package filesystem_test

import (
	"os"
	"path/filepath"
	"testing"

	"github.com/jfraeys/fetch_ml/internal/domain"
	"github.com/jfraeys/fetch_ml/internal/queue/filesystem"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
)

// TestNewQueue tests queue creation
func TestNewQueue(t *testing.T) {
	t.Parallel()

	tmpDir := t.TempDir()
	queueRoot := filepath.Join(tmpDir, "queue")

	q, err := filesystem.NewQueue(queueRoot)
	require.NoError(t, err)
	require.NotNil(t, q)
	defer q.Close()

	// Verify directories were created
	for _, dir := range []string{"pending/entries", "running", "finished", "failed"} {
		path := filepath.Join(queueRoot, dir)
		info, err := os.Stat(path)
		require.NoError(t, err, "Directory %s should exist", dir)
		assert.True(t, info.IsDir())
	}
}

// TestNewQueueEmptyRoot tests queue creation with empty root
func TestNewQueueEmptyRoot(t *testing.T) {
	t.Parallel()

	_, err := filesystem.NewQueue("")
	require.Error(t, err)
	assert.Contains(t, err.Error(), "root is required")
}

// TestClose tests queue closing
func TestClose(t *testing.T) {
	t.Parallel()

	tmpDir := t.TempDir()
	q, err := filesystem.NewQueue(tmpDir)
	require.NoError(t, err)

	err = q.Close()
	require.NoError(t, err)
}

// TestAddTask tests adding tasks
func TestAddTask(t *testing.T) {
	t.Parallel()

	tmpDir := t.TempDir()
	q, err := filesystem.NewQueue(tmpDir)
	require.NoError(t, err)
	defer q.Close()

	task := &domain.Task{
		ID:      "test-task-1",
		Status:  "pending",
		Args:    "test args",
		Output:  "test output",
	}

	err = q.AddTask(task)
	require.NoError(t, err)

	// Verify file was created
	taskFile := filepath.Join(tmpDir, "pending", "entries", "test-task-1.json")
	_, err = os.Stat(taskFile)
	require.NoError(t, err)
}

// TestAddTaskNil tests adding nil task
func TestAddTaskNil(t *testing.T) {
	t.Parallel()

	tmpDir := t.TempDir()
	q, err := filesystem.NewQueue(tmpDir)
	require.NoError(t, err)
	defer q.Close()

	err = q.AddTask(nil)
	require.Error(t, err)
	assert.Contains(t, err.Error(), "task is nil")
}

// TestAddTaskInvalidID tests adding task with invalid ID
func TestAddTaskInvalidID(t *testing.T) {
	t.Parallel()

	tmpDir := t.TempDir()
	q, err := filesystem.NewQueue(tmpDir)
	require.NoError(t, err)
	defer q.Close()

	task := &domain.Task{
		ID:     "invalid/id/with/slashes",
		Status: "pending",
	}

	err = q.AddTask(task)
	require.Error(t, err)
	assert.Contains(t, err.Error(), "invalid task ID")
}

// TestGetTask tests retrieving tasks
func TestGetTask(t *testing.T) {
	t.Parallel()

	tmpDir := t.TempDir()
	q, err := filesystem.NewQueue(tmpDir)
	require.NoError(t, err)
	defer q.Close()

	task := &domain.Task{
		ID:      "get-task-1",
		Status:  "pending",
		Args:    "test args",
	}

	err = q.AddTask(task)
	require.NoError(t, err)

	retrieved, err := q.GetTask("get-task-1")
	require.NoError(t, err)
	assert.Equal(t, task.ID, retrieved.ID)
	assert.Equal(t, task.Status, retrieved.Status)
	assert.Equal(t, task.Args, retrieved.Args)
}

// TestGetTaskNotFound tests retrieving nonexistent task
func TestGetTaskNotFound(t *testing.T) {
	t.Parallel()

	tmpDir := t.TempDir()
	q, err := filesystem.NewQueue(tmpDir)
	require.NoError(t, err)
	defer q.Close()

	_, err = q.GetTask("nonexistent-task")
	require.Error(t, err)
	assert.Contains(t, err.Error(), "task not found")
}

// TestGetTaskInvalidID tests retrieving with invalid ID
func TestGetTaskInvalidID(t *testing.T) {
	t.Parallel()

	tmpDir := t.TempDir()
	q, err := filesystem.NewQueue(tmpDir)
	require.NoError(t, err)
	defer q.Close()

	_, err = q.GetTask("invalid/id")
	require.Error(t, err)
	assert.Contains(t, err.Error(), "invalid task ID")
}

// TestListTasks tests listing all tasks
func TestListTasks(t *testing.T) {
	t.Parallel()

	tmpDir := t.TempDir()
	q, err := filesystem.NewQueue(tmpDir)
	require.NoError(t, err)
	defer q.Close()

