/*
 * This file is part of the MicroPython project, http://micropython.org/
 *
 * The MIT License (MIT)
 *
 * Copyright (c) 2013-2015 Damien P. George
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#include <stdio.h>

#include "modmachine.h"
#include "py/gc.h"
#include "py/runtime.h"
#include "py/mphal.h"
#include "lib/fatfs/ff.h"
#include "lib/fatfs/diskio.h"
#include "gccollect.h"
#include "irq.h"
#include "rng.h"
#include "storage.h"
#include "pin.h"
#include "timer.h"
#include "usb.h"
#include "i2c.h"
#include "spi.h"

// machine.info([dump_alloc_table])
// Print out lots of information about the board.
STATIC mp_obj_t machine_info(mp_uint_t n_args, const mp_obj_t *args) {
    // get and print unique id; 96 bits
    {
        byte *id = (byte*)MP_HAL_UNIQUE_ID_ADDRESS;
        printf("ID=%02x%02x%02x%02x:%02x%02x%02x%02x:%02x%02x%02x%02x\n", id[0], id[1], id[2], id[3], id[4], id[5], id[6], id[7], id[8], id[9], id[10], id[11]);
    }

    // get and print clock speeds
    // SYSCLK=168MHz, HCLK=168MHz, PCLK1=42MHz, PCLK2=84MHz
    {
        printf("S=%lu\nH=%lu\nP1=%lu\nP2=%lu\n",
               HAL_RCC_GetSysClockFreq(),
               HAL_RCC_GetHCLKFreq(),
               HAL_RCC_GetPCLK1Freq(),
               HAL_RCC_GetPCLK2Freq());
    }

    // to print info about memory
    {
        printf("_etext=%p\n", &_etext);
        printf("_sidata=%p\n", &_sidata);
        printf("_sdata=%p\n", &_sdata);
        printf("_edata=%p\n", &_edata);
        printf("_sbss=%p\n", &_sbss);
        printf("_ebss=%p\n", &_ebss);
        printf("_estack=%p\n", &_estack);
        printf("_ram_start=%p\n", &_ram_start);
        printf("_heap_start=%p\n", &_heap_start);
        printf("_heap_end=%p\n", &_heap_end);
        printf("_ram_end=%p\n", &_ram_end);
    }

    // qstr info
    {
        mp_uint_t n_pool, n_qstr, n_str_data_bytes, n_total_bytes;
        qstr_pool_info(&n_pool, &n_qstr, &n_str_data_bytes, &n_total_bytes);
        printf("qstr:\n  n_pool=" UINT_FMT "\n  n_qstr=" UINT_FMT "\n  n_str_data_bytes=" UINT_FMT "\n  n_total_bytes=" UINT_FMT "\n", n_pool, n_qstr, n_str_data_bytes, n_total_bytes);
    }

    // GC info
    {
        gc_info_t info;
        gc_info(&info);
        printf("GC:\n");
        printf("  " UINT_FMT " total\n", info.total);
        printf("  " UINT_FMT " : " UINT_FMT "\n", info.used, info.free);
        printf("  1=" UINT_FMT " 2=" UINT_FMT " m=" UINT_FMT "\n", info.num_1block, info.num_2block, info.max_block);
    }

    // free space on flash
    {
        DWORD nclst;
        FATFS *fatfs;
        f_getfree("/flash", &nclst, &fatfs);
        printf("LFS free: %u bytes\n", (uint)(nclst * fatfs->csize * 512));
    }

    if (n_args == 1) {
        // arg given means dump gc allocation table
        gc_dump_alloc_table();
    }

    return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(machine_info_obj, 0, 1, machine_info);

// Returns a string of 12 bytes (96 bits), which is the unique ID for the MCU.
STATIC mp_obj_t machine_unique_id(void) {
    byte *id = (byte*)0x1fff7a10;
    return mp_obj_new_bytes(id, 12);
}
MP_DEFINE_CONST_FUN_OBJ_0(machine_unique_id_obj, machine_unique_id);

// Resets the pyboard in a manner similar to pushing the external RESET button.
STATIC mp_obj_t machine_reset(void) {
    NVIC_SystemReset();
    return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_0(machine_reset_obj, machine_reset);

// Activate the bootloader without BOOT* pins.
STATIC NORETURN mp_obj_t machine_bootloader(void) {
    pyb_usb_dev_deinit();
    storage_flush();

    HAL_RCC_DeInit();
    HAL_DeInit();

#if defined(MCU_SERIES_F7)
    // arm-none-eabi-gcc 4.9.0 does not correctly inline this
    // MSP function, so we write it out explicitly here.
    //__set_MSP(*((uint32_t*) 0x1FF00000));
    __ASM volatile ("movw r3, #0x0000\nmovt r3, #0x1FF0\nldr r3, [r3, #0]\nMSR msp, r3\n" : : : "r3", "sp");

    ((void (*)(void)) *((uint32_t*) 0x1FF00004))();
#else
    __HAL_REMAPMEMORY_SYSTEMFLASH();

    // arm-none-eabi-gcc 4.9.0 does not correctly inline this
    // MSP function, so we write it out explicitly here.
    //__set_MSