// Copyright 2019 The Chromium OS 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 main

import (
	"errors"
	"fmt"
	"io"
	"io/ioutil"
	"os"
	"path/filepath"
	"regexp"
	"strconv"
	"strings"
	"testing"
)

func TestForwardStdOutAndStdErrAndExitCodeFromLogRusage(t *testing.T) {
	withLogRusageTestContext(t, func(ctx *testContext) {
		ctx.cmdMock = func(cmd *command, stdout io.Writer, stderr io.Writer) error {
			fmt.Fprint(stdout, "somemessage")
			fmt.Fprint(stderr, "someerror")
			return newExitCodeError(23)
		}
		exitCode := callCompiler(ctx, ctx.cfg, ctx.newCommand(gccX86_64, mainCc))
		if exitCode != 23 {
			t.Errorf("unexpected exit code. Got: %d", exitCode)
		}
		if ctx.stdoutString() != "somemessage" {
			t.Errorf("stdout was not forwarded. Got: %s", ctx.stdoutString())
		}
		if ctx.stderrString() != "someerror" {
			t.Errorf("stderr was not forwarded. Got: %s", ctx.stderrString())
		}
	})
}

func TestReportGeneralErrorsFromLogRusage(t *testing.T) {
	withLogRusageTestContext(t, func(ctx *testContext) {
		ctx.cmdMock = func(cmd *command, stdout io.Writer, stderr io.Writer) error {
			return errors.New("someerror")
		}
		stderr := ctx.mustFail(callCompiler(ctx, ctx.cfg,
			ctx.newCommand(gccX86_64, mainCc)))
		if err := verifyInternalError(stderr); err != nil {
			t.Fatal(err)
		}
		if !strings.Contains(stderr, "someerror") {
			t.Errorf("unexpected error. Got: %s", stderr)
		}
	})
}

func TestCreateDirAndFileForLogRusage(t *testing.T) {
	withLogRusageTestContext(t, func(ctx *testContext) {
		logFileName := filepath.Join(ctx.tempDir, "somedir", "rusage.log")
		ctx.env = []string{"GETRUSAGE=" + logFileName}
		ctx.must(callCompiler(ctx, ctx.cfg, ctx.newCommand(gccX86_64, mainCc)))

		if _, err := os.Stat(logFileName); err != nil {
			t.Errorf("rusage log file does not exist: %s", err)
		}
	})
}

func TestLogRusageFileContent(t *testing.T) {
	withLogRusageTestContext(t, func(ctx *testContext) {
		logFileName := filepath.Join(ctx.tempDir, "rusage.log")
		ctx.env = []string{"GETRUSAGE=" + logFileName}
		ctx.must(callCompiler(ctx, ctx.cfg, ctx.newCommand(gccX86_64, mainCc)))

		data, err := ioutil.ReadFile(logFileName)
		if err != nil {
			t.Errorf("could not read the rusage log file. Error: %s", err)
		}
		// Example output:
		// 0.100318 : 0.103412 : 0.096386 : 6508 : /tmp/compiler_wrapper036306868/x86_64-cros-linux-gnu-gcc.real : x86_64-cros-linux-gnu-gcc.real --sysroot=/tmp/compiler_wrapper036306868/usr/x86_64-cros-linux-gnu main.cc -mno-movbe
		logParts := strings.Split(string(data), " : ")
		if len(logParts) != 6 {
			t.Errorf("unexpected number of rusage log parts. Got: %s", logParts)
		}

		// First 3 numbers are times in seconds.
		for i := 0; i < 3; i++ {
			if _, err := strconv.ParseFloat(logParts[i], 64); err != nil {
				t.Errorf("unexpected value for index %d. Got: %s", i, logParts[i])
			}
		}
		// Then an int for the memory usage
		if _, err := strconv.ParseInt(logParts[3], 10, 64); err != nil {
			t.Errorf("unexpected mem usage. Got: %s", logParts[3])
		}
		// Then the full path of the compiler
		if logParts[4] != filepath.Join(ctx.tempDir, gccX86_64+".real") {
			t.Errorf("unexpected compiler path. Got: %s", logParts[4])
		}
		// Then the arguments, prefixes with the compiler basename
		if matched, _ := regexp.MatchString("x86_64-cros-linux-gnu-gcc.real --sysroot=.* main.cc", logParts[5]); !matched {
			t.Errorf("unexpected compiler args. Got: %s", logParts[5])
		}
	})
}

func TestLogRusageAppendsToFile(t *testing.T) {
	withLogRusageTestContext(t, func(ctx *testContext) {
		logFileName := filepath.Join(ctx.tempDir, "rusage.log")
		ctx.env = []string{"GETRUSAGE=" + logFileName}

		ctx.must(callCompiler(ctx, ctx.cfg, ctx.newCommand(gccX86_64, mainCc)))
		data, err := ioutil.ReadFile(logFileName)
		if err != nil {
			t.Errorf("could not read the rusage log file. Error: %s", err)
		}
		firstCallLines := strings.Split(string(data), "\n")
		if len(firstCallLines) != 2 {
			t.Errorf("unexpected number of lines. Got: %s", firstCallLines)
		}
		if firstCallLines[0] == "" {
			t.Error("first line was empty")
		}
		if firstCallLines[1] != "" {
			t.Errorf("second line was not empty. Got: %s", firstCallLines[1])
		}

		ctx.must(callCompiler(ctx, ctx.cfg, ctx.newCommand(gccX86_64, mainCc)))
		data, err = ioutil.ReadFile(logFileName)
		if err != nil {
			t.Errorf("could not read the rusage log file. Error: %s", err)
		}
		secondCallLines := strings.Split(string(data), "\n")
		if len(secondCallLines) != 3 {
			t.Errorf("unexpected number of lines. Got: %s", secondCallLines)
		}
		if secondCallLines[0] != firstCallLines[0] {
			t.Errorf("first line was changed. Got: %s", secondCallLines[0])
		}
		if secondCallLines[1] == "" {
			t.Error("second line was empty")
		}
		if secondCallLines[2] != "" {
			t.Errorf("third line was not empty. Got: %s", secondCallLines[2])
		}
	})
}

func withLogRusageTestContext(t *testing.T, work func(ctx *testContext)) {
	withTestContext(t, func(ctx *testContext) {
		// Disable comparing to the old wrapper as that uses fork + wait3
		// to calculate resource usage, and the new wrapper uses the getrusage
		// syscall.
		ctx.cfg.oldWrapperPath = ""
		ctx.env = []string{"GETRUSAGE=" + filepath.Join(ctx.tempDir, "rusage.log")}
		work(ctx)
	})
}