Add task manager interface
Change-Id: I7a2f4b20907ba4bb12c900688aef059789884c1d
diff --git a/server/tm/README.md b/server/tm/README.md
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index 0000000..6b6e62d
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+++ b/server/tm/README.md
@@ -0,0 +1,76 @@
+# Task Management (tm) Package
+
+The `tm` package provides a comprehensive task management system with support for task dependencies, ownership, and various task states.
+
+## Overview
+
+This package defines interfaces and types for managing tasks in a system where:
+- Each task has a single owner
+- Tasks can be in various states (todo, in progress, completed, etc.)
+- Tasks have priorities and due dates
+
+## Core Components
+
+### Types (`types.go`)
+
+- **Task**: The main task entity with all task properties
+- **TaskStatus**: Enum for task states (pending, in progress, completed, etc.)
+- **TaskPriority**: Enum for task priorities (low, medium, high, urgent)
+- **Owner**: Represents a task owner
+
+- **TaskFilter**: For filtering task queries
+- **Request/Response types**: For API operations
+
+### Interfaces (`interface.go`)
+
+#### TaskManager
+The main interface for task management operations:
+- CRUD operations for tasks
+- Task status management (start, complete)
+- Task queries and filtering
+- Task archiving
+
+### Errors (`errors.go`)
+
+Comprehensive error definitions:
+- Common task management errors
+- Task-specific errors with context
+
+## Key Features
+
+### Task States
+- **To Do**: Task is created but not started
+- **In Progress**: Task is currently being worked on
+- **Completed**: Task is finished
+- **Archived**: Task is archived (soft delete)
+
+### Task Priorities
+- **Low**: Low priority tasks
+- **Medium**: Normal priority tasks
+- **High**: High priority tasks
+
+### Filtering and Queries
+- Filter by owner, status, priority
+- Filter by date ranges
+- Pagination support
+
+## Usage Example
+
+```go
+// Create a task manager implementation
+var taskManager tm.TaskManager
+
+// Create a new task
+task, err := taskManager.CreateTask(ctx, &tm.TaskCreateRequest{
+ Title: "Implement user authentication",
+ Description: "Add login and registration functionality",
+ OwnerID: "user123",
+ Priority: tm.PriorityHigh,
+})
+
+// Start a task
+task, err = taskManager.StartTask(ctx, "task1")
+
+// Complete a task
+task, err = taskManager.CompleteTask(ctx, "task1")
+```
diff --git a/server/tm/errors.go b/server/tm/errors.go
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index 0000000..55dd037
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+++ b/server/tm/errors.go
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+package tm
+
+import (
+ "errors"
+ "fmt"
+)
+
+// Common task management errors
+var (
+ ErrTaskNotFound = errors.New("task not found")
+ ErrOwnerNotFound = errors.New("owner not found")
+ ErrInvalidTaskStatus = errors.New("invalid task status")
+ ErrInvalidTaskPriority = errors.New("invalid task priority")
+ ErrTaskAlreadyCompleted = errors.New("task is already completed")
+ ErrTaskAlreadyArchived = errors.New("task is already archived")
+ ErrTaskNotStarted = errors.New("task is not started")
+ ErrTaskNotInProgress = errors.New("task is not in progress")
+ ErrInvalidOwner = errors.New("invalid owner")
+ ErrInvalidTaskData = errors.New("invalid task data")
+)
+
+// TaskError represents a task-specific error with additional context
+type TaskError struct {
+ TaskID string
+ Op string
+ Err error
+}
+
+func (e *TaskError) Error() string {
+ if e.TaskID != "" {
+ return fmt.Sprintf("task %s: %s: %v", e.TaskID, e.Op, e.Err)
+ }
+ return fmt.Sprintf("%s: %v", e.Op, e.Err)
+}
+
+func (e *TaskError) Unwrap() error {
+ return e.Err
+}
+
+// NewTaskError creates a new TaskError
+func NewTaskError(taskID, op string, err error) *TaskError {
+ return &TaskError{
+ TaskID: taskID,
+ Op: op,
+ Err: err,
+ }
+}
