chaincode_finished.go

package main

import (
	"encoding/json"
	"errors"
	"fmt"
	"strconv"
	"strings"
	"time"

	"github.com/hyperledger/fabric/core/chaincode/shim"
)

var cpPrefix = "cp:"
var accountPrefix = "acct:"

// SimpleChaincode example simple Chaincode implementation
type SimpleChaincode struct {
}

func generateCUSIPSuffix(issueDate string, days int) (string, error) {

	t, err := msToTime(issueDate)
	if err != nil {
		return "", err
	}

	maturityDate := t.AddDate(0, 0, days)
	month := int(maturityDate.Month())
	day := maturityDate.Day()

	suffix := seventhDigit[month] + eigthDigit[day]
	return suffix, nil

}

const (
	millisPerSecond     = int64(time.Second / time.Millisecond)
	nanosPerMillisecond = int64(time.Millisecond / time.Nanosecond)
)

func msToTime(ms string) (time.Time, error) {
	msInt, err := strconv.ParseInt(ms, 10, 64)
	if err != nil {
		return time.Time{}, err
	}

	return time.Unix(msInt/millisPerSecond,
		(msInt%millisPerSecond)*nanosPerMillisecond), nil
}

type Owner struct {
	Company  string `json:"company"`
	Quantity int    `json:"quantity"`
}

type CP struct {
	CUSIP     string  `json:"cusip"`
	Ticker    string  `json:"ticker"`
	Par       float64 `json:"par"`
	Qty       int     `json:"qty"`
	Discount  float64 `json:"discount"`
	Maturity  int     `json:"maturity"`
	Owners    []Owner `json:"owner"`
	Issuer    string  `json:"issuer"`
	IssueDate string  `json:"issueDate"`
}

type Account struct {
	ID          string   `json:"id"`
	Prefix      string   `json:"prefix"`
	CashBalance float64  `json:"cashBalance"`
	AssetsIds   []string `json:"assetIds"`
}

type Transaction struct {
	CUSIP       string  `json:"cusip"`
	FromCompany string  `json:"fromCompany"`
	ToCompany   string  `json:"toCompany"`
	Quantity    int     `json:"quantity"`
	Discount    float64 `json:"discount"`
}

func (t *SimpleChaincode) createAccounts(stub shim.ChaincodeStubInterface, args []string) ([]byte, error) {
	fmt.Println("Creating accounts")

	//  				0
	// "number of accounts to create"
	var err error
	numAccounts, err := strconv.Atoi(args[0])
	if err != nil {
		fmt.Println("error creating accounts with input")
		return nil, errors.New("createAccounts accepts a single integer argument")
	}
	//create a bunch of accounts
	var account Account
	counter := 1
	for counter <= numAccounts {
		var prefix string
		suffix := "000A"
		if counter < 10 {
			prefix = strconv.Itoa(counter) + "0" + suffix
		} else {
			prefix = strconv.Itoa(counter) + suffix
		}
		var assetIds []string
		account = Account{ID: "company" + strconv.Itoa(counter), Prefix: prefix, CashBalance: 10000000.0, AssetsIds: assetIds}
		accountBytes, err := json.Marshal(&account)
		if err != nil {
			fmt.Println("error creating account" + account.ID)
			return nil, errors.New("Error creating account " + account.ID)
		}
		err = stub.PutState(accountPrefix+account.ID, accountBytes)
		counter++
		fmt.Println("created account" + accountPrefix + account.ID)
	}

	fmt.Println("Accounts created")
	return nil, nil

}

func (t *SimpleChaincode) createAccount(stub shim.ChaincodeStubInterface, args []string) ([]byte, error) {
	fmt.Println("Creating account")

	// Obtain the username to associate with the account
	if len(args) != 1 {
		fmt.Println("Error obtaining username")
		return nil, errors.New("createAccount accepts a single username argument")
	}
	username := args[0]

