init: pristine aerc 0.20.0 source

lib/sort/sort.go

@@ -0,0 +1,87 @@
+package sort
+
+import (
+	"errors"
+	"fmt"
+	"sort"
+	"strings"
+
+	"git.sr.ht/~rjarry/aerc/models"
+	"git.sr.ht/~rjarry/aerc/worker/types"
+)
+
+func GetSortCriteria(args []string) ([]*types.SortCriterion, error) {
+	var sortCriteria []*types.SortCriterion
+	reverse := false
+	for _, arg := range args {
+		if arg == "-r" {
+			reverse = true
+			continue
+		}
+		field, err := parseSortField(arg)
+		if err != nil {
+			return nil, err
+		}
+		sortCriteria = append(sortCriteria, &types.SortCriterion{
+			Field:   field,
+			Reverse: reverse,
+		})
+		reverse = false
+	}
+	if reverse {
+		return nil, errors.New("Expected argument to reverse")
+	}
+	return sortCriteria, nil
+}
+
+func parseSortField(arg string) (types.SortField, error) {
+	switch strings.ToLower(arg) {
+	case "arrival":
+		return types.SortArrival, nil
+	case "cc":
+		return types.SortCc, nil
+	case "date":
+		return types.SortDate, nil
+	case "from":
+		return types.SortFrom, nil
+	case "read":
+		return types.SortRead, nil
+	case "size":
+		return types.SortSize, nil
+	case "subject":
+		return types.SortSubject, nil
+	case "to":
+		return types.SortTo, nil
+	case "flagged":
+		return types.SortFlagged, nil
+	default:
+		return types.SortArrival, fmt.Errorf("%v is not a valid sort criterion", arg)
+	}
+}
+
+// Sorts toSort by sortBy so that toSort becomes a permutation following the
+// order of sortBy.
+// toSort should be a subset of sortBy
+func SortBy(toSort []models.UID, sortBy []models.UID) {
+	// build a map from sortBy
+	uidMap := make(map[models.UID]int)
+	for i, uid := range sortBy {
+		uidMap[uid] = i
+	}
+	// sortslice of toSort with less function of indexing the map sortBy
+	sort.Slice(toSort, func(i, j int) bool {
+		return uidMap[toSort[i]] < uidMap[toSort[j]]
+	})
+}
+
+// SortStringBy sorts the string slice s according to the order given in the
+// order string slice.
+func SortStringBy(s []string, order []string) {
+	m := make(map[string]int)
+	for i, d := range order {
+		m[d] = i
+	}
+	sort.Slice(s, func(i, j int) bool {
+		return m[s[i]] < m[s[j]]
+	})
+}