/*
 * 104子站示例：总召、计数量召唤、时钟同步、模拟点表、其他命令兜底及main。
 * 两种召唤共用IEC104_Interrogation.c状态机，各自有独立实例和业务事件。
 * 每轮Slave_Poll -> NextEvent逐条交付 -> Interrogation_Process；所有调用串行。
 * 总召每批4点，模块自动推进至需要等待；8个遥信和8个遥测组成6个响应ASDU。
 * QOI=21只读遥信，22只读遥测，其余分组由应用拒绝；分组点表策略不写进协议库。
 * 同一连接至多一个未终结总召，忙时不区分QOI均否定；任务满时拒绝/计数丢弃新请求，保留当前连接。
 * 总召模块处理WAIT、STOPDT及断线；应用读取业务事件，选择类型并显式交付ASDU。
 * 计数量使用8个模拟计数器；读取快照，冻结/复位由经过事件校验的同步动作入口执行。
 * 对时默认只更新模拟UTC基准；--clock system显式选择实际时钟，协议仍使用单调时钟。
 * 不支持的其他命令当场提交COT=44否定应答，复用发送层HIGH；容量不足只丢本条并计数。
 * 默认127.0.0.1:2404、CA=1；构建命令见同目录README.md。
 */
#include "IEC104_Interrogation.h"
#include "IEC104_CounterInterrogation.h"
#include "IEC104_ClockSynchronization.h"
#include "IEC60870_Clock.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define EXAMPLE_EVENT_BUDGET 32U
#define EXAMPLE_COUNTER_COUNT 8U

/* 模拟遥信点表：ioa为24位信息对象地址，value为0/1，quality为SIQ品质位（这里均为0）。
 * 表项不是线上报文，后续由SinglePointInformation_Create及ASDU容器编码成Type=1。
 * 示例点表只读；接真实数据源时，在每次NEED_DATA组包处读取所选点的当前值和品质。 */
static const struct { uint32_t ioa; uint8_t value, quality; } example_signals[] = {
    {1001, 0, 0}, {1002, 1, 0}, {1003, 0, 0}, {1004, 1, 0},
    {1005, 1, 0}, {1006, 0, 0}, {1007, 1, 0}, {1008, 0, 0}
};
/* 模拟遥测点表：ioa为信息对象地址，value为原始有符号16位标度值，quality为QDS品质位。
 * 编码为不带时标的Type=11；本示例不定义物理单位和倍率，负数也按有符号值传输。 */
static const struct { uint32_t ioa; int16_t value; uint8_t quality; } example_measurements[] = {
    {2001, 2300, 0}, {2002, 2310, 0}, {2003, 2290, 0}, {2004, 5000, 0},
    {2005, -125, 0}, {2006, 0, 0}, {2007, 1234, 0}, {2008, 42, 0}
};
/* 点数直接取数组长度；分批游标使用size_t，不另维护可能与点表不一致的手写数量。 */
#define EXAMPLE_SIGNAL_COUNT (sizeof(example_signals) / sizeof(example_signals[0]))
#define EXAMPLE_MEASUREMENT_COUNT (sizeof(example_measurements) / sizeof(example_measurements[0]))


/* 当前取数站的应用游标；首个NEED_DATA才初始化，协议库不登记或冻结业务IOA列表。 */
typedef struct { size_t single_index, scaled_index; } ExampleGiData;

typedef struct {
    IEC104_Slave_t *slave; /* main拥有；本上下文仅借用。 */
    IEC104_Station_t station; /* 应用拥有的固定地址站点节点，供各业务共用CA和context。 */
    IEC104_Interrogation_t *interrogation; /* 库内不透明总召任务对象。 */
    IEC104_InterrogationStatus_t gi; /* 只读快照，用于调度等待及统计。 */
    IEC104_Interrogation_t *counter; /* 独立计数量实例，与总召共用Slave，不共用任务和广播状态区。 */
    IEC104_InterrogationStatus_t ci; /* 计数量调度及统计快照，每次推进后重新查询。 */
    IEC104_ClockSynchronization_t *clock; /* 独立时钟同步模块，共用Slave及站点表。 */
    IEC104_ClockSynchronizationStatus_t cs; /* 对时执行、确认及期限的只读快照。 */
    bool clock_system, clock_valid; /* 实际设时为显式选项；clock_valid只描述模拟基准。 */
    uint64_t clock_utc_ms, clock_base_ms; /* 模拟UTC毫秒及其单调基准，不影响协议计时。 */
    IEC104_InterrogationEvent_t counter_event; /* WAIT时保留的原业务事件，重试不能换成新身份。 */
    bool counter_pending, counter_first; /* 是否持有待应答事件、本轮是否先推进计数量。 */
    int32_t counter_current[EXAMPLE_COUNTER_COUNT]; /* 模拟当前累计值，冻结及复位动作的数据源。 */
    IEC60870_BinaryCounterReading_t counter_frozen[EXAMPLE_COUNTER_COUNT]; /* 最近冻结值及BCR序号、品质。 */
    IEC60870_BinaryCounterReading_t counter_snapshot[EXAMPLE_COUNTER_COUNT]; /* 本轮读取固定的冻结副本。 */
    size_t counter_cursor, counter_end; /* 当前读取区间，只有Submit_Batch成功才推进游标。 */
    uint64_t counter_instance, counter_request; /* 快照归属；旧FINISHED不得清理新请求。 */
    IEC104_Station_t *counter_station; /* 读取期间额外持有的原站节点，结束后归还引用。 */
    unsigned long counter_completed; /* 已消费的COMPLETED通知数，包含读取及冻结/复位。 */
    ExampleGiData gi_data; /* 应用拥有的游标，库内没有session或回调参数。 */
    IEC104_Station_t *gi_station; /* 取数期间持有原站，Complete_Data或FINISHED时释放。 */
    uint64_t session_instance, session_request; /* 只清理对应请求的遍历状态及业务资源。 */
    IEC104_InterrogationEvent_t business_event; /* 纯值，可保存到后续循环应答。 */
    bool business_pending;
    int batch_result; /* 本例构造结果：-1失败、0数据结束、1有数据。 */
    IEC60870_Asdu_t batch; /* 借用本应用bytes；Submit_Batch(OK)后可复用。 */
    uint8_t batch_bytes[IEC104_MAX_ASDU_LEN];
    bool events_pending;
    unsigned long other_submitted, other_rejected, other_cancelled, other_overloads;
} ExampleApp;