	// Add multiple tasks
	tasks := []*domain.Task{
		{ID: "list-task-1", Status: "pending"},
		{ID: "list-task-2", Status: "pending"},
		{ID: "list-task-3", Status: "pending"},
	}

	for _, task := range tasks {
		err := q.AddTask(task)
		require.NoError(t, err)
	}

	listed, err := q.ListTasks()
	require.NoError(t, err)
	assert.Len(t, listed, 3)
}

// TestListTasksEmpty tests listing with no tasks
func TestListTasksEmpty(t *testing.T) {
	t.Parallel()

	tmpDir := t.TempDir()
	q, err := filesystem.NewQueue(tmpDir)
	require.NoError(t, err)
	defer q.Close()

	listed, err := q.ListTasks()
	require.NoError(t, err)
	assert.Empty(t, listed)
}

// TestCancelTask tests canceling tasks
func TestCancelTask(t *testing.T) {
	t.Parallel()

	tmpDir := t.TempDir()
	q, err := filesystem.NewQueue(tmpDir)
	require.NoError(t, err)
	defer q.Close()

	task := &domain.Task{
		ID:      "cancel-task-1",
		Status:  "pending",
	}

	err = q.AddTask(task)
	require.NoError(t, err)

	// Verify file exists
	taskFile := filepath.Join(tmpDir, "pending", "entries", "cancel-task-1.json")
	_, err = os.Stat(taskFile)
	require.NoError(t, err)

	// Cancel task
	err = q.CancelTask("cancel-task-1")
	require.NoError(t, err)

	// Verify file is gone
	_, err = os.Stat(taskFile)
	require.True(t, os.IsNotExist(err))
}

// TestCancelTaskNotFound tests canceling nonexistent task
func TestCancelTaskNotFound(t *testing.T) {
	t.Parallel()

	tmpDir := t.TempDir()
	q, err := filesystem.NewQueue(tmpDir)
	require.NoError(t, err)
	defer q.Close()

	// Should not error for nonexistent task
	err = q.CancelTask("nonexistent-task")
	require.NoError(t, err)
}

// TestCancelTaskInvalidID tests canceling with invalid ID
func TestCancelTaskInvalidID(t *testing.T) {
	t.Parallel()

	tmpDir := t.TempDir()
	q, err := filesystem.NewQueue(tmpDir)
	require.NoError(t, err)
	defer q.Close()

	err = q.CancelTask("invalid/id")
	require.Error(t, err)
	assert.Contains(t, err.Error(), "invalid task ID")
}

// TestUpdateTask tests updating tasks
func TestUpdateTask(t *testing.T) {
	t.Parallel()

	tmpDir := t.TempDir()
	q, err := filesystem.NewQueue(tmpDir)
	require.NoError(t, err)
	defer q.Close()

	task := &domain.Task{
		ID:      "update-task-1",
		Status:  "pending",
		Args:    "original args",
	}

	err = q.AddTask(task)
	require.NoError(t, err)

	// Update task
	updated := &domain.Task{
		ID:      "update-task-1",
		Status:  "running",
		Args:    "updated args",
		Output:  "new output",
	}

	err = q.UpdateTask(updated)
	require.NoError(t, err)

	// Verify update
	retrieved, err := q.GetTask("update-task-1")
	require.NoError(t, err)
	assert.Equal(t, "running", retrieved.Status)
	assert.Equal(t, "updated args", retrieved.Args)
	assert.Equal(t, "new output", retrieved.Output)
}

// TestUpdateTaskNil tests updating with nil task
func TestUpdateTaskNil(t *testing.T) {
	t.Parallel()

	tmpDir := t.TempDir()
	q, err := filesystem.NewQueue(tmpDir)
	require.NoError(t, err)
	defer q.Close()

	err = q.UpdateTask(nil)
	require.Error(t, err)
	assert.Contains(t, err.Error(), "task is nil")
}

// TestUpdateTaskNotFound tests updating nonexistent task
func TestUpdateTaskNotFound(t *testing.T) {
	t.Parallel()

	tmpDir := t.TempDir()
	q, err := filesystem.NewQueue(tmpDir)
	require.NoError(t, err)
	defer q.Close()

	task := &domain.Task{
		ID:      "nonexistent-task",
		Status:  "pending",
	}

	err = q.UpdateTask(task)
	require.Error(t, err)
	assert.Contains(t, err.Error(), "task not found")
}

// TestUpdateTaskInvalidID tests updating with invalid ID
func TestUpdateTaskInvalidID(t *testing.T) {
	t.Parallel()

	tmpDir := t.TempDir()
	q, err := filesystem.NewQueue(tmpDir)
	require.NoError(t, err)
	defer q.Close()

	task := &domain.Task{
		ID:      "invalid/id",
		Status:  "pending",
	}

	err = q.UpdateTask(task)
	require.Error(t, err)
	assert.Contains(t, err.Error(), "invalid task ID")
}