package handlers

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

	"task-dashboard/internal/models"
	"task-dashboard/internal/store"

	_ "github.com/mattn/go-sqlite3"
)

// MockCalendarClient implements GoogleCalendarAPI interface for testing
type MockCalendarClient struct {
	Events []models.CalendarEvent
	Err    error
}

func (m *MockCalendarClient) GetUpcomingEvents(ctx context.Context, maxResults int) ([]models.CalendarEvent, error) {
	return m.Events, m.Err
}

func (m *MockCalendarClient) GetEventsByDateRange(ctx context.Context, start, end time.Time) ([]models.CalendarEvent, error) {
	return m.Events, m.Err
}

func setupTestStore(t *testing.T) *store.Store {
	t.Helper()
	tempDir := t.TempDir()
	dbPath := filepath.Join(tempDir, "test.db")
	migrationDir := filepath.Join(tempDir, "migrations")

	if err := os.MkdirAll(migrationDir, 0755); err != nil {
		t.Fatalf("Failed to create migration dir: %v", err)
	}

	schema := `
		CREATE TABLE IF NOT EXISTS tasks (
			id TEXT PRIMARY KEY,
			content TEXT NOT NULL,
			description TEXT,
			project_id TEXT,
			project_name TEXT,
			due_date DATETIME,
			priority INTEGER DEFAULT 1,
			completed BOOLEAN DEFAULT FALSE,
			labels TEXT,
			url TEXT,
			created_at DATETIME,
			updated_at DATETIME DEFAULT CURRENT_TIMESTAMP
		);
		CREATE TABLE IF NOT EXISTS meals (
			id TEXT PRIMARY KEY,
			recipe_name TEXT NOT NULL,
			date DATETIME,
			meal_type TEXT,
			recipe_url TEXT,
			updated_at DATETIME DEFAULT CURRENT_TIMESTAMP
		);
		CREATE TABLE IF NOT EXISTS boards (
			id TEXT PRIMARY KEY,
			name TEXT NOT NULL,
			updated_at DATETIME DEFAULT CURRENT_TIMESTAMP
		);
		CREATE TABLE IF NOT EXISTS cards (
			id TEXT PRIMARY KEY,
			name TEXT NOT NULL,
			board_id TEXT NOT NULL,
			list_id TEXT,
			list_name TEXT,
			due_date DATETIME,
			url TEXT,
			updated_at DATETIME DEFAULT CURRENT_TIMESTAMP
		);
	`
	if err := os.WriteFile(filepath.Join(migrationDir, "001_init.sql"), []byte(schema), 0644); err != nil {
		t.Fatalf("Failed to write migration file: %v", err)
	}

	// Initialize store (this creates tables)
	s, err := store.New(dbPath, migrationDir)
	if err != nil {
		t.Fatalf("Failed to create store: %v", err)
	}
	return s
}

func TestBuildTimeline(t *testing.T) {
	s := setupTestStore(t)
	
	// Fix a base time: 2023-01-01 08:00:00
	baseTime := time.Date(2023, 1, 1, 8, 0, 0, 0, time.UTC)
	
	// Task: 10:00
	taskDate := baseTime.Add(2 * time.Hour)
	s.SaveTasks([]models.Task{
		{ID: "t1", Content: "Task 1", DueDate: &taskDate},
	})

	// Meal: Lunch (defaults to 12:00)
	mealDate := baseTime // Date part matters
	s.SaveMeals([]models.Meal{
		{ID: "m1", RecipeName: "Lunch", Date: mealDate, MealType: "lunch"},
	})

	// Card: 14:00
	cardDate := baseTime.Add(6 * time.Hour)
	s.SaveBoards([]models.Board{
		{
			ID: "b1", 
			Name: "Board 1",
			Cards: []models.Card{
				{ID: "c1", Name: "Card 1", DueDate: &cardDate, ListID: "l1"},
			},
		},
	})

	// Calendar Event: 09:00
	eventDate := baseTime.Add(1 * time.Hour)
	mockCal := &MockCalendarClient{
		Events: []models.CalendarEvent{
			{ID: "e1", Summary: "Event 1", Start: eventDate, End: eventDate.Add(1 * time.Hour)},
		},
	}

	// Test Range: Full Day
	start := time.Date(2023, 1, 1, 0, 0, 0, 0, time.UTC)
	end := time.Date(2023, 1, 2, 0, 0, 0, 0, time.UTC)

	items, err := BuildTimeline(context.Background(), s, mockCal, start, end)
	if err != nil {
		t.Fatalf("BuildTimeline failed: %v", err)
	}

	if len(items) != 4 {
		t.Errorf("Expected 4 items, got %d", len(items))
	}

	// Expected Order:
	// 1. Event (09:00)
	// 2. Task (10:00)
	// 3. Meal (12:00)
	// 4. Card (14:00)

	if items[0].Type != models.TimelineItemTypeEvent {
		t.Errorf("Expected item 0 to be Event, got %s", items[0].Type)
	}
	if items[1].Type != models.TimelineItemTypeTask {
		t.Errorf("Expected item 1 to be Task, got %s", items[1].Type)
	}
	if items[2].Type != models.TimelineItemTypeMeal {
		t.Errorf("Expected item 2 to be Meal, got %s", items[2].Type)
	}
	if items[3].Type != models.TimelineItemTypeCard {
		t.Errorf("Expected item 3 to be Card, got %s", items[3].Type)
	}
}