/* 普通应用函数，只由下面的事件分支直接调用，不注册到库中。
 * 应用自行选择本批IOA、类型及分组成员；为NEED_DATA构造一种类型的一批。
 * 真实取值应放在下列逐点组包处，值与品质的读取一致性由数据源保证；不预读整轮数据。
 * FULL不跳过当前点；本函数不推进持久游标，Submit_Batch(OK)后才推进。
 * WAIT仅保留事件，每次重试重读当前值。点值更新/突发发布与本次组包/提交须串行协调。
 * 逐批取值不保证整轮同一采样时刻。 */
static int Example_Build_Batch(ExampleApp *app, const IEC104_InterrogationRequest_t *request)
{
    ExampleGiData *data = &app->gi_data;
    IEC60870_Asdu_t *asdu = &app->batch;
    IEC60870_AsduHeader_t header;
    IEC104_Station_t *station = request->station_id != 0U ?
        IEC104_Slave_Get_Station_By_Id(app->slave, request->station_id) :
        IEC104_Slave_Get_Station(app->slave, request->common_address);
    if (IEC104_Station_Get_Context(station) != app) {
        return -1;
    }
    memset(&header, 0, sizeof(header));
    header.cause_of_transmission = request->qualifier; /* 站总召20，分组总召21..36。 */
    header.common_address = request->common_address;
    header.originator_address = request->originator_address;
    header.is_test = request->is_test;
    if (IEC60870_Asdu_Create(asdu, IEC104_Slave_Get_Application_Layer_Parameters(app->slave),
        app->batch_bytes, sizeof(app->batch_bytes), &header, 0) != IEC60870_ASDU_OK) { return -1; }
    if (data->single_index < EXAMPLE_SIGNAL_COUNT) {
        size_t index = data->single_index;
        while (index < EXAMPLE_SIGNAL_COUNT && asdu->object_count < request->max_objects_per_asdu) {
            IEC60870_SinglePointInformation_t point;
            IEC60870_AsduResult_t added;
            if (IEC60870_SinglePointInformation_Create(&point, example_signals[index].ioa,
                example_signals[index].value, example_signals[index].quality) != IEC60870_ASDU_OK) {
                return -1;
            }
            added = IEC60870_Asdu_Add_InformationObject(asdu, &point.object);
            if (added == IEC60870_ASDU_FULL) { break; }
            if (added != IEC60870_ASDU_OK) { return -1; }
            ++index;
        }
    } else if (data->scaled_index < EXAMPLE_MEASUREMENT_COUNT) {
        size_t index = data->scaled_index;
        while (index < EXAMPLE_MEASUREMENT_COUNT && asdu->object_count < request->max_objects_per_asdu) {
            IEC60870_MeasuredValueScaled_t point;
            IEC60870_AsduResult_t added;
            if (IEC60870_MeasuredValueScaled_Create(&point, example_measurements[index].ioa,
                example_measurements[index].value, example_measurements[index].quality) != IEC60870_ASDU_OK) {
                return -1;
            }
            added = IEC60870_Asdu_Add_InformationObject(asdu, &point.object);
            if (added == IEC60870_ASDU_FULL) { break; }
            if (added != IEC60870_ASDU_OK) { return -1; }
            ++index;
        }
    } else { return 0; }
    return asdu->object_count != 0U ? 1 : -1;
}

/* 释放应用为当前取数持有的节点引用并清空游标，库的广播状态区仍独立保存协议进度。
 * Complete_Data成功即可调用，让下一站复用游标；不需要等本轮所有站的FINISHED。 */
static bool Example_End_Data(ExampleApp *app)
{
    if (app->gi_station != NULL &&
        IEC104_Slave_Release_Station(app->slave, app->gi_station) != IEC104_STATION_OK) { return false; }
    app->gi_station = NULL;
    memset(&app->gi_data, 0, sizeof(app->gi_data));
    app->session_instance = app->session_request = 0U;
    return true;
}

