// +build ignore

package main

import (
	"bytes"
	"crypto/md5"
	"encoding/json"
	"flag"
	"fmt"
	"io"
	"io/ioutil"
	"log"
	"os"
	"os/exec"
	"path/filepath"
	"regexp"
	"runtime"
	"strconv"
	"strings"
	"time"
)

var (
	versionRe = regexp.MustCompile(`-[0-9]{1,3}-g[0-9a-f]{5,10}`)
	goarch    string
	goos      string
	version   string = "v1"
	// deb & rpm does not support semver so have to handle their version a little differently
	linuxPackageVersion   string = "v1"
	linuxPackageIteration string = ""
	race                  bool
	workingDir            string
	binaries              []string = []string{"grafana-server", "grafana-cli"}
)

const minGoVersion = 1.3

func main() {
	log.SetOutput(os.Stdout)
	log.SetFlags(0)

	ensureGoPath()
	readVersionFromPackageJson()

	log.Printf("Version: %s, Linux Version: %s, Package Iteration: %s\n", version, linuxPackageVersion, linuxPackageIteration)

	flag.StringVar(&goarch, "goarch", runtime.GOARCH, "GOARCH")
	flag.StringVar(&goos, "goos", runtime.GOOS, "GOOS")
	flag.BoolVar(&race, "race", race, "Use race detector")
	flag.Parse()

	if flag.NArg() == 0 {
		log.Println("Usage: go run build.go build")
		return
	}

	workingDir, _ = os.Getwd()

	for _, cmd := range flag.Args() {
		switch cmd {
		case "setup":
			setup()

		case "build":
			clean()
			for _, binary := range binaries {
				build(binary, "./pkg/cmd/"+binary, []string{})
			}

		case "test":
			test("./pkg/...")
			grunt("test")

		case "package":
			grunt("release", fmt.Sprintf("--pkgVer=%v-%v", linuxPackageVersion, linuxPackageIteration))
			createLinuxPackages()

		case "pkg-rpm":
			grunt("release")
			createRpmPackages()

		case "pkg-deb":
			grunt("release")
			createDebPackages()

		case "latest":
			makeLatestDistCopies()

		case "clean":
			clean()

		default:
			log.Fatalf("Unknown command %q", cmd)
		}
	}
}

func makeLatestDistCopies() {
	rpmIteration := "-1"
	if linuxPackageIteration != "" {
		rpmIteration = linuxPackageIteration
	}

	runError("cp", fmt.Sprintf("dist/grafana_%v-%v_amd64.deb", linuxPackageVersion, linuxPackageIteration), "dist/grafana_latest_amd64.deb")
	runError("cp", fmt.Sprintf("dist/grafana-%v-%v.x86_64.rpm", linuxPackageVersion, rpmIteration), "dist/grafana-latest-1.x86_64.rpm")
	runError("cp", fmt.Sprintf("dist/grafana-%v-%v.linux-x64.tar.gz", linuxPackageVersion, linuxPackageIteration), "dist/grafana-latest.linux-x64.tar.gz")
}

func readVersionFromPackageJson() {
	reader, err := os.Open("package.json")
	if err != nil {
		log.Fatal("Failed to open package.json")
		return
	}
	defer reader.Close()

	jsonObj := map[string]interface{}{}
	jsonParser := json.NewDecoder(reader)

	if err := jsonParser.Decode(&jsonObj); err != nil {
		log.Fatal("Failed to decode package.json")
	}

	version = jsonObj["version"].(string)
	linuxPackageVersion = version
	linuxPackageIteration = ""

	// handle pre version stuff (deb / rpm does not support semver)
	parts := strings.Split(version, "-")

	if len(parts) > 1 {
		linuxPackageVersion = parts[0]
		linuxPackageIteration = parts[1]
		if linuxPackageIteration != "" {
			// add timestamp to iteration
			linuxPackageIteration = fmt.Sprintf("%s%v", linuxPackageIteration, time.Now().Unix())
		}
		log.Println(fmt.Sprintf("Iteration %v", linuxPackageIteration))
	}
}

type linuxPackageOptions struct {
	packageType            string
	homeDir                string
	binPath                string
	serverBinPath          string
	cliBinPath             string
	configDir              string
	configFilePath         string
	ldapFilePath           string
	etcDefaultPath         string
	etcDefaultFilePath     string
	initdScriptFilePath    string
	systemdServiceFilePath string

	postinstSrc    string
	initdScriptSrc string
	defaultFileSrc string
	systemdFileSrc string

	depends []string
}

func createDebPackages() {
	createPackage(linuxPackageOptions{
		packageType:            "deb",
		homeDir:                "/usr/share/grafana",
		binPath:                "/usr/sbin",
		configDir:              "/etc/grafana",
		configFilePath:         "/etc/grafana/grafana.ini",
		ldapFilePath:           "/etc/grafana/ldap.toml",
		etcDefaultPath:         "/etc/default",
		etcDefaultFilePath:     "/etc/default/grafana-server",
		initdScriptFilePath:    "/etc/init.d/grafana-server",
		systemdServiceFilePath: "/usr/lib/systemd/system/grafana-server.service",

