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

#include <freertos/FreeRTOS.h>
#include <freertos/task.h>

#include <esp_timer.h>
#include <esp_log.h>

#include "eos.h"
#include "net.h"
#include "at_cmd.h"
#include "cell.h"

static const char *TAG = "EOS CELL VOICE";

extern char *at_cmd_buf;

void eos_cell_voice_handler(unsigned char _mtype, EOSMessage *msg, uint16_t len) {
    unsigned char mtype;
    unsigned char *buffer = msg->buffer;
    int rv;

    if (len < 1) return;

    mtype = buffer[0] & ~EOS_CELL_MTYPE_MASK;
    buffer++;
    len--;

    switch (mtype) {
        case EOS_CELL_MTYPE_VOICE_DIAL: {
            if (len > EOS_CELL_SIZE_PHNUM) break;

            rv = snprintf(at_cmd_buf, AT_SIZE_CMD_BUF, "ATD%.*s;\r", len, buffer);
            if ((rv < 0) || (rv >= AT_SIZE_CMD_BUF)) break;

            rv = eos_modem_take(1000);
            if (rv) break;

            at_cmd(at_cmd_buf);
            rv = at_expect("^OK", "^(ERROR|\\+CME ERROR: [0-9]+)", 1000);

            eos_modem_give();
            eos_cell_pcm_start();
            break;
        }

        case EOS_CELL_MTYPE_VOICE_ANSWER: {
            rv = eos_modem_take(1000);
            if (rv) break;

            at_cmd("ATA\r");
            // Response will be picked up by urc handler

            eos_modem_give();
            eos_cell_pcm_start();
            break;
        }

        case EOS_CELL_MTYPE_VOICE_HANGUP: {
            eos_cell_pcm_stop();

            rv = eos_modem_take(1000);
            if (rv) break;

            at_cmd("AT+CHUP\r");
            // Response will be picked up by urc handler

            eos_modem_give();
            break;
        }

        case EOS_CELL_MTYPE_VOICE_PCM: {
            eos_cell_pcm_push(buffer, len);
            break;
        }
    }
}

static void ring_handler(char *urc, regmatch_t m[]) {
    EOSMessage msg;
    uint16_t len;
    char *buffer;
    regmatch_t match[2];
    int rv = EOS_OK;

    eos_net_alloc(&msg);
    if (msg.size < EOS_CELL_SIZE_PHNUM + 1) {
        eos_net_free(&msg);
        return;
    }
    msg.buffer[0] = EOS_CELL_MTYPE_VOICE | EOS_CELL_MTYPE_VOICE_RING;
    len = 1;
    rv = at_expect_match("^\\+CLIP: \"(\\+?[0-9]+)\"", NULL, &buffer, match, 2, REG_EXTENDED, 1000);
    if (!rv) {
        regoff_t num_len;

        num_len = match[1].rm_eo - match[1].rm_so;
        if (num_len > EOS_CELL_SIZE_PHNUM) {
            eos_net_free(&msg);
            return;
        }
        memcpy(msg.buffer + 1, buffer + match[1].rm_so, num_len);
        len += num_len;
    }
    rv = eos_net_send(EOS_NET_MTYPE_CELL, &msg, len);
    if (rv) ESP_LOGE(TAG, "NET SEND ERR:%d", rv);
}

static void busy_handler(char *urc, regmatch_t m[]) {
    EOSMessage msg;
    int rv;

    eos_cell_pcm_stop();

    eos_net_alloc(&msg);
    if (msg.size < 1) {
        eos_net_free(&msg);
        return;
    }
    msg.buffer[0] = EOS_CELL_MTYPE_VOICE | EOS_CELL_MTYPE_VOICE_BUSY;
    rv = eos_net_send(EOS_NET_MTYPE_CELL, &msg, 1);
    if (rv) ESP_LOGE(TAG, "NET SEND ERR:%d", rv);
}

static void miss_handler(char *urc, regmatch_t m[]) {
    EOSMessage msg;
    int rv;

    eos_cell_pcm_stop();

    eos_net_alloc(&msg);
    if (msg.size < 1) {
        eos_net_free(&msg);
        return;
    }
    msg.buffer[0] = EOS_CELL_MTYPE_VOICE | EOS_CELL_MTYPE_VOICE_MISS;
    rv = eos_net_send(EOS_NET_MTYPE_CELL, &msg, 1);
    if (rv) ESP_LOGE(TAG, "NET SEND ERR:%d", rv);
}

static void call_begin_handler(char *urc, regmatch_t m[]) {
    EOSMessage msg;
    int rv;

    eos_net_alloc(&msg);
    if (msg.size < 1) {
        eos_net_free(&msg);
        return;
    }

    vTaskDelay(100 / portTICK_PERIOD_MS);
    at_cmd("AT+CECH=0x0000\r");
    at_expect("^OK", "^ERROR", 1000);

    at_cmd("AT+CECDT=0x0000\r");
    at_expect("^OK", "^ERROR", 1000);

    at_cmd("AT+CECWB=0x0000\r");
    at_expect("^OK", "^ERROR", 1000);

    at_cmd("AT+CNSLIM=0x0000\r");
    at_expect("^OK", "^ERROR", 1000);
    /*
    at_cmd("AT+CECRX=0\r");
    at_expect("^OK", "^ERROR", 1000);
    */

    msg.buffer[0] = EOS_CELL_MTYPE_VOICE | EOS_CELL_MTYPE_VOICE_BEGIN;
    rv = eos_net_send(EOS_NET_MTYPE_CELL, &msg, 1);
    if (rv) ESP_LOGE(TAG, "NET SEND ERR:%d", rv);
}

static void call_end_handler(char *urc, regmatch_t m[]) {
    EOSMessage msg;
    int duration = 0;
    int rv;

    eos_cell_pcm_stop();

    eos_net_alloc(&msg);
    if (msg.size < 5) {
        eos_net_free(&msg);
        return;
    }

    sscanf(urc + m[1].rm_so, "%6d", &duration);
    msg.buffer[0] = EOS_CELL_MTYPE_VOICE | EOS_CELL_MTYPE_VOICE_END;
    msg.buffer[1] = duration >> 24;
    msg.buffer[2] = duration >> 16;
    msg.buffer[3] = duration >> 8;
    msg.buffer[4] = duration;
    rv = eos_net_send(EOS_NET_MTYPE_CELL, &msg, 5);
    if (rv) ESP_LOGE(TAG, "NET SEND ERR:%d", rv);
}

void eos_cell_voice_init(void) {
    int rv;

    rv = at_urc_insert("^RING", ring_handler, REG_EXTENDED);
    assert(rv == EOS_OK);

    rv = at_urc_insert("^BUSY", busy_handler, REG_EXTENDED);
    assert(rv == EOS_OK);

    rv = at_urc_insert("^NO CARRIER", miss_handler, REG_EXTENDED);
    assert(rv == EOS_OK);

    rv = at_urc_insert("^MISSED.CALL: [^ ]+ (\\+?[0-9]+)$", miss_handler, REG_EXTENDED);
    assert(rv == EOS_OK);

    rv = at_urc_insert("^VOICE CALL: BEGIN", call_begin_handler, REG_EXTENDED);
    assert(rv == EOS_OK);

    rv = at_urc_insert("^VOICE CALL: END: ([0-9]{6}$)$", call_end_handler, REG_EXTENDED);
    assert(rv == EOS_OK);

}