mox!

imapserver/protocol.go

@@ -0,0 +1,186 @@
+package imapserver
+
+import (
+	"fmt"
+	"time"
+
+	"github.com/mjl-/mox/store"
+)
+
+type numSet struct {
+	searchResult bool // "$"
+	ranges       []numRange
+}
+
+// containsSeq returns whether seq is in the numSet, given uids and (saved) searchResult.
+// uids and searchResult must be sorted. searchResult can have uids that are no longer in uids.
+func (ss numSet) containsSeq(seq msgseq, uids []store.UID, searchResult []store.UID) bool {
+	if len(uids) == 0 {
+		return false
+	}
+	if ss.searchResult {
+		uid := uids[int(seq)-1]
+		return uidSearch(searchResult, uid) > 0 && uidSearch(uids, uid) > 0
+	}
+	for _, r := range ss.ranges {
+		first := r.first.number
+		if r.first.star {
+			first = 1
+		}
+		last := first
+		if r.last != nil {
+			last = r.last.number
+			if r.last.star {
+				last = uint32(len(uids))
+			}
+		}
+		if last > uint32(len(uids)) {
+			last = uint32(len(uids))
+		}
+		if uint32(seq) >= first && uint32(seq) <= last {
+			return true
+		}
+	}
+	return false
+}
+
+func (ss numSet) containsUID(uid store.UID, uids []store.UID, searchResult []store.UID) bool {
+	if len(uids) == 0 {
+		return false
+	}
+	if ss.searchResult {
+		return uidSearch(searchResult, uid) > 0 && uidSearch(uids, uid) > 0
+	}
+	for _, r := range ss.ranges {
+		first := store.UID(r.first.number)
+		if r.first.star {
+			first = uids[0]
+		}
+		last := first
+		// Num in <num>:* can be larger than last, but it still matches the last...
+		// Similar for *:<num>. ../rfc/9051:4814
+		if r.last != nil {
+			last = store.UID(r.last.number)
+			if r.last.star {
+				last = uids[len(uids)-1]
+				if last > first {
+					first = last
+				}
+			} else if r.first.star && last < first {
+				last = first
+			}
+		}
+		if uid < first || uid > last {
+			continue
+		}
+		if uidSearch(uids, uid) > 0 {
+			return true
+		}
+	}
+	return false
+}
+
+func (ss numSet) String() string {
+	if ss.searchResult {
+		return "$"
+	}
+	s := ""
+	for _, r := range ss.ranges {
+		if s != "" {
+			s += ","
+		}
+		if r.first.star {
+			s += "*"
+		} else {
+			s += fmt.Sprintf("%d", r.first.number)
+		}
+		if r.last == nil {
+			if r.first.star {
+				panic("invalid numSet range first star without last")
+			}
+			continue
+		}
+		s += ":"
+		if r.last.star {
+			s += "*"
+		} else {
+			s += fmt.Sprintf("%d", r.last.number)
+		}
+	}
+	return s
+}
+
+type setNumber struct {
+	number uint32
+	star   bool
+}
+
+type numRange struct {
+	first setNumber
+	last  *setNumber // if nil, this numRange is just a setNumber in "first" and first.star will be false
+}
+
+type partial struct {
+	offset uint32
+	count  uint32
+}
+
+type sectionPart struct {
+	part []uint32
+	text *sectionText
+}
+
+type sectionText struct {
+	mime    bool // if "MIME"
+	msgtext *sectionMsgtext
+}
+
+// a non-nil *sectionSpec with nil msgtext & nil part means there were []'s, but nothing inside. e.g. "BODY[]".
+type sectionSpec struct {
+	msgtext *sectionMsgtext
+	part    *sectionPart
+}
+
+type sectionMsgtext struct {
+	s       string   // "HEADER", "HEADER.FIELDS", "HEADER.FIELDS.NOT", "TEXT"
+	headers []string // for "HEADER.FIELDS"*
+}
+
+type fetchAtt struct {
+	field         string // uppercase, eg "ENVELOPE", "BODY". ".PEEK" is removed.
+	peek          bool
+	section       *sectionSpec
+	sectionBinary []uint32
+	partial       *partial
+}
+
+type searchKey struct {
+	// Only one of searchKeys, seqSet and op can be non-nil/non-empty.
+	searchKeys  []searchKey // In case of nested/multiple keys. Also for the top-level command.
+	seqSet      *numSet     // In case of bare sequence set. For op UID, field uidSet contains the parameter.
+	op          string      // Determines which of the fields below are set.
+	headerField string
+	astring     string
+	date        time.Time
+	atom        string
+	number      int64
+	searchKey   *searchKey
+	searchKey2  *searchKey
+	uidSet      numSet
+}
+
+func compactUIDSet(l []store.UID) (r numSet) {
+	for len(l) > 0 {
+		e := 1
+		for ; e < len(l) && l[e] == l[e-1]+1; e++ {
+		}
+		first := setNumber{number: uint32(l[0])}
+		var last *setNumber
+		if e > 1 {
+			last = &setNumber{number: uint32(l[e-1])}
+		}
+		r.ranges = append(r.ranges, numRange{first, last})
+		l = l[e:]
+	}
+	return
+}