cache: implement the filtering

1 files changed, 103 insertions, 0 deletions

diff --git a/cache/filter.go b/cache/filter.go
new file mode 100644
index 00000000..91ab20c0
--- /dev/null
+++ b/cache/filter.go
@@ -0,0 +1,103 @@
+package cache
+
+import (
+	"strings"
+
+	"github.com/MichaelMure/git-bug/bug"
+)
+
+type Filter func(excerpt *BugExcerpt) bool
+
+func StatusFilter(query string) (Filter, error) {
+	status, err := bug.StatusFromString(query)
+	if err != nil {
+		return nil, err
+	}
+
+	return func(excerpt *BugExcerpt) bool {
+		return excerpt.Status == status
+	}, nil
+}
+
+func AuthorFilter(query string) Filter {
+	cleaned := strings.TrimFunc(query, func(r rune) bool {
+		return r == '"' || r == '\''
+	})
+
+	return func(excerpt *BugExcerpt) bool {
+		return excerpt.Author.Match(cleaned)
+	}
+}
+
+func LabelFilter(label string) Filter {
+	return func(excerpt *BugExcerpt) bool {
+		for _, l := range excerpt.Labels {
+			if string(l) == label {
+				return true
+			}
+		}
+		return false
+	}
+}
+
+func NoLabelFilter() Filter {
+	return func(excerpt *BugExcerpt) bool {
+		return len(excerpt.Labels) == 0
+	}
+}
+
+type Filters struct {
+	Status    []Filter
+	Author    []Filter
+	Label     []Filter
+	NoFilters []Filter
+}
+
+// Match check if a bug match the set of filters
+func (f *Filters) Match(excerpt *BugExcerpt) bool {
+	if match := f.orMatch(f.Status, excerpt); !match {
+		return false
+	}
+
+	if match := f.orMatch(f.Author, excerpt); !match {
+		return false
+	}
+
+	if match := f.orMatch(f.Label, excerpt); !match {
+		return false
+	}
+
+	if match := f.andMatch(f.NoFilters, excerpt); !match {
+		return false
+	}
+
+	return true
+}
+
+// Check if any of the filters provided match the bug
+func (*Filters) orMatch(filters []Filter, excerpt *BugExcerpt) bool {
+	if len(filters) == 0 {
+		return true
+	}
+
+	match := false
+	for _, f := range filters {
+		match = match || f(excerpt)
+	}
+
+	return match
+}
+
+// Check if all of the filters provided match the bug
+func (*Filters) andMatch(filters []Filter, excerpt *BugExcerpt) bool {
+	if len(filters) == 0 {
+		return true
+	}
+
+	match := true
+	for _, f := range filters {
+		match = match && f(excerpt)
+	}
+
+	return match
+}