generators.go

package mcdata

import (
	"errors"
	"fmt"
	"os"
	"path/filepath"
	"strings"

	"github.com/ChimeraCoder/gojson"
	"github.com/hashicorp/go-multierror"
)

var (
	ErrVersionNotSupported = errors.New("version provided not supported")
)

func packageNameFromPath(p string) string {
	ps := strings.Split(p, "/")
	return ps[len(ps)-1]
}

func GenerateStructs(edition, version, dest string) error {
	dataPaths, err := LoadDataPaths()
	if err != nil {
		return err
	}
	versionedPath, exist := dataPaths.getVersionedPaths(edition, version)
	if !exist {
		return ErrVersionNotSupported
	}

	curDir, _ := os.Getwd()
	basepath := filepath.Join(curDir, SubmoduleDataPath) // Refactor to read from embeded
	outpath := filepath.Join(curDir, dest)
	if err := os.MkdirAll(outpath, 0777); err != nil {
		if !os.IsExist(err) {
			return err
		}
	}

	fmt.Printf("mcdata (%d) entities detected\n", len(versionedPath))

	var res error
	var counter int
	for datatype, datapath := range versionedPath {
		counter++
		datafilepath := filepath.Join(basepath, datapath, datatype+".json")

		datafile, err := os.Open(datafilepath)
		if err != nil {
			// "Should" never happen, since dataPath definitions will always reflect a json file
			// within its respective version. Else an error should be filed to Prismarine:
			// https://github.com/PrismarineJS/minecraft-data/issues
			multierror.Append(res, err)
			continue
		}

		structName := strings.Title(datatype)
		packageName := packageNameFromPath(outpath)
		genfile, err := gojson.Generate(datafile, gojson.ParseJson, structName, packageName, []string{"json"}, false, true)
		if err != nil {
			multierror.Append(res, err)
			continue
		}

		structFile := filepath.Join(outpath, datatype+".go")
		f, err := os.Create(structFile)
		if err != nil {
			multierror.Append(res, err)
			continue
		}
		defer f.Close()

		_, err = f.Write(genfile)
		if err != nil {
			multierror.Append(res, err)
			fmt.Printf("Failed to generate entity: (%d) %s\n", counter, datatype)
		} else {
			fmt.Printf("Generated go struct for entity: (%d) %s\n", counter, datatype)
		}
	}

	return res
}