package terraform

import (
	"fmt"

	"github.com/hashicorp/terraform/config"
)

// smcUserVariables does all the semantic checks to verify that the
// variables given satisfy the configuration itself.
func smcUserVariables(c *config.Config, vs map[string]string) []error {
	var errs []error

	// Check that all required variables are present
	required := make(map[string]struct{})
	for k, v := range c.Variables {
		if v.Required() {
			required[k] = struct{}{}
		}
	}
	for k, _ := range vs {
		delete(required, k)
	}
	if len(required) > 0 {
		for k, _ := range required {
			errs = append(errs, fmt.Errorf(
				"Required variable not set: %s", k))
		}
	}

	// TODO(mitchellh): variables that are unknown

	return errs
}