package tunnelbroker

import (
	`fmt`
	`net`
	`strings`

	`github.com/go-resty/resty/v2`
	"r00t2.io/clientinfo/server"
)

// Has48 returns true if this Tunnel has a /48 assigned.
func (t *Tunnel) Has48() (has48 bool) {

	if t.Routed48 != nil {
		has48 = true
	}

	return
}

/*
	Update checks the current (or explicit) client IPv4 address, compares it against the Tunnel's configuration,
	and updates itself on change.
*/
func (t *Tunnel) Update() (updated bool, err error) {

	var myInfo *server.R00tInfo
	var resp *resty.Response
	var req *resty.Request
	var targetIp net.IP
	var respStrs []string

	if t.TunCfg.ExplicitAddr != nil {
		targetIp = *t.TunCfg.ExplicitAddr
	} else {
		// Fetch the current client IP.
		// Teeechnically we don't need to do this, as it by default uses client IP, but we wanna be as considerate as we can.
		req = t.client.R()
		// Force the response to JSON; because we pass "Linux" in the UA, it thinks it's graphical...
		req.SetHeader("Accept", "application/json")
		req.SetResult(&myInfo)

		if resp, err = req.Get(wanIpUrl); err != nil {
			return
		}
		if !resp.IsSuccess() {
			err = respToErr(resp)
			return
		}
		targetIp = myInfo.IP
	}

	if !t.ClientIPv4.Equal(targetIp) {
		// It's different, so update.
		req = t.client.R()
		req.SetBasicAuth(*t.TunCfg.Username, t.TunCfg.UpdateKey)
		req.SetQueryParam(updateTidParam, fmt.Sprintf("%d", t.TunCfg.TunnelID))
		req.SetQueryParam(updateIpParam, targetIp.To4().String())

		if resp, err = req.Get(updateBaseUrl); err != nil {
			return
		}
		if !resp.IsSuccess() {
			err = respToErr(resp)
			return
		}
		respStrs = strings.Fields(resp.String())
		if respStrs == nil || len(respStrs) == 0 {
			// I... don't know what would result in this, but let's assume it succeeded.
			updated = true
			return
		}
		switch len(respStrs) {
		case 1:
			if respStrs[0] == "abuse" {
				err = ErrHERateLimit
				return
			}
		case 2:
			switch respStrs[0] {
			case "nochg":
				// No update; existing value is the same
				return
			case "good":
				switch respStrs[1] {
				case "127.0.0.1":
					// If the second returned word is "127.0.0.1", it's a "soft fail".
					// This tends to happen if the specified address is in RFC 1918,
					// or RFC 5737, or 66.220.2.74 can't ping the address, etc.
					err = ErrHEInvalid
					return
				case targetIp.To4().String():
					updated = true
					return
				}
			}
		}
	}

	return
}