Add basic library code to manage projects, activities and times.

lib/activities.go

@@ -0,0 +1,121 @@
+package lib
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+	"path/filepath"
+)
+
+// Activity entity as defined by the specification.
+type Activity struct {
+	ID    string `json:"id"`
+	Title string `json:"title"`
+}
+
+// GetActivities retrieves all stored activity instances of a project.
+func GetActivities(project *Project) ([]*Activity, error) {
+	folder, folderErr := getActivitiesFolder(project.ID)
+	if folderErr != nil {
+		return nil, folderErr
+	}
+
+	dirErr := os.MkdirAll(folder, 0o750)
+	if dirErr != nil {
+		return nil, dirErr
+	}
+
+	files, filesErr := os.ReadDir(folder)
+	if filesErr != nil {
+		return nil, filesErr
+	}
+
+	activities := []*Activity{}
+	for _, file := range files {
+		activity, fileErr := readActivity(filepath.Join(folder, file.Name()))
+		if fileErr != nil {
+			return nil, fileErr
+		}
+		activities = append(activities, activity)
+	}
+
+	return activities, nil
+}
+
+// SetActivity persists an activity.
+func SetActivity(project *Project, activity *Activity) error {
+	uuid, uuidErr := newUUID()
+	if uuidErr != nil {
+		return uuidErr
+	}
+
+	activity.ID = uuid
+
+	file, fileErr := getActivityFile(project.ID, uuid)
+	if fileErr != nil {
+		return fileErr
+	}
+
+	return writeActivity(file, activity)
+}
+
+// readActivity reads an activity from a file and converts it into an entity instance.
+func readActivity(filename string) (*Activity, error) {
+	file, err := os.Open(filename)
+	if err != nil {
+		return nil, err
+	}
+	defer file.Close()
+
+	project := Activity{}
+	if err := json.NewDecoder(file).Decode(&project); err != nil {
+		return nil, err
+	}
+
+	return &project, nil
+}
+
+// writeActivity writes an activity instance to a file.
+func writeActivity(filename string, activity *Activity) error {
+	dirErr := os.MkdirAll(filepath.Dir(filename), 0o750)
+	if dirErr != nil {
+		return dirErr
+	}
+	fmt.Println("success")
+
+	file, fileErr := os.Create(filename)
+	if fileErr != nil {
+		return fileErr
+	}
+	defer file.Close()
+
+	encoder := json.NewEncoder(file)
+	encoder.SetIndent("", "    ")
+
+	jsonErr := encoder.Encode(activity)
+	if jsonErr != nil {
+		return jsonErr
+	}
+
+	return nil
+}
+
+// getActivitiesFolder returns the folder to store activity entity files in.
+func getActivitiesFolder(projectID string) (string, error) {
+	folder, err := getDataDir("activities")
+	if err != nil {
+		return "", err
+	}
+
+	return filepath.Join(folder, projectID), nil
+}
+
+// getActivityFile returns the file name for an activity entity instance.
+func getActivityFile(projectID string, name string) (string, error) {
+	folder, err := getActivitiesFolder(projectID)
+	if err != nil {
+		return "", err
+	}
+
+	return filepath.Join(folder, name+".json"), nil
+}