// Copyright 2022 Princess B33f Heavy Industries / Dave Shanley
// SPDX-License-Identifier: MIT

package v2

import low "github.com/pb33f/libopenapi/datamodel/low/v2"

// ParameterDefinitions is a high-level representation of a Swagger / OpenAPI 2 Parameters Definitions object
// that is backed by a low-level one.
//
// ParameterDefinitions holds parameters to be reused across operations. Parameter definitions can be
// referenced to the ones defined here. It does not define global operation parameters
//   - https://swagger.io/specification/v2/#parametersDefinitionsObject
type ParameterDefinitions struct {
	Definitions map[string]*Parameter
	low         *low.ParameterDefinitions
}

// NewParametersDefinitions creates a new instance of a high-level ParameterDefinitions, from a low-level one.
// Every parameter is extracted asynchronously due to the potential depth
func NewParametersDefinitions(parametersDefinitions *low.ParameterDefinitions) *ParameterDefinitions {
	pd := new(ParameterDefinitions)
	pd.low = parametersDefinitions
	params := make(map[string]*Parameter)
	var buildParam = func(name string, param *low.Parameter, rChan chan<- asyncResult[*Parameter]) {
		rChan <- asyncResult[*Parameter]{
			key:    name,
			result: NewParameter(param),
		}
	}
	resChan := make(chan asyncResult[*Parameter])
	for k := range parametersDefinitions.Definitions {
		go buildParam(k.Value, parametersDefinitions.Definitions[k].Value, resChan)
	}
	totalParams := len(parametersDefinitions.Definitions)
	completedParams := 0
	for completedParams < totalParams {
		select {
		case r := <-resChan:
			completedParams++
			params[r.key] = r.result
		}
	}
	pd.Definitions = params
	return pd
}

// GoLow returns the low-level ParameterDefinitions instance that backs the low-level one.
func (p *ParameterDefinitions) GoLow() *low.ParameterDefinitions {
	return p.low
}