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 */

#include <stdio.h>

#include "platform/nexus_core.hpp"
#include "platform/nexus_node.hpp"

namespace ot {
namespace Nexus {

/**
 * Time to advance for a node to form a network and become leader, in milliseconds.
 */
static constexpr uint32_t kFormNetworkTime = 13 * 1000;

/**
 * Time to advance for a node to join as a child and upgrade to a router, in milliseconds.
 */
static constexpr uint32_t kAttachToRouterTime = 30 * 1000;

void TestRouterReattach(void)
{
    Core          nexus;
    const uint8_t kNumRouters = 32;
    Node         *nodes[kNumRouters];

    Log("Creating %u nodes", kNumRouters);
    for (uint8_t i = 0; i < kNumRouters; i++)
    {
        nodes[i] = &nexus.CreateNode();
        nodes[i]->SetName("Node", i + 1);
    }

    nexus.AdvanceTime(0);

    // Step 1: Start Leader
    Log("Step 1: Starting Leader");
    nodes[0]->Get<Mle::Mle>().SetRouterUpgradeThreshold(32);
    nodes[0]->Get<Mle::Mle>().SetLeaderUpgradeThreshold(32);
    nodes[0]->Get<Mle::Mle>().SetRouterDowngradeThreshold(32);
    nodes[0]->Form();
    nexus.AdvanceTime(kFormNetworkTime);
    VerifyOrQuit(nodes[0]->Get<Mle::Mle>().IsLeader());

    // Step 2: Start other 31 routers
    Log("Step 2: Starting other 31 routers");
    for (uint8_t i = 1; i < kNumRouters; i++)
    {
        nodes[i]->Get<Mle::Mle>().SetRouterUpgradeThreshold(32);
        nodes[i]->Get<Mle::Mle>().SetRouterDowngradeThreshold(32);
        nodes[i]->Get<Mle::Mle>().SetRouterSelectionJitter(1);
        nodes[i]->Join(*nodes[0]);
        nexus.AdvanceTime(kAttachToRouterTime);
        Log("Node %u role: %s", i + 1, nodes[i]->GetExtendedRoleString());
        VerifyOrQuit(nodes[i]->Get<Mle::Mle>().IsRouter());
    }

    // Step 3: Reset Node 2 (index 1)
    Log("Step 3: Resetting Node 2");
    nodes[1]->Reset();
    nodes[1]->Get<Mle::Mle>().SetRouterUpgradeThreshold(32);
    nodes[1]->Get<Mle::Mle>().SetRouterDowngradeThreshold(32);
    nodes[1]->Get<Mle::Mle>().SetRouterSelectionJitter(3);

    // Re-enable and start
    Log("Step 4: Restarting Node 2");
    nodes[1]->Get<ThreadNetif>().Up();
    SuccessOrQuit(nodes[1]->Get<Mle::Mle>().Start());
    VerifyOrQuit(nodes[1]->Get<Mle::Mle>().GetRouterDowngradeThreshold() == 32);

    // Verify it restores as Router
    Log("Step 5: Verifying Node 2 restores as Router");
    nexus.AdvanceTime(1000);
    VerifyOrQuit(nodes[1]->Get<Mle::Mle>().IsRouter());

    // Verify it doesn't downgrade after Router Selection Jitter
    Log("Step 6: Verifying Node 2 does not downgrade");
    nexus.AdvanceTime(5000);
    VerifyOrQuit(nodes[1]->Get<Mle::Mle>().IsRouter());

    nexus.SaveTestInfo("test_router_reattach.json");
}

} // namespace Nexus
} // namespace ot

int main(void)
{
    ot::Nexus::TestRouterReattach();
    printf("All tests passed\n");
    return 0;
}