/*
 * cppmain.cc
 *
 *  Created on: Jul 4, 2023
 *      Author: heck
 */

#include "cppmain.h"
#include "main.h"
#include "usbd_cdc_if.h"
#include <cmath>
#include "limits"

const double pi{ std::acos(-1) };


namespace Heck {
    // Serial Logging
    // --------------
    void log(const std::string &msg)
    {
        std::string out{ msg };
        out.append("\r\n");
        CDC_Transmit_FS((uint8_t *)out.data(), out.size());
    }


// DAC
// ---
#define BUFFER_SIZE 128
    u32 audio_buffer[BUFFER_SIZE];
    //    u32 audio_buffer[BUFFER_SIZE] = {
    //        2048, 2149, 2250, 2350, 2450, 2549, 2646, 2742, 2837, 2929, 3020, 3108, 3193, 3275, 3355,
    //        3431, 3504, 3574, 3639, 3701, 3759, 3812, 3861, 3906, 3946, 3982, 4013, 4039, 4060, 4076,
    //        4087, 4094, 4095, 4091, 4082, 4069, 4050, 4026, 3998, 3965, 3927, 3884, 3837, 3786, 3730,
    //        3671, 3607, 3539, 3468, 3394, 3316, 3235, 3151, 3064, 2975, 2883, 2790, 2695, 2598, 2500,
    //        2400, 2300, 2199, 2098, 1997, 1896, 1795, 1695, 1595, 1497, 1400, 1305, 1212, 1120, 1031,
    //        944,  860,  779,  701,  627,  556,  488,  424,  365,  309,  258,  211,  168,  130,  97,
    //        69,   45,   26,   13,   4,    0,    1,    8,    19,   35,   56,   82,   113,  149,  189,
    //        234,  283,  336,  394,  456,  521,  591,  664,  740,  820,  902,  987,  1075, 1166, 1258,
    //        1353, 1449, 1546, 1645, 1745, 1845, 1946, 2047
    //    };

    void dac1_set(u32 val)
    {
        HAL_DAC_SetValue(&hdac_global, DAC_CHANNEL_1, DAC_ALIGN_12B_R, val);
    }

    void dac1_toggle()
    {
        static bool dac_state{ 0 };
        dac_state = !dac_state;
        if (dac_state) {
            dac1_set(0b0000111111111111);
        } else {
            dac1_set(0b0000000000000000);
        }
    }

    void dac_start_dma()
    {
        HAL_DAC_Start_DMA(&hdac_global, DAC_CHANNEL_1, (u32 *)audio_buffer, BUFFER_SIZE, DAC_ALIGN_12B_R);
    }

    void dac_stop_dma()
    {
        HAL_DAC_Stop_DMA(&hdac_global, DAC_CHANNEL_1);
    }

    // LED
    // ---

    void led_green_toggle()
    {
        HAL_GPIO_TogglePin(LED_GREEN_GPIO_Port, LED_GREEN_Pin);
    }

    void led_green_on()
    {
        HAL_GPIO_WritePin(LED_GREEN_GPIO_Port, LED_GREEN_Pin, GPIO_PIN_SET);
    }

    void led_green_off()
    {
        HAL_GPIO_WritePin(LED_GREEN_GPIO_Port, LED_GREEN_Pin, GPIO_PIN_RESET);
    }


    // CALLBACKS
    void irq1_cb()
    {
        if (!is_running) {
            is_running = true;
            return;
        }
    }

    void timer2_cb()
    {
        led_green_toggle();
    }

    void timer7_cb() {}

    // dont forget to start the DAC
    // HAL_DAC_Start(&hdac, DAC_CHANNEL_1);
    void bytebeat()
    {
        long t{ 0 };
        while (true) {
            unsigned char res = t * ((t >> 12 | t >> 8) & 63 & t >> 4);
            dac1_set((res % 256) * 100);
            for (int g = 0; g < 60000; g++) {}
            t++;
            t %= (std::numeric_limits<long>::max() - 1);
        }
    }

    u32 random(u32 max)
    {
        u32 ret{ 0 };
        HAL_RNG_GenerateRandomNumber(&hrng, &ret);
        ret %= max;
        return ret;
    }

    void init_buffer_noise()
    {
        log("init_buffer_noise()");
        for (int i = 0; i < BUFFER_SIZE; i++) {
            u32 val = random(4096);
            audio_buffer[i] = val;
            log(std::to_string(val));
        }
    }

    void init_buffer_sin()
    {
        log("init_buffer_sin()");
        for (int i = 0; i < BUFFER_SIZE; i++) {
            float p = float(i) / (float)BUFFER_SIZE - 0.5;
            u32 val = sin(p) * 4096;
            audio_buffer[i] = val;
            log(std::to_string(val));
        }
    }

    void noisify_buffer()
    {
        u32 buf_index = random(BUFFER_SIZE);
        u32 buf_val = random(4096);
        audio_buffer[buf_index] = buf_val;
        log("i:" + std::to_string(buf_index) + " v:" + std::to_string(buf_val));
    }

    void main()
    {
        //        while (!is_running) {
        //            HAL_Delay(1);
        //        }
        log("Starting...");

        dac_start_dma();

        HAL_TIM_Base_Start_IT(&htim2);
        HAL_TIM_Base_Start_IT(&htim7);
        HAL_TIM_Base_Start(&htim6);

        //                init_buffer_noise();
        init_buffer_sin();
        log("Entering MainLoop...");
        while (true) {
            noisify_buffer();
            HAL_Delay(10);
        }
    }

} // namespace Heck


// ----------------------------------------------------------------------------------------------
// C Linkage (Bridging)
// ----------------------------------------------------------------------------------------------

void HAL_GPIO_EXTI_Callback(uint16_t GPIO_Pin)
{
    if (GPIO_Pin == BUT_BLUE_Pin) {
        Heck::irq1_cb();
    } else {
        __NOP(); // why NOP? i dont know! was from an example
    }
}

void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim)
{
    if (htim->Instance == TIM2) {
        Heck::log(
            "TIM2 timer: instance: " + std::to_string(reinterpret_cast<u32>(htim->Instance)) +
            " channel: " + std::to_string(htim->Channel));
        Heck::timer2_cb();
    } else if (htim->Instance == TIM6) {
        Heck::log(
            "TIM6 timer: instance: " + std::to_string(reinterpret_cast<u32>(htim->Instance)) +
            " channel: " + std::to_string(htim->Channel));
    } else if (htim->Instance == TIM7) {
        Heck::log(
            "TIM7 timer: instance: " + std::to_string(reinterpret_cast<u32>(htim->Instance)) +
            " channel: " + std::to_string(htim->Channel));
        Heck::timer7_cb();
    } else {
        Heck::log(
            "UNKNOWN timer: instance: " + std::to_string(reinterpret_cast<u32>(htim->Instance)) +
            " channel: " + std::to_string(htim->Channel));
    }
}


void HAL_DAC_ConvCpltCallbackCh1(DAC_HandleTypeDef *hdac)
{
    Heck::dac_start_dma();
}

void heck_error_handler()
{
    Heck::log("HECK ERRRRROR HANDLER");
}

void heck_cppmain(void)
{
    Heck::main();
}