package plugins

import (
	"github.com/goadesign/goa/design"
	"bytes"
	"io/ioutil"
	"github.com/goadesign/goa/goagen/codegen"
	"strings"
)

// Generate generates artifacts from goa API DSL definitions.
func Generate() (filenames []string, err error) {

	api := design.Design

	var buffer bytes.Buffer

	for mediaTypeName, mediaType := range api.MediaTypes{

		cleanMediaTypeName := strings.Replace(mediaTypeName, "application/vnd.", "", 1)
		cleanMediaTypeName = strings.Replace(cleanMediaTypeName, "+json", "", 1)
		cleanMediaTypeName = codegen.Goify(cleanMediaTypeName, true)

		if mediaType.HasAttributes() && "" != mediaType.Name() {

			writeMediaType(cleanMediaTypeName, mediaType, &buffer)
		}
	}

	ioutil.WriteFile("foo.txt", buffer.Bytes(), 0644)

	return []string{"foo.txt"}, err
}


func writeMediaType(mediaTypeName string, mediaType *design.MediaTypeDefinition, buffer *bytes.Buffer) {

	buffer.WriteString("export Class ")
	buffer.WriteString(mediaTypeName)
	buffer.WriteString("{\n")

	attributesByName := mediaType.ToObject()

	for name, attribute := range attributesByName {

		handleAttribute(name, attribute, buffer)
	}

	buffer.WriteString("}\n\n")
}

func handleAttribute(attributeName string, attributeDefinition *design.AttributeDefinition, buffer *bytes.Buffer) {

	buffer.WriteString("\t")

	buffer.WriteString(attributeName)
	buffer.WriteString(": ")

	switch attributeDefinition.Type.Kind() {

		case design.BooleanKind:

			buffer.WriteString("boolean")
			break
		case design.IntegerKind:

			buffer.WriteString("number")
			break
		case design.NumberKind:

			buffer.WriteString("number")
			break
		case design.StringKind:

			buffer.WriteString("string")
			break
		case design.DateTimeKind:

			buffer.WriteString("Date")
			break
		case design.UUIDKind:

			buffer.WriteString("string")
			break
		case design.AnyKind:

			buffer.WriteString("object")
			break
		case design.ArrayKind:

			buffer.WriteString("array???")
			break
		case design.ObjectKind:

			buffer.WriteString("ObjectKind nesting not supported")
			break
		case design.HashKind:

			buffer.WriteString("string")
			break
		case design.UserTypeKind:

			buffer.WriteString("UserTypeKind: nesting not supported")
			//return "", errors.New("Nested User Types are not supported yet.")
			break
		case design.MediaTypeKind:

			buffer.WriteString("MediaTypeKind: nesting not supported")
			//return "", errors.New("Nested Media Types are not supported yet.")
			break
	}

	buffer.WriteString(";\n")
}