package config

import (
	"encoding/json"
	"errors"
	"flag"
	"fmt"
	"io/ioutil"
	"log"
	"os"
	"path/filepath"
	"strings"
)

var RootDir string
var Config Config_

func setFlags(printHelp *bool) {
	flag.BoolVar(printHelp, "help", false, "Print this help message.")
	flag.StringVar(&Config.LAddr, "laddr", Config.LAddr, "Listen address. (0.0.0.0:0 means any interface, any port)")
	flag.StringVar(&Config.SeedNode, "seed", Config.SeedNode, "Address of seed node")
}

func ParseFlags() {
	RootDir = os.Getenv("TMROOT")
	if RootDir == "" {
		RootDir = os.Getenv("HOME") + "/.tendermint"
	}
	configFile := RootDir + "/config.json"

	// try to read configuration. if missing, write default
	configBytes, err := ioutil.ReadFile(configFile)
	if err != nil {
		defaultConfig.write(configFile)
		fmt.Println("Config file written to config.json. Please edit & run again")
		os.Exit(1)
		return
	}

	// try to parse configuration. on error, die
	Config = Config_{}
	err = json.Unmarshal(configBytes, &Config)
	if err != nil {
		log.Panicf("Invalid configuration file %s: %v", configFile, err)
	}
	err = Config.validate()
	if err != nil {
		log.Panicf("Invalid configuration file %s: %v", configFile, err)
	}

	// try to parse arg flags, which can override file configuration.
	var printHelp bool
	setFlags(&printHelp)
	flag.Parse()
	if printHelp {
		flag.PrintDefaults()
		os.Exit(0)
	}
}

//-----------------------------------------------------------------------------j
// Default configuration

var defaultConfig = Config_{
	Network:  "tendermint_testnet0",
	LAddr:    "0.0.0.0:0",
	SeedNode: "",
	Db: DbConfig{
		Type: "level",
		Dir:  RootDir + "/data",
	},
	Alert: AlertConfig{},
	SMTP:  SMTPConfig{},
	RPC: RPCConfig{
		HTTPPort: 8888,
	},
}

//-----------------------------------------------------------------------------j
// Configuration types

type Config_ struct {
	Network  string
	LAddr    string
	SeedNode string
	Db       DbConfig
	Alert    AlertConfig
	SMTP     SMTPConfig
	RPC      RPCConfig
}

type DbConfig struct {
	Type string
	Dir  string
}

type AlertConfig struct {
	MinInterval int

	TwilioSid   string
	TwilioToken string
	TwilioFrom  string
	TwilioTo    string

	EmailRecipients []string
}

type SMTPConfig struct {
	User     string
	Password string
	Host     string
	Port     uint
}

type RPCConfig struct {
	HTTPPort uint
}

//-----------------------------------------------------------------------------j

func (cfg *Config_) validate() error {
	if cfg.Network == "" {
		cfg.Network = defaultConfig.Network
	}
	if cfg.LAddr == "" {
		cfg.LAddr = defaultConfig.LAddr
	}
	if cfg.SeedNode == "" {
		cfg.SeedNode = defaultConfig.SeedNode
	}
	if cfg.Db.Type == "" {
		return errors.New("Db.Type must be set")
	}
	return nil
}

func (cfg *Config_) bytes() []byte {
	configBytes, err := json.MarshalIndent(cfg, "", "\t")
	if err != nil {
		panic(err)
	}
	return configBytes
}

func (cfg *Config_) write(configFile string) {
	if strings.Index(configFile, "/") != -1 {
		err := os.MkdirAll(filepath.Dir(configFile), 0700)
		if err != nil {
			panic(err)
		}
	}
	err := ioutil.WriteFile(configFile, cfg.bytes(), 0600)
	if err != nil {
		panic(err)
	}
}