// +build from_src_run

// Copyright 2013 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.

// The run program is invoked via "go run" from src/run.bash or
// src/run.bat conditionally builds and runs the cmd/api tool.
//
// TODO(bradfitz): the "conditional" condition is always true.
// We should only do this if the user has the hg codereview extension
// enabled and verifies that the go.tools subrepo is checked out with
// a suitably recently version. In prep for the cmd/api rewrite.
package main

import (
	"fmt"
	"log"
	"os"
	"os/exec"
	"path/filepath"
	"strconv"
)

var goroot string

func main() {
	log.SetFlags(0)
	goroot = os.Getenv("GOROOT") // should be set by run.{bash,bat}
	if goroot == "" {
		log.Fatal("No $GOROOT set.")
	}
	isGoDeveloper := exec.Command("hg", "pq").Run() == nil
	if !isGoDeveloper && !forceAPICheck() {
		fmt.Println("Skipping cmd/api checks; hg codereview extension not available and GO_FORCE_API_CHECK not set")
		return
	}

	out, err := exec.Command("go", "install", "--tags=api_tool", "cmd/api").CombinedOutput()
	if err != nil {
		log.Fatalf("Error installing cmd/api: %v\n%s", err, out)
	}
	out, err = exec.Command("go", "tool", "api",
		"-c", file("go1", "go1.1"),
		"-next", file("next"),
		"-except", file("except")).CombinedOutput()
	if err != nil {
		log.Fatalf("Error running API checker: %v\n%s", err, out)
	}
}

// file expands s to $GOROOT/api/s.txt.
// If there are more than 1, they're comma-separated.
func file(s ...string) string {
	if len(s) > 1 {
		return file(s[0]) + "," + file(s[1:]...)
	}
	return filepath.Join(goroot, "api", s[0]+".txt")
}

// GO_FORCE_API_CHECK is set by builders.
func forceAPICheck() bool {
	v, _ := strconv.ParseBool(os.Getenv("GO_FORCE_API_CHECK"))
	return v
}