//go:build mage

package main

import (
	"fmt"
	"os"
	"path/filepath"
	"runtime"
	"time"

	"github.com/magefile/mage/mg"
	"github.com/magefile/mage/sh"
)

var (
	Default              = Build
	binary               = "spruce"
	defaultInstallPrefix = "/usr/local"
)

// Build builds the binary.
func Build() error {
	flags := ldflags()
	return sh.Run("go", "build", "-ldflags="+flags, "-a", "-o", binary, ".")
}

// Install installs the binary to the execution path.
func Install() error {
	mg.Deps(Build)

	installPrefix := os.Getenv("SPRUCE_INSTALL_PREFIX")
	if installPrefix == "" {
		installPrefix = defaultInstallPrefix
	}

	dest := filepath.Join(installPrefix, "bin", binary)

	if err := sh.Copy(binary, dest); err != nil {
		return fmt.Errorf("unable to install %s; %w", binary, err)
	}

	return nil
}

// Clean cleans the workspace
func Clean() error {
	files := []string{binary, "cv.pdf"}

	for i := range files {
		if err := sh.Rm(files[i]); err != nil {
			return fmt.Errorf("unable to remove %s; %w", binary, err)
		}
	}

	if err := sh.Run("go", "clean", "./..."); err != nil {
		return fmt.Errorf("unable to run 'go clean'; %w", err)
	}
	return nil
}

// ldflags returns the build flags.
func ldflags() string {
	ldflagsfmt := "-s -w -X main.binaryVersion=%s -X main.gitCommit=%s -X main.goVersion=%s -X main.buildTime=%s"
	buildTime := time.Now().UTC().Format(time.RFC3339)

	return fmt.Sprintf(ldflagsfmt, version(), gitCommit(), runtime.Version(), buildTime)
}

// version returns the latest git tag using git describe.
func version() string {
	version, err := sh.Output("git", "describe", "--tags")
	if err != nil {
		version = "N/A"
	}

	return version
}

// gitCommit returns the current git commit
func gitCommit() string {
	commit, err := sh.Output("git", "rev-parse", "--short", "HEAD")
	if err != nil {
		commit = "N/A"
	}

	return commit
}