/**
 * @file datarouter.c
 * @brief 数据路由库 —— 实现
 *
 * 端口表：固定大小数组，每个端口存储报文类型 + handler 列表。
 * 发送触发函数逐一调用端口上注册的全部 handler，实现一对多广播。
 */

#include "datarouter.h"
#include <string.h>
#include <stdio.h>

#if defined(__GNUC__) || defined(__clang__)
#define DATAROUTER_WEAK __attribute__((weak))
#else
#define DATAROUTER_WEAK
#endif

#ifndef DATAROUTER_MAX_PORTS
#define DATAROUTER_MAX_PORTS 64
#endif

/**
 * @struct port_entry_t
 * @brief 端口表条目
 *
 * @var type     报文类型（DATAROUTER_CHANNEL_xxx / -1）
 * @var handlers 外设发送 handler 数组
 * @var count    当前注册的 handler 数量
 * @var in_use   1=已分配，0=空闲
 */
typedef struct {
    int                       type;
    datarouter_send_handler_t handlers[DATAROUTER_MAX_HANDLERS_PER_PORT];
    int                       count;
    uint8_t                   in_use;
} port_entry_t;

static port_entry_t ports[DATAROUTER_MAX_PORTS];
static uint8_t      initialized;

/* ---- 通道元数据（X-macro 展开） ---- */

static const char *channel_names[] = {
#define DATAROUTER_CHANNEL(id, desc) #id,
    DATAROUTER_CHANNELS
#undef DATAROUTER_CHANNEL
};

static const char *channel_descs[] = {
#define DATAROUTER_CHANNEL(id, desc) desc,
    DATAROUTER_CHANNELS
#undef DATAROUTER_CHANNEL
};

/* ---- 弱符号接收回调默认实现 ---- */

#define DATAROUTER_CHANNEL(id, desc) \
    DATAROUTER_WEAK void datarouter_on_recv_##id( \
        uint32_t port_id, const void *data, size_t len) \
    { \
        (void)port_id; (void)data; (void)len; \
    }
DATAROUTER_CHANNELS
#undef DATAROUTER_CHANNEL

/* ---- 发送触发函数实现 ---- */

#define DATAROUTER_CHANNEL(id, desc) \
    int datarouter_send_##id(uint32_t port_id, const void *data, size_t len) \
    { \
        if (!initialized) return -1; \
        if (port_id >= DATAROUTER_MAX_PORTS || !ports[port_id].in_use) return -2; \
        if (ports[port_id].type != DATAROUTER_CHANNEL_##id) return -3; \
        if (ports[port_id].count == 0) return -4; \
        for (int _i = 0; _i < ports[port_id].count; _i++) \
            ports[port_id].handlers[_i](port_id, data, len); \
        return 0; \
    }
DATAROUTER_CHANNELS
#undef DATAROUTER_CHANNEL

/* ---- 端口管理 API ---- */

void datarouter_init(void)
{
    if (initialized) return;
    memset(ports, 0, sizeof(ports));
    initialized = 1;
}

void datarouter_reset(void)
{
    initialized = 0;
    memset(ports, 0, sizeof(ports));
}

datarouter_port_t datarouter_port_create(void)
{
    if (!initialized) return DATAROUTER_INVALID_PORT;
    for (int i = 0; i < DATAROUTER_MAX_PORTS; i++) {
        if (!ports[i].in_use) {
            ports[i].in_use  = 1;
            ports[i].type    = -1;
            ports[i].count   = 0;
            return (datarouter_port_t)i;
        }
    }
    return DATAROUTER_INVALID_PORT;
}

void datarouter_port_delete(datarouter_port_t port)
{
    if (!initialized) return;
    if (port < 0 || port >= DATAROUTER_MAX_PORTS) return;
    ports[port].in_use = 0;
}

void datarouter_port_set_type(datarouter_port_t port, int channel_id)
{
    if (!initialized) return;
    if (port < 0 || port >= DATAROUTER_MAX_PORTS || !ports[port].in_use) return;
    ports[port].type = channel_id;
}

int datarouter_port_get_type(datarouter_port_t port)
{
    if (!initialized) return -1;
    if (port < 0 || port >= DATAROUTER_MAX_PORTS || !ports[port].in_use) return -1;
    return ports[port].type;
}

int datarouter_port_add_handler(datarouter_port_t port, datarouter_send_handler_t handler)
{
    if (!initialized) return -1;
    if (port < 0 || port >= DATAROUTER_MAX_PORTS || !ports[port].in_use) return -1;
    if (ports[port].count >= DATAROUTER_MAX_HANDLERS_PER_PORT) return -2;
    for (int i = 0; i < ports[port].count; i++)
        if (ports[port].handlers[i] == handler) return -3;
    ports[port].handlers[ports[port].count++] = handler;
    return 0;
}

int datarouter_port_remove_handler(datarouter_port_t port, datarouter_send_handler_t handler)
{
    if (!initialized) return -1;
    if (port < 0 || port >= DATAROUTER_MAX_PORTS || !ports[port].in_use) return -1;
    for (int i = 0; i < ports[port].count; i++) {
        if (ports[port].handlers[i] == handler) {
            ports[port].handlers[i] = ports[port].handlers[--ports[port].count];
            return 0;
        }
    }
    return -2;
}

void datarouter_port_clear_handlers(datarouter_port_t port)
{
    if (!initialized) return;
    if (port < 0 || port >= DATAROUTER_MAX_PORTS || !ports[port].in_use) return;
    ports[port].count = 0;
}

int datarouter_port_handler_count(datarouter_port_t port)
{
    if (!initialized) return -1;
    if (port < 0 || port >= DATAROUTER_MAX_PORTS || !ports[port].in_use) return -1;
    return ports[port].count;
}

/* ---- 通道元数据查询 ---- */

int datarouter_channel_count(void)
{
    return DATAROUTER_CHANNEL_COUNT;
}

const char *datarouter_channel_name(int channel_id)
{
    if (channel_id < 0 || channel_id >= DATAROUTER_CHANNEL_COUNT) return NULL;
    return channel_names[channel_id];
}

const char *datarouter_channel_desc(int channel_id)
{
    if (channel_id < 0 || channel_id >= DATAROUTER_CHANNEL_COUNT) return NULL;
    return channel_descs[channel_id];
}