package chaincode

import (
	"encoding/json"
	"fmt"
	"github.com/hyperledger/fabric-contract-api-go/contractapi"
	"github.com/xeipuuv/gojsonschema"
)

// SmartContract provides functions for managing an Asset
type SmartContract struct {
	contractapi.Contract
}

// Asset describes basic details of what makes up a simple asset
// Insert struct field in alphabetic order => to achieve determinism across languages
// golang keeps the order when marshal to json but doesn't order automatically


/*type Data struct {
	docType          string `json:"docType"`
	id               string `json:"id"`
	title            string `json:"title"`
	description      string `json:"description"`
	Type             string `json:"Type"`
	DOI              string `json:"DOI"`
	url              string `json:"url"`
	manifest         string `json:"manifest"`
	footprint        string `json:"footprint"`
	keywords         string `json:"keywords"`
	otherDataIdName  string `json:"otherDataIdName"`
	otherDataIdValue string `json:"otherDataIdValue"`
	fundingAgencies  string `json:"fundingAgencies"`
	acknowledgment   string `json:"acknowledgment"`
	noteForChange    string `json:"noteForChange"`
	contributor      string `json:"contributor"`
	contributor_id   string `json:"contributor_id"`
}*/


// Asset describes basic details of what makes up a simple asset
// Insert struct field in alphabetic order => to achieve determinism across languages
// golang keeps the order when marshal to json but doesn't order automatically

type Data struct {
	Contributor   string `json:"Contributor"`
	ContributorId string `json:"ContributorId"`
	ContentHash   string `json:"ContentHash"`
	Id            string `json:"Id"`
	Owners        []string `json:"Owners"`
}

// InitLedger adds a base set of Data entries to the ledger
func (s *SmartContract) InitLedger(ctx contractapi.TransactionContextInterface) error {
	dataEntries := []Data{
		{Contributor: "pepitoperes@email.com", ContributorId: "ABC123", ContentHash: "ZXCVBNM", Id: "00000", Owners: []string{"CIA", "DEA", "FBI"}},
	}

	for _, data := range dataEntries {
		assetJSON, err := json.Marshal(data)
		if err != nil {
			return err
		}

		err = ctx.GetStub().PutState(data.Id, assetJSON)
		if err != nil {
			return fmt.Errorf("failed to put to world state. %v", err)
		}
	}

	return nil
}

// GetAllAssets returns all assets found in world state
func (s *SmartContract) GetAllAssets(ctx contractapi.TransactionContextInterface) ([]*Data, error) {
	// range query with empty string for startKey and endKey does an
	// open-ended query of all assets in the chaincode namespace.
	resultsIterator, err := ctx.GetStub().GetStateByRange("", "")
	if err != nil {
		return nil, err
	}
	defer resultsIterator.Close()

	var dataSamples []*Data
	for resultsIterator.HasNext() {
		queryResponse, err := resultsIterator.Next()
		if err != nil {
			return nil, err
		}

		var data Data
		err = json.Unmarshal(queryResponse.Value, &data)
		if err != nil {
			return nil, err
		}
		dataSamples = append(dataSamples, &data)
	}

	return dataSamples, nil
}

// AssetExists returns true when asset with given ID exists in world state
func (s *SmartContract) AssetExists(ctx contractapi.TransactionContextInterface, Id string) (bool, error) {
	assetJSON, err := ctx.GetStub().GetState(Id)
	if err != nil {
		return false, fmt.Errorf("failed to read from world state: %v", err)
	}

	return assetJSON != nil, nil
}

// JSON Validation

func (s *SmartContract) validJson() (bool, error) {
	
	schemaLoader := gojsonschema.NewReferenceLoader("file:///home/ofgarzon2662/OSC-IS/fabric-samples/test-network/JsonSchemaValidationTests/Schema.json")
	documentLoader := gojsonschema.NewReferenceLoader("file:////home/ofgarzon2662/OSC-IS/fabric-samples/test-network/JsonSchemaValidationTests/testFile.json")

	result, err := gojsonschema.Validate(schemaLoader, documentLoader)

	if err != nil {
		panic(err.Error())
	}

	if result.Valid() {
		fmt.Printf("The document is valid\n")
	} else {
		fmt.Printf("The document is not valid. see errors :\n")
		for _, desc := range result.Errors() {
			fmt.Printf("- %s\n", desc)
		}
	}
	return result.Valid(), nil
}

// CreateDataSample issues a new Data Sample to the world state with given details.
func (s *SmartContract) CreateDataSample(ctx contractapi.TransactionContextInterface,
	Contributor string, ContributorId string, ContentHash string, Id string) error {

	exists, err := s.AssetExists(ctx, Id)
	if err != nil {
		return err
	}
	if exists {
		return fmt.Errorf("the asset %s already exists", Id)
	}