	// Build an account object for the user
	var assetIds []string
	suffix := "000A"
	prefix := username + suffix
	var account = Account{ID: username, Prefix: prefix, CashBalance: 10000000.0, AssetsIds: assetIds}
	accountBytes, err := json.Marshal(&account)
	if err != nil {
		fmt.Println("error creating account" + account.ID)
		return nil, errors.New("Error creating account " + account.ID)
	}

	fmt.Println("Attempting to get state of any existing account for " + account.ID)
	existingBytes, err := stub.GetState(accountPrefix + account.ID)
	if err == nil {

		var company Account
		err = json.Unmarshal(existingBytes, &company)
		if err != nil {
			fmt.Println("Error unmarshalling account " + account.ID + "\n--->: " + err.Error())

			if strings.Contains(err.Error(), "unexpected end") {
				fmt.Println("No data means existing account found for " + account.ID + ", initializing account.")
				err = stub.PutState(accountPrefix+account.ID, accountBytes)

				if err == nil {
					fmt.Println("created account" + accountPrefix + account.ID)
					return nil, nil
				} else {
					fmt.Println("failed to create initialize account for " + account.ID)
					return nil, errors.New("failed to initialize an account for " + account.ID + " => " + err.Error())
				}
			} else {
				return nil, errors.New("Error unmarshalling existing account " + account.ID)
			}
		} else {
			fmt.Println("Account already exists for " + account.ID + " " + company.ID)
			return nil, errors.New("Can't reinitialize existing user " + account.ID)
		}
	} else {

		fmt.Println("No existing account found for " + account.ID + ", initializing account.")
		err = stub.PutState(accountPrefix+account.ID, accountBytes)

		if err == nil {
			fmt.Println("created account" + accountPrefix + account.ID)
			return nil, nil
		} else {
			fmt.Println("failed to create initialize account for " + account.ID)
			return nil, errors.New("failed to initialize an account for " + account.ID + " => " + err.Error())
		}

	}

}

func (t *SimpleChaincode) Init(stub shim.ChaincodeStubInterface, function string, args []string) ([]byte, error) {
	fmt.Println("Init firing. Function will be ignored: " + function)

	// Initialize the collection of commercial paper keys
	fmt.Println("Initializing paper keys collection")
	var blank []string
	blankBytes, _ := json.Marshal(&blank)
	err := stub.PutState("PaperKeys", blankBytes)
	if err != nil {
		fmt.Println("Failed to initialize paper key collection")
	}

	fmt.Println("Initialization complete")
	return nil, nil
}

func (t *SimpleChaincode) issueCommercialPaper(stub shim.ChaincodeStubInterface, args []string) ([]byte, error) {
	fmt.Println("Creating commercial paper")

	/*		0
		json
	  	{
			"ticker":  "string",
			"par": 0.00,
			"qty": 10,
			"discount": 7.5,
			"maturity": 30,
			"owners": [ // This one is not required
				{
					"company": "company1",
					"quantity": 5
				},
				{
					"company": "company3",
					"quantity": 3
				},
				{
					"company": "company4",
					"quantity": 2
				}
			],
			"issuer":"company2",
			"issueDate":"1456161763790"  (current time in milliseconds as a string)
		}
	*/
	//need one arg
	if len(args) != 1 {
		fmt.Println("error invalid arguments")
		return nil, errors.New("Incorrect number of arguments. Expecting commercial paper record")
	}

	var cp CP
	var err error
	var account Account

	fmt.Println("Unmarshalling CP")
	err = json.Unmarshal([]byte(args[0]), &cp)
	if err != nil {
		fmt.Println("error invalid paper issue")
		return nil, errors.New("Invalid commercial paper issue")
	}

	//generate the CUSIP
	//get account prefix
	fmt.Println("Getting state of - " + accountPrefix + cp.Issuer)
	accountBytes, err := stub.GetState(accountPrefix + cp.Issuer)
	if err != nil {
		fmt.Println("Error Getting state of - " + accountPrefix + cp.Issuer)
		return nil, errors.New("Error retrieving account " + cp.Issuer)
	}
	err = json.Unmarshal(accountBytes, &account)
	if err != nil {
		fmt.Println("Error Unmarshalling accountBytes")
		return nil, errors.New("Error retrieving account " + cp.Issuer)
	}

	account.AssetsIds = append(account.AssetsIds, cp.CUSIP)