/* 第二条事件流：应用主动取业务事件，再显式应答；没有库调用应用函数的路径。
 * 常量点表立即就绪；异步数据源可在NEED_DATA保留business_event，完成采样后再Submit。
 * WAIT先处理Slave通知并推进网络，下次重取数据；STALE表示交互已失效，不重试过期事件。 */
static bool Example_Drain_Business(ExampleApp *app)
{
    unsigned count;
    for (count = 0U; count < EXAMPLE_EVENT_BUDGET; ++count) {
        IEC104_InterrogationEvent_t *event = &app->business_event;
        IEC104_InterrogationReplyResult_t reply;
        if (!app->business_pending) {
            IEC104_InterrogationNextResult_t next = IEC104_Interrogation_NextEvent(app->interrogation, event);
            if (next == IEC104_INTERROGATION_NEXT_EMPTY) { return true; }
            if (next != IEC104_INTERROGATION_NEXT_READY) { return false; }
            app->business_pending = true;
        }
        switch (event->type) {
        case IEC104_INTERROGATION_BEGIN: {
            bool accept = event->request.qualifier <= 22U;
            /* 示例仅定义组1=遥信、组2=遥测；拒绝未配置的组。协议库支持全部16组。
             * 广播会先交付所有站的BEGIN；这里只作准入判断，不占用唯一取数游标。 */
            reply = IEC104_Interrogation_Reply_Begin(app->interrogation, event, accept);
            break;
        }
        case IEC104_INTERROGATION_NEED_DATA:
            /* 广播逐站取数，因此首个NEED_DATA才建立游标；用注册编号取得原站，避免同CA替换串站。
             * 应用单独Acquire，确保库交付FINISHED并归还自己的引用时，应用清理仍有有效节点。 */
            if (event->request_id != app->session_request || event->instance_id != app->session_instance) {
                if (app->session_request != 0U) { return false; }
                if (event->request.station_id != 0U) {
                    app->gi_station = IEC104_Slave_Get_Station_By_Id(app->slave, event->request.station_id);
                    if (app->gi_station == NULL ||
                        IEC104_Slave_Acquire_Station(app->slave, app->gi_station) != IEC104_STATION_OK) { return false; }
                }
                memset(&app->gi_data, 0, sizeof(app->gi_data));
                if (event->request.qualifier == 21U) { app->gi_data.scaled_index = EXAMPLE_MEASUREMENT_COUNT; }
                if (event->request.qualifier == 22U) { app->gi_data.single_index = EXAMPLE_SIGNAL_COUNT; }
                app->session_instance = event->instance_id;
                app->session_request = event->request_id;
            }
            app->batch_result = Example_Build_Batch(app, &event->request);
            if (app->batch_result < 0) { reply = IEC104_Interrogation_Fail_Request(app->interrogation, event); }
            else if (app->batch_result == 0) { reply = IEC104_Interrogation_Complete_Data(app->interrogation, event); }
            else { reply = IEC104_Interrogation_Submit_Batch(app->interrogation, event, &app->batch); }
            if (reply == IEC104_INTERROGATION_REPLY_OK && app->batch_result > 0) {
                if (app->gi_data.single_index < EXAMPLE_SIGNAL_COUNT) {
                    app->gi_data.single_index += app->batch.object_count;
                } else { app->gi_data.scaled_index += app->batch.object_count; }
            } else if (reply == IEC104_INTERROGATION_REPLY_OK && app->batch_result == 0) {
                /* 其他站的数据随后才开始；无需等到所有站的ACT_TERM才复用游标。 */
                if (!Example_End_Data(app)) { return false; }
            }
            break;
        case IEC104_INTERROGATION_FINISHED:
            /* 完成、本地取消、主站撤销、超时、断线和失败统一清理。
             * 真实异步采样还需在这里停止对应任务；迟到的旧FINISHED不清理新请求资源。 */
            if (event->instance_id == app->session_instance && event->request_id == app->session_request) {
                if (!Example_End_Data(app)) { return false; }
            }
            reply = IEC104_INTERROGATION_REPLY_OK; /* 终结通知无需调用任何应答接口。 */
            break;
        default: return false;
        }
        /* WAIT保留business_event且游标不动；下轮重新Build_Batch，不重发缓存的旧点值。 */
        if (reply == IEC104_INTERROGATION_REPLY_WAIT) { return true; }
        if (reply != IEC104_INTERROGATION_REPLY_OK && reply != IEC104_INTERROGATION_REPLY_STALE) { return false; }
        app->business_pending = false;
    }
    return true;
}

/* 同步模拟计数器动作：执行入口先验证事件，WAIT/STALE不调用本函数。
 * 只在内存中一次完成选中组的操作；不调用网络，不再次进入召唤模块。
 * 实际外部电表命令需要独立的执行结果和重复请求策略，不能套用此同步函数。 */
static bool Example_Counter_Action(void *context, const IEC104_InterrogationRequest_t *request)
{
    ExampleApp *app = (ExampleApp *)context;
    size_t first, end, index;
    if (request->is_test || (request->qualifier != 1U && request->qualifier != 2U &&
        request->qualifier != 5U) || request->freeze == 0U || request->freeze > 3U) { return false; }
    first = request->qualifier == 2U ? 4U : 0U;
    end = request->qualifier == 1U ? 4U : EXAMPLE_COUNTER_COUNT;
    for (index = first; index < end; ++index) {
        if (request->freeze != 3U) {
            app->counter_frozen[index].value = app->counter_current[index];
            app->counter_frozen[index].sequence_number =
                (uint8_t)((app->counter_frozen[index].sequence_number + 1U) & 31U);
        }
        if (request->freeze >= 2U) { app->counter_current[index] = 0; }
    }
    return true;
}

/* 释放当前读取的节点引用和快照归属；快照字节无需清零，下次读取会整体覆盖。
 * Complete_Data成功或匹配的FINISHED都可收尾，冻结动作本身不占用读取游标。 */
static bool Example_End_Counter(ExampleApp *app)
{
    if (app->counter_station != NULL &&
        IEC104_Slave_Release_Station(app->slave, app->counter_station) != IEC104_STATION_OK) { return false; }
    app->counter_station = NULL;
    app->counter_instance = app->counter_request = 0U;
    app->counter_cursor = app->counter_end = 0U;
    return true;
}

/* 从本轮固定快照构造一个Type15、SQ=0批次，共用ASDU缓冲但不推进游标。
 * 返回1表示非空批次，0表示所选组已读完，-1表示构造失败；WAIT后仍取同一快照重组。 */
static int Example_Build_Counter_Batch(ExampleApp *app, const IEC104_InterrogationRequest_t *request)
{
    IEC60870_AsduHeader_t header;
    size_t index;
    if (app->counter_cursor == app->counter_end) { return 0; }
    memset(&header, 0, sizeof(header));
    header.cause_of_transmission = request->data_cause;
    header.common_address = request->common_address;
    header.originator_address = request->originator_address;
    header.is_test = request->is_test;
    if (IEC60870_Asdu_Create(&app->batch, IEC104_Slave_Get_Application_Layer_Parameters(app->slave),
        app->batch_bytes, sizeof(app->batch_bytes), &header, 0) != IEC60870_ASDU_OK) { return -1; }
    for (index = app->counter_cursor; index < app->counter_end &&
        app->batch.object_count < request->max_objects_per_asdu; ++index) {
        IEC60870_IntegratedTotals_t point;
        IEC60870_AsduResult_t result;
        if (IEC60870_IntegratedTotals_Create(&point, (uint32_t)(3001U + index),
            &app->counter_snapshot[index]) != IEC60870_ASDU_OK) { return -1; }
        result = IEC60870_Asdu_Add_InformationObject(&app->batch, &point.object);
        if (result == IEC60870_ASDU_FULL) { break; }
        if (result != IEC60870_ASDU_OK) { return -1; }
    }
    return app->batch.object_count != 0U ? 1 : -1;
}

