// Copyright 2020 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package postgres

import (
	"context"
	"path"
	"testing"

	"github.com/google/go-cmp/cmp"
	"github.com/google/go-cmp/cmp/cmpopts"
	"github.com/google/safehtml"
	"golang.org/x/pkgsite/internal"
	"golang.org/x/pkgsite/internal/licenses"
	"golang.org/x/pkgsite/internal/source"
	"golang.org/x/pkgsite/internal/stdlib"
	"golang.org/x/pkgsite/internal/testing/sample"
)

func TestGetUnitMeta(t *testing.T) {
	ctx, cancel := context.WithTimeout(context.Background(), testTimeout)
	defer cancel()

	defer ResetTestDB(testDB, t)

	for _, testModule := range []struct {
		module, version, packageSuffix string
		isMaster                       bool
	}{
		{"m.com", "v1.0.0", "a", false},
		{"m.com", "v1.0.1", "dir/a", false},
		{"m.com", "v1.1.0", "a/b", false},
		{"m.com", "v1.2.0-pre", "a", true},
		{"m.com", "v2.0.0+incompatible", "a", false},
		{"m.com/a", "v1.1.0", "b", false},
		{"m.com/b", "v2.0.0+incompatible", "a", true},
	} {
		pkgName := path.Base(testModule.packageSuffix)
		pkgPath := path.Join(testModule.module, testModule.packageSuffix)
		m := &internal.Module{
			LegacyModuleInfo: internal.LegacyModuleInfo{
				ModuleInfo: internal.ModuleInfo{
					CommitTime: sample.CommitTime,
					ModulePath: testModule.module,
					Version:    testModule.version,
					SourceInfo: source.NewGitHubInfo("https://"+testModule.module, "", testModule.version),
				},
			},
			LegacyPackages: []*internal.LegacyPackage{{
				Name:     pkgName,
				Path:     pkgPath,
				Licenses: sample.LicenseMetadata,
			}},
		}
		for d := pkgPath; d != "." && len(d) >= len(testModule.module); d = path.Dir(d) {
			dir := &internal.Unit{
				UnitMeta: internal.UnitMeta{
					Path:     d,
					Licenses: sample.LicenseMetadata,
				},
			}
			if d == pkgPath {
				dir.Name = pkgName
				dir.Documentation = &internal.Documentation{}
			}
			sample.AddUnit(m, dir)
		}
		if err := testDB.InsertModule(ctx, m); err != nil {
			t.Fatal(err)
		}
		requested := m.Version
		if testModule.isMaster {
			requested = internal.MasterVersion
		}
		if err := testDB.UpsertVersionMap(ctx, &internal.VersionMap{
			ModulePath:       m.ModulePath,
			RequestedVersion: requested,
			ResolvedVersion:  m.Version,
		}); err != nil {
			t.Fatal(err)
		}
	}

	for _, test := range []struct {
		name                  string
		path, module, version string
		want                  *internal.UnitMeta
	}{
		{
			name:    "known module and version",
			path:    "m.com/a",
			module:  "m.com",
			version: "v1.2.0-pre",
			want: &internal.UnitMeta{
				ModulePath: "m.com",
				Version:    "v1.2.0-pre",
				Name:       "a",
			},
		},
		{
			name:    "unknown module, known version",
			path:    "m.com/a/b",
			version: "v1.1.0",
			// The path is in two modules at v1.1.0. Prefer the longer one.
			want: &internal.UnitMeta{
				ModulePath: "m.com/a",
				Version:    "v1.1.0",
				Name:       "b",
			},
		},
		{
			name:   "known module, unknown version",
			path:   "m.com/a",
			module: "m.com",
			// Choose the latest release version.
			want: &internal.UnitMeta{
				ModulePath: "m.com",
				Version:    "v1.1.0",
			},
		},
		{
			name: "unknown module and version",
			path: "m.com/a/b",
			// Select the latest release version, longest module.
			want: &internal.UnitMeta{
				ModulePath: "m.com/a",
				Version:    "v1.1.0",
				Name:       "b",
			},
		},
		{
			name: "module",
			path: "m.com",
			// Select the latest version of the module.
			want: &internal.UnitMeta{
				ModulePath: "m.com",
				Version:    "v1.1.0",
			},
		},
		{
			name:    "longest module",
			path:    "m.com/a",
			version: "v1.1.0",
			// Prefer module m/a over module m, directory a.
			want: &internal.UnitMeta{
				ModulePath: "m.com/a",
				Version:    "v1.1.0",
			},
		},
		{
			name: "directory",
			path: "m.com/dir",
			want: &internal.UnitMeta{
				ModulePath: "m.com",
				Version:    "v1.0.1",
			},
		},
		{
			name:    "module at master version",
			path:    "m.com",
			version: "master",
			want: &internal.UnitMeta{
				ModulePath: "m.com",
				Version:    "v1.2.0-pre",
			},
		},
		{
			name:    "package at master version",
			path:    "m.com/a",
			version: "master",
			want: &internal.UnitMeta{
				ModulePath: "m.com",
				Version:    "v1.2.0-pre",
				Name:       "a",
			},
		},
		{
			name:    "incompatible module",
			path:    "m.com/b",
			version: "master",
			want: &internal.UnitMeta{
				ModulePath: "m.com/b",
				Version:    "v2.0.0+incompatible",
			},
		},
	} {
		t.Run(test.name, func(t *testing.T) {
			if test.module == "" {
				test.module = internal.UnknownModulePath
			}
			if test.version == "" {
				test.version = internal.LatestVersion
			}
			test.want = sample.UnitMeta(
				test.path,
				test.want.ModulePath,
				test.want.Version,
				test.want.Name,
				test.want.IsRedistributable,
			)
			test.want.CommitTime = sample.CommitTime
			got, err := testDB.GetUnitMeta(ctx, test.path, test.module, test.version)
			if err != nil {
				t.Fatal(err)
			}
			opts := []cmp.Option{
				cmpopts.IgnoreFields(licenses.Metadata{}, "Coverage"),
				cmp.AllowUnexported(source.Info{}, safehtml.HTML{}),
			}
			if diff := cmp.Diff(test.want, got, opts...); diff != "" {
				t.Errorf("mismatch (-want +got):\n%s", diff)
			}
		})
	}
}

func TestGetStdlibPaths(t *testing.T) {
	ctx, cancel := context.WithTimeout(context.Background(), testTimeout)
	defer cancel()
	defer ResetTestDB(testDB, t)

	// Insert two versions of some stdlib packages.
	for _, data := range []struct {
		version  string
		suffixes []string
	}{
		{
			// earlier version; should be ignored
			"v1.1.0",
			[]string{"bad/json"},
		},
		{
			"v1.2.0",
			[]string{
				"encoding/json",
				"archive/json",
				"net/http",     // no "json"
				"foo/json/moo", // "json" not the last component
				"bar/xjson",    // "json" not alone
				"baz/jsonx",    // ditto
			},
		},
	} {
		m := sample.LegacyModule(stdlib.ModulePath, data.version, data.suffixes...)
		for _, p := range m.LegacyPackages {
			p.Imports = nil
		}
		if err := testDB.InsertModule(ctx, m); err != nil {
			t.Fatal(err)
		}
	}

	got, err := testDB.GetStdlibPathsWithSuffix(ctx, "json")
	if err != nil {
		t.Fatal(err)
	}
	want := []string{"archive/json", "encoding/json"}
	if !cmp.Equal(got, want) {
		t.Errorf("got %v, want %v", got, want)
	}
}