Refactor previous commits

Rewrite the `ManipulateNotes` function into `HandleNotes`, which
routes the note sub-commands to calls of newly-written `Parse*Note`
functions.  On successful parse, these functions return true, and
false otherwise.

Related tests are also refined.

4 files changed, 137 insertions, 54 deletions

diff --git a/todo.go b/todo.go
index d2bc7ab..645a880 100644
--- a/todo.go
+++ b/todo.go
@@ -166,7 +166,7 @@ func routeInput(command string, input string) {
 	case "ex", "expand":
 		app.ExpandTodo(input)
 	case "an", "n", "dn", "en":
-		app.ManipulateNotes(input)
+		app.HandleNotes(input)
 	case "gc":
 		app.GarbageCollect()
 	case "p", "prioritize":
diff --git a/todolist/app.go b/todolist/app.go
index 79e3aad..92ee64d 100644
--- a/todolist/app.go
+++ b/todolist/app.go
@@ -137,23 +137,33 @@ func (a *App) ExpandTodo(input string) {
 	fmt.Println("Todo expanded.")
 }
 
-func (a *App) ManipulateNotes(input string) {
+func (a *App) HandleNotes(input string) {
 	a.Load()
 	id := a.getId(input)
-	parser := &Parser{}
+	if id == -1 {
+		return
+	}
 	todo := a.TodoList.FindById(id)
 	if todo == nil {
 		fmt.Println("No such id.")
 		return
 	}
+	parser := &Parser{}
 
-	retStr := parser.ParseNotes(todo, input)
-	if retStr != "" {
-		a.Save()
-		if retStr != "list" {
-			fmt.Println("Notes " + retStr + "ed.")
-		}
+	if parser.ParseAddNote(todo, input) {
+		fmt.Println("Note added.")
+	} else if parser.ParseDeleteNote(todo, input) {
+		fmt.Println("Note deleted.")
+	} else if parser.ParseEditNote(todo, input) {
+		fmt.Println("Note edited.")
+	} else if parser.ParseShowNote(todo, input) {
+		groups := map[string][]*Todo{}
+		groups[""] = append(groups[""], todo)
+		formatter := NewFormatter(&GroupedTodos{Groups: groups})
+		formatter.Print(true)
+		return
 	}
+	a.Save()
 }
 
 func (a *App) ArchiveCompleted() {
diff --git a/todolist/parser.go b/todolist/parser.go
index 8f5e180..6ad8007 100644
--- a/todolist/parser.go
+++ b/todolist/parser.go
@@ -83,57 +83,66 @@ func (p *Parser) Contexts(input string) []string {
 	return p.matchWords(input, r)
 }
 
-func (p *Parser) ParseNotes(todo *Todo, input string) string {
-	r, _ := regexp.Compile(`(\w+) \d+\s*(.*)?`)
+func (p *Parser) ParseAddNote(todo *Todo, input string) bool {
+	r, _ := regexp.Compile(`^an\s+\d+\s+(.*)`)
 	matches := r.FindStringSubmatch(input)
-	switch matches[1] {
-	case "an":
-		todo.Notes = append(todo.Notes, matches[2])
-		return "add"
+	if len(matches) != 2 {
+		return false
+	}
 
-	case "n":
-		groups := map[string][]*Todo{}
-		groups[""] = append(groups[""], todo)
-		formatter := NewFormatter(&GroupedTodos{Groups: groups})
-		formatter.Print(true)
-		return "list"
+	todo.Notes = append(todo.Notes, matches[1])
+	return true
+}
 
-	case "dn":
-		rmid, err := p.getNoteID(matches[2])
-		if err != nil {
-			return ""
-		}
+func (p *Parser) ParseDeleteNote(todo *Todo, input string) bool {
+	r, _ := regexp.Compile(`^dn\s+\d+\s+(\d+)`)
+	matches := r.FindStringSubmatch(input)
+	if len(matches) != 2 {
+		return false
+	}
 
-		for id, _ := range todo.Notes {
-			if id == rmid {
-				todo.Notes = append(todo.Notes[:rmid], todo.Notes[rmid+1:]...)
-				return "delete"
-			}
-		}
-		fmt.Println("Could not found note id")
-		return ""
+	rmid, err := p.getNoteID(matches[1])
+	if err != nil {
+		return false
+	}
 
-	case "en":
-		r1, _ := regexp.Compile(`(\d)+\s+(.*)?`)
-		tail := r1.FindStringSubmatch(matches[2])
-		edid, err := p.getNoteID(tail[1])
-		if err != nil {
-			return ""
+	for id, _ := range todo.Notes {
+		if id == rmid {
+			todo.Notes = append(todo.Notes[:rmid], todo.Notes[rmid+1:]...)
+			return true
 		}
+	}
+	return false
+}
 
-		for id, _ := range todo.Notes {
-			if id == edid {
-				todo.Notes[id] = tail[2]
-				return "edit"
-			}
-		}
+func (p *Parser) ParseEditNote(todo *Todo, input string) bool {
+	r, _ := regexp.Compile(`^en\s+\d+\s+(\d+)\s+(.*)`)
+	matches := r.FindStringSubmatch(input)
+	if len(matches) != 3 {
+		return false
+	}
 