/* 冻结值在首个NEED_DATA固定为本轮快照；WAIT重建报文也使用同一份值、序号和品质。
 * 模拟点值属于本应用；真实共享数据源应在其锁内取得快照后再进行网络提交。 */
static bool Example_Drain_Counter(ExampleApp *app)
{
    unsigned count;
    if (app->counter == NULL) { return true; }
    for (count = 0U; count < EXAMPLE_EVENT_BUDGET; ++count) {
        IEC104_InterrogationEvent_t *event = &app->counter_event;
        IEC104_InterrogationReplyResult_t reply;
        if (!app->counter_pending) {
            IEC104_InterrogationNextResult_t next = IEC104_Interrogation_NextEvent(app->counter, event);
            if (next == IEC104_INTERROGATION_NEXT_EMPTY) { return true; }
            if (next != IEC104_INTERROGATION_NEXT_READY) { return false; }
            app->counter_pending = true;
        }
        switch (event->type) {
        case IEC104_INTERROGATION_BEGIN: {
            IEC104_Station_t *station = IEC104_Slave_Get_Station_By_Id(app->slave, event->request.station_id);
            bool accept = IEC104_Station_Get_Context(station) == app &&
                (event->request.qualifier == 1U || event->request.qualifier == 2U || event->request.qualifier == 5U);
            if (accept && event->request.freeze != 0U && !event->request.is_test) {
                reply = IEC104_CounterInterrogation_Execute_Begin(app->counter, event, Example_Counter_Action, app);
            } else {
                reply = IEC104_Interrogation_Reply_Begin(app->counter, event,
                    accept && event->request.freeze == 0U);
            }
            break;
        }
        case IEC104_INTERROGATION_NEED_DATA: {
            int built;
            if (event->instance_id != app->counter_instance || event->request_id != app->counter_request) {
                IEC104_Station_t *station;
                if (app->counter_request != 0U) { return false; }
                station = IEC104_Slave_Get_Station_By_Id(app->slave, event->request.station_id);
                if (station == NULL || IEC104_Station_Get_Context(station) != app ||
                    IEC104_Slave_Acquire_Station(app->slave, station) != IEC104_STATION_OK) { return false; }
                app->counter_station = station;
                memcpy(app->counter_snapshot, app->counter_frozen, sizeof(app->counter_snapshot));
                app->counter_cursor = event->request.qualifier == 2U ? 4U : 0U;
                app->counter_end = event->request.qualifier == 1U ? 4U : EXAMPLE_COUNTER_COUNT;
                app->counter_instance = event->instance_id;
                app->counter_request = event->request_id;
            }
            built = Example_Build_Counter_Batch(app, &event->request);
            if (built < 0) { reply = IEC104_Interrogation_Fail_Request(app->counter, event); }
            else if (built == 0) { reply = IEC104_Interrogation_Complete_Data(app->counter, event); }
            else { reply = IEC104_Interrogation_Submit_Batch(app->counter, event, &app->batch); }
            if (reply == IEC104_INTERROGATION_REPLY_OK) {
                if (built > 0) { app->counter_cursor += app->batch.object_count; }
                else if (built == 0 && !Example_End_Counter(app)) { return false; }
            }
            break;
        }
        case IEC104_INTERROGATION_FINISHED:
            if (event->reason == IEC104_INTERROGATION_FINISH_COMPLETED) { ++app->counter_completed; }
            if (event->instance_id == app->counter_instance && event->request_id == app->counter_request &&
                !Example_End_Counter(app)) { return false; }
            reply = IEC104_INTERROGATION_REPLY_OK;
            break;
        default: return false;
        }
        if (reply == IEC104_INTERROGATION_REPLY_WAIT) { return true; }
        if (reply != IEC104_INTERROGATION_REPLY_OK && reply != IEC104_INTERROGATION_REPLY_STALE) { return false; }
        app->counter_pending = false;
    }
    return true;
}

/* 必须在开始消费Slave事件之前创建业务模块；config本地对象按值复制，广播数组仍为借用。
 * 单站可传NULL/0；多站广播须提供覆盖全部目标的数组，保持独占和地址稳定直到模块Destroy。 */
static bool Example_Init(ExampleApp *app, IEC104_Slave_t *slave, uint16_t common_address,
    IEC104_InterrogationStationState_t *broadcast_states, size_t broadcast_capacity)
{
    IEC104_InterrogationConfig_t config;
    memset(app, 0, sizeof(*app));
    app->slave = slave;
    if (IEC104_Slave_Add_Station(slave, &app->station, common_address, app) != IEC104_STATION_OK) { return false; }
    IEC104_Interrogation_Config_Default(&config);
    config.use_station_registry = true; /* CA只在注册时指定；多站广播需提供每站状态区。 */
    config.broadcast_states = broadcast_states;
    config.broadcast_capacity = broadcast_capacity;
    config.max_objects_per_asdu = 4U;
    app->interrogation = IEC104_Interrogation_Create(slave, &config);
    if (app->interrogation == NULL) { (void)IEC104_Slave_Remove_Station(slave, &app->station); }
    return app->interrogation != NULL;
}

/* 计数量实例可选，独立提供广播状态区；不共享总召的数组或取数游标。
 * CLI仅注册一站。测试可给多个CA注册同一app，它们会指向同一组模拟计数器；
 * 真实多站应用应让各站context分别拥有计数器数据，尤其不要逐站复位同一物理源。 */
static bool Example_Init_Counters(ExampleApp *app,
    IEC104_InterrogationStationState_t *broadcast_states, size_t broadcast_capacity)
{
    static const int32_t initial[EXAMPLE_COUNTER_COUNT] = {120000, 345600, 7890, 0, 1, 65535, INT32_MAX, 42};
    IEC104_InterrogationConfig_t config;
    size_t index;
    if (app->counter != NULL) { return false; }
    IEC104_Interrogation_Config_Default(&config);
    config.use_station_registry = true;
    config.broadcast_states = broadcast_states;
    config.broadcast_capacity = broadcast_capacity;
    config.max_objects_per_asdu = 4U;
    app->counter = IEC104_CounterInterrogation_Create(app->slave, &config);
    if (app->counter == NULL) { return false; }
    for (index = 0U; index < EXAMPLE_COUNTER_COUNT; ++index) {
        app->counter_current[index] = initial[index];
        app->counter_frozen[index].value = initial[index];
    }
    return true;
}