		postinstSrc:    "packaging/deb/control/postinst",
		initdScriptSrc: "packaging/deb/init.d/grafana-server",
		defaultFileSrc: "packaging/deb/default/grafana-server",
		systemdFileSrc: "packaging/deb/systemd/grafana-server.service",

		depends: []string{"adduser", "libfontconfig"},
	})
}

func createRpmPackages() {
	createPackage(linuxPackageOptions{
		packageType:            "rpm",
		homeDir:                "/usr/share/grafana",
		binPath:                "/usr/sbin",
		configDir:              "/etc/grafana",
		configFilePath:         "/etc/grafana/grafana.ini",
		ldapFilePath:           "/etc/grafana/ldap.toml",
		etcDefaultPath:         "/etc/sysconfig",
		etcDefaultFilePath:     "/etc/sysconfig/grafana-server",
		initdScriptFilePath:    "/etc/init.d/grafana-server",
		systemdServiceFilePath: "/usr/lib/systemd/system/grafana-server.service",

		postinstSrc:    "packaging/rpm/control/postinst",
		initdScriptSrc: "packaging/rpm/init.d/grafana-server",
		defaultFileSrc: "packaging/rpm/sysconfig/grafana-server",
		systemdFileSrc: "packaging/rpm/systemd/grafana-server.service",

		depends: []string{"initscripts", "fontconfig"},
	})
}

func createLinuxPackages() {
	createDebPackages()
	createRpmPackages()
}

func createPackage(options linuxPackageOptions) {
	packageRoot, _ := ioutil.TempDir("", "grafana-linux-pack")

	// create directories
	runPrint("mkdir", "-p", filepath.Join(packageRoot, options.homeDir))
	runPrint("mkdir", "-p", filepath.Join(packageRoot, options.configDir))
	runPrint("mkdir", "-p", filepath.Join(packageRoot, "/etc/init.d"))
	runPrint("mkdir", "-p", filepath.Join(packageRoot, options.etcDefaultPath))
	runPrint("mkdir", "-p", filepath.Join(packageRoot, "/usr/lib/systemd/system"))
	runPrint("mkdir", "-p", filepath.Join(packageRoot, "/usr/sbin"))

	// copy binary
	for _, binary := range binaries {
		runPrint("cp", "-p", filepath.Join(workingDir, "tmp/bin/"+binary), filepath.Join(packageRoot, "/usr/sbin/"+binary))
	}
	// copy init.d script
	runPrint("cp", "-p", options.initdScriptSrc, filepath.Join(packageRoot, options.initdScriptFilePath))
	// copy environment var file
	runPrint("cp", "-p", options.defaultFileSrc, filepath.Join(packageRoot, options.etcDefaultFilePath))
	// copy systemd file
	runPrint("cp", "-p", options.systemdFileSrc, filepath.Join(packageRoot, options.systemdServiceFilePath))
	// copy release files
	runPrint("cp", "-a", filepath.Join(workingDir, "tmp")+"/.", filepath.Join(packageRoot, options.homeDir))
	// remove bin path
	runPrint("rm", "-rf", filepath.Join(packageRoot, options.homeDir, "bin"))
	// copy sample ini file to /etc/grafana
	runPrint("cp", "conf/sample.ini", filepath.Join(packageRoot, options.configFilePath))
	// copy sample ldap toml config file to /etc/grafana/ldap.toml
	runPrint("cp", "conf/ldap.toml", filepath.Join(packageRoot, options.ldapFilePath))

	args := []string{
		"-s", "dir",
		"--description", "Grafana",
		"-C", packageRoot,
		"--vendor", "Grafana",
		"--url", "http://grafana.org",
		"--license", "\"Apache 2.0\"",
		"--maintainer", "contact@grafana.org",
		"--config-files", options.configFilePath,
		"--config-files", options.ldapFilePath,
		"--config-files", options.initdScriptFilePath,
		"--config-files", options.etcDefaultFilePath,
		"--config-files", options.systemdServiceFilePath,
		"--after-install", options.postinstSrc,
		"--name", "grafana",
		"--version", linuxPackageVersion,
		"-p", "./dist",
	}

	if linuxPackageIteration != "" {
		args = append(args, "--iteration", linuxPackageIteration)
	}

	// add dependenciesj
	for _, dep := range options.depends {
		args = append(args, "--depends", dep)
	}

	args = append(args, ".")