-		fmt.Println("Could not found note id")
-		return ""
+	edid, err := p.getNoteID(matches[1])
+	if err != nil {
+		return false
 	}
 
-	fmt.Println("Could not match command or id")
-	return ""
+	for id, _ := range todo.Notes {
+		if id == edid {
+			todo.Notes[id] = matches[2]
+			return true
+		}
+	}
+	return false
+}
+
+func (p *Parser) ParseShowNote(todo *Todo, input string) bool {
+	r, _ := regexp.Compile(`^n\s+\d+`)
+	matches := r.FindStringSubmatch(input)
+	if len(matches) != 1 {
+		return false
+	}
+	return true
 }
 
 func (p *Parser) getNoteID(input string) (int, error) {
diff --git a/todolist/parser_test.go b/todolist/parser_test.go
index 2c4fd25..313ad9f 100644
--- a/todolist/parser_test.go
+++ b/todolist/parser_test.go
@@ -74,25 +74,89 @@ func TestParseContexts(t *testing.T) {
 	}
 }
 
-func TestParseNotes(t *testing.T) {
+func TestParseAddNote(t *testing.T) {
+	parser := &Parser{}
+	todo := parser.ParseNewTodo("add write the test functions")
+
+	b1 := parser.ParseAddNote(todo, "an 1 TestPasrseAddNote")
+	b2 := parser.ParseAddNote(todo, "an 1 TestPasrseDeleteNote")
+	b3 := parser.ParseAddNote(todo, "an 1 TestPasrseEditNote")
+
+	if !b1 || !b2 || !b3 {
+		t.Error("Fail adding notes, expected 3 notes but", len(todo.Notes))
+	}
+}
+
+func TestParseDeleteNote(t *testing.T) {
+	parser := &Parser{}
+	todo := parser.ParseNewTodo("add buy notebook")
+
+	todo.Notes = append(todo.Notes, "ASUStek")
+	todo.Notes = append(todo.Notes, "Apple")
+	todo.Notes = append(todo.Notes, "Dell")
+	todo.Notes = append(todo.Notes, "Acer")
+
+	b1 := parser.ParseDeleteNote(todo, "dn 1 1")
+	b2 := parser.ParseDeleteNote(todo, "dn 1 1")
+
+	if !b1 || !b2 {
+		t.Error("Fail deleting notes, expected 2 notes left but", len(todo.Notes))
+	}
+
+	if todo.Notes[0] != "ASUStek" || todo.Notes[1] != "Acer" {
+		t.Error("Fail deleting notes,", todo.Notes[0], "and", todo.Notes[1], "are left")
+	}
+}
+
+func TestParseEditNote(t *testing.T) {
+	parser := &Parser{}
+	todo := parser.ParseNewTodo("add record the weather")
+
+	todo.Notes = append(todo.Notes, "Aug 29 Wed")
+	todo.Notes = append(todo.Notes, "Cloudy")
+	todo.Notes = append(todo.Notes, "40°C")
+	todo.Notes = append(todo.Notes, "Tokyo")
+
+	parser.ParseEditNote(todo, "en 1 0 Aug 29 Tue")
+	if todo.Notes[0] != "Aug 29 Tue" {
+		t.Error("Fail editing notes, note 0 should be \"Aug 29 Tue\" but got", todo.Notes[0])
+	}
+
+	parser.ParseEditNote(todo, "en 1 1 Sunny")
+	if todo.Notes[1] != "Sunny" {
+		t.Error("Fail editing notes, note 1 should be \"Sunny\" but got", todo.Notes[1])
+	}
+
+	parser.ParseEditNote(todo, "en 1 2 22°C")
+	if todo.Notes[2] != "22°C" {
+		t.Error("Fail editing notes, note 2 should be \"22°C\" but got", todo.Notes[2])
+	}
+
+	parser.ParseEditNote(todo, "en 1 3 Seoul")
+	if todo.Notes[3] != "Seoul" {
+		t.Error("Fail editing notes, note 3 should be \"Seoul\" but got", todo.Notes[3])
+	}
+}
+
+func TestHandleNotes(t *testing.T) {
 	parser := &Parser{}
 	todo := parser.ParseNewTodo("add search engine survey")
 
-	if parser.ParseNotes(todo, "an 1 www.google.com") != "add" {
+	if !parser.ParseAddNote(todo, "an 1 www.google.com") {
 		t.Error("Expected Notes to be added")
 	}
 	if todo.Notes[0] != "www.google.com" {
 		t.Error("Expected note 1 to be 'www.google.com' but got", todo.Notes[0])
 	}
 
-	if parser.ParseNotes(todo, "en 1 0 www.duckduckgo.com") != "edit" {
+	if !parser.ParseEditNote(todo, "en 1 0 www.duckduckgo.com") {
 		t.Error("Expected Notes to be editted")
 	}
 	if todo.Notes[0] != "www.duckduckgo.com" {
 		t.Error("Expected note 1 to be 'www.duckduckgo.com' but got", todo.Notes[0])
 	}
 
-	if parser.ParseNotes(todo, "dn 1 0") != "delete" {
+	if !parser.ParseDeleteNote(todo, "dn 1 0") {
 		t.Error("Expected Notes to be deleted")
 	}
 	if len(todo.Notes) != 0 {