package scanner

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

	"donniemarko/internal/note"
)

func TestScanner_DetectsNewFile(t *testing.T) {
	tmpDir := t.TempDir()
	scanner := NewScanner(tmpDir)

	scanner.Scan() // Initial scan

	os.WriteFile(filepath.Join(tmpDir, "new.md"), []byte("# New"), 0644)

	changes, _ := scanner.Scan()

	if len(changes) != 1 || changes[0].Type != Created {
		t.Error("should detect new file")
	}
}

func TestScanner_DetectChanges(t *testing.T) {
	tmpDir := t.TempDir()
	filePath := filepath.Join(tmpDir, "test.md")

	// Initial state
	os.WriteFile(filePath, []byte("# Original"), 0644)

	scanner := NewScanner(tmpDir)
	changes, _ := scanner.Scan()
	originalModTime := changes[0].ModTime

	// Wait and modify
	time.Sleep(10 * time.Millisecond)
	os.WriteFile(filePath, []byte("# Modified"), 0644)

	changes, _ = scanner.Scan()
	newModTime := changes[0].ModTime

	if !newModTime.After(originalModTime) {
		t.Error("should detect file modification")
	}

	if changes[0].Type != Modified {
		t.Errorf("Last state should be modified, got '%v'\n", changes[0].Type)
	}

	newPath := filepath.Join(tmpDir, "test_renamed.md")
	os.Rename(filePath, newPath)
	changes, _ = scanner.Scan()

	if changes[0].Path != newPath {
		t.Errorf("Should find renamed file '%s'. Got '%s'\n", newPath, changes[0].Path)
	}
}

func TestScanner_SeedExisting_PrunesMissing(t *testing.T) {
	tmpDir := t.TempDir()
	sc := NewScanner(tmpDir)

	n := note.NewNote()
	n.Path = "missing.md"
	n.UpdatedAt = time.Now()

	sc.SeedExisting([]*note.Note{n})

	changes, err := sc.Scan()
	if err != nil {
		t.Fatalf("scan error: %v", err)
	}

	if len(changes) != 1 {
		t.Fatalf("expected 1 change, got %d", len(changes))
	}
	if changes[0].Type != Deleted {
		t.Fatalf("expected Deleted change, got %v", changes[0].Type)
	}
}

func TestScanner_SeedExisting_KeepsExisting(t *testing.T) {
	tmpDir := t.TempDir()
	filePath := filepath.Join(tmpDir, "kept.md")

	os.WriteFile(filePath, []byte("# Kept"), 0644)

	sc := NewScanner(tmpDir)

	n := note.NewNote()
	n.Path = "kept.md"
	n.UpdatedAt = time.Now()

	sc.SeedExisting([]*note.Note{n})

	changes, err := sc.Scan()
	if err != nil {
		t.Fatalf("scan error: %v", err)
	}

	if len(changes) != 0 {
		t.Fatalf("expected 0 changes, got %d", len(changes))
	}
}