package regtest

import (
	"io/ioutil"
	"os"
	"path/filepath"
	"strings"
	"testing"

	"golang.org/x/tools/internal/lsp/fake"
	"golang.org/x/tools/internal/testenv"
)

func TestIssue38815(t *testing.T) {
	const needs = `
-- go.mod --
module foo

-- a.go --
package main
func f() {}
`
	const ntest = `package main
func TestZ(t *testing.T) {
	f()
}
`
	const want = `package main

import "testing"

func TestZ(t *testing.T) {
	f()
}
`

	// it was returning
	// "package main\nimport \"testing\"\npackage main..."
	runner.Run(t, needs, func(t *testing.T, env *Env) {
		env.CreateBuffer("a_test.go", ntest)
		env.SaveBuffer("a_test.go")
		got := env.Editor.BufferText("a_test.go")
		if want != got {
			t.Errorf("got\n%q, wanted\n%q", got, want)
		}
	})
}

func TestVim1(t *testing.T) {
	const vim1 = `package main

import "fmt"

var foo = 1
var bar = 2

func main() {
	fmt.Printf("This is a test %v\n", foo)
	fmt.Printf("This is another test %v\n", foo)
	fmt.Printf("This is also a test %v\n", foo)
}
`

	// The file remains unchanged, but if there are any CodeActions returned, they confuse vim.
	// Therefore check for no CodeActions
	runner.Run(t, "", func(t *testing.T, env *Env) {
		env.CreateBuffer("main.go", vim1)
		env.OrganizeImports("main.go")
		actions := env.CodeAction("main.go")
		if len(actions) > 0 {
			got := env.Editor.BufferText("main.go")
			t.Errorf("unexpected actions %#v", actions)
			if got == vim1 {
				t.Errorf("no changes")
			} else {
				t.Errorf("got\n%q", got)
				t.Errorf("was\n%q", vim1)
			}
		}
	})
}

func TestVim2(t *testing.T) {
	const vim2 = `package main

import (
	"fmt"

	"example.com/blah"

	"rubbish.com/useless"
)

func main() {
	fmt.Println(blah.Name, useless.Name)
}
`

	runner.Run(t, "", func(t *testing.T, env *Env) {
		env.CreateBuffer("main.go", vim2)
		env.OrganizeImports("main.go")
		actions := env.CodeAction("main.go")
		if len(actions) > 0 {
			t.Errorf("unexpected actions %#v", actions)
		}
	})
}

func TestGOMODCACHE(t *testing.T) {
	const proxy = `
-- example.com@v1.2.3/go.mod --
module example.com

go 1.12
-- example.com@v1.2.3/x/x.go --
package x

const X = 1
-- example.com@v1.2.3/y/y.go --
package y

const Y = 2
`
	const files = `
-- go.mod --
module mod.com

require example.com v1.2.3

-- main.go --
package main

import "example.com/x"

var _, _ = x.X, y.Y
`
	testenv.NeedsGo1Point(t, 15)

	modcache, err := ioutil.TempDir("", "TestGOMODCACHE-modcache")
	if err != nil {
		t.Fatal(err)
	}
	defer os.RemoveAll(modcache)
	editorConfig := fake.EditorConfig{Env: map[string]string{"GOMODCACHE": modcache}}
	withOptions(
		WithEditorConfig(editorConfig),
		WithProxyFiles(proxy),
	).run(t, files, func(t *testing.T, env *Env) {
		env.OpenFile("main.go")
		env.Await(env.DiagnosticAtRegexp("main.go", `y.Y`))
		env.SaveBuffer("main.go")
		env.Await(EmptyDiagnostics("main.go"))
		path, _ := env.GoToDefinition("main.go", env.RegexpSearch("main.go", `y.(Y)`))
		if !strings.HasPrefix(path, filepath.ToSlash(modcache)) {
			t.Errorf("found module dependency outside of GOMODCACHE: got %v, wanted subdir of %v", path, filepath.ToSlash(modcache))
		}
	})
}