/* 执行检查已完成时区换算和滞留补偿；动作不重复补偿，也不推进网络事件循环。 */
static bool Example_Clock_Action(void *context, const IEC104_ClockSynchronizationRequest_t *request)
{
    ExampleApp *app = (ExampleApp *)context;
    if (app->clock_system) { return IEC60870_Clock_Set(&request->local_time) != 0; }
    app->clock_utc_ms = request->utc_ms;
    app->clock_base_ms = request->base_ms;
    app->clock_valid = true;
    return true;
}

/* config可为NULL采用默认值；创建须早于消费Slave通知，实例独占自身请求和确认状态。 */
static bool Example_Init_Clock(ExampleApp *app, const IEC104_ClockSynchronizationConfig_t *config)
{
    IEC104_ClockSynchronizationConfig_t defaults;
    if (app->clock != NULL) { return false; }
    if (config == NULL) {
        IEC104_ClockSynchronization_Config_Default(&defaults);
        config = &defaults;
    }
    app->clock = IEC104_ClockSynchronization_Create(app->slave, config);
    return app->clock != NULL;
}

/* 每轮最多执行事件预算条请求；WAIT先交回Slave消费通知，不重放已经执行的动作。 */
static bool Example_Drain_Clock(ExampleApp *app)
{
    unsigned count;
    if (app->clock == NULL) { return true; }
    for (count = 0U; count < EXAMPLE_EVENT_BUDGET; ++count) {
        IEC104_ClockSynchronizationExecuteResult_t result =
            IEC104_ClockSynchronization_Execute_Next(app->clock, Example_Clock_Action, app);
        if (result == IEC104_CLOCK_SYNCHRONIZATION_EXECUTE_EMPTY ||
            result == IEC104_CLOCK_SYNCHRONIZATION_EXECUTE_WAIT) { return true; }
        if (result != IEC104_CLOCK_SYNCHRONIZATION_EXECUTE_OK) { return false; }
    }
    return true;
}

static void Example_Cancel(ExampleApp *app)
{
    IEC104_Interrogation_Cancel(app->interrogation);
    if (app->counter != NULL) {
        IEC104_Interrogation_Cancel(app->counter);
        (void)IEC104_Interrogation_Get_Status(app->counter, &app->ci);
    }
    if (app->clock != NULL) {
        IEC104_ClockSynchronization_Cancel(app->clock);
        (void)IEC104_ClockSynchronization_Get_Status(app->clock, &app->cs);
    }
    (void)IEC104_Interrogation_Get_Status(app->interrogation, &app->gi);
}

/* 每次等待前重新查询剩余期限，避免采样/业务处理耗时后继续使用旧的毫秒数。
 * 本地可推进时不休眠；否则本例网络等待最多50ms，并受最近业务期限限制。 */
static uint32_t Example_Wait_Time(ExampleApp *app, uint32_t maximum_ms)
{
    if (!IEC104_Interrogation_Get_Status(app->interrogation, &app->gi)) { return 0U; }
    if (app->counter != NULL) {
        if (!IEC104_Interrogation_Get_Status(app->counter, &app->ci)) { return 0U; }
        if (app->ci.events_pending || app->ci.pending_events != 0U || app->ci.need_process) { return 0U; }
        if (app->ci.timer_active && app->ci.timeout_remaining_ms < maximum_ms) {
            maximum_ms = app->ci.timeout_remaining_ms;
        }
    }
    if (app->clock != NULL) {
        if (!IEC104_ClockSynchronization_Get_Status(app->clock, &app->cs)) { return 0U; }
        if (app->cs.events_pending || app->cs.execute_pending || app->cs.need_process) { return 0U; }
        if (app->cs.timer_active && app->cs.timeout_remaining_ms < maximum_ms) {
            maximum_ms = app->cs.timeout_remaining_ms;
        }
    }
    if (app->events_pending || app->gi.events_pending || app->gi.pending_events != 0U ||
        app->gi.need_process) { return 0U; }
    if (app->gi.timer_active && app->gi.timeout_remaining_ms < maximum_ms) { return app->gi.timeout_remaining_ms; }
    return maximum_ms;
}

/* 状态事件交给所有实例；I帧依次由总召、计数量、时钟同步及未知类型兜底接手。 */
static bool Example_Handle_Event(ExampleApp *app, const IEC104_SlaveEvent_t *event)
{
    IEC104_InterrogationEventResult_t result;
    /* Receiver已过滤线上基础格式错误；仍防御性过滤不可用视图，避免误交给业务分派或未知类型兜底。 */
    if (event->transport.type == IEC104_TCP_EVENT_I_FRAME && event->asdu_result != IEC60870_ASDU_OK) { return true; }
    result = IEC104_Interrogation_Handle_Event(app->interrogation, event);
    if (app->counter != NULL && (event->transport.type != IEC104_TCP_EVENT_I_FRAME ||
        result == IEC104_INTERROGATION_EVENT_IGNORED)) {
        IEC104_InterrogationEventResult_t counter_result = IEC104_Interrogation_Handle_Event(app->counter, event);
        if (counter_result == IEC104_INTERROGATION_EVENT_ERROR ||
            !IEC104_Interrogation_Get_Status(app->counter, &app->ci)) { return false; }
        if (result == IEC104_INTERROGATION_EVENT_IGNORED) { result = counter_result; }
    }
    if (result == IEC104_INTERROGATION_EVENT_ERROR ||
        !IEC104_Interrogation_Get_Status(app->interrogation, &app->gi)) { return false; }
    if (app->clock != NULL && (event->transport.type != IEC104_TCP_EVENT_I_FRAME ||
        result == IEC104_INTERROGATION_EVENT_IGNORED)) {
        IEC104_ClockSynchronizationEventResult_t clock_result =
            IEC104_ClockSynchronization_Handle_Event(app->clock, event);
        if (clock_result == IEC104_CLOCK_SYNCHRONIZATION_EVENT_ERROR ||
            !IEC104_ClockSynchronization_Get_Status(app->clock, &app->cs)) { return false; }
        if (clock_result != IEC104_CLOCK_SYNCHRONIZATION_EVENT_IGNORED) { return true; }
    }
    if (result != IEC104_INTERROGATION_EVENT_IGNORED ||
        event->transport.type != IEC104_TCP_EVENT_I_FRAME || !app->gi.active ||
        event->transport.generation != app->gi.generation) { return true; }
    /* 当前事件当场提交，必须在NextEvent读取后续通知之前调用；应用不保存兜底请求。
     * HIGH满只丢本条并计数；原连接停用/断开则取消，不跨启停续发。 */
    ++app->other_rejected;
    switch (IEC104_Slave_Reject_Request(app->slave, event, IEC60870_ASDU_COT_UNKNOWN_TYPE)) {
    case IEC104_TCP_SUBMIT_OK: ++app->other_submitted; break;
    case IEC104_TCP_SUBMIT_WAIT: ++app->other_overloads; break;
    case IEC104_TCP_SUBMIT_FATAL:
        /* 可能已写出字节；cancelled仅表示不再重试，继续读取断线通知。 */
        ++app->other_cancelled;
        break;
    default: ++app->other_cancelled; break;
    }
    return true;
}

