package workspace

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

func TestSafePathAcceptsCleanRelativePaths(t *testing.T) {
	root := t.TempDir()

	got, err := SafePath(root, "source/manifest.json")
	if err != nil {
		t.Fatalf("SafePath: %v", err)
	}

	want := filepath.Join(root, "source", "manifest.json")
	if got != want {
		t.Fatalf("SafePath = %q, want %q", got, want)
	}
}

func TestSafePathRejectsUnsafeNames(t *testing.T) {
	root := t.TempDir()
	tests := []struct {
		name string
		path string
		want string
	}{
		{name: "empty", path: " ", want: "empty"},
		{name: "absolute", path: filepath.Join(root, "artifact.json"), want: "relative"},
		{name: "parent segment", path: "../artifact.json", want: ".."},
		{name: "embedded parent", path: "source/../artifact.json", want: ".."},
		{name: "backslash", path: `source\artifact.json`, want: "slash-separated"},
		{name: "unclean", path: "source//artifact.json", want: "clean"},
		{name: "dot", path: ".", want: ".."},
	}

	for _, tc := range tests {
		t.Run(tc.name, func(t *testing.T) {
			got, err := SafePath(root, tc.path)
			if err == nil {
				t.Fatalf("SafePath returned %q, want error", got)
			}
			if !strings.Contains(err.Error(), tc.want) {
				t.Fatalf("SafePath error = %v, want containing %q", err, tc.want)
			}
		})
	}
}

func TestSafePathRejectsEmptyRoot(t *testing.T) {
	got, err := SafePath(" ", "artifact.json")
	if err == nil {
		t.Fatalf("SafePath returned %q, want error", got)
	}
	if !strings.Contains(err.Error(), "root") {
		t.Fatalf("SafePath error = %v, want root error", err)
	}
}

func TestSafePathDoesNotPermitEscapingRoot(t *testing.T) {
	root := t.TempDir()
	for _, name := range []string{
		"..",
		"../outside.json",
		"nested/../../outside.json",
	} {
		t.Run(name, func(t *testing.T) {
			got, err := SafePath(root, name)
			if err == nil {
				t.Fatalf("SafePath returned %q, want error", got)
			}
		})
	}
}

func TestWriteJSONWritesIndentedAtomicArtifact(t *testing.T) {
	root := t.TempDir()

	err := WriteJSON(root, "source/manifest.json", map[string]any{
		"status": "succeeded",
		"count":  2,
	})
	if err != nil {
		t.Fatalf("WriteJSON: %v", err)
	}

	got := string(readFile(t, filepath.Join(root, "source", "manifest.json")))
	if !strings.HasSuffix(got, "\n") {
		t.Fatalf("expected trailing newline, got %q", got)
	}
	if !strings.Contains(got, `"status": "succeeded"`) || !strings.Contains(got, `"count": 2`) {
		t.Fatalf("unexpected JSON: %s", got)
	}
	assertNoTempFiles(t, filepath.Join(root, "source"))
}

func TestWriteBytesWritesNestedArtifact(t *testing.T) {
	root := t.TempDir()

	if err := WriteBytes(root, "chunk/chunks.json", []byte("payload")); err != nil {
		t.Fatalf("WriteBytes: %v", err)
	}

	got := string(readFile(t, filepath.Join(root, "chunk", "chunks.json")))
	if got != "payload" {
		t.Fatalf("bytes = %q, want payload", got)
	}
	assertNoTempFiles(t, filepath.Join(root, "chunk"))
}

func TestWritersRejectUnsafePaths(t *testing.T) {
	root := t.TempDir()

	if err := WriteBytes(root, "../outside.json", []byte("payload")); err == nil {
		t.Fatalf("WriteBytes accepted unsafe path")
	}
	if err := WriteJSON(root, `debug\trace.json`, map[string]string{"x": "y"}); err == nil {
		t.Fatalf("WriteJSON accepted unsafe path")
	}
	if _, err := os.Stat(filepath.Join(root, "..", "outside.json")); !os.IsNotExist(err) {
		t.Fatalf("outside path stat err = %v, want not exist", err)
	}
}

func readFile(t *testing.T, path string) []byte {
	t.Helper()
	data, err := os.ReadFile(path)
	if err != nil {
		t.Fatalf("read %q: %v", path, err)
	}
	return data
}

func assertNoTempFiles(t *testing.T, dir string) {
	t.Helper()
	entries, err := os.ReadDir(dir)
	if err != nil {
		t.Fatalf("read dir %q: %v", dir, err)
	}
	for _, entry := range entries {
		if strings.Contains(entry.Name(), ".tmp-") {
			t.Fatalf("temporary file was not cleaned up: %s", entry.Name())
		}
	}
}