diff --git a/server/tm/interface.go b/server/tm/interface.go
new file mode 100644
index 0000000..93b0f29
--- /dev/null
+++ b/server/tm/interface.go
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+package tm
+
+import (
+ "context"
+)
+
+// TaskManager defines the interface for task management operations
+type TaskManager interface {
+ // Task operations
+ CreateTask(ctx context.Context, req *TaskCreateRequest) (*Task, error)
+ GetTask(ctx context.Context, id string) (*Task, error)
+ UpdateTask(ctx context.Context, id string, req *TaskUpdateRequest) (*Task, error)
+ ArchiveTask(ctx context.Context, id string) error
+ ListTasks(ctx context.Context, filter *TaskFilter, page, pageSize int) (*TaskList, error)
+
+ // Task status operations
+ StartTask(ctx context.Context, id string) (*Task, error)
+ CompleteTask(ctx context.Context, id string) (*Task, error)
+
+ // Task queries
+ GetTasksByOwner(ctx context.Context, ownerID string, page, pageSize int) (*TaskList, error)
+ GetTasksByStatus(ctx context.Context, status TaskStatus, page, pageSize int) (*TaskList, error)
+ GetTasksByPriority(ctx context.Context, priority TaskPriority, page, pageSize int) (*TaskList, error)
+}
diff --git a/server/tm/types.go b/server/tm/types.go
new file mode 100644
index 0000000..781d63d
--- /dev/null
+++ b/server/tm/types.go
@@ -0,0 +1,84 @@
+package tm
+
+import (
+ "time"
+)
+
+// TaskStatus represents the current status of a task
+type TaskStatus string
+
+const (
+ StatusToDo TaskStatus = "todo"
+ StatusInProgress TaskStatus = "in_progress"
+ StatusCompleted TaskStatus = "completed"
+ StatusArchived TaskStatus = "archived"
+)
+
+// TaskPriority represents the priority level of a task
+type TaskPriority string
+
+const (
+ PriorityLow TaskPriority = "low"
+ PriorityMedium TaskPriority = "medium"
+ PriorityHigh TaskPriority = "high"
+)
+
+// Owner represents a task owner
+type Owner struct {
+ ID string `json:"id"`
+ Name string `json:"name"`
+}
+
+// Task represents a single task in the system
+type Task struct {
+ ID string `json:"id"`
+ Title string `json:"title"`
+ Description string `json:"description"`
+ Owner Owner `json:"owner"`
+ Status TaskStatus `json:"status"`
+ Priority TaskPriority `json:"priority"`
+ CreatedAt time.Time `json:"created_at"`
+ UpdatedAt time.Time `json:"updated_at"`
+ DueDate *time.Time `json:"due_date,omitempty"`
+ CompletedAt *time.Time `json:"completed_at,omitempty"`
+ ArchivedAt *time.Time `json:"archived_at,omitempty"`
+}
+
+// TaskFilter represents filters for querying tasks
+type TaskFilter struct {
+ OwnerID *string `json:"owner_id,omitempty"`
+ Status *TaskStatus `json:"status,omitempty"`
+ Priority *TaskPriority `json:"priority,omitempty"`
+ DueBefore *time.Time `json:"due_before,omitempty"`
+ DueAfter *time.Time `json:"due_after,omitempty"`
+ CreatedAfter *time.Time `json:"created_after,omitempty"`
+ CreatedBefore *time.Time `json:"created_before,omitempty"`
+}
+
+// TaskCreateRequest represents the data needed to create a new task
+type TaskCreateRequest struct {
+ Title string `json:"title" validate:"required"`
+ Description string `json:"description"`
+ OwnerID string `json:"owner_id" validate:"required"`
+ Priority TaskPriority `json:"priority"`
+ DueDate *time.Time `json:"due_date,omitempty"`
+}
+
+// TaskUpdateRequest represents the data needed to update an existing task
+type TaskUpdateRequest struct {
+ Title *string `json:"title,omitempty"`
+ Description *string `json:"description,omitempty"`
+ OwnerID *string `json:"owner_id,omitempty"`
+ Status *TaskStatus `json:"status,omitempty"`
+ Priority *TaskPriority `json:"priority,omitempty"`
+ DueDate *time.Time `json:"due_date,omitempty"`
+}
+
+// TaskList represents a paginated list of tasks
+type TaskList struct {
+ Tasks []*Task `json:"tasks"`
+ TotalCount int `json:"total_count"`
+ Page int `json:"page"`
+ PageSize int `json:"page_size"`
+ HasMore bool `json:"has_more"`
+}