package util

import (
	"fmt"
	"net/http"
	"strings"

	"github.com/gin-gonic/gin"
	"github.com/pkg/errors"
	ctrl "sigs.k8s.io/controller-runtime"
)

// Code defines the error code type.
type Code int

// Be careful, below constants must be added to the errorDetails map.
// All code should be defined between StartMarker and EndMarker
const (
	PathNotSupported Code = iota
	InvalidArgument
	UnsupportedMediaType
	StatusInternalServerError
)

type errorDetail struct {
	ID         string
	StatusCode int
	Message    string
}

var errorDetails = map[Code]errorDetail{
	PathNotSupported:          {"PathNotSupported", http.StatusNotFound, "'%s' against '%s' is not supported"},
	InvalidArgument:           {"InvalidArgument", http.StatusBadRequest, "%s"},
	UnsupportedMediaType:      {"UnsupportedMediaType", http.StatusUnsupportedMediaType, "content type should be 'application/json' or 'application/octet-stream'"},
	StatusInternalServerError: {"StatusInternalServerError", http.StatusInternalServerError, "%s"}}

// ID returns the error ID.
func (c Code) ID() string {
	return errorDetails[c].ID
}

// StatusCode returns the http status code.
func (c Code) StatusCode() int {
	return errorDetails[c].StatusCode
}

// Message returns the detailed error message.
func (c Code) Message() string {
	return errorDetails[c].Message
}

// ConstructError returns a new OpError.
func ConstructError(ec Code, a ...interface{}) error {
	msg := ""
	// the number of keys should be equal to the number of placeholders defined in ErrorCode.Message.
	c := strings.Count(ec.Message(), "%")
	switch {
	case a == nil && c > 0 ||
		a != nil && (c != len(a) || a[0] == nil):
		{
			ctrl.Log.Error(fmt.Errorf("args '%v' do not match placeholders in the msg '%s'", a, ec.Message()),
				"invalid error message argument")
		}
	case len(a) == 0 || a[0] == nil:
		{
			msg = ec.Message()
		}
	default:
		msg = fmt.Sprintf(ec.Message(), a...)
	}
	return errors.New(msg)
}

// SetErrorAndAbort is used to abort the rest of the handlers, mostly called in middleware
func SetErrorAndAbort(c *gin.Context, code Code, msg ...interface{}) {
	// Calling abort so no handlers and middlewares will be executed.
	c.AbortWithStatusJSON(code.StatusCode(), gin.H{"error": ConstructError(code, msg...).Error()})

}

// HandleError will handle error
func HandleError(c *gin.Context, code Code, msg ...interface{}) {
	err := ConstructError(code, msg...)
	AssembleResponse(c, nil, err)
}