af83/edwig

package model

type CodeIndex struct {
    byCode       map[Code]ModelId
    byIdentifier map[ModelId]Codes
}

func NewCodeIndex() *CodeIndex {
    return &CodeIndex{
        byCode:       make(map[Code]ModelId),
        byIdentifier: make(map[ModelId]Codes),
    }
}

func (index *CodeIndex) Index(model ModelInstance) {
    currentIndexable, ok := index.byIdentifier[model.modelId()]
    if ok {
        for indexedCodeSpace, indexedCode := range currentIndexable {
            modelCode, ok := model.Code(indexedCodeSpace)
            if !ok || modelCode.Value() != indexedCode.Value() {
                delete(index.byCode, indexedCode)
            }
        }
    }

    if index.byIdentifier[model.modelId()] == nil {
        index.byIdentifier[model.modelId()] = make(Codes)
    }

    for _, code := range model.Codes() {
        index.byCode[code] = model.modelId()
        index.byIdentifier[model.modelId()][code.CodeSpace()] = code
    }
}

func (index *CodeIndex) Find(code Code) (ModelId, bool) {
    modelId, ok := index.byCode[code]
    return modelId, ok
}

func (index *CodeIndex) Delete(modelId ModelId) {
    currentIndexable, ok := index.byIdentifier[modelId]
    if !ok {
        return
    }

    for _, code := range currentIndexable {
        delete(index.byCode, code)
    }
    delete(index.byIdentifier, modelId)
}