add -dedupe to move dupe TODO and SCHEDULED to DONE

cmd/main.go

@@ -7,6 +7,8 @@ import (
 	"log"
 	"os"
 
+	"slices"
+
 	"gitea.inhome.blapointe.com/gogs/pttodo/pttodo"
 
 	"gopkg.in/yaml.v2"
@@ -32,6 +34,8 @@ func _main() error {
 		return merge(&config)
 	} else if config.archive != "" {
 		return archive(&config)
+	} else if config.dedupe {
+		return dedupe(&config)
 	} else {
 		if err := add(&config); err != nil {
 			return err
@@ -43,6 +47,54 @@ func _main() error {
 	}
 }
 
+func dedupe(config *config) error {
+	baseReader, err := filePathReader(config.target)
+	if err != nil {
+		return err
+	}
+	baseB, err := ioutil.ReadAll(baseReader)
+	if err != nil {
+		return err
+	}
+
+	var base pttodo.Root
+	if err := yaml.Unmarshal(baseB, &base); err != nil {
+		return err
+	}
+
+	do := func(todos []pttodo.Todo) []pttodo.Todo {
+		i := len(todos) - 1
+		for i >= 0 {
+			j := slices.IndexFunc(todos, func(todo pttodo.Todo) bool {
+				return todo.Equals(todos[i])
+			})
+			if j >= 0 && j != i {
+				todos[j] = todos[i]
+				base.Done = append(base.Done, todos[j])
+				todos = todos[:i]
+			}
+			i -= 1
+		}
+		return todos
+	}
+
+	base.Todo = do(base.Todo)
+	base.Scheduled = do(base.Scheduled)
+
+	if tmppath, err := marshalRootToTempFile(base); err != nil {
+		return err
+	} else if config.dryRun {
+		log.Println("===before===")
+		_dump(os.Stdout, []string{config.target}, config.tags, config.search, config.root)
+		log.Println("===after===")
+		_dump(os.Stdout, []string{tmppath}, config.tags, config.search, config.root)
+	} else if err := rename(tmppath, config.target); err != nil {
+		return err
+	}
+
+	return nil
+}
+
 func archive(config *config) error {
 	if config.archive == "" {
 		return nil