// Copyright 2026 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package cloudstorage

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

	"github.com/google/go-cmp/cmp"
	"github.com/googleapis/mcp-toolbox/internal/server"
	"github.com/googleapis/mcp-toolbox/internal/sources"
	"github.com/googleapis/mcp-toolbox/internal/testutils"
)

func TestParseFromYamlCloudStorage(t *testing.T) {
	tcs := []struct {
		desc string
		in   string
		want server.SourceConfigs
	}{
		{
			desc: "basic example",
			in: `
			kind: source
			name: my-gcs
			type: cloud-storage
			project: my-project
			`,
			want: map[string]sources.SourceConfig{
				"my-gcs": Config{
					Name:    "my-gcs",
					Type:    SourceType,
					Project: "my-project",
				},
			},
		},
		{
			desc: "with allowed buckets and local roots",
			in: `
			kind: source
			name: my-gcs
			type: cloud-storage
			project: my-project
			allowedBuckets:
				- bucket1
				- bucket2
			allowedLocalRoots:
				- /var/tmp
				- /workspace
			`,
			want: map[string]sources.SourceConfig{
				"my-gcs": Config{
					Name:              "my-gcs",
					Type:              SourceType,
					Project:           "my-project",
					AllowedBuckets:    []string{"bucket1", "bucket2"},
					AllowedLocalRoots: []string{"/var/tmp", "/workspace"},
				},
			},
		},
	}
	for _, tc := range tcs {
		t.Run(tc.desc, func(t *testing.T) {
			got, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
			if err != nil {
				t.Fatalf("unable to unmarshal: %s", err)
			}
			if !cmp.Equal(tc.want, got) {
				t.Fatalf("incorrect parse: %v", cmp.Diff(tc.want, got))
			}
		})
	}
}

func TestFailParseFromYaml(t *testing.T) {
	tcs := []struct {
		desc string
		in   string
		err  string
	}{
		{
			desc: "extra field",
			in: `
			kind: source
			name: my-gcs
			type: cloud-storage
			project: my-project
			foo: bar
			`,
			err: "error unmarshaling source: unable to parse source \"my-gcs\" as \"cloud-storage\": [1:1] unknown field \"foo\"\n>  1 | foo: bar\n       ^\n   2 | name: my-gcs\n   3 | project: my-project\n   4 | type: cloud-storage",
		},
		{
			desc: "missing required field",
			in: `
			kind: source
			name: my-gcs
			type: cloud-storage
			`,
			err: "error unmarshaling source: unable to parse source \"my-gcs\" as \"cloud-storage\": Key: 'Config.Project' Error:Field validation for 'Project' failed on the 'required' tag",
		},
	}
	for _, tc := range tcs {
		t.Run(tc.desc, func(t *testing.T) {
			_, _, _, _, _, _, err := server.UnmarshalResourceConfig(context.Background(), testutils.FormatYaml(tc.in))
			if err == nil {
				t.Fatalf("expect parsing to fail")
			}
			errStr := err.Error()
			if errStr != tc.err {
				t.Fatalf("unexpected error: got %q, want %q", errStr, tc.err)
			}
		})
	}
}

func TestValidateBucket(t *testing.T) {
	tcs := []struct {
		desc           string
		allowedBuckets []string
		bucket         string
		wantErr        bool
	}{
		{
			desc:           "empty allowedBuckets succeeds",
			allowedBuckets: nil,
			bucket:         "my-bucket",
			wantErr:        false,
		},
		{
			desc:           "allowed bucket succeeds",
			allowedBuckets: []string{"my-bucket", "other-bucket"},
			bucket:         "my-bucket",
			wantErr:        false,
		},
		{
			desc:           "disallowed bucket fails",
			allowedBuckets: []string{"my-bucket", "other-bucket"},
			bucket:         "attacker-bucket",
			wantErr:        true,
		},
	}
	for _, tc := range tcs {
		t.Run(tc.desc, func(t *testing.T) {
			s := &Source{
				Config: Config{
					Name:           "my-gcs",
					AllowedBuckets: tc.allowedBuckets,
				},
			}
			err := s.validateBucket(tc.bucket)
			if (err != nil) != tc.wantErr {
				t.Fatalf("validateBucket(%q) got error: %v, wantErr: %v", tc.bucket, err, tc.wantErr)
			}
		})
	}
}

func TestValidateLocalPath(t *testing.T) {
	base := t.TempDir()

	tcs := []struct {
		desc         string
		allowedRoots []string
		path         string
		wantErr      bool
	}{
		{
			desc:         "empty allowedLocalRoots succeeds",
			allowedRoots: nil,
			path:         filepath.Join(base, "var", "tmp", "file.txt"),
			wantErr:      false,
		},
		{
			desc:         "under allowed root succeeds",
			allowedRoots: []string{filepath.Join(base, "var", "tmp"), filepath.Join(base, "workspace")},
			path:         filepath.Join(base, "workspace", "file.txt"),
			wantErr:      false,
		},
		{
			desc:         "exact match allowed root succeeds",
			allowedRoots: []string{filepath.Join(base, "var", "tmp"), filepath.Join(base, "workspace")},
			path:         filepath.Join(base, "workspace"),
			wantErr:      false,
		},
		{
			desc:         "outside allowed root fails",
			allowedRoots: []string{filepath.Join(base, "var", "tmp"), filepath.Join(base, "workspace")},
			path:         filepath.Join(base, "etc", "passwd"),
			wantErr:      true,
		},
		{
			desc:         "prefix check bypass fails (partial matching directory)",
			allowedRoots: []string{filepath.Join(base, "workspace")},
			path:         filepath.Join(base, "workspace-malicious", "file.txt"),
			wantErr:      true,
		},
		{
			desc:         "relative path is cleaned and validated",
			allowedRoots: []string{filepath.Join(base, "workspace")},
			path:         filepath.Join(base, "workspace", "..", "etc", "passwd"),
			wantErr:      true,
		},
	}
	for _, tc := range tcs {
		t.Run(tc.desc, func(t *testing.T) {
			s := &Source{
				Config: Config{
					Name:              "my-gcs",
					AllowedLocalRoots: tc.allowedRoots,
				},
			}
			err := s.validateLocalPath(tc.path)
			if (err != nil) != tc.wantErr {
				t.Fatalf("validateLocalPath(%q) got error: %v, wantErr: %v", tc.path, err, tc.wantErr)
			}
		})
	}
}