package proxy

import (
	"fmt"
	"net"

	"git.secnex.io/secnex/masterlog"
	"git.secnex.io/secnex/pgproxy/config"
)

// Proxy handles PostgreSQL connection proxying
type Proxy struct {
	listener net.Listener
	config   *config.Config
	mappings map[string]struct {
		host string
		port int
	}
}

// NewProxy creates a new proxy instance
func NewProxy(config *config.Config) (*Proxy, error) {
	addr := fmt.Sprintf("%s:%d", config.Listen.Address, config.Listen.Port)
	listener, err := net.Listen("tcp", addr)
	if err != nil {
		return nil, err
	}

	// Build mappings map for quick lookup
	mappings := make(map[string]struct {
		host string
		port int
	})
	for _, mapping := range config.Mappings {
		port := mapping.Port
		if port == 0 {
			port = 5432 // Default PostgreSQL port
		}
		mappings[mapping.External] = struct {
			host string
			port int
		}{
			host: mapping.Internal,
			port: port,
		}
	}

	return &Proxy{
		listener: listener,
		config:   config,
		mappings: mappings,
	}, nil
}

// Start starts the proxy server
func (p *Proxy) Start() error {
	masterlog.Info("PostgreSQL proxy listening", map[string]interface{}{"address": p.config.Listen.Address, "port": p.config.Listen.Port})

	for {
		conn, err := p.listener.Accept()
		if err != nil {
			masterlog.Error("Error accepting connection", map[string]interface{}{"error": err})
			continue
		}

		go p.handleConnection(conn)
	}
}