	// Set the issuer to be the owner of all quantity
	var owner Owner
	owner.Company = cp.Issuer
	owner.Quantity = cp.Qty

	cp.Owners = append(cp.Owners, owner)

	suffix, err := generateCUSIPSuffix(cp.IssueDate, cp.Maturity)
	if err != nil {
		fmt.Println("Error generating cusip")
		return nil, errors.New("Error generating CUSIP")
	}

	fmt.Println("Marshalling CP bytes")
	cp.CUSIP = account.Prefix + suffix

	fmt.Println("Getting State on CP " + cp.CUSIP)
	cpRxBytes, err := stub.GetState(cpPrefix + cp.CUSIP)
	if cpRxBytes == nil {
		fmt.Println("CUSIP does not exist, creating it")
		cpBytes, err := json.Marshal(&cp)
		if err != nil {
			fmt.Println("Error marshalling cp")
			return nil, errors.New("Error issuing commercial paper")
		}
		err = stub.PutState(cpPrefix+cp.CUSIP, cpBytes)
		if err != nil {
			fmt.Println("Error issuing paper")
			return nil, errors.New("Error issuing commercial paper")
		}

		fmt.Println("Marshalling account bytes to write")
		accountBytesToWrite, err := json.Marshal(&account)
		if err != nil {
			fmt.Println("Error marshalling account")
			return nil, errors.New("Error issuing commercial paper")
		}
		err = stub.PutState(accountPrefix+cp.Issuer, accountBytesToWrite)
		if err != nil {
			fmt.Println("Error putting state on accountBytesToWrite")
			return nil, errors.New("Error issuing commercial paper")
		}

		// Update the paper keys by adding the new key
		fmt.Println("Getting Paper Keys")
		keysBytes, err := stub.GetState("PaperKeys")
		if err != nil {
			fmt.Println("Error retrieving paper keys")
			return nil, errors.New("Error retrieving paper keys")
		}
		var keys []string
		err = json.Unmarshal(keysBytes, &keys)
		if err != nil {
			fmt.Println("Error unmarshel keys")
			return nil, errors.New("Error unmarshalling paper keys ")
		}

		fmt.Println("Appending the new key to Paper Keys")
		foundKey := false
		for _, key := range keys {
			if key == cpPrefix+cp.CUSIP {
				foundKey = true
			}
		}
		if foundKey == false {
			keys = append(keys, cpPrefix+cp.CUSIP)
			keysBytesToWrite, err := json.Marshal(&keys)
			if err != nil {
				fmt.Println("Error marshalling keys")
				return nil, errors.New("Error marshalling the keys")
			}
			fmt.Println("Put state on PaperKeys")
			err = stub.PutState("PaperKeys", keysBytesToWrite)
			if err != nil {
				fmt.Println("Error writting keys back")
				return nil, errors.New("Error writing the keys back")
			}
		}

		fmt.Println("Issue commercial paper %+v\n", cp)
		return nil, nil
	} else {
		fmt.Println("CUSIP exists")

		var cprx CP
		fmt.Println("Unmarshalling CP " + cp.CUSIP)
		err = json.Unmarshal(cpRxBytes, &cprx)
		if err != nil {
			fmt.Println("Error unmarshalling cp " + cp.CUSIP)
			return nil, errors.New("Error unmarshalling cp " + cp.CUSIP)
		}

		cprx.Qty = cprx.Qty + cp.Qty

		for key, val := range cprx.Owners {
			if val.Company == cp.Issuer {
				cprx.Owners[key].Quantity += cp.Qty
				break
			}
		}

		cpWriteBytes, err := json.Marshal(&cprx)
		if err != nil {
			fmt.Println("Error marshalling cp")
			return nil, errors.New("Error issuing commercial paper")
		}
		err = stub.PutState(cpPrefix+cp.CUSIP, cpWriteBytes)
		if err != nil {
			fmt.Println("Error issuing paper")
			return nil, errors.New("Error issuing commercial paper")
		}

		fmt.Println("Updated commercial paper %+v\n", cprx)
		return nil, nil
	}
}

func GetAllCPs(stub shim.ChaincodeStubInterface) ([]CP, error) {

	var allCPs []CP

	// Get list of all the keys
	keysBytes, err := stub.GetState("PaperKeys")
	if err != nil {
		fmt.Println("Error retrieving paper keys")
		return nil, errors.New("Error retrieving paper keys")
	}
	var keys []string
	err = json.Unmarshal(keysBytes, &keys)
	if err != nil {
		fmt.Println("Error unmarshalling paper keys")
		return nil, errors.New("Error unmarshalling paper keys")
	}

