// Package helpers provides useful helper structures for KermaGo
package helpers

import (
	"fmt"
	"os"
	"strconv"
	"strings"
)

const (
	ipAddress        = "3.126.74.45"
	port             = 18018
	connTimeout      = 10
	storeBaseDir     = "/var/local/badkerma"
	peerListStore    = "peers.json"
	blockStore       = "blocks.json"
	transactionStore = "transactions.json"
	privateKeyFile   = "private.pem"
	listenAddr       = "0.0.0.0"
	initialPeerList  = ""
)

/*
A Config is a helper used for storing and obtaining the application configuration.
Supported configuration includes:
- IPAddress
- Port
- ListenAddr - address to listen on
- ConnTimeout - timeout for the client connections
- PeerListStore - filename for the peer list store
- BlockStore - filename for the blockchain store
- TransactionStore - filename for the transaction store
- PrivateKeyFile - filename for the private key
- InitialPeerList - initial peer list for building up
*/
type Config struct {
	IPAddress        string
	Port             int
	PeerListStore    string
	ConnTimeout      int
	PrivateKeyFile   string
	BlockStore       string
	TransactionStore string
	ListenAddr       string
	InitialPeerList  string
}

/*
Construct fetches the configuration from the KERMA_* environment variables or sets sensible defaults
*/
func (c *Config) Construct() {
	c.IPAddress = ipAddress
	c.Port = port
	c.PeerListStore = peerListStore
	c.ConnTimeout = connTimeout
	c.PrivateKeyFile = privateKeyFile
	c.BlockStore = blockStore
	c.TransactionStore = transactionStore
	c.InitialPeerList = initialPeerList

	baseDir := storeBaseDir

	if os.Getenv("KERMA_IP_ADDR") != "" {
		c.IPAddress = os.Getenv("KERMA_IP_ADDR")
	}
	if os.Getenv("KERMA_PORT") != "" {
		c.Port, _ = strconv.Atoi(os.Getenv("KERMA_PORT"))
	}
	if os.Getenv("KERMA_CONN_TIMEOUT") != "" {
		c.ConnTimeout, _ = strconv.Atoi(os.Getenv("KERMA_CONN_TIMEOUT"))
	}
	if os.Getenv("KERMA_INITIAL_PEER_LIST") != "" {
		c.InitialPeerList = os.Getenv("KERMA_INITIAL_PEER_LIST")
	}
	if os.Getenv("KERMA_STORE_BASE_DIR") != "" {
		baseDir = os.Getenv("KERMA_STORE_BASE_DIR")
		baseDir = strings.TrimSuffix(baseDir, "/")
	}
	if os.Getenv("KERMA_PEER_LIST_STORE") != "" {
		c.PeerListStore = os.Getenv("KERMA_PEER_LIST_STORE")
	}
	if os.Getenv("KERMA_BLOCK_STORE") != "" {
		c.BlockStore = os.Getenv("KERMA_BLOCK_STORE")
	}
	if os.Getenv("KERMA_TRANSACTION_STORE") != "" {
		c.TransactionStore = os.Getenv("KERMA_TRANSACTION_STORE")
	}
	if os.Getenv("KERMA_PRIVATE_KEY_FILE") != "" {
		c.PrivateKeyFile = os.Getenv("KERMA_PRIVATE_KEY_FILE")
	}

	c.PeerListStore = baseDir + "/" + c.PeerListStore
	c.BlockStore = baseDir + "/" + c.BlockStore
	c.TransactionStore = baseDir + "/" + c.TransactionStore
	c.PrivateKeyFile = baseDir + "/" + c.PrivateKeyFile
	c.ListenAddr = listenAddr + ":" + fmt.Sprint(c.Port)
}