package pain

import (
	"fmt"
	"strconv"
	"time"
)

func NewDocument(initParty string) *Document {
	return &Document{
		XmlnsXsi:  PAIN_XMLNS_XSI,
		Namespace: PAIN_XMLNS,
		Contents: &PainXML{
			GroupHeader:        NewGrpHdr(initParty),
			PaymentInformation: make([]PmtInf, 0),
		},
	}
}

func (d *Document) SetMeta(creditorName, creditorAddr1, creditorAddr2, creditorIBAN, creditorBIC,
	creditorId string, collectionDate time.Time, sequenceType string) {
	creditor := Cdtr{
		Name: creditorName,
		PostalAddress: PstlAdr{
			Country: "NL", // XXX: make customizable?
			AddressLines: []AdrLine{
				AdrLine(creditorAddr1),
				AdrLine(creditorAddr2),
			},
		},
	}
	creditorAccount := CdtrAcct{
		Id: IBAN{
			IBAN: creditorIBAN,
		},
	}
	creditorAgent := CdtrAgt{
		InstitutionId: FinInstnId{
			BIC: creditorBIC,
		},
	}
	creditorSchemeId := CdtrSchmeId{
		Id: NewPartyIdSEPA3(creditorId),
	}

	paymentInfo := PmtInf{
		//Id: set in Finalize()
		Method: "DD",
		PaymentMeta: PmtTpInf{
			ServiceLevel: Code{
				Code: "SEPA",
			},
			LocalInstrument: Code{
				Code: "CORE",
			},
			SequenceType: sequenceType,
		},
		CollectionDate:  collectionDate.Format("2006-01-02"),
		Creditor:        creditor,
		CreditorAccount: creditorAccount,
		CreditorAgent:   creditorAgent,
		SchemeId:        creditorSchemeId,
		Transactions:    make([]DrctDbtTxInf, 0),
	}
	d.Contents.PaymentInformation = append(d.Contents.PaymentInformation, paymentInfo)
}

func (d *Document) Finalize(msgId string) error {
	if len(d.Contents.PaymentInformation) == 0 {
		return fmt.Errorf("no payment information, aborting")
	}
	if len(d.Contents.PaymentInformation[0].Transactions) == 0 {
		return fmt.Errorf("no transaction information, aborting")
	}

	csum := 0.0
	d.Contents.GroupHeader.MessageId = msgId
	d.Contents.GroupHeader.Timestamp = time.Now().Format("2006-01-02T15:04:05")
	d.Contents.GroupHeader.NumTx = fmt.Sprintf("%d", len(d.Contents.PaymentInformation[0].Transactions))
	d.Contents.GroupHeader.Sum = fmt.Sprintf("%.2f", csum)
	d.Contents.PaymentInformation[0].Id = msgId

	for _, tx := range d.Contents.PaymentInformation[0].Transactions {
		flt, err := strconv.ParseFloat(tx.Amount.Value, 64)
		if err != nil {
			panic(fmt.Errorf("could not parse float from %q: %v", tx.Amount.Value, err))
		}
		csum += flt
	}
	d.Contents.GroupHeader.Sum = fmt.Sprintf("%.2f", csum)

	return d.Valid()
}

func (d *Document) AddTransaction(tx DrctDbtTxInf) error {
	if len(d.Contents.PaymentInformation) == 0 {
		return fmt.Errorf("payment information not yet initialized")
	}
	d.Contents.PaymentInformation[0].Transactions = append(d.Contents.PaymentInformation[0].Transactions, tx)

	return nil
}