package vpn

import (
	"context"
	"io"
	"net/netip"
	"time"

	"git.jasinco.work/wgcl/internal/logger"
	"git.jasinco.work/wgcl/internal/wg"
	protovpn "git.jasinco.work/wgcl/proto/out"
	"github.com/gin-gonic/gin"
	"google.golang.org/protobuf/encoding/protojson"
)

var wgctrl *wg.WG
var sync_cancel context.CancelFunc

func SyncWGStat(ctx context.Context) {
	for {
		select {
		case <-ctx.Done():
			return
		default:
			wgctrl.SyncStatus()
			logger.Logger.Info("sync wg status")
			time.Sleep(5 * time.Second)
		}
	}
}

func StartWG() {
	var err error
	baseip4 := netip.AddrFrom4([4]byte{172, 16, 0, 1})
	pool := wg.IPPool_Init(baseip4, 26)

	wgctrl, err = wg.WG_init("wg0", wg.NewKey(), 51823, pool)
	if err != nil {
		logger.Logger.Warn(err.Error())
		logger.Logger.Fatal("Failed init wgctrl")
	}
	ctx, cancel := context.WithCancel(context.Background())
	sync_cancel = cancel
	go SyncWGStat(ctx)
}

func StopWG() {
	logger.Logger.Info("Stopping WG")
	sync_cancel()
	wgctrl.Deinit()
}

func GETPeers(c *gin.Context) {
	resp := wgctrl.GetPeersJson()
	resp_json, err := protojson.Marshal(resp)
	if err != nil {
		c.Status(500)
		return
	}
	c.Data(200, "application/json", resp_json)
}
func NewPeer(c *gin.Context) {
	req := &protovpn.PeerReq{}
	req_json, err := io.ReadAll(c.Request.Body)
	if err != nil {
		c.Status(400)
		return
	}
	if protojson.Unmarshal(req_json, req) != nil {
		c.Status(400)
		return
	}
	wgctrl.WriteTxStart()
	defer wgctrl.WriteTxEnd()

	var ip4 *netip.Addr
	if req.HasIp4() {
		_ip4, err := netip.ParseAddr(req.GetIp4())
		ip4 = &_ip4
		if err != nil {
			c.Status(400)
			return
		}
	} else {
		_ip4, err := wgctrl.IP4Pool.Next()
		if err != nil {
			logger.Logger.Warn("ip pool exhausted")
			c.Status(500)
			return
		}
		ip4 = &_ip4
	}
	peer := wg.WGPeer_init(req.GetName(), wg.NewKey(), *ip4)
	wgctrl.AddPeer(peer)
	wgctrl.IP4Pool.Lease(*ip4)
	wgctrl.Apply()

	c.Status(200)
}

func SearchPeer(c *gin.Context) {
	if pubkey := c.Query("pubkey"); len(pubkey) > 0 {
		p, err := wgctrl.SearchPeerPubkey(pubkey)
		if p == nil {
			if err != nil {
				logger.Logger.Warn(err.Error())
			}
			c.Status(400)
			return
		}
		b, err := protojson.Marshal(p.ToPeerStatus())
		if err != nil {
			logger.Logger.Warn(err.Error())
		}
		c.Data(200, "application/json", b)
	} else {
		c.Status(400)
	}
}

func DeletePeer(c *gin.Context) {
	if pubkey := c.Query("pubkey"); len(pubkey) > 0 {
		p, err := wgctrl.SearchPeerPubkey(pubkey)
		if p == nil {
			if err != nil {
				logger.Logger.Warn(err.Error())
			}
			c.Status(400)
			return
		}
		wgctrl.WriteTxStart()
		defer wgctrl.WriteTxEnd()
		p.Disable()
		if err = wgctrl.Apply(); err != nil {
			logger.Logger.Warn("Can't apply disable peer")
		}
		wgctrl.RemovePeer(p)
		c.Status(200)
	} else {
		c.Status(400)
	}
}