	//valid, err := s.validJson()
	//if err != nil {
	//	return err
	//}
	//if !valid {
	//	return fmt.Errorf("The Json file provided is not valid")
	//} else {
	data := Data{
		Contributor   :Contributor,
		ContributorId :ContributorId,
		ContentHash   :ContentHash,
		Id            :Id,
		Owners        :[]string{"DOE", "DOS", "DOJ"}}

	assetJSON, err := json.Marshal(data)
	if err != nil {
		return err
	}
	return ctx.GetStub().PutState(Id, assetJSON)
	//}	
}

// UpdateAsset updates an existing asset in the world state with provided parameters.
func (s *SmartContract) UpdateAsset(ctx contractapi.TransactionContextInterface,
	Contributor string, ContributorId string, ContentHash string, Id string) error {
	exists, err := s.AssetExists(ctx, Id)
	if err != nil {
		return err
	}
	if !exists {
		return fmt.Errorf("the asset %s does not exist", Id)
	}

	// overwriting original asset with new asset

	data := Data{
			Contributor   :Contributor,
			ContributorId :ContributorId,
			ContentHash   :ContentHash,
			Id            :Id,
			Owners        :[]string{"DOE", "DOS", "DOJ"},
	}

	assetJSON, err := json.Marshal(data)
	if err != nil {
		return err
	}

	return ctx.GetStub().PutState(Id, assetJSON)
}

func (s *SmartContract) DeleteAsset(ctx contractapi.TransactionContextInterface, Id string) error {
	exists, err := s.AssetExists(ctx, Id)
	if err != nil {
		return err
	}
	if !exists {
		return fmt.Errorf("the asset %s does not exist", Id)
	}

	return ctx.GetStub().DelState(Id)
}

func (s *SmartContract) ReadAsset(ctx contractapi.TransactionContextInterface, Id string) (*Data, error) {
	assetJSON, err := ctx.GetStub().GetState(Id)
	if err != nil {
		return nil, fmt.Errorf("failed to read from world state: %v", err)
	}
	if assetJSON == nil {
		return nil, fmt.Errorf("the asset %s does not exist", Id)
	}

	var data Data
	err = json.Unmarshal(assetJSON, &data)
	if err != nil {
		return nil, err
	}

	return &data, nil
}

// TransferAsset updates the owner field of asset with given id in world state, and returns the old owner.
func (s *SmartContract) TransferAsset(ctx contractapi.TransactionContextInterface, Id string, newOwners []string) ([]string, error) {
	data, err := s.ReadAsset(ctx, Id)
	if err != nil {
		return []string{}, err
	}

	data.Owners = newOwners

	assetJSON, err := json.Marshal(data)
	if err != nil {
		return []string{}, err
	}

	err = ctx.GetStub().PutState(Id, assetJSON)
	if err != nil {
		return []string{}, err
	}

	return data.Owners, nil
}

/*


// ReadAsset returns the asset stored in the world state with given id.
func (s *SmartContract) ReadAsset(ctx contractapi.TransactionContextInterface, id string) (*Asset, error) {
	assetJSON, err := ctx.GetStub().GetState(id)
	if err != nil {
		return nil, fmt.Errorf("failed to read from world state: %v", err)
	}
	if assetJSON == nil {
		return nil, fmt.Errorf("the asset %s does not exist", id)
	}

	var asset Asset
	err = json.Unmarshal(assetJSON, &asset)
	if err != nil {
		return nil, err
	}

	return &asset, nil
}



// TransferAsset updates the owner field of asset with given id in world state, and returns the old owner.
func (s *SmartContract) TransferAsset(ctx contractapi.TransactionContextInterface, id string, newOwner string) (string, error) {
	asset, err := s.ReadAsset(ctx, id)
	if err != nil {
		return "", err
	}

	oldOwner := asset.Owner
	asset.Owner = newOwner

	assetJSON, err := json.Marshal(asset)
	if err != nil {
		return "", err
	}

	err = ctx.GetStub().PutState(id, assetJSON)
	if err != nil {
		return "", err
	}

	return oldOwner, nil
}

// GetAllAssets returns all assets found in world state
func (s *SmartContract) GetAllAssets(ctx contractapi.TransactionContextInterface) ([]*Asset, error) {
	// range query with empty string for startKey and endKey does an
	// open-ended query of all assets in the chaincode namespace.
	resultsIterator, err := ctx.GetStub().GetStateByRange("", "")
	if err != nil {
		return nil, err
	}
	defer resultsIterator.Close()

	var assets []*Asset
	for resultsIterator.HasNext() {
		queryResponse, err := resultsIterator.Next()
		if err != nil {
			return nil, err
		}

		var asset Asset
		err = json.Unmarshal(queryResponse.Value, &asset)
		if err != nil {
			return nil, err
		}
		assets = append(assets, &asset)
	}

	return assets, nil
}
*/