/* 两种业务各自推进协议、消费业务事件并刷新状态，供外层轮换调用次序。 */
static bool Example_Step_General(ExampleApp *app)
{
    return IEC104_Interrogation_Process(app->interrogation) && Example_Drain_Business(app) &&
        IEC104_Interrogation_Get_Status(app->interrogation, &app->gi);
}

/* 仅总召测试不创建计数量实例，此时直接完成本轮；已创建时采用相同推进顺序。 */
static bool Example_Step_Counter(ExampleApp *app)
{
    return app->counter == NULL || (IEC104_Interrogation_Process(app->counter) && Example_Drain_Counter(app) &&
        IEC104_Interrogation_Get_Status(app->counter, &app->ci));
}

static bool Example_Step_Clock(ExampleApp *app)
{
    return app->clock == NULL || (IEC104_ClockSynchronization_Process(app->clock) &&
        Example_Drain_Clock(app) && IEC104_ClockSynchronization_Get_Status(app->clock, &app->cs));
}

/* 两类召唤轮流先执行，再推进对时；发送WAIT后下一轮继续，不只靠need_process重试。 */
static bool Example_Step(ExampleApp *app)
{
    if (app->events_pending) { return true; }
    app->counter_first = !app->counter_first;
    if (app->counter_first) {
        if (!Example_Step_Counter(app) || !Example_Step_General(app)) { return false; }
    } else {
        if (!Example_Step_General(app) || !Example_Step_Counter(app)) { return false; }
    }
    return Example_Step_Clock(app);
}

/* 有界消费通知。预算用完先续读，不能跨过排在后面的STOP/START直接续发旧总召。 */
static bool Example_Drain(ExampleApp *app)
{
    unsigned count;
    IEC104_SlaveEvent_t event;
    for (count = 0U; count < EXAMPLE_EVENT_BUDGET; ++count) {
        IEC104_TcpEventResult_t result = IEC104_Slave_NextEvent(app->slave, &event);
        if (result == IEC104_TCP_EVENT_EMPTY) { app->events_pending = false; return true; }
        if (result != IEC104_TCP_EVENT_READY || !Example_Handle_Event(app, &event)) { return false; }
    }
    app->events_pending = true;
    return true;
}

#ifndef IEC104_SLAVE_EXAMPLE_NO_MAIN
#ifndef _WIN32
#error "This executable uses the Windows network backend"
#endif
#ifndef _WIN32_WINNT
/* GetTickCount64所需的最低Windows API声明；这里只用于示例运行时长，不处理业务时标。 */
#define _WIN32_WINNT 0x0600
#endif
#ifndef WIN32_LEAN_AND_MEAN
/* 只引入本入口需要的Windows基础声明，socket操作仍全部留在协议库的Net后端。 */
#define WIN32_LEAN_AND_MEAN
#endif
#include <windows.h>
#include <errno.h>
#include <signal.h>

/* 信号处理器和主循环之间只交换停止标志；静态初始化为0，不在信号处理器中访问任务或网络。 */
static volatile sig_atomic_t example_stop;

/**
 * 功能：在已注册的停止信号到来时请求主循环退出。
 * 输入参数：signal_number——运行库传入的信号编号，这里不区分SIGINT与SIGTERM。
 * 输出参数：example_stop置1。
 * 返回值：无。
 * 说明：信号上下文只写sig_atomic_t，不打印、不分配、不调用Slave；资源由main正常收尾。
 */
static void Example_Stop(int signal_number) { (void)signal_number; example_stop = 1; }

/**
 * 功能：把纯十进制命令行文本解析为不超过max的unsigned long。
 * 输入参数：text——非NULL且以NUL结束的字符串；max——此选项允许的最大值。
 * 输出参数：value——非NULL输出存储，仅成功时写入；失败保持原值。
 * 返回值：true为整个字符串解析成功且未越界；false为空串、符号/空白前缀、尾部字符或溢出。
 * 说明：先检查再截窄为端口、CA或窗口类型，避免越界数值被静默截断；允许前导零及数值0。
 *       某些选项禁止0，由main另查；端口0表示自动分配，run-ms=0表示持续运行。
 */
static bool Example_Number(const char *text, unsigned long max, unsigned long *value)
{
    char *end;
    unsigned long parsed;
    if (text[0] < '0' || text[0] > '9') { return false; }
    /* strtoul通过errno报告数值溢出；先清零，避免沿用上一次库调用的错误。 */
    errno = 0;
    parsed = strtoul(text, &end, 10);
    if (errno != 0 || *end != '\0' || parsed > max) { return false; }
    *value = parsed;
    return true;
}