	// Get all the cps
	for _, value := range keys {
		cpBytes, err := stub.GetState(value)

		var cp CP
		err = json.Unmarshal(cpBytes, &cp)
		if err != nil {
			fmt.Println("Error retrieving cp " + value)
			return nil, errors.New("Error retrieving cp " + value)
		}

		fmt.Println("Appending CP" + value)
		allCPs = append(allCPs, cp)
	}

	return allCPs, nil
}

func GetCP(cpid string, stub shim.ChaincodeStubInterface) (CP, error) {
	var cp CP

	cpBytes, err := stub.GetState(cpid)
	if err != nil {
		fmt.Println("Error retrieving cp " + cpid)
		return cp, errors.New("Error retrieving cp " + cpid)
	}

	err = json.Unmarshal(cpBytes, &cp)
	if err != nil {
		fmt.Println("Error unmarshalling cp " + cpid)
		return cp, errors.New("Error unmarshalling cp " + cpid)
	}

	return cp, nil
}

func GetCompany(companyID string, stub shim.ChaincodeStubInterface) (Account, error) {
	var company Account
	companyBytes, err := stub.GetState(accountPrefix + companyID)
	if err != nil {
		fmt.Println("Account not found " + companyID)
		return company, errors.New("Account not found " + companyID)
	}

	err = json.Unmarshal(companyBytes, &company)
	if err != nil {
		fmt.Println("Error unmarshalling account " + companyID + "\n err:" + err.Error())
		return company, errors.New("Error unmarshalling account " + companyID)
	}

	return company, nil
}

// Still working on this one
func (t *SimpleChaincode) transferPaper(stub shim.ChaincodeStubInterface, args []string) ([]byte, error) {
	fmt.Println("Transferring Paper")
	/*		0
		json
	  	{
			  "CUSIP": "",
			  "fromCompany":"",
			  "toCompany":"",
			  "quantity": 1
		}
	*/
	//need one arg
	if len(args) != 1 {
		return nil, errors.New("Incorrect number of arguments. Expecting commercial paper record")
	}

	var tr Transaction

	fmt.Println("Unmarshalling Transaction")
	err := json.Unmarshal([]byte(args[0]), &tr)
	if err != nil {
		fmt.Println("Error Unmarshalling Transaction")
		return nil, errors.New("Invalid commercial paper issue")
	}

	fmt.Println("Getting State on CP " + tr.CUSIP)
	cpBytes, err := stub.GetState(cpPrefix + tr.CUSIP)
	if err != nil {
		fmt.Println("CUSIP not found")
		return nil, errors.New("CUSIP not found " + tr.CUSIP)
	}

	var cp CP
	fmt.Println("Unmarshalling CP " + tr.CUSIP)
	err = json.Unmarshal(cpBytes, &cp)
	if err != nil {
		fmt.Println("Error unmarshalling cp " + tr.CUSIP)
		return nil, errors.New("Error unmarshalling cp " + tr.CUSIP)
	}

	var fromCompany Account
	fmt.Println("Getting State on fromCompany " + tr.FromCompany)
	fromCompanyBytes, err := stub.GetState(accountPrefix + tr.FromCompany)
	if err != nil {
		fmt.Println("Account not found " + tr.FromCompany)
		return nil, errors.New("Account not found " + tr.FromCompany)
	}

	fmt.Println("Unmarshalling FromCompany ")
	err = json.Unmarshal(fromCompanyBytes, &fromCompany)
	if err != nil {
		fmt.Println("Error unmarshalling account " + tr.FromCompany)
		return nil, errors.New("Error unmarshalling account " + tr.FromCompany)
	}

	var toCompany Account
	fmt.Println("Getting State on ToCompany " + tr.ToCompany)
	toCompanyBytes, err := stub.GetState(accountPrefix + tr.ToCompany)
	if err != nil {
		fmt.Println("Account not found " + tr.ToCompany)
		return nil, errors.New("Account not found " + tr.ToCompany)
	}

	fmt.Println("Unmarshalling tocompany")
	err = json.Unmarshal(toCompanyBytes, &toCompany)
	if err != nil {
		fmt.Println("Error unmarshalling account " + tr.ToCompany)
		return nil, errors.New("Error unmarshalling account " + tr.ToCompany)
	}

