package files

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

func TestList(t *testing.T) {
	dir := t.TempDir()

	subdir := filepath.Join(dir, "subdir")
	if err := os.MkdirAll(subdir, 0o755); err != nil {
		t.Fatal(err)
	}
	f1 := filepath.Join(dir, "a.txt")
	if err := os.WriteFile(f1, []byte("hello"), 0o644); err != nil {
		t.Fatal(err)
	}
	f2 := filepath.Join(dir, "b.log")
	if err := os.WriteFile(f2, []byte("world"), 0o644); err != nil {
		t.Fatal(err)
	}

	res, err := List(dir, nil, 1, 50)
	if err != nil {
		t.Fatalf("List: %v", err)
	}
	if res.Total != 3 { // subdir, a.txt, b.log
		t.Errorf("Total=%d, want 3", res.Total)
	}
	if res.HasMore {
		t.Errorf("HasMore=true, want false")
	}
}

func TestListPaged(t *testing.T) {
	dir := t.TempDir()
	for i := 0; i < 10; i++ {
		if err := os.WriteFile(filepath.Join(dir, string(rune('a'+i))+".txt"), []byte("x"), 0o644); err != nil {
			t.Fatal(err)
		}
	}

	page1, err := List(dir, nil, 1, 3)
	if err != nil {
		t.Fatalf("page1: %v", err)
	}
	if len(page1.Entries) != 3 {
		t.Errorf("page1 len=%d, want 3", len(page1.Entries))
	}
	if !page1.HasMore {
		t.Errorf("page1.HasMore=false, want true")
	}

	page2, err := List(dir, nil, 2, 3)
	if err != nil {
		t.Fatalf("page2: %v", err)
	}
	if len(page2.Entries) != 3 {
		t.Errorf("page2 len=%d, want 3", len(page2.Entries))
	}

	page4, err := List(dir, nil, 4, 3)
	if err != nil {
		t.Fatalf("page4: %v", err)
	}
	if len(page4.Entries) != 1 {
		t.Errorf("page4 len=%d, want 1", len(page4.Entries))
	}
	if page4.HasMore {
		t.Errorf("page4.HasMore=true, want false")
	}
}

func TestListRejectsNotDir(t *testing.T) {
	dir := t.TempDir()
	f := filepath.Join(dir, "file.txt")
	if err := os.WriteFile(f, []byte("hi"), 0o644); err != nil {
		t.Fatal(err)
	}
	_, err := List(f, nil, 1, 50)
	if err == nil {
		t.Error("expected error for non-directory")
	}
}

func TestInfo(t *testing.T) {
	dir := t.TempDir()
	f := filepath.Join(dir, "test.txt")
	if err := os.WriteFile(f, []byte("hello world"), 0o644); err != nil {
		t.Fatal(err)
	}

	info, err := Info(f, nil)
	if err != nil {
		t.Fatalf("Info: %v", err)
	}
	if info.Name != "test.txt" {
		t.Errorf("Name=%q, want test.txt", info.Name)
	}
	if info.IsDir {
		t.Errorf("IsDir=true, want false")
	}
	if info.Size != 11 {
		t.Errorf("Size=%d, want 11", info.Size)
	}
}

func TestMkdir(t *testing.T) {
	dir := t.TempDir()
	newDir := filepath.Join(dir, "newdir", "nested")
	if err := Mkdir(newDir, nil); err != nil {
		t.Fatalf("Mkdir: %v", err)
	}
	info, err := os.Stat(newDir)
	if err != nil {
		t.Fatalf("stat: %v", err)
	}
	if !info.IsDir() {
		t.Error("expected dir")
	}
}

func TestMkdirDisallowed(t *testing.T) {
	dir := t.TempDir()
	err := Mkdir(filepath.Join(dir, "ok"), []string{"/tmp"})
	if err == nil {
		t.Error("expected error for disallowed path")
	}
}

func TestRename(t *testing.T) {
	dir := t.TempDir()
	f := filepath.Join(dir, "old.txt")
	if err := os.WriteFile(f, []byte("hi"), 0o644); err != nil {
		t.Fatal(err)
	}
	if err := Rename(f, "new.txt", nil); err != nil {
		t.Fatalf("Rename: %v", err)
	}
	if _, err := os.Stat(filepath.Join(dir, "new.txt")); err != nil {
		t.Errorf("new file not found: %v", err)
	}
	if _, err := os.Stat(f); err == nil {
		t.Error("old file still exists")
	}
}

