package cmd

import (
	"bytes"
	"fmt"
	"io"
	"log"
	"net/http"

	"github.com/gorilla/websocket"
	"github.com/spf13/cobra"
)

type TunnelRequest struct {
	ID      string            `json:"id"`
	Method  string            `json:"method"`
	URL     string            `json:"url"`
	Headers map[string]string `json:"headers"`
	Body    []byte            `json:"body"`
}

type TunnelResponse struct {
	ID         string            `json:"id"`
	StatusCode int               `json:"status_code"`
	Headers    map[string]string `json:"headers"`
	Body       []byte            `json:"body"`
}

var serverAddr string

var linkCmd = &cobra.Command{
	Use:   "link <vhost_location> <local_port>",
	Short: "Create a tunnel link",
	Args:  cobra.ExactArgs(2),
	Run: func(cmd *cobra.Command, args []string) {
		vhostLoc := args[0]
		localPort := args[1]

		fmt.Printf("Creating tunnel: %s -> localhost:%s\n", vhostLoc, localPort)

		if err := startTunnel(vhostLoc, localPort); err != nil {
			log.Fatal("Failed to start tunnel:", err)
		}
	},
}

func init() {
	linkCmd.Flags().StringVarP(&serverAddr, "server", "s", "localhost:8080", "Conduit server address")
}

func startTunnel(vhost, localPort string) error {
	// Connect to WebSocket
	wsURL := fmt.Sprintf("ws://%s/_conduit/tunnel?vhost=%s", serverAddr, vhost)
	conn, _, err := websocket.DefaultDialer.Dial(wsURL, nil)
	if err != nil {
		return fmt.Errorf("failed to connect: %v", err)
	}
	defer conn.Close()

	fmt.Printf("Tunnel active! %s.example.com -> localhost:%s\n", vhost, localPort)

	// Handle incoming requests
	for {
		var req TunnelRequest
		if err := conn.ReadJSON(&req); err != nil {
			log.Printf("Error reading request: %v", err)
			break
		}

		go handleTunnelRequest(conn, &req, localPort)
	}

	return nil
}

func handleTunnelRequest(conn *websocket.Conn, req *TunnelRequest, localPort string) {
	// Make request to local service
	localURL := fmt.Sprintf("http://localhost:%s%s", localPort, req.URL)

	httpReq, err := http.NewRequest(req.Method, localURL, bytes.NewReader(req.Body))
	if err != nil {
		sendErrorResponse(conn, req.ID, 500, "Failed to create request")
		return
	}

	// Set headers
	for k, v := range req.Headers {
		httpReq.Header.Set(k, v)
	}

	// Make the request
	client := &http.Client{}
	resp, err := client.Do(httpReq)
	if err != nil {
		sendErrorResponse(conn, req.ID, 502, "Failed to reach local service")
		return
	}
	defer resp.Body.Close()

	// Read response body
	body, err := io.ReadAll(resp.Body)
	if err != nil {
		sendErrorResponse(conn, req.ID, 500, "Failed to read response")
		return
	}

	// Convert response headers
	headers := make(map[string]string)
	for k, v := range resp.Header {
		if len(v) > 0 {
			headers[k] = v[0]
		}
	}

	// Send response back
	tunnelResp := &TunnelResponse{
		ID:         req.ID,
		StatusCode: resp.StatusCode,
		Headers:    headers,
		Body:       body,
	}

	if err := conn.WriteJSON(tunnelResp); err != nil {
		log.Printf("Error sending response: %v", err)
	}
}

func sendErrorResponse(conn *websocket.Conn, reqID string, statusCode int, message string) {
	resp := &TunnelResponse{
		ID:         reqID,
		StatusCode: statusCode,
		Headers:    map[string]string{"Content-Type": "text/plain"},
		Body:       []byte(message),
	}
	conn.WriteJSON(resp)
}