/*
 * IOTC Bridge — ARM32 process that loads the TUTK library and
 * communicates with the Python TUI over stdin/stdout JSON.
 *
 * Compile: arm-linux-gnueabi-gcc -o iotc_bridge iotc_bridge.c -L../lib -lIOTCAPIs_ALL -lpthread -ldl
 * Run:     qemu-arm-static -L /usr/arm-linux-gnueabi ./iotc_bridge
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <pthread.h>

/* IOTC API declarations (from IOTCAPIs.h) */
extern int IOTC_Initialize2(int udp_port);
extern int IOTC_DeInitialize(void);
extern int IOTC_Get_SessionID(void);
extern int IOTC_Connect_ByUID_Parallel(const char *UID, int SID);
extern int IOTC_Session_Close(int SID);
extern int IOTC_Session_Check(int SID, void *info);
extern int IOTC_Lan_Search2(void *result, int max, int timeout_ms);

/* AV API declarations (from AVAPIs.h) */
extern int avInitialize(int max_channels);
extern int avDeInitialize(void);
extern int avClientStart(int SID, const char *user, const char *pass,
                         int timeout, unsigned int *srvtype, int channel);
extern void avClientStop(int avIndex);
extern int avSendIOCtrl(int avIndex, int type, const char *data, int len);
extern int avRecvIOCtrl(int avIndex, int *type, char *data, int len, int timeout_ms);

/* Simple JSON output helpers */
static void json_ok(const char *key, int value) {
    printf("{\"ok\":true,\"%s\":%d}\n", key, value);
    fflush(stdout);
}

static void json_ok_str(const char *key, const char *value) {
    printf("{\"ok\":true,\"%s\":\"%s\"}\n", key, value);
    fflush(stdout);
}

static void json_err(const char *msg) {
    printf("{\"ok\":false,\"error\":\"%s\"}\n", msg);
    fflush(stdout);
}

static void json_data(const char *cmd, const unsigned char *data, int len) {
    printf("{\"ok\":true,\"cmd\":\"%s\",\"len\":%d,\"hex\":\"", cmd, len);
    for (int i = 0; i < len && i < 4096; i++)
        printf("%02x", data[i]);
    printf("\"}\n");
    fflush(stdout);
}

/* State */
static int g_sid = -1;
static int g_av_index = -1;
static int g_initialized = 0;

static int do_init(void) {
    if (g_initialized) {
        json_err("already initialized");
        return -1;
    }
    int ret = IOTC_Initialize2(0);
    if (ret < 0) {
        char buf[64];
        snprintf(buf, sizeof(buf), "IOTC_Initialize2 failed: %d", ret);
        json_err(buf);
        return ret;
    }
    ret = avInitialize(16);
    if (ret < 0) {
        char buf[64];
        snprintf(buf, sizeof(buf), "avInitialize failed: %d", ret);
        json_err(buf);
        return ret;
    }
    g_initialized = 1;
    json_ok("init", 0);
    return 0;
}

static int do_connect(const char *uid) {
    if (!g_initialized) {
        json_err("not initialized");
        return -1;
    }
    int sid = IOTC_Get_SessionID();
    if (sid < 0) {
        char buf[64];
        snprintf(buf, sizeof(buf), "IOTC_Get_SessionID failed: %d", sid);
        json_err(buf);
        return sid;
    }
    g_sid = IOTC_Connect_ByUID_Parallel(uid, sid);
    if (g_sid < 0) {
        char buf[64];
        snprintf(buf, sizeof(buf), "connect failed: %d", g_sid);
        json_err(buf);
        return g_sid;
    }
    json_ok("sid", g_sid);
    return g_sid;
}

static int do_login(const char *user, const char *pass) {
    if (g_sid < 0) {
        json_err("not connected");
        return -1;
    }
    unsigned int srvtype = 0;
    g_av_index = avClientStart(g_sid, user, pass, 20, &srvtype, 0);
    if (g_av_index < 0) {
        char buf[64];
        snprintf(buf, sizeof(buf), "avClientStart failed: %d", g_av_index);
        json_err(buf);
        return g_av_index;
    }
    json_ok("av_index", g_av_index);
    return g_av_index;
}

static int do_ioctrl(int cmd_type, const char *hex_data) {
    if (g_av_index < 0) {
        json_err("not logged in");
        return -1;
    }

