package server

import (
	"context"
	"fmt"
	"net/http"

	"github.com/a-h/templ"
	"github.com/go-playground/validator/v10"

	"gopics.develent.net/internal/components"
)

// Extract form and validate fields
func (srv *server) bindAndValidate(r *http.Request, form any) (map[string]string, error) {

	err := r.ParseForm()
	if err != nil {
		return nil, err
	}

	err = srv.formDecoder.Decode(form, r.PostForm)
	if err != nil {
		return nil, err
	}

	err = srv.validate.Struct(form)
	if err != nil {
		ve, ok := err.(validator.ValidationErrors)
		srv.logger.Info("BnV Validation", "ok", ok, "ve", ve)
		if ok {
			return mapValidationErrors(ve), nil // validation failed
		}
		return nil, err // something else went wrong

	}

	return nil, nil // valid
}

// Render TEMPL pages
func (srv *server) RenderPage(w http.ResponseWriter, r *http.Request, status int, page templ.Component, title string) {
	w.WriteHeader(status)
	flash := srv.sessionManager.PopString(r.Context(), "flash")
	components.Base(page, title, flash).Render(r.Context(), w)
}

// Inject flash messages into context
func (srv *server) PutFlash(ctx context.Context, msg string) {
	srv.sessionManager.Put(ctx, "flash", msg)
}

// Pop flash messages from context
func (srv *server) PopFlash(ctx context.Context) string {
	srv.logger.Info("Pre-Pop", "flash", srv.sessionManager.GetString(ctx, "flash"))
	flash := srv.sessionManager.PopString(ctx, "flash")
	srv.logger.Info("Post-Pop", "flash", srv.sessionManager.GetString(ctx, "flash"))
	return flash
}

// Map validator errors to user presentable errors
func mapValidationErrors(errs validator.ValidationErrors) map[string]string {
	errors := make(map[string]string)
	for _, fe := range errs {
		field := fe.Field()
		tag := fe.Tag()
		var msg string

		switch tag {
		case "required":
			msg = fmt.Sprintf("%s is required", field)
		case "email":
			msg = "Invalid email format"
		case "gte":
			msg = fmt.Sprintf("%s must be %s or greater", field, fe.Param())
		default:
			msg = fmt.Sprintf("%s is not valid", field)
		}
		errors[field] = msg
	}

	return errors
}