func TestRenameBadName(t *testing.T) {
	dir := t.TempDir()
	f := filepath.Join(dir, "old.txt")
	if err := os.WriteFile(f, []byte("hi"), 0o644); err != nil {
		t.Fatal(err)
	}
	tests := []string{"/etc/passwd", "..", ".", "-f", ""}
	for _, name := range tests {
		err := Rename(f, name, nil)
		if err == nil {
			t.Errorf("Rename(%q): expected error", name)
		}
	}
}

func TestDelete(t *testing.T) {
	dir := t.TempDir()
	f := filepath.Join(dir, "todelete.txt")
	if err := os.WriteFile(f, []byte("hi"), 0o644); err != nil {
		t.Fatal(err)
	}
	if err := Delete(f, nil); err != nil {
		t.Fatalf("Delete: %v", err)
	}
	if _, err := os.Stat(f); err == nil {
		t.Error("file still exists after delete")
	}
}

func TestDeleteRecursively(t *testing.T) {
	dir := t.TempDir()
	subdir := filepath.Join(dir, "sub")
	if err := os.MkdirAll(subdir, 0o755); err != nil {
		t.Fatal(err)
	}
	if err := os.WriteFile(filepath.Join(subdir, "f.txt"), []byte("x"), 0o644); err != nil {
		t.Fatal(err)
	}
	if err := Delete(subdir, nil); err != nil {
		t.Fatalf("Delete: %v", err)
	}
	if _, err := os.Stat(subdir); err == nil {
		t.Error("subdir still exists")
	}
}

func TestDeleteRejectsRoot(t *testing.T) {
	err := Delete("/", nil)
	if err == nil {
		t.Error("expected error deleting root")
	}
}

func TestChmod(t *testing.T) {
	dir := t.TempDir()
	f := filepath.Join(dir, "file.txt")
	if err := os.WriteFile(f, []byte("hi"), 0o644); err != nil {
		t.Fatal(err)
	}
	if err := Chmod(f, 0o600, nil); err != nil {
		t.Fatalf("Chmod: %v", err)
	}
	info, _ := os.Stat(f)
	if info.Mode().Perm() != 0o600 {
		t.Errorf("mode=%o, want 600", info.Mode().Perm())
	}
}

func TestChown(t *testing.T) {
	dir := t.TempDir()
	f := filepath.Join(dir, "file.txt")
	if err := os.WriteFile(f, []byte("hi"), 0o644); err != nil {
		t.Fatal(err)
	}
	stat, _ := os.Stat(f)
	st := stat.Sys().(*syscall.Stat_t)
	if err := Chown(f, int(st.Uid), int(st.Gid), nil); err != nil {
		t.Fatalf("Chown: %v", err)
	}
}

func TestSearch(t *testing.T) {
	dir := t.TempDir()
	sub := filepath.Join(dir, "photos")
	if err := os.MkdirAll(sub, 0o755); err != nil {
		t.Fatal(err)
	}
	files := map[string]string{
		"myphoto.jpg":   "xxx",
		"photo_album.txt": "yyy",
		"report.pdf":     "zzz",
		"data.csv":       "aaa",
	}
	for name, content := range files {
		if err := os.WriteFile(filepath.Join(dir, name), []byte(content), 0o644); err != nil {
			t.Fatal(err)
		}
	}
	if err := os.WriteFile(filepath.Join(sub, "vacation.png"), []byte("img"), 0o644); err != nil {
		t.Fatal(err)
	}

	hits, err := Search(dir, "photo", 50, nil)
	if err != nil {
		t.Fatalf("Search: %v", err)
	}
	if len(hits) < 2 {
		t.Errorf("got %d hits, want at least 2", len(hits))
	}
}

func TestSearchLimit(t *testing.T) {
	dir := t.TempDir()
	for i := 0; i < 20; i++ {
		if err := os.WriteFile(filepath.Join(dir, "file_match_"+string(rune('a'+i))+".txt"), []byte("x"), 0o644); err != nil {
			t.Fatal(err)
		}
	}

	hits, err := Search(dir, "file_match", 5, nil)
	if err != nil {
		t.Fatalf("Search: %v", err)
	}
	if len(hits) != 5 {
		t.Errorf("got %d hits, want 5", len(hits))
	}
}

func TestValidatePathAllowed(t *testing.T) {
	dir := t.TempDir()
	f := filepath.Join(dir, "allowed.txt")
	if err := os.WriteFile(f, []byte("hi"), 0o644); err != nil {
		t.Fatal(err)
	}

	errs := []string{
		filepath.Join(dir, "..", "etc", "passwd"),
		"/etc/passwd",
		"/tmp/../../../secret",
	}
	for _, path := range errs {
		_, err := List(path, []string{dir}, 1, 50)
		if err == nil {
			t.Errorf("expected error for %q", path)
		}
	}
}