wip: implement business logic (rough draft)

There are a ton of visual warts, but the actual logic seems sound so
far.

1 files changed, 68 insertions, 9 deletions

diff --git a/cmds.go b/cmds.go
index 26cded5..241897c 100644
--- a/cmds.go
+++ b/cmds.go
@@ -1,20 +1,79 @@
 package main
 
 import (
+	"encoding/binary"
+	"encoding/json"
 	"fmt"
+
+	"go.etcd.io/bbolt"
 )
 
-func cmdAdd(task string) error {
-	fmt.Println("added task: ", task)
-	return nil
+type taskType struct {
+	What  string `json:"what"`
+	Done  bool   `json:"done"`
+	Index uint64 `json:"index"`
+}
+
+// itob returns an 8-byte big endian representation of v.
+func itob(v uint64) []byte {
+	b := make([]byte, 8)
+	binary.BigEndian.PutUint64(b, v)
+	return b
+}
+
+func (ctrl controller) cmdAdd(task string) error {
+	return ctrl.db.Update(func(tx *bbolt.Tx) error {
+		taskBucket := tx.Bucket(ctrl.tasksBucketName)
+
+		// Update call, so ignore the error check. See
+		// pkg.go.dev/go.etcd.io/bbolt#section-readme
+		index, _ := taskBucket.NextSequence()
+		t := taskType{
+			What:  task,
+			Done:  false,
+			Index: index,
+		}
+
+		buf, err := json.Marshal(t)
+		if err != nil {
+			return fmt.Errorf("can't marshal: %w", err)
+		}
+
+		return taskBucket.Put(itob(index), buf)
+	})
 }
 
-func cmdDo(taskIndex int) error {
-	fmt.Println("completed task: ", taskIndex)
-	return nil
+func (ctrl controller) cmdDo(taskIndex int) error {
+	return ctrl.db.Update(func(tx *bbolt.Tx) error {
+		taskBucket := tx.Bucket(ctrl.tasksBucketName)
+		ttBytes := taskBucket.Get(itob(uint64(taskIndex)))
+
+		var tt taskType
+		if err := json.Unmarshal(ttBytes, &tt); err != nil {
+			return fmt.Errorf("can't unmarshal: %w", err)
+		}
+
+		tt.Done = true
+
+		buf, err := json.Marshal(tt)
+		if err != nil {
+			return fmt.Errorf("can't marshal: %w", err)
+		}
+
+		return taskBucket.Put(itob(uint64(taskIndex)), buf)
+	})
 }
 
-func cmdList() error {
-	fmt.Println("listed pending tasks")
-	return nil
+func (ctrl controller) cmdList() error {
+	return ctrl.db.View(func(tx *bbolt.Tx) error {
+		// Assume bucket exists and has keys
+		b := tx.Bucket([]byte(ctrl.tasksBucketName))
+
+		b.ForEach(func(k, v []byte) error {
+			fmt.Printf("%s. %s\n", k, v)
+			return nil
+		})
+
+		return nil
+	})
 }