/**
 * 功能：向标准输出打印本示例支持的选项、默认监听配置及模拟点地址范围。
 * 输入参数：program——非NULL程序名称，main传入argv[0]。
 * 输出参数：无，文本写入stdout。
 * 返回值：无。
 * 说明：本函数不创建服务或退出进程；main根据--help或缺少参数分别选择成功/失败退出。
 */
static void Example_Usage(const char *program)
{
    printf("Usage: %s [--bind IPv4] [--port 0..65535] [--ca 1..65534]\n"
           "       [--window 1..32767] [--run-ms milliseconds] [--clock simulated|system]\n"
           "Defaults: 127.0.0.1:2404, CA=1, k=12, run until Ctrl+C.\n"
           "GI: QOI=20 (all), 21 (signals), 22 (scaled); IOA=0.\n"
           "Signals 1001..1008, scaled values 2001..2008; COT=8 cancels matching GI.\n"
           "Counters 3001..3008: RQT=5 (all), 1/2 (groups); Type 15, four per batch.\n"
           "FRZ=0 reads frozen values; 1 freezes; 2 freezes/resets; 3 resets.\n"
           "Freeze/reset completes with ACT_CON only; TEST actions and COT=8 are rejected.\n"
           "Clock: simulated by default; system sets the actual clock and requires permission.\n"
           "Clock requests use UTC+8 standard time; TEST is rejected without setting time.\n", program);
}

