// Copyright 2009 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 linebreaks

import (
	"bytes"
	"fmt"
	"io"
	"os"
	"reflect"
	"strings"
	"testing"
)

type writerTestEntry struct {
	header *Header
	contents string
}

type writerTest struct {
	file string  // filename of expected output
	entries []*writerTestEntry
}

var writerTests = []*writerTest{
	&writerTest{
		file: "testdata/writer.tar",
		entries: []*writerTestEntry{
			&writerTestEntry{
				header: &Header{
					Name: "small.txt",
					Mode: 0640,
					Uid: 73025,
					Gid: 5000,
					Size: 5,
					Mtime: 1246508266,
					Typeflag: '0',
					Uname: "dsymonds",
					Gname: "eng",
				},
				contents: "Kilts",
			},
			&writerTestEntry{
				header: &Header{
					Name: "small2.txt",
					Mode: 0640,
					Uid: 73025,
					Gid: 5000,
					Size: 11,
					Mtime: 1245217492,
					Typeflag: '0',
					Uname: "dsymonds",
					Gname: "eng",
				},
				contents: "Google.com\n",
			},
		},
	},
	// The truncated test file was produced using these commands:
	//   dd if=/dev/zero bs=1048576 count=16384 > /tmp/16gig.txt
	//   tar -b 1 -c -f- /tmp/16gig.txt | dd bs=512 count=8 > writer-big.tar
	&writerTest{
		file: "testdata/writer-big.tar",
		entries: []*writerTestEntry{
			&writerTestEntry{
				header: &Header{
					Name: "tmp/16gig.txt",
					Mode: 0640,
					Uid: 73025,
					Gid: 5000,
					Size: 16 << 30,
					Mtime: 1254699560,
					Typeflag: '0',
					Uname: "dsymonds",
					Gname: "eng",
				},
				// no contents
			},
		},
	},
}

type untarTest struct {
	file string
	headers []*Header
}

var untarTests = []*untarTest{
	&untarTest{
		file: "testdata/gnu.tar",
		headers: []*Header{
			&Header{
				Name: "small.txt",
				Mode: 0640,
				Uid: 73025,
				Gid: 5000,
				Size: 5,
				Mtime: 1244428340,
				Typeflag: '0',
				Uname: "dsymonds",
				Gname: "eng",
			},
			&Header{
				Name: "small2.txt",
				Mode: 0640,
				Uid: 73025,
				Gid: 5000,
				Size: 11,
				Mtime: 1244436044,
				Typeflag: '0',
				Uname: "dsymonds",
				Gname: "eng",
			},
		},
	},
	&untarTest{
		file: "testdata/star.tar",
		headers: []*Header{
			&Header{
				Name: "small.txt",
				Mode: 0640,
				Uid: 73025,
				Gid: 5000,
				Size: 5,
				Mtime: 1244592783,
				Typeflag: '0',
				Uname: "dsymonds",
				Gname: "eng",
				Atime: 1244592783,
				Ctime: 1244592783,
			},
			&Header{
				Name: "small2.txt",
				Mode: 0640,
				Uid: 73025,
				Gid: 5000,
				Size: 11,
				Mtime: 1244592783,
				Typeflag: '0',
				Uname: "dsymonds",
				Gname: "eng",
				Atime: 1244592783,
				Ctime: 1244592783,
			},
		},
	},
	&untarTest{
		file: "testdata/v7.tar",
		headers: []*Header{
			&Header{
				Name: "small.txt",
				Mode: 0444,
				Uid: 73025,
				Gid: 5000,
				Size: 5,
				Mtime: 1244593104,
				Typeflag: '\x00',
			},
			&Header{
				Name: "small2.txt",
				Mode: 0444,
				Uid: 73025,
				Gid: 5000,
				Size: 11,
				Mtime: 1244593104,
				Typeflag: '\x00',
			},
		},
	},
}

var facts = map[int] string {
	0: "1",
	1: "1",
	2: "2",
	10: "3628800",
	20: "2432902008176640000",
	100: "933262154439441526816992388562667004907159682643816214685929" +
		"638952175999932299156089414639761565182862536979208272237582" +
		"51185210916864000000000000000000000000",
}

func usage() {
	fmt.Fprintf(os.Stderr,
		// TODO(gri): the 2nd string of this string list should not be indented
		"usage: godoc package [name ...]\n" +
		"	godoc -http=:6060\n")
	flag.PrintDefaults()
	os.Exit(2)
}

func TestReader(t *testing.T) {
testLoop:
	for i, test := range untarTests {
		f, err := os.Open(test.file, os.O_RDONLY, 0444)
		if err != nil {
			t.Errorf("test %d: Unexpected error: %v", i, err)
			continue
		}
		tr := NewReader(f)
		for j, header := range test.headers {
			hdr, err := tr.Next()
			if err != nil || hdr == nil {
				t.Errorf("test %d, entry %d: Didn't get entry: %v", i, j, err)
				f.Close()
				continue testLoop
			}
			if !reflect.DeepEqual(hdr, header) {
				t.Errorf("test %d, entry %d: Incorrect header:\nhave %+v\nwant %+v",
					 i, j, *hdr, *header)
			}
		}
		hdr, err := tr.Next()
		if hdr != nil || err != nil {
			t.Errorf("test %d: Unexpected entry or error: hdr=%v err=%v", i, err)
		}
		f.Close()
	}
}

// Respect line breaks in function calls.
func _() {
	f(x)
	f(x,
	  x)
	f(x,
	  x,
	)
	f(
	  x,
	  x)
	f(
	  x,
	  x,
	)
}

// Respect line breaks in function declarations.
func _(x T) {}
func _(x T,
       y T) {}
func _(x T,
       y T,
) {}
func _(
       x T,
       y T) {}
func _(
       x T,
       y T,
) {}

// Example from issue #2597.
func ManageStatus0(
	in <-chan *Status,
	req <-chan Request,
	stat chan<- *TargetInfo,
	TargetHistorySize int) {
}
    
func ManageStatus1(
	in <-chan *Status,
	req <-chan Request,
	stat chan<- *TargetInfo,
	TargetHistorySize int,
) {
}

// Example from issue #9064.
func (y *y) xerrors() error {
	_ = "xerror.test" //TODO-
	_ = []byte(`
foo bar foo bar foo bar
`) //TODO-
}

func _() {
	_ = "abc" // foo
	_ = `abc_0123456789_` // foo
}

func _() {
	_ = "abc" // foo
	_ = `abc
0123456789
` // foo
}

// There should be exactly one linebreak after this comment.