tree is now filetree based

spike/review/reinvent/ezmded/server/tree.go

@@ -4,13 +4,17 @@ import (
 	"errors"
 	"io/ioutil"
 	"os"
+	"path"
+	"path/filepath"
 	"time"
 
 	yaml "gopkg.in/yaml.v2"
 )
 
+var errChainNotFound = errors.New("pid chain not found")
+
 type Tree struct {
-	path string
+	root string
 }
 
 type Branch struct {
@@ -25,9 +29,9 @@ type Pretty struct {
 	Title    string
 }
 
-func NewTree(path string) *Tree {
+func NewTree(root string) *Tree {
 	return &Tree{
-		path: path,
+		root: root,
 	}
 }
 
@@ -74,53 +78,108 @@ func (tree *Tree) GetPretty() (map[string]*Pretty, error) {
 }
 
 func (tree *Tree) Get() (map[string]Branch, error) {
-	b, err := ioutil.ReadFile(tree.path)
+	m := map[string]Branch{}
+	err := filepath.Walk(tree.root, func(p string, info os.FileInfo, err error) error {
+		if err != nil {
+			return err
+		}
+		if info.IsDir() {
+			return nil
+		}
+		if info.Name() != "meta.yaml" {
+			return nil
+		}
+		b, err := ioutil.ReadFile(p)
+		if err != nil {
+			return err
+		}
+		var branch Branch
+		if err := yaml.Unmarshal(b, &branch); err != nil {
+			return err
+		}
+		id := path.Base(path.Dir(p))
+		pidFullPath := path.Dir(path.Dir(p))
+		if pidFullPath != tree.root {
+			branch.PID = path.Base(pidFullPath)
+		} else {
+			branch.PID = ""
+		}
+		m[id] = branch
+		return nil
+	})
 	if os.IsNotExist(err) {
-		return map[string]Branch{}, nil
+		return m, nil
 	}
-	if err != nil {
-		return nil, err
-	}
-	var m map[string]Branch
-	err = yaml.Unmarshal(b, &m)
 	return m, err
 }
 
-func (tree *Tree) Set(m map[string]Branch) error {
-	b, err := yaml.Marshal(m)
-	if err != nil {
-		return err
-	}
-	return ioutil.WriteFile(tree.path, b, os.ModePerm)
-}
-
-func (tree *Tree) Del(id string) error {
+func (tree *Tree) fullIdAndMeta(id string) (string, Branch, error) {
 	m, err := tree.Get()
 	if err != nil {
-		return err
+		return "", Branch{}, err
 	}
 	branch, ok := m[id]
 	if !ok {
-		return nil
+		return "", Branch{}, errChainNotFound
 	}
-	branch.Updated = time.Now().UTC()
-	branch.Deleted = true
-	m[id] = branch
-	return tree.Set(m)
+	p := id
+	for branch.PID != "" {
+		p = path.Join(branch.PID, p)
+		branch, ok = m[branch.PID]
+		if !ok {
+			return "", Branch{}, errChainNotFound
+		}
+	}
+	return path.Join(tree.root, p), branch, nil
 }
 
-func (tree *Tree) Put(id string, branch Branch) error {
-	branch.Updated = time.Now().UTC()
-	if branch.Title == "" {
-		branch.Title = "Untitled (" + time.Now().UTC().String() + ")"
-	}
-	m, err := tree.Get()
+func (tree *Tree) putMeta(fullId string, branch Branch) error {
+	b, err := yaml.Marshal(branch)
 	if err != nil {
 		return err
 	}
-	if _, ok := m[branch.PID]; !ok && branch.PID != "" {
-		return errors.New("PID does not exist")
-	}
-	m[id] = branch
-	return tree.Set(m)
+	return ensureAndWrite(path.Join(fullId, "meta.yaml"), b)
+}
+
+func (tree *Tree) Del(id string) error {
+	fullId, meta, err := tree.fullIdAndMeta(id)
+	if err != nil {
+		if err == errChainNotFound {
+			return nil
+		}
+		return err
+	}
+
+	meta.Updated = time.Now().UTC()
+	meta.Deleted = true
+
+	return tree.putMeta(fullId, meta)
+}
+
+func (tree *Tree) Put(id string, branch Branch) error {
+	fullId, meta, err := tree.fullIdAndMeta(id)
+	if err == errChainNotFound {
+		if branch.PID != "" {
+			fullId, _, err = tree.fullIdAndMeta(branch.PID)
+			fullId = path.Join(fullId, id)
+		} else {
+			err = nil
+			fullId = path.Join(tree.root, fullId, id)
+		}
+	}
+	if err != nil {
+		return err
+	}
+
+	meta.Updated = time.Now().UTC()
+	if meta.Title == "" {
+		meta.Title = "Untitled (" + time.Now().UTC().String() + ")"
+	}
+	if branch.Title != "" {
+		meta.Title = branch.Title
+	}
+	meta.PID = branch.PID
+	meta.Deleted = branch.Deleted
+
+	return tree.putMeta(fullId, meta)
 }