/* P1-7: HA Foundation integration tests — assembled system */
#include <stdatomic.h>
#include <stdio.h>
#include <string.h>
#include <time.h>

#include <unity/unity.h>

#include "ha.h"

/* Test 1: Single-node startup: after ha_init + ha_do_promote(priority=0),
 * role must be PRIMARY */
static void test_single_node_starts_as_primary(void)
{
    ha_state_t ha;
    ha_config_t cfg = {
        .heartbeat_interval_ms    = 3000,
        .heartbeat_timeout_ms     = 10000,
        .election_timeout_ms      = 2000,
        .probe_connect_timeout_ms = 500,
        .max_promotion_retries    = 5,
    };
    ha_init(&ha, &cfg, 0 /* priority 0 = highest */);
    /* Simulate am_i_primary() decision for priority-0 node */
    ha_do_promote(&ha);
    TEST_ASSERT_EQUAL_INT(CTRL_PRIMARY,
        (int)atomic_load_explicit(&ha.role, memory_order_acquire));
    ha_fini(&ha);
    printf("test_single_node_starts_as_primary: PASS\n");
}

/* Test 2: Term fencing — promote increments term; second promote increments again */
static void test_term_fencing_monotonic(void)
{
    ha_state_t ha;
    ha_config_t cfg = {
        .heartbeat_interval_ms    = 3000,
        .heartbeat_timeout_ms     = 10000,
        .election_timeout_ms      = 2000,
        .probe_connect_timeout_ms = 500,
        .max_promotion_retries    = 5,
    };
    ha_init(&ha, &cfg, 0);
    uint64_t t0 = atomic_load_explicit(&ha.term, memory_order_acquire);
    ha_do_promote(&ha);
    uint64_t t1 = atomic_load_explicit(&ha.term, memory_order_acquire);
    ha_do_demote(&ha);
    ha_do_promote(&ha);
    uint64_t t2 = atomic_load_explicit(&ha.term, memory_order_acquire);
    TEST_ASSERT_TRUE(t1 > t0);
    TEST_ASSERT_TRUE(t2 > t1);
    ha_fini(&ha);
    printf("test_term_fencing_monotonic: PASS\n");
}


/* Test 4: Redirect guard — primary never redirects; standby with known
 * primary redirects; standby with no known primary reports nomaster */
static void test_redirect_guard_integration(void)
{
    ha_config_t cfg = {
        .heartbeat_interval_ms    = 3000,
        .heartbeat_timeout_ms     = 10000,
        .election_timeout_ms      = 2000,
        .probe_connect_timeout_ms = 500,
        .max_promotion_retries    = 5,
    };

    /* Primary: no redirect */
    ha_state_t ha_primary;
    ha_init(&ha_primary, &cfg, 0);
    atomic_store_explicit(&ha_primary.role, (int32_t)CTRL_PRIMARY,
                          memory_order_release);
    TEST_ASSERT_EQUAL_INT(0, ha_should_redirect(&ha_primary));

    /* Standby with known primary: redirect */
    ha_state_t ha_standby;
    ha_init(&ha_standby, &cfg, 1);
    strncpy(ha_standby.primary_host, "10.0.0.1",
            sizeof(ha_standby.primary_host) - 1);
    ha_standby.primary_port = 7000;
    TEST_ASSERT_EQUAL_INT(1, ha_should_redirect(&ha_standby));
    TEST_ASSERT_EQUAL_INT(0, ha_no_primary_known(&ha_standby));

    /* Standby with no known primary: no redirect, nomaster */
    ha_state_t ha_cold;
    ha_init(&ha_cold, &cfg, 2);
    TEST_ASSERT_EQUAL_INT(0, ha_should_redirect(&ha_cold));
    TEST_ASSERT_EQUAL_INT(1, ha_no_primary_known(&ha_cold));

    ha_fini(&ha_primary);
    ha_fini(&ha_standby);
    ha_fini(&ha_cold);
    printf("test_redirect_guard_integration: PASS\n");
}

/* Test 5: Hook idempotency — double-promote does not register hooks twice
 * (full hook registration needs a cluster_t — this tests the hooks_registered
 * guard) */
static void test_hooks_registered_guard_integration(void)
{
    ha_state_t ha;
    ha_config_t cfg = {
        .heartbeat_interval_ms    = 3000,
        .heartbeat_timeout_ms     = 10000,
        .election_timeout_ms      = 2000,
        .probe_connect_timeout_ms = 500,
        .max_promotion_retries    = 5,
    };
    ha_init(&ha, &cfg, 0);
    TEST_ASSERT_EQUAL_INT(0, ha.hooks_registered);
    /* Simulate idempotency: hooks_registered = 1 after first promote */
    ha.hooks_registered = 1;
    /* Second promote should see guard and skip re-registration */
    TEST_ASSERT_TRUE(ha.hooks_registered == 1); /* guard still set */
    /* Demote resets guard */
    ha_do_demote(&ha);
    TEST_ASSERT_EQUAL_INT(0, ha.hooks_registered);
    ha_fini(&ha);
    printf("test_hooks_registered_guard_integration: PASS\n");
}

void test_p1_integration(void)
{
    RUN_TEST(test_single_node_starts_as_primary);
    RUN_TEST(test_term_fencing_monotonic);
    RUN_TEST(test_redirect_guard_integration);
    RUN_TEST(test_hooks_registered_guard_integration);
}