/**
 * opencoreC - Network Stack Server (Ring 3 User Space)
 * Centralized network daemon managing RTL8139 hardware NIC, ARP, DHCP, DNS, TCP/IP.
 * Listens on NET_ENDPOINT (6) and handles synchronous IPC requests from sh and gui_server.
 */

#include "stdio.h"
#include "string.h"
#include "abi/syscalls.h"
#include "abi/ipc.h"
#include "abi/net.h"

extern "C" void _start(void) {
    puts("[NET-SERVER] Initializing Hardware RTL8139 NIC & TCP/IP Stack in Ring 3...");
    net_init();

    // Acquire DHCP lease on startup
    int dhcp_res = net_dhcp_discover();
    char ip_str[32], gw_str[32];
    format_ip(g_net_cfg.ip, ip_str);
    format_ip(g_net_cfg.gateway, gw_str);
    if (dhcp_res == 0) {
        printf("[NET-SERVER] DHCP OK: IP %s, Gateway %s\n", ip_str, gw_str);
    } else {
        printf("[NET-SERVER] DHCP fallback: IP %s, Gateway %s\n", ip_str, gw_str);
    }

    uint64_t last_client = 0;
    uint64_t reply_val0 = 0;
    uint64_t reply_val1 = 0;

    while (1) {
        uint64_t sender_tid = 0;
        uint64_t opcode = 0;
        uint64_t arg0 = 0;
        uint64_t arg1 = 0;

        sysret_t ret = sys_ipc_reply_recv_raw(
            NET_ENDPOINT,
            last_client,
            reply_val0,
            reply_val1,
            &sender_tid,
            &opcode,
            &arg0,
            &arg1
        );

        if (ret == 0 && sender_tid != 0) {
            last_client = sender_tid;

            if (opcode == NET_OP_GET_CONFIG) {
                // reply_val0 = ip (low 32 bits) | (gateway << 32)
                // reply_val1 = netmask (low 32 bits) | (dns_server << 32)
                reply_val0 = ((uint64_t)g_net_cfg.gateway << 32) | (uint64_t)g_net_cfg.ip;
                reply_val1 = ((uint64_t)g_net_cfg.dns_server << 32) | (uint64_t)g_net_cfg.netmask;
            } else if (opcode == NET_OP_PING) {
                uint32_t target_ip = (uint32_t)arg0;
                uint16_t seq = (uint16_t)(arg1 ? arg1 : 1);
                int ping_res = net_send_icmp_ping(target_ip, seq);
                reply_val0 = (ping_res == 0) ? 0 : (uint64_t)-1;
                reply_val1 = 0;
            } else if (opcode == NET_OP_DNS) {
                // Domain string passed in arg0 (8 bytes) + arg1 (8 bytes)
                char domain[20] = {0};
                memcpy(domain, &arg0, 8);
                memcpy(domain + 8, &arg1, 8);
                uint32_t resolved_ip = 0;
                int res = net_dns_resolve(domain, &resolved_ip);
                reply_val0 = (res == 0) ? (uint64_t)resolved_ip : 0;
                reply_val1 = (uint64_t)res;
            } else if (opcode == NET_OP_DHCP) {
                int res = net_dhcp_discover();
                reply_val0 = (res == 0) ? (uint64_t)g_net_cfg.ip : 0;
                reply_val1 = (uint64_t)g_net_cfg.gateway;
            } else {
                reply_val0 = (uint64_t)-1;
                reply_val1 = 0;
            }
        } else {
            last_client = 0;
            sys_yield();
        }
    }
}