/**
 * 功能：配置并运行子站示例，退出时关闭服务、读空通知并归还静态槽。
 * 输入参数：argc/argv——命令行；除--help外，每个选项后都须有一个值。
 * 输出参数：stdout输出帮助、监听端点和累计统计；stderr输出参数或运行失败信息。
 * 返回值：EXIT_SUCCESS为帮助输出或正常停止；参数、初始化、运行或清理失败为EXIT_FAILURE。
 * 说明：服务生命周期为Create -> Init -> 循环Poll/Drain/Step -> Close -> 读空事件 -> Destroy。
 *       main拥有Slave句柄，app只借用；静态app和库内任务在整个运行期间保持地址不变。
 *       run-ms使用单调毫秒时钟，在循环边界检查，表示约定运行时长而非精确的退出截止时刻。
 */
int main(int argc, char **argv)
{
    static ExampleApp app; /* 注册站点及业务借用的存储在退出前保持地址不变。 */
    IEC104_SlaveConfig_t config;       /* 本地配置，Slave_Init会复制，不在运行中借用它。 */
    IEC104_TcpError_t error;           /* 最近一次服务接口调用的诊断，与历史网络错误分开。 */
    IEC104_TcpServerStatus_t status;   /* 启动后查询实际端口，尤其用于--port=0。 */
    IEC104_Slave_t *slave;             /* main持有的唯一服务句柄，清理结束后不再使用。 */
    IEC104_TcpResult_t result;         /* 服务结果须显式比较IEC104_TCP_OK，不能作布尔判断。 */
    uint16_t common_address = 1U;      /* 应用地址校验条件，不是TCP端口或单点IOA。 */
    unsigned long run_ms = 0U;        /* 0为持续运行，非零为命令行指定的运行毫秒数。 */
    bool clock_system = false;       /* 默认模拟；解析后再写入Example_Init清零后的app。 */
    uint64_t started;                 /* 开始主循环前的单调时刻，与CP56日历时间无关。 */
    int arg, exit_code = EXIT_SUCCESS; /* arg遍历选项和值；任一阶段失败后保留失败退出码。 */
    /* 第1步：采用库的协议默认值，只把示例默认监听地址收窄到本机回环地址。 */
    IEC104_Slave_Config_Default(&config);
    memcpy(config.bind_address, "127.0.0.1", sizeof("127.0.0.1"));
    for (arg = 1; arg < argc; ++arg) {
        unsigned long value; /* 先在宽整数中验证范围，再赋给配置中的较窄字段。 */
        const char *option = argv[arg];
        if (strcmp(option, "--help") == 0) { Example_Usage(argv[0]); return EXIT_SUCCESS; }
        /* 非帮助选项必须有值；此处前进一次取值，for尾部再前进一次到下一个选项。 */
        if (++arg == argc) { Example_Usage(argv[0]); return EXIT_FAILURE; }
        if (strcmp(option, "--bind") == 0) {
            /* 这里只保证固定数组能容纳含NUL的文本，IPv4语法由Slave_Init中的Net后端检查。 */
            if (strlen(argv[arg]) >= sizeof(config.bind_address)) { return EXIT_FAILURE; }
            strcpy(config.bind_address, argv[arg]);
        } else if (strcmp(option, "--port") == 0 && Example_Number(argv[arg], UINT16_MAX, &value)) {
            config.port = (uint16_t)value;
        } else if (strcmp(option, "--ca") == 0 && Example_Number(argv[arg], 65534U, &value) && value != 0U) {
            common_address = (uint16_t)value;
        } else if (strcmp(option, "--window") == 0 &&
                   Example_Number(argv[arg], IEC104_SEQUENCE_MASK, &value) && value != 0U) {
            config.protocol.link.k = (uint16_t)value;
        } else if (strcmp(option, "--run-ms") == 0 && Example_Number(argv[arg], UINT32_MAX, &value)) {
            run_ms = value;
        } else if (strcmp(option, "--clock") == 0 && strcmp(argv[arg], "simulated") == 0) {
            clock_system = false;
        } else if (strcmp(option, "--clock") == 0 && strcmp(argv[arg], "system") == 0) {
            clock_system = true;
        } else {
            fprintf(stderr, "Invalid option/value: %s %s\n", option, argv[arg]);
            return EXIT_FAILURE;
        }
    }
    /* 第2步：取得静态池句柄后绑定应用上下文，再初始化实际网络监听。 */
    slave = IEC104_Slave_Create();
    if (slave == NULL) { fputs("No free Slave service slot\n", stderr); return EXIT_FAILURE; }
    if (!Example_Init(&app, slave, common_address, NULL, 0U)) {
        (void)IEC104_Slave_Destroy(slave, NULL);
        return EXIT_FAILURE;
    }
    if (!Example_Init_Counters(&app, NULL, 0U)) {
        (void)IEC104_Interrogation_Destroy(app.interrogation);
        (void)IEC104_Slave_Remove_Station(slave, &app.station);
        (void)IEC104_Slave_Destroy(slave, NULL);
        return EXIT_FAILURE;
    }
    if (!Example_Init_Clock(&app, NULL)) {
        (void)IEC104_Interrogation_Destroy(app.interrogation);
        (void)IEC104_Interrogation_Destroy(app.counter);
        (void)IEC104_Slave_Remove_Station(slave, &app.station);
        (void)IEC104_Slave_Destroy(slave, NULL);
        return EXIT_FAILURE;
    }
    app.clock_system = clock_system;
    result = IEC104_Slave_Init(slave, &config, &error);
    if (result != IEC104_TCP_OK) {
        fprintf(stderr, "Init failed: result=%d stage=%d socket=%d\n", result, error.stage, error.socket_error);
        /* Init失败仍须释放已创建的业务模块和Slave槽。 */
        (void)IEC104_Interrogation_Destroy(app.interrogation);
        (void)IEC104_Interrogation_Destroy(app.counter);
        (void)IEC104_ClockSynchronization_Destroy(app.clock);
        (void)IEC104_Slave_Remove_Station(slave, &app.station);
        (void)IEC104_Slave_Destroy(slave, NULL);
        return EXIT_FAILURE;
    }
    /* 监听成功后取得系统实际绑定的端口，不能把配置中的0当作可连接端口输出。 */
    if (IEC104_Slave_Get_Status(slave, &status, &error) != IEC104_TCP_OK) {
        exit_code = EXIT_FAILURE;
        goto cleanup;
    }
    /* 第3步：安装仅置标志的信号处理器；真正的资源关闭仍在主线程执行。 */
    (void)signal(SIGINT, Example_Stop);
    (void)signal(SIGTERM, Example_Stop);
    started = GetTickCount64();
    printf("LISTEN %s:%u CA=%u\n", config.bind_address, (unsigned)status.bound_port, (unsigned)common_address);
    fflush(stdout); /* 让终端或通过管道启动本程序的测试立即取得实际监听端点。 */
    while (!example_stop && (run_ms == 0U || GetTickCount64() - started < run_ms)) {
        /* 有待续读通知或可立即提交的任务时安排0等待；WAIT则交回网络循环，等待上限50ms。
         * Poll还会按库内本地工作和协议期限缩短等待；50ms只约束等待，不保证整轮执行耗时。 */
        uint32_t wait_ms = Example_Wait_Time(&app, 50U);
        result = IEC104_Slave_Poll(slave, wait_ms, &error);
        if (result != IEC104_TCP_OK) {
            /* 客户端普通断线由事件表达；这里收到的是服务接口失败，结束循环统一清理。 */
            fprintf(stderr, "Poll failed: result=%d stage=%d socket=%d\n", result, error.stage, error.socket_error);
            exit_code = EXIT_FAILURE;
            break;
        }
        /* 先消费状态变化再推进业务；Drain失败会短路，不继续对不可信状态提交应答。 */
        if (!Example_Drain(&app) || !Example_Step(&app)) {
            fputs("Application event/build failure\n", stderr);
            exit_code = EXIT_FAILURE;
            break;
        }
    }
cleanup:
    /* 第4步：停止应用任务，再结束网络；取消只丢弃尚未提交完毕的任务，不重发已接手数据。 */
    Example_Cancel(&app);
    /* Cancel只将终结通知排队；释放总召实例前必须读完，并清理应用自己的遍历状态及资源。 */
    if (!Example_Drain_Business(&app) || !Example_Drain_Counter(&app)) { exit_code = EXIT_FAILURE; }
    if (IEC104_Slave_Close(slave, &error) != IEC104_TCP_OK) { exit_code = EXIT_FAILURE; }
    {
        IEC104_SlaveEvent_t event;
        IEC104_TcpEventResult_t next;
        /* Close保留收尾通知。对时只消费非I帧状态，不再受理请求或执行动作。 */
        while ((next = IEC104_Slave_NextEvent(slave, &event)) == IEC104_TCP_EVENT_READY) {
            if (app.clock != NULL && event.transport.type != IEC104_TCP_EVENT_I_FRAME &&
                IEC104_ClockSynchronization_Handle_Event(app.clock, &event) ==
                    IEC104_CLOCK_SYNCHRONIZATION_EVENT_ERROR) { exit_code = EXIT_FAILURE; }
        }
        if (next != IEC104_TCP_EVENT_EMPTY) { exit_code = EXIT_FAILURE; }
    }
    if (!IEC104_ClockSynchronization_Get_Status(app.clock, &app.cs)) { exit_code = EXIT_FAILURE; }
    /* 只有关闭且FIFO读空后才能归还槽；清理失败也必须体现在程序退出码中。 */
    if (!IEC104_Interrogation_Destroy(app.interrogation)) { exit_code = EXIT_FAILURE; }
    if (!IEC104_Interrogation_Destroy(app.counter)) { exit_code = EXIT_FAILURE; }
    if (!IEC104_ClockSynchronization_Destroy(app.clock)) { exit_code = EXIT_FAILURE; }
    if (IEC104_Slave_Remove_Station(slave, &app.station) != IEC104_STATION_OK) { exit_code = EXIT_FAILURE; }
    if (IEC104_Slave_Destroy(slave, &error) != IEC104_TCP_OK) { exit_code = EXIT_FAILURE; }
    /* 打印应用提交统计；这些值不用于推断未确认帧是否已到达主站，也不作为自动重试依据。 */
    printf("STOP submitted=%lu gi_submitted=%lu waits=%lu rejected=%lu cancelled=%lu overloads=%lu deactivated=%lu timeouts=%lu negative_submitted=%lu dropped_requests=%lu counter_submitted=%lu counter_completed=%lu clock_executed=%lu clock_synchronized=%lu clock_submitted=%lu\n",
        app.gi.submitted + app.other_submitted, app.gi.gi_submitted, app.gi.waits,
        app.gi.rejected + app.other_rejected, app.gi.cancelled + app.other_cancelled,
        app.gi.overloads + app.other_overloads, app.gi.deactivated, app.gi.timeouts,
        app.gi.negative_submitted, app.gi.dropped_requests + app.other_overloads,
        app.ci.submitted, app.counter_completed, app.cs.executed, app.cs.synchronized, app.cs.submitted);
    return exit_code;
}
#endif