	// Check for all the possible errors
	ownerFound := false
	quantity := 0
	for _, owner := range cp.Owners {
		if owner.Company == tr.FromCompany {
			ownerFound = true
			quantity = owner.Quantity
		}
	}

	// If fromCompany doesn't own this paper
	if ownerFound == false {
		fmt.Println("The company " + tr.FromCompany + "doesn't own any of this paper")
		return nil, errors.New("The company " + tr.FromCompany + "doesn't own any of this paper")
	} else {
		fmt.Println("The FromCompany does own this paper")
	}

	// If fromCompany doesn't own enough quantity of this paper
	if quantity < tr.Quantity {
		fmt.Println("The company " + tr.FromCompany + "doesn't own enough of this paper")
		return nil, errors.New("The company " + tr.FromCompany + "doesn't own enough of this paper")
	} else {
		fmt.Println("The FromCompany owns enough of this paper")
	}

	amountToBeTransferred := float64(tr.Quantity) * cp.Par
	amountToBeTransferred -= (amountToBeTransferred) * (cp.Discount / 100.0) * (float64(cp.Maturity) / 360.0)

	// If toCompany doesn't have enough cash to buy the papers
	if toCompany.CashBalance < amountToBeTransferred {
		fmt.Println("The company " + tr.ToCompany + "doesn't have enough cash to purchase the papers")
		return nil, errors.New("The company " + tr.ToCompany + "doesn't have enough cash to purchase the papers")
	} else {
		fmt.Println("The ToCompany has enough money to be transferred for this paper")
	}

	toCompany.CashBalance -= amountToBeTransferred
	fromCompany.CashBalance += amountToBeTransferred

	toOwnerFound := false
	for key, owner := range cp.Owners {
		if owner.Company == tr.FromCompany {
			fmt.Println("Reducing Quantity from the FromCompany")
			cp.Owners[key].Quantity -= tr.Quantity
			//			owner.Quantity -= tr.Quantity
		}
		if owner.Company == tr.ToCompany {
			fmt.Println("Increasing Quantity from the ToCompany")
			toOwnerFound = true
			cp.Owners[key].Quantity += tr.Quantity
			//			owner.Quantity += tr.Quantity
		}
	}

	if toOwnerFound == false {
		var newOwner Owner
		fmt.Println("As ToOwner was not found, appending the owner to the CP")
		newOwner.Quantity = tr.Quantity
		newOwner.Company = tr.ToCompany
		cp.Owners = append(cp.Owners, newOwner)
	}

	fromCompany.AssetsIds = append(fromCompany.AssetsIds, tr.CUSIP)

	// Write everything back
	// To Company
	toCompanyBytesToWrite, err := json.Marshal(&toCompany)
	if err != nil {
		fmt.Println("Error marshalling the toCompany")
		return nil, errors.New("Error marshalling the toCompany")
	}
	fmt.Println("Put state on toCompany")
	err = stub.PutState(accountPrefix+tr.ToCompany, toCompanyBytesToWrite)
	if err != nil {
		fmt.Println("Error writing the toCompany back")
		return nil, errors.New("Error writing the toCompany back")
	}

	// From company
	fromCompanyBytesToWrite, err := json.Marshal(&fromCompany)
	if err != nil {
		fmt.Println("Error marshalling the fromCompany")
		return nil, errors.New("Error marshalling the fromCompany")
	}
	fmt.Println("Put state on fromCompany")
	err = stub.PutState(accountPrefix+tr.FromCompany, fromCompanyBytesToWrite)
	if err != nil {
		fmt.Println("Error writing the fromCompany back")
		return nil, errors.New("Error writing the fromCompany back")
	}