    /* Parse hex data */
    int hex_len = strlen(hex_data);
    int data_len = hex_len / 2;
    unsigned char *data = calloc(1, data_len + 1);
    for (int i = 0; i < data_len; i++) {
        unsigned int byte;
        sscanf(hex_data + i * 2, "%2x", &byte);
        data[i] = (unsigned char)byte;
    }

    int ret = avSendIOCtrl(g_av_index, cmd_type, (const char *)data, data_len);
    free(data);

    if (ret < 0) {
        char buf[64];
        snprintf(buf, sizeof(buf), "avSendIOCtrl failed: %d", ret);
        json_err(buf);
        return ret;
    }

    /* Try to receive response */
    unsigned char resp[8192];
    int resp_type = 0;
    int resp_len = avRecvIOCtrl(g_av_index, &resp_type, (char *)resp, sizeof(resp), 5000);
    if (resp_len > 0) {
        json_data("ioctrl_resp", resp, resp_len);
    } else {
        json_ok("sent", cmd_type);
    }
    return 0;
}

static int do_lan_search(void) {
    if (!g_initialized) {
        json_err("not initialized");
        return -1;
    }
    /* Search result struct: 84 bytes per entry (UID[20] + IP[16] + ...)] */
    unsigned char results[84 * 16];
    memset(results, 0, sizeof(results));
    int count = IOTC_Lan_Search2(results, 16, 3000);
    if (count < 0) {
        char buf[64];
        snprintf(buf, sizeof(buf), "lan_search failed: %d", count);
        json_err(buf);
        return count;
    }
    printf("{\"ok\":true,\"count\":%d,\"devices\":[", count);
    for (int i = 0; i < count; i++) {
        unsigned char *entry = results + (i * 84);
        char uid[21] = {0};
        memcpy(uid, entry, 20);
        if (i > 0) printf(",");
        printf("\"%s\"", uid);
    }
    printf("]}\n");
    fflush(stdout);
    return count;
}

static void do_disconnect(void) {
    if (g_av_index >= 0) {
        avClientStop(g_av_index);
        g_av_index = -1;
    }
    if (g_sid >= 0) {
        IOTC_Session_Close(g_sid);
        g_sid = -1;
    }
    json_ok("disconnected", 1);
}

static void do_deinit(void) {
    do_disconnect();
    if (g_initialized) {
        avDeInitialize();
        IOTC_DeInitialize();
        g_initialized = 0;
    }
    json_ok("deinit", 1);
}

int main(int argc, char *argv[]) {
    char line[8192];

    fprintf(stderr, "IOTC Bridge started. Send JSON commands on stdin.\n");

    while (fgets(line, sizeof(line), stdin)) {
        /* Strip newline */
        line[strcspn(line, "\r\n")] = 0;
        if (strlen(line) == 0) continue;

        /* Very simple command parsing: cmd arg1 arg2 ... */
        char cmd[64] = {0};
        char arg1[256] = {0};
        char arg2[256] = {0};
        char arg3[8192] = {0};
        sscanf(line, "%63s %255s %255s %8191s", cmd, arg1, arg2, arg3);

        if (strcmp(cmd, "init") == 0) {
            do_init();
        } else if (strcmp(cmd, "connect") == 0) {
            if (strlen(arg1) == 0) {
                json_err("usage: connect <UID>");
            } else {
                do_connect(arg1);
            }
        } else if (strcmp(cmd, "login") == 0) {
            if (strlen(arg1) == 0 || strlen(arg2) == 0) {
                json_err("usage: login <user> <pass>");
            } else {
                do_login(arg1, arg2);
            }
        } else if (strcmp(cmd, "ioctrl") == 0) {
            if (strlen(arg1) == 0) {
                json_err("usage: ioctrl <cmd_id> [hex_data]");
            } else {
                int cmd_id = atoi(arg1);
                do_ioctrl(cmd_id, strlen(arg2) > 0 ? arg2 : "");
            }
        } else if (strcmp(cmd, "search") == 0) {
            do_lan_search();
        } else if (strcmp(cmd, "disconnect") == 0) {
            do_disconnect();
        } else if (strcmp(cmd, "quit") == 0 || strcmp(cmd, "exit") == 0) {
            do_deinit();
            break;
        } else if (strcmp(cmd, "help") == 0) {
            printf("{\"commands\":[\"init\",\"connect <UID>\",\"login <user> <pass>\",\"ioctrl <cmd_id> [hex]\",\"search\",\"disconnect\",\"quit\"]}\n");
            fflush(stdout);
        } else {
            json_err("unknown command");
        }
    }

    do_deinit();
    return 0;
}