SeqOrUid::Asterisk) => true, - } - } - - pub fn is_flag_set(&self, flag: &str) -> bool { - self.flags - .iter() - .any(|candidate| candidate.as_str() == flag) - } -} |