package syntax

import "testing"

func TestLanguageRegistryResolve(t *testing.T) {
	r := newLanguageRegistry()

	tests := []struct {
		name string
		args struct {
			filetype string
			filename string
		}
		expected string
		wantErr  bool
	}{
		{
			name: "resolve by filetype",
			args: struct {
				filetype string
				filename string
			}{filetype: "go"},
			expected: "go",
			wantErr:  false,
		},
		{
			name: "resolve by extension",
			args: struct {
				filetype string
				filename string
			}{filename: "main.js"},
			expected: "javascript",
			wantErr:  false,
		},
		{
			name: "filetype has precedence over extension",
			args: struct {
				filetype string
				filename string
			}{filetype: "python", filename: "main.go"},
			expected: "python",
			wantErr:  false,
		},
		{
			name: "normalizes case and whitespace",
			args: struct {
				filetype string
				filename string
			}{filetype: "  Go  "},
			expected: "go",
			wantErr:  false,
		},
		{
			name: "unknown language does not resolve",
			args: struct {
				filetype string
				filename string
			}{filetype: "txt", filename: "notes.txt"},
			expected: "",
			wantErr:  false,
		},
	}

	for _, tc := range tests {
		t.Run(tc.name, func(t *testing.T) {
			res, ok, err := r.resolve(tc.args.filetype, tc.args.filename)
			if (err != nil) != tc.wantErr {
				t.Fatalf("resolve error = %v, wantErr=%v", err, tc.wantErr)
			}

			if tc.expected == "" {
				if ok || res != nil {
					t.Fatalf("expected unresolved language, got ok=%v res=%+v", ok, res)
				}
				return
			}

			if !ok || res == nil {
				t.Fatalf("expected language %q to resolve", tc.expected)
			}
			if res.id != tc.expected {
				t.Fatalf("resolved id mismatch: got %q want %q", res.id, tc.expected)
			}
		})
	}
}

func TestLanguageRegistryResolveReusesCompiledAssets(t *testing.T) {
	r := newLanguageRegistry()

	first, ok, err := r.resolve("go", "")
	if err != nil {
		t.Fatalf("resolve error: %v", err)
	}
	if !ok || first == nil {
		t.Fatalf("expected first resolution to succeed")
	}

	second, ok, err := r.resolve("golang", "")
	if err != nil {
		t.Fatalf("resolve error: %v", err)
	}
	if !ok || second == nil {
		t.Fatalf("expected second resolution to succeed")
	}

	if first != second {
		t.Fatalf("expected compiled assets to be reused for same language id")
	}
}