// Copyright (C) 2020 Storj Labs, Inc.
// See LICENSE for copying information.

package compensation

import (
	"io"

	"storj.io/common/strictcsv"
	"storj.io/storj/private/currency"
)

// Invoice holds the calculations for the amount required to pay to a node
// for a given pay period.
type Invoice struct {
	Period           Period             `csv:"period"`            // The payment period
	NodeID           NodeID             `csv:"node-id"`           // The node ID
	NodeCreatedAt    UTCDate            `csv:"node-created-at"`   // When the node was created
	NodeDisqualified *UTCDate           `csv:"node-disqualified"` // When and if the node was disqualified
	NodeGracefulExit *UTCDate           `csv:"node-gracefulexit"` // When and if the node finished a graceful exit
	NodeWallet       string             `csv:"node-wallet"`       // The node's wallet address
	NodeAddress      string             `csv:"node-address"`      // The node's TODO
	NodeLastIP       string             `csv:"node-last-ip"`      // The last known ip the node had
	Codes            Codes              `csv:"codes"`             // Any codes providing context to the invoice
	UsageAtRest      float64            `csv:"usage-at-rest"`     // Byte-hours provided during the payment period
	UsageGet         int64              `csv:"usage-get"`         // Number of bytes served in GET requests
	UsagePut         int64              `csv:"usage-put"`         // Number of bytes served in PUT requests
	UsageGetRepair   int64              `csv:"usage-get-repair"`  // Number of bytes served in GET_REPAIR requests
	UsagePutRepair   int64              `csv:"usage-put-repair"`  // Number of bytes served in PUT_REPAIR requests
	UsageGetAudit    int64              `csv:"usage-get-audit"`   // Number of bytes served in GET_AUDIT requests
	CompAtRest       currency.MicroUnit `csv:"comp-at-rest"`      // Compensation for usage-at-rest
	CompGet          currency.MicroUnit `csv:"comp-get"`          // Compensation for usage-get
	CompPut          currency.MicroUnit `csv:"comp-put"`          // Compensation for usage-put
	CompGetRepair    currency.MicroUnit `csv:"comp-get-repair"`   // Compensation for usage-get-repair
	CompPutRepair    currency.MicroUnit `csv:"comp-put-repair"`   // Compensation for usage-put-repair
	CompGetAudit     currency.MicroUnit `csv:"comp-get-audit"`    // Compensation for usage-get-audit
	SurgePercent     int64              `csv:"surge-percent"`     // Surge percent used to calculate compensation, or 0 if no surge
	Owed             currency.MicroUnit `csv:"owed"`              // Amount we intend to pay to the node (sum(comp-*) - held + disposed)
	Held             currency.MicroUnit `csv:"held"`              // Amount held from sum(comp-*) for this period
	Disposed         currency.MicroUnit `csv:"disposed"`          // Amount of owed that is due to graceful-exit or held period ending
	TotalHeld        currency.MicroUnit `csv:"total-held"`        // Total amount ever held from the node
	TotalDisposed    currency.MicroUnit `csv:"total-disposed"`    // Total amount ever disposed to the node
	TotalPaid        currency.MicroUnit `csv:"total-paid"`        // Total amount ever paid to the node (but not necessarily dispensed)
	TotalDistributed currency.MicroUnit `csv:"total-distributed"` // Total amount ever distributed to the node (always less than or equal to paid)
}

// MergeNodeInfo updates the fields representing the node information into the invoice.
func (invoice *Invoice) MergeNodeInfo(nodeInfo NodeInfo) error {
	if invoice.NodeID != NodeID(nodeInfo.ID) {
		return Error.New("node ID mismatch (invoice=%q nodeinfo=%q)", invoice.NodeID, nodeInfo.ID)
	}
	invoice.NodeCreatedAt = UTCDate(nodeInfo.CreatedAt)
	invoice.NodeDisqualified = (*UTCDate)(nodeInfo.Disqualified)
	invoice.NodeGracefulExit = (*UTCDate)(nodeInfo.GracefulExit)
	invoice.UsageAtRest = nodeInfo.UsageAtRest
	invoice.UsageGet = nodeInfo.UsageGet
	invoice.UsagePut = nodeInfo.UsagePut
	invoice.UsageGetRepair = nodeInfo.UsageGetRepair
	invoice.UsagePutRepair = nodeInfo.UsagePutRepair
	invoice.UsageGetAudit = nodeInfo.UsageGetAudit
	invoice.TotalHeld = nodeInfo.TotalHeld
	invoice.TotalDisposed = nodeInfo.TotalDisposed
	invoice.TotalPaid = nodeInfo.TotalPaid
	invoice.TotalDistributed = nodeInfo.TotalDistributed
	return nil
}

// MergeStatement updates the fields representing the calculation of the payment amounts
// into the invoice.
func (invoice *Invoice) MergeStatement(statement Statement) error {
	if invoice.NodeID != NodeID(statement.NodeID) {
		return Error.New("node ID mismatch (invoice=%q statement=%q)", invoice.NodeID, statement.NodeID)
	}
	invoice.Codes = statement.Codes
	invoice.CompAtRest = statement.AtRest
	invoice.CompGet = statement.Get
	invoice.CompPut = statement.Put
	invoice.CompGetRepair = statement.GetRepair
	invoice.CompPutRepair = statement.PutRepair
	invoice.CompGetAudit = statement.GetAudit
	invoice.SurgePercent = statement.SurgePercent
	invoice.Owed = statement.Owed
	invoice.Held = statement.Held
	invoice.Disposed = statement.Disposed
	return nil
}

// ReadInvoices reads a collection of Invoice values in CSV form.
func ReadInvoices(r io.Reader) ([]Invoice, error) {
	var invoices []Invoice
	if err := strictcsv.Read(r, &invoices); err != nil {
		return nil, err
	}
	return invoices, nil
}

// WriteInvoices writes a collection of Invoice values in CSV form.
func WriteInvoices(w io.Writer, invoices []Invoice) error {
	return strictcsv.Write(w, invoices)
}