#include "test_handlers.h"
#include <memory>
#include <unordered_map>
#include "pico/stdlib.h"
#include "pico/time.h"
#include "net.h"
#include "icmp.h"

static ResponseTest test_discovery(const responder&) {
    ResponseTest resp;
    resp.pass = true;
    resp.messages.push_back("TODO: rewrite as deferred test");
    return resp;
}

static void test_ping(const responder& resp, ipv4::ip4_addr dst_ip) {
    auto& ns = net_get_state();
    uint16_t ping_id = 0x1234;

    uint8_t tx_buf[128];
    size_t len = icmp::build_echo_request(
        std::span{tx_buf}, ns.mac, ns.ip,
        eth::MAC_BROADCAST, dst_ip, ping_id, 1);
    if (len == 0) {
        resp.respond(ResponseTest{false, {"build_echo_request failed"}});
        return;
    }

    net_send_raw(std::span<const uint8_t>{tx_buf, len});

    ipv4::ip4_addr our_ip = ns.ip;

    auto done = std::make_shared<bool>(false);
    auto cb = std::make_shared<std::function<void(std::span<const uint8_t>)>>();
    *cb = [resp, ping_id, our_ip, done, cb](std::span<const uint8_t> frame) {
        if (*done) return;
        ipv4::ip4_addr src_ip;
        if (!icmp::parse_echo_reply(frame, src_ip, ping_id)) {
            net_add_frame_callback(*cb);
            return;
        }
        if (src_ip == our_ip) {
            net_add_frame_callback(*cb);
            return;
        }
        *done = true;
        std::string ip_str = std::to_string(src_ip[0]) + "." + std::to_string(src_ip[1]) + "." +
            std::to_string(src_ip[2]) + "." + std::to_string(src_ip[3]);
        resp.respond(ResponseTest{true, {"reply from " + ip_str}});
    };
    net_add_frame_callback(*cb);

    dispatch_schedule_ms(5000, [resp, done]() {
        if (*done) return;
        *done = true;
        resp.respond(ResponseTest{false, {"no reply from non-self host within 5s"}});
    });
}

static void test_ping_subnet(const responder& resp) {
    test_ping(resp, {169, 254, 255, 255});
}

static void test_ping_global(const responder& resp) {
    test_ping(resp, {255, 255, 255, 255});
}

using sync_test_fn = ResponseTest (*)(const responder&);
using async_test_fn = void (*)(const responder&);

struct test_entry {
    sync_test_fn sync;
    async_test_fn async;
};

static const std::unordered_map<std::string_view, test_entry> tests = {
    {"discovery", {test_discovery, nullptr}},
    {"ping_subnet", {nullptr, test_ping_subnet}},
    {"ping_global", {nullptr, test_ping_global}},
};

std::optional<ResponseListTests> handle_list_tests(const responder&, const RequestListTests&) {
    ResponseListTests resp;
    for (const auto& [name, _] : tests)
        resp.names.emplace_back(name);
    return resp;
}

std::optional<ResponseTest> handle_test(const responder& resp, const RequestTest& req) {
    auto it = tests.find(req.name);
    if (it == tests.end())
        return ResponseTest{false, {"unknown test: " + req.name}};
    if (it->second.sync)
        return it->second.sync(resp);
    it->second.async(resp);
    return std::nullopt;
}