arbitrary text support

thespine.go

@@ -2,19 +2,28 @@ package thespine
 
 import (
 	"errors"
+	"strings"
 	"unicode/utf8"
 )
 
+// THE_SIZE represents the size of grouping used by the anagram encode/decode
 const THE_SIZE = 3
 
+// ErrInvalidString represents an error for invalid UTF-8 string
 var ErrInvalidString = errors.New("invalid string")
 
+// Decode takes a UTF-8 string as an input and decodes the anagram.
+// Error returned in case of an invalid UTF-8 string.
 func Decode(s string) (string, error) {
 	if !utf8.ValidString(s) {
 		return "", ErrInvalidString
 	}
 	sr := []rune(s)
 	l := len(sr)
+	if l <= THE_SIZE {
+		return s, nil
+	}
+
 	g := make([][]rune, 0)
 	gc := l / THE_SIZE
 	if l%THE_SIZE != 0 {
@@ -29,15 +38,21 @@ func Decode(s string) (string, error) {
 		gs := sr[si:ei]
 		g = append(g, gs)
 	}
-	return concat(g), nil
+	return runestring(g), nil
 }
 
+// Encode takes a UTF-8 string as an input and generates an anagram out of it.
+// Error returned in case of an invalid UTF-8 string.
 func Encode(s string) (string, error) {
 	if !utf8.ValidString(s) {
 		return "", ErrInvalidString
 	}
 	sr := []rune(s)
 	l := len(sr)
+	if l <= THE_SIZE {
+		return s, nil
+	}
+
 	g := make([][]rune, 0)
 	gc := l / THE_SIZE
 	if l%THE_SIZE != 0 {
@@ -55,10 +70,46 @@ func Encode(s string) (string, error) {
 	for i, j := 0, len(g)-1; i < j; i, j = i+1, j-1 {
 		g[i], g[j] = g[j], g[i]
 	}
-	return concat(g), nil
+	return runestring(g), nil
+}
+
+// EncodeText takes a UTF-8 string as an input, splits it by whitespace and runs an anagram for each word.
+// Error returned in case of an invalid UTF-8 string.
+func EncodeText(s string) (string, error) {
+	o := ""
+	ws := strings.Split(s, " ")
+	for i, w := range ws {
+		ew, err := Encode(w)
+		if err != nil {
+			return "", err
+		}
+		o += ew
+		if i != len(ws)-1 {
+			o += " "
+		}
+	}
+	return o, nil
+}
+
+// DecodeText takes a UTF-8 string as an input, splits it by whitespace and decodes each anagram word-by-word.
+// Error returned in case of an invalid UTF-8 string.
+func DecodeText(s string) (string, error) {
+	o := ""
+	ws := strings.Split(s, " ")
+	for i, w := range ws {
+		ew, err := Decode(w)
+		if err != nil {
+			return "", err
+		}
+		o += ew
+		if i < len(ws)-1 {
+			o += " "
+		}
+	}
+	return o, nil
 }
 
-func concat(r [][]rune) string {
+func runestring(r [][]rune) string {
 	var s string
 	for _, r := range r {
 		s += string(r)

thespine_test.go

@@ -61,7 +61,7 @@ func Test_Decode(t *testing.T) {
 				t.Fatalf("decode err wanted but got none")
 			}
 			if got != test.want {
-				t.Fatalf("decode got: %s\nwant: %s\n", got, test.want)
+				t.Fatalf("decode got: '%s'\nwant: '%s'\n", got, test.want)
 			}
 		})
 	}
@@ -106,7 +106,7 @@ func Test_Encode(t *testing.T) {
 				t.Fatalf("encode err wanted but got none")
 			}
 			if enc != test.want {
-				t.Fatalf("encode got: %s\nwant: %s\n", enc, test.want)
+				t.Fatalf("encode got: '%s'\nwant: '%s'\n", enc, test.want)
 			}
 		})
 	}
@@ -132,3 +132,69 @@ func FuzzEncode(f *testing.F) {
 		}
 	})
 }
+
+func Test_EncodeText(t *testing.T) {
+	tests := []struct {
+		str     string
+		name    string
+		want    string
+		wantErr bool
+	}{
+		{
+			str:     "meh noob",
+			name:    "the noob",
+			want:    "meh bnoo",
+			wantErr: false,
+		},
+		{
+			str:     "The Putrefying Road In The 19th Extremity (...Somewhere Inside The Bowels Of The Endlessness...)",
+			name:    "the noob2",
+			want:    "The gyinrefPut dRoa In The h19t ityremExt ehermew.So(.. ideIns The elsBow Of The ..)ss.snelesEnd",
+			wantErr: false,
+		},
+		{
+			str:     "\xf2",
+			name:    "the invalid string",
+			want:    "",
+			wantErr: true,
+		},
+	}
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			o, _ := EncodeText(test.str)
+			if o != test.want {
+				t.Fatalf("encode got: '%s'\nwant: '%s'\n", o, test.want)
+			}
+		})
+	}
+}
+
+func Test_DecodeText(t *testing.T) {
+	tests := []struct {
+		str     string
+		name    string
+		want    string
+		wantErr bool
+	}{
+		{
+			str:     "The gyinrefPut dRoa In The h19t ityremExt ehermew.So(.. ideIns The elsBow Of The ..)ss.snelesEnd",
+			name:    "the puzzle",
+			want:    "The Putrefying Road In The 19th Extremity (...Somewhere Inside The Bowels Of The Endlessness...)",
+			wantErr: false,
+		},
+		{
+			str:     "\xf2",
+			name:    "the invalid string",
+			want:    "",
+			wantErr: true,
+		},
+	}
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			o, _ := DecodeText(test.str)
+			if o != test.want {
+				t.Fatalf("encode got: '%s'\nwant: '%s'\n", o, test.want)
+			}
+		})
+	}
+}