	// cp
	cpBytesToWrite, err := json.Marshal(&cp)
	if err != nil {
		fmt.Println("Error marshalling the cp")
		return nil, errors.New("Error marshalling the cp")
	}
	fmt.Println("Put state on CP")
	err = stub.PutState(cpPrefix+tr.CUSIP, cpBytesToWrite)
	if err != nil {
		fmt.Println("Error writing the cp back")
		return nil, errors.New("Error writing the cp back")
	}

	fmt.Println("Successfully completed Invoke")
	return nil, nil
}

func (t *SimpleChaincode) Query(stub shim.ChaincodeStubInterface, function string, args []string) ([]byte, error) {
	fmt.Println("Query running. Function: " + function)

	if function == "GetAllCPs" {
		fmt.Println("Getting all CPs")
		allCPs, err := GetAllCPs(stub)
		if err != nil {
			fmt.Println("Error from getallcps")
			return nil, err
		} else {
			allCPsBytes, err1 := json.Marshal(&allCPs)
			if err1 != nil {
				fmt.Println("Error marshalling allcps")
				return nil, err1
			}
			fmt.Println("All success, returning allcps")
			return allCPsBytes, nil
		}
	} else if function == "GetCP" {
		fmt.Println("Getting particular cp")
		cp, err := GetCP(args[0], stub)
		if err != nil {
			fmt.Println("Error Getting particular cp")
			return nil, err
		} else {
			cpBytes, err1 := json.Marshal(&cp)
			if err1 != nil {
				fmt.Println("Error marshalling the cp")
				return nil, err1
			}
			fmt.Println("All success, returning the cp")
			return cpBytes, nil
		}
	} else if function == "GetCompany" {
		fmt.Println("Getting the company")
		company, err := GetCompany(args[0], stub)
		if err != nil {
			fmt.Println("Error from getCompany")
			return nil, err
		} else {
			companyBytes, err1 := json.Marshal(&company)
			if err1 != nil {
				fmt.Println("Error marshalling the company")
				return nil, err1
			}
			fmt.Println("All success, returning the company")
			return companyBytes, nil
		}
	} else {
		fmt.Println("Generic Query call")
		bytes, err := stub.GetState(args[0])

		if err != nil {
			fmt.Println("Some error happenend: " + err.Error())
			return nil, err
		}

		fmt.Println("All success, returning from generic")
		return bytes, nil
	}
}

func (t *SimpleChaincode) Invoke(stub shim.ChaincodeStubInterface, function string, args []string) ([]byte, error) {
	fmt.Println("Invoke running. Function: " + function)

	if function == "issueCommercialPaper" {
		return t.issueCommercialPaper(stub, args)
	} else if function == "transferPaper" {
		return t.transferPaper(stub, args)
	} else if function == "createAccounts" {
		return t.createAccounts(stub, args)
	} else if function == "createAccount" {
		return t.createAccount(stub, args)
	}

	return nil, errors.New("Received unknown function invocation: " + function)
}

func main() {
	err := shim.Start(new(SimpleChaincode))
	if err != nil {
		fmt.Println("Error starting Simple chaincode: %s", err)
	}
}

//lookup tables for last two digits of CUSIP
var seventhDigit = map[int]string{
	1:  "A",
	2:  "B",
	3:  "C",
	4:  "D",
	5:  "E",
	6:  "F",
	7:  "G",
	8:  "H",
	9:  "J",
	10: "K",
	11: "L",
	12: "M",
	13: "N",
	14: "P",
	15: "Q",
	16: "R",
	17: "S",
	18: "T",
	19: "U",
	20: "V",
	21: "W",
	22: "X",
	23: "Y",
	24: "Z",
}

var eigthDigit = map[int]string{
	1:  "1",
	2:  "2",
	3:  "3",
	4:  "4",
	5:  "5",
	6:  "6",
	7:  "7",
	8:  "8",
	9:  "9",
	10: "A",
	11: "B",
	12: "C",
	13: "D",
	14: "E",
	15: "F",
	16: "G",
	17: "H",
	18: "J",
	19: "K",
	20: "L",
	21: "M",
	22: "N",
	23: "P",
	24: "Q",
	25: "R",
	26: "S",
	27: "T",
	28: "U",
	29: "V",
	30: "W",
	31: "X",
}