// buildTemplates converts a set of resolved, valid references into references to template objects.
func (c *AppConfig) buildTemplates(components app.ComponentReferences, environment app.Environment) ([]runtime.Object, error) {
	objects := []runtime.Object{}

	for _, ref := range components {
		tpl := ref.Input().ResolvedMatch.Template

		glog.V(4).Infof("processing template %s/%s", c.originNamespace, tpl.Name)
		for _, env := range environment.List() {
			// only set environment values that match what's expected by the template.
			if v := template.GetParameterByName(tpl, env.Name); v != nil {
				v.Value = env.Value
				v.Generate = ""
				template.AddParameter(tpl, *v)
			} else {
				return nil, fmt.Errorf("unexpected parameter name %q", env.Name)
			}
		}

		result, err := c.osclient.TemplateConfigs(c.originNamespace).Create(tpl)
		if err != nil {
			return nil, fmt.Errorf("error processing template %s/%s: %v", c.originNamespace, tpl.Name, err)
		}
		errs := runtime.DecodeList(result.Objects, kapi.Scheme)
		if len(errs) > 0 {
			err = errors.NewAggregate(errs)
			return nil, fmt.Errorf("error processing template %s/%s: %v", c.originNamespace, tpl.Name, errs)
		}
		objects = append(objects, result.Objects...)
	}
	return objects, nil
}

// injectUserVars injects user specified variables into the Template
func injectUserVars(values app.Environment, t *templateapi.Template) []error {
	var errors []error
	for param, val := range values {
		if v := template.GetParameterByName(t, param); v != nil {
			v.Value = val
			v.Generate = ""
		} else {
			errors = append(errors, fmt.Errorf("unknown parameter name %q\n", param))
		}
	}
	return errors
}

// substituteTemplateParameters injects user specified parameter values into the Template
func substituteTemplateParameters(params map[string]string, t *templateapi.Template) []error {
	var errors []error
	for name, value := range params {
		if len(name) == 0 {
			errors = append(errors, fmt.Errorf("template parameter name cannot be empty (%q)", value))
			continue
		}
		if v := template.GetParameterByName(t, name); v != nil {
			v.Value = value
			v.Generate = ""
		} else {
			errors = append(errors, fmt.Errorf("unknown parameter %q specified for template", name))
		}
	}
	return errors
}

// injectUserVars injects user specified variables into the Template
func injectUserVars(values []string, out io.Writer, t *templateapi.Template) {
	for _, keypair := range values {
		p := strings.SplitN(keypair, "=", 2)
		if len(p) != 2 {
			fmt.Fprintf(out, "invalid parameter assignment in %q: %q\n", t.Name, keypair)
			continue
		}
		if v := template.GetParameterByName(t, p[0]); v != nil {
			v.Value = p[1]
			v.Generate = ""
			template.AddParameter(t, *v)
		} else {
			fmt.Fprintf(out, "unknown parameter name %q\n", p[0])
		}
	}
}

// injectUserVars injects user specified variables into the Template
func injectUserVars(cmd *cobra.Command, t *api.Template) {
	values := kcmdutil.GetFlagStringSlice(cmd, "value")
	for _, keypair := range values {
		p := strings.SplitN(keypair, "=", 2)
		if len(p) != 2 {
			fmt.Fprintf(cmd.Out(), "invalid parameter assignment in %q: %q\n", t.Name, keypair)
			continue
		}
		if v := template.GetParameterByName(t, p[0]); v != nil {
			v.Value = p[1]
			v.Generate = ""
			template.AddParameter(t, *v)
		} else {
			fmt.Fprintf(cmd.Out(), "unknown parameter name %q\n", p[0])
		}
	}
}

// injectUserVars injects user specified variables into the Template
func injectUserVars(values []string, t *templateapi.Template) []error {
	var errors []error
	for _, keypair := range values {
		p := strings.SplitN(keypair, "=", 2)
		if len(p) != 2 {
			errors = append(errors, fmt.Errorf("invalid parameter assignment in %q: %q\n", t.Name, keypair))
		} else {
			if v := template.GetParameterByName(t, p[0]); v != nil {
				v.Value = p[1]
				v.Generate = ""
			} else {
				errors = append(errors, fmt.Errorf("unknown parameter name %q\n", p[0]))
			}
		}
	}
	return errors
}