/*
 * ESP8266 WiFi模块驱动（支持HTTP加密传输）
 * 新增功能：
 * 1. HTTP POST请求支持
 * 2. 加密数据传输
 * 3. 自动重连机制
 */

#include "esp8266.h"
#include "Serial.h"
#include "Delay.h"
#include <stdio.h>
#include <string.h>

// 外部配置（在main.c中定义）
extern const char* WIFI_SSID;
extern const char* WIFI_PASSWORD;
extern const char* HTTP_SERVER_IP;
extern const char* HTTP_SERVER_PORT;
extern const char* HTTP_API_TOKEN;

// 内部函数声明
static uint8_t ESP8266_SendCommand(const char* cmd, const char* expected, uint16_t timeout);
static void ESP8266_ClearBuffer(void);

/**
 * @brief 发送AT命令并等待响应
 */
static uint8_t ESP8266_SendCommand(const char* cmd, const char* expected, uint16_t timeout)
{
    Serial_SendString(cmd);
    Serial_SendString("\r\n");

    Delay_ms(timeout);

    if (expected == NULL) {
        return ESP8266_SUCCESS;
    }

    // 检查是否收到期望的响应
    char* response = Serial_GetRxData();
    if (strstr(response, expected) != NULL) {
        return ESP8266_SUCCESS;
    }

    return ESP8266_FAIL;
}

static void ESP8266_ClearBuffer(void)
{
    Serial_ClearRxBuffer();
}

uint8_t ESP8266_Setup(void)
{
    ESP8266_ClearBuffer();

    // 测试AT指令
    if (ESP8266_SendCommand("AT", "OK", 1000) == ESP8266_FAIL) {
        return ESP8266_FAIL;
    }

    // 设置为STA模式（客户端模式）
    if (ESP8266_SendCommand("AT+CWMODE=1", "OK", 1000) == ESP8266_FAIL) {
        return ESP8266_FAIL;
    }

    // 关闭回显
    ESP8266_SendCommand("ATE0", "OK", 500);

    // 设置单连接模式
    if (ESP8266_SendCommand("AT+CIPMUX=0", "OK", 1000) == ESP8266_FAIL) {
        return ESP8266_FAIL;
    }

    return ESP8266_SUCCESS;
}

uint8_t ESP8266_ConnectWiFi(const char* ssid, const char* password)
{
    char cmd[128];

    ESP8266_ClearBuffer();

    // 断开之前的WiFi连接
    ESP8266_SendCommand("AT+CWQAP", "OK", 1000);
    Delay_ms(1000);

    // 连接到WiFi
    sprintf(cmd, "AT+CWJAP=\"%s\",\"%s\"", ssid, password);

    // WiFi连接可能需要较长时间
    if (ESP8266_SendCommand(cmd, "OK", 10000) == ESP8266_FAIL) {
        return ESP8266_FAIL;
    }

    Delay_ms(2000);
    return ESP8266_SUCCESS;
}

uint8_t ESP8266_ConnectHTTPServer(const char* ip, const char* port)
{
    char cmd[64];

    ESP8266_ClearBuffer();

    // 断开之前的TCP连接
    ESP8266_SendCommand("AT+CIPCLOSE", "OK", 1000);
    Delay_ms(500);

    // 建立TCP连接到HTTP服务器
    sprintf(cmd, "AT+CIPSTART=\"TCP\",\"%s\",%s", ip, port);

    if (ESP8266_SendCommand(cmd, "OK", 5000) == ESP8266_FAIL) {
        return ESP8266_FAIL;
    }

    Delay_ms(1000);
    return ESP8266_SUCCESS;
}

uint8_t ESP8266_SendEncryptedData(const char* encrypted_data)
{
    char http_request[1024];
    char cmd[32];
    uint32_t content_length = strlen(encrypted_data);

    // 构建HTTP POST请求
    sprintf(http_request,
        "POST /api/v1/attendance/checkins HTTP/1.1\r\n"
        "Host: %s:%s\r\n"
        "Content-Type: application/octet-stream\r\n"
        "X-Api-Token: %s\r\n"
        "X-Encrypted: AES128-CBC\r\n"
        "Content-Length: %u\r\n"
        "Connection: keep-alive\r\n"
        "\r\n"
        "%s",
        HTTP_SERVER_IP,
        HTTP_SERVER_PORT,
        HTTP_API_TOKEN,
        content_length,
        encrypted_data
    );

    uint32_t request_len = strlen(http_request);

    // 发送数据长度命令
    sprintf(cmd, "AT+CIPSEND=%u", request_len);

    ESP8266_ClearBuffer();

    if (ESP8266_SendCommand(cmd, ">", 2000) == ESP8266_FAIL) {
        return ESP8266_FAIL;
    }

    // 发送HTTP请求
    Serial_SendString(http_request);

    // 等待发送完成（不阻塞太久）
    Delay_ms(100);

    // 可选：等待服务器响应（检查是否有"200 OK"）
    // 但为了不阻塞，建议不等待

    return ESP8266_SUCCESS;
}

uint8_t ESP8266_CheckConnection(void)
{
    ESP8266_ClearBuffer();

    if (ESP8266_SendCommand("AT+CIPSTATUS", "OK", 1000) == ESP8266_FAIL) {
        return ESP8266_FAIL;
    }

    // 检查响应中是否包含"STATUS:3"（已连接）
    char* response = Serial_GetRxData();
    if (strstr(response, "STATUS:3") != NULL ||
        strstr(response, "STATUS:4") != NULL) {
        return ESP8266_SUCCESS;
    }

    return ESP8266_FAIL;
}

uint8_t ESP8266_GetNetworkTime(ESP8266_DateTime* datetime)
{
    // 启用SNTP
    if (ESP8266_SendCommand("AT+CIPSNTPCFG=1,8,\"pool.ntp.org\"", "OK", 2000) == ESP8266_FAIL) {
        return ESP8266_FAIL;
    }

    Delay_ms(3000); // 等待时间同步

    ESP8266_ClearBuffer();

    // 获取时间
    if (ESP8266_SendCommand("AT+CIPSNTPTIME?", "OK", 1000) == ESP8266_FAIL) {
        return ESP8266_FAIL;
    }

    // 解析响应（格式：+CIPSNTPTIME:Thu Jan 01 08:00:00 2024）
    char* response = Serial_GetRxData();
    char* time_str = strstr(response, "+CIPSNTPTIME:");

    if (time_str != NULL) {
        // 简单解析（这里只是示例，实际需要更完善的解析）
        sscanf(time_str, "+CIPSNTPTIME:%*s %*s %d %d:%d:%d %d",
               &datetime->day, &datetime->hour,
               &datetime->minute, &datetime->second, &datetime->year);

        return ESP8266_SUCCESS;
    }

    return ESP8266_FAIL;
}

// ========== 兼容旧版本的函数（已废弃） ==========

uint8_t ESP8266_ConnectTCPServer(const char* ip, const char* port)
{
    // 重定向到HTTP版本
    return ESP8266_ConnectHTTPServer(ip, port);
}

uint8_t ESP8266_SendData(char* Data)
{
    // 警告：此函数已废弃，请使用ESP8266_SendEncryptedData
    // 为了兼容，这里保留基本实现
    char cmd[32];

    sprintf(cmd, "AT+CIPSEND=%d", strlen(Data));

    if (ESP8266_SendCommand(cmd, ">", 2000) == ESP8266_FAIL) {
        return ESP8266_FAIL;
    }

    Serial_SendString(Data);
    Delay_ms(50);

    return ESP8266_SUCCESS;
}