1 files changed, 118 insertions, 0 deletions
diff --git a/ui/messages/parser/htmltagarray.go b/ui/messages/parser/htmltagarray.go
new file mode 100644
index 0000000..4cd4245
--- /dev/null
+++ b/ui/messages/parser/htmltagarray.go
@@ -0,0 +1,118 @@
+// gomuks - A terminal Matrix client written in Go.
+// Copyright (C) 2018 Tulir Asokan
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+package parser
+
+// TagWithMeta is an open HTML tag with some metadata (e.g. list index, a href value).
+type TagWithMeta struct {
+	Tag     string
+	Counter int
+	Meta    string
+	Text    string
+}
+
+// BlankTag is a blank TagWithMeta object.
+var BlankTag = &TagWithMeta{}
+
+// TagArray is a reversed queue for remembering what HTML tags are open.
+type TagArray []*TagWithMeta
+
+// Pushb converts the given byte array into a string and calls Push().
+func (ta *TagArray) Pushb(tag []byte) {
+	ta.Push(string(tag))
+}
+
+// Popb converts the given byte array into a string and calls Pop().
+func (ta *TagArray) Popb(tag []byte) *TagWithMeta {
+	return ta.Pop(string(tag))
+}
+
+// Indexb converts the given byte array into a string and calls Index().
+func (ta *TagArray) Indexb(tag []byte) {
+	ta.Index(string(tag))
+}
+
+// IndexAfterb converts the given byte array into a string and calls IndexAfter().
+func (ta *TagArray) IndexAfterb(tag []byte, after int) {
+	ta.IndexAfter(string(tag), after)
+}
+
+// Push adds the given tag to the array.
+func (ta *TagArray) Push(tag string) {
+	ta.PushMeta(&TagWithMeta{Tag: tag})
+}
+
+// Push adds the given tag to the array.
+func (ta *TagArray) PushMeta(tag *TagWithMeta) {
+	*ta = append(*ta, BlankTag)
+	copy((*ta)[1:], *ta)
+	(*ta)[0] = tag
+}
+
+// Pop removes the given tag from the array.
+func (ta *TagArray) Pop(tag string) (removed *TagWithMeta) {
+	if (*ta)[0].Tag == tag {
+		// This is the default case and is lighter than append(), so we handle it separately.
+		removed = (*ta)[0]
+		*ta = (*ta)[1:]
+	} else if index := ta.Index(tag); index != -1 {
+		removed = (*ta)[index]
+		*ta = append((*ta)[:index], (*ta)[index+1:]...)
+	}
+	return
+}
+
+// Index returns the first index where the given tag is, or -1 if it's not in the list.
+func (ta *TagArray) Index(tag string) int {
+	return ta.IndexAfter(tag, -1)
+}
+
+// IndexAfter returns the first index after the given index where the given tag is,
+// or -1 if the given tag is not on the list after the given index.
+func (ta *TagArray) IndexAfter(tag string, after int) int {
+	for i := after + 1; i < len(*ta); i++ {
+		if (*ta)[i].Tag == tag {
+			return i
+		}
+	}
+	return -1
+}
+
+// Get returns the first occurrence of the given tag, or nil if it's not in the list.
+func (ta *TagArray) Get(tag string) *TagWithMeta {
+	return ta.GetAfter(tag, -1)
+}
+
+// IndexAfter returns the first occurrence of the given tag, or nil if the given
+// tag is not on the list after the given index.
+func (ta *TagArray) GetAfter(tag string, after int) *TagWithMeta {
+	for i := after + 1; i < len(*ta); i++ {
+		if (*ta)[i].Tag == tag {
+			return (*ta)[i]
+		}
+	}
+	return nil
+}
+
+// Has returns whether or not the list has at least one of the given tags.
+func (ta *TagArray) Has(tags ...string) bool {
+	for _, tag := range tags {
+		if index := ta.Index(tag); index != -1 {
+			return true
+		}
+	}
+	return false
+}