	fmt.Println("Creating package: ", options.packageType)
	runPrint("fpm", append([]string{"-t", options.packageType}, args...)...)
}

func verifyGitRepoIsClean() {
	rs, err := runError("git", "ls-files", "--modified")
	if err != nil {
		log.Fatalf("Failed to check if git tree was clean, %v, %v\n", string(rs), err)
		return
	}
	count := len(string(rs))
	if count > 0 {
		log.Fatalf("Git repository has modified files, aborting")
	}

	log.Println("Git repository is clean")
}

func ensureGoPath() {
	if os.Getenv("GOPATH") == "" {
		cwd, err := os.Getwd()
		if err != nil {
			log.Fatal(err)
		}
		gopath := filepath.Clean(filepath.Join(cwd, "../../../../"))
		log.Println("GOPATH is", gopath)
		os.Setenv("GOPATH", gopath)
	}
}

func ChangeWorkingDir(dir string) {
	os.Chdir(dir)
}

func grunt(params ...string) {
	runPrint("./node_modules/.bin/grunt", params...)
}

func setup() {
	runPrint("go", "get", "-v", "github.com/tools/godep")
	runPrint("go", "get", "-v", "github.com/blang/semver")
	runPrint("go", "get", "-v", "github.com/mattn/go-sqlite3")
	runPrint("go", "install", "-v", "github.com/mattn/go-sqlite3")
}

func test(pkg string) {
	setBuildEnv()
	runPrint("go", "test", "-short", "-timeout", "60s", pkg)
}

func build(binaryName, pkg string, tags []string) {
	binary := "./bin/" + binaryName
	if goos == "windows" {
		binary += ".exe"
	}

	rmr(binary, binary+".md5")
	args := []string{"build", "-ldflags", ldflags()}
	if len(tags) > 0 {
		args = append(args, "-tags", strings.Join(tags, ","))
	}
	if race {
		args = append(args, "-race")
	}

	args = append(args, "-o", binary)
	args = append(args, pkg)
	setBuildEnv()

	runPrint("go", "version")
	runPrint("go", args...)

	// Create an md5 checksum of the binary, to be included in the archive for
	// automatic upgrades.
	err := md5File(binary)
	if err != nil {
		log.Fatal(err)
	}
}

func ldflags() string {
	var b bytes.Buffer
	b.WriteString("-w")
	b.WriteString(fmt.Sprintf(" -X main.version=%s", version))
	b.WriteString(fmt.Sprintf(" -X main.commit=%s", getGitSha()))
	b.WriteString(fmt.Sprintf(" -X main.buildstamp=%d", buildStamp()))
	return b.String()
}

func rmr(paths ...string) {
	for _, path := range paths {
		log.Println("rm -r", path)
		os.RemoveAll(path)
	}
}

func clean() {
	rmr("bin", "Godeps/_workspace/pkg", "Godeps/_workspace/bin")
	rmr("dist")
	rmr("tmp")
	rmr(filepath.Join(os.Getenv("GOPATH"), fmt.Sprintf("pkg/%s_%s/github.com/grafana", goos, goarch)))
}

func setBuildEnv() {
	os.Setenv("GOOS", goos)
	if strings.HasPrefix(goarch, "armv") {
		os.Setenv("GOARCH", "arm")
		os.Setenv("GOARM", goarch[4:])
	} else {
		os.Setenv("GOARCH", goarch)
	}
	if goarch == "386" {
		os.Setenv("GO386", "387")
	}
	wd, err := os.Getwd()
	if err != nil {
		log.Println("Warning: can't determine current dir:", err)
		log.Println("Build might not work as expected")
	}
	os.Setenv("GOPATH", fmt.Sprintf("%s%c%s", filepath.Join(wd, "Godeps", "_workspace"), os.PathListSeparator, os.Getenv("GOPATH")))
	log.Println("GOPATH=" + os.Getenv("GOPATH"))
}

func getGitSha() string {
	v, err := runError("git", "describe", "--always", "--dirty")
	if err != nil {
		return "unknown-dev"
	}
	v = versionRe.ReplaceAllFunc(v, func(s []byte) []byte {
		s[0] = '+'
		return s
	})
	return string(v)
}

func buildStamp() int64 {
	bs, err := runError("git", "show", "-s", "--format=%ct")
	if err != nil {
		return time.Now().Unix()
	}
	s, _ := strconv.ParseInt(string(bs), 10, 64)
	return s
}

func buildArch() string {
	os := goos
	if os == "darwin" {
		os = "macosx"
	}
	return fmt.Sprintf("%s-%s", os, goarch)
}

func run(cmd string, args ...string) []byte {
	bs, err := runError(cmd, args...)
	if err != nil {
		log.Println(cmd, strings.Join(args, " "))
		log.Println(string(bs))
		log.Fatal(err)
	}
	return bytes.TrimSpace(bs)
}

func runError(cmd string, args ...string) ([]byte, error) {
	ecmd := exec.Command(cmd, args...)
	bs, err := ecmd.CombinedOutput()
	if err != nil {
		return nil, err
	}

	return bytes.TrimSpace(bs), nil
}

func runPrint(cmd string, args ...string) {
	log.Println(cmd, strings.Join(args, " "))
	ecmd := exec.Command(cmd, args...)
	ecmd.Stdout = os.Stdout
	ecmd.Stderr = os.Stderr
	err := ecmd.Run()
	if err != nil {
		log.Fatal(err)
	}
}

func md5File(file string) error {
	fd, err := os.Open(file)
	if err != nil {
		return err
	}
	defer fd.Close()

	h := md5.New()
	_, err = io.Copy(h, fd)
	if err != nil {
		return err
	}

	out, err := os.Create(file + ".md5")
	if err != nil {
		return err
	}

	_, err = fmt.Fprintf(out, "%x\n", h.Sum(nil))
	if err != nil {
		return err
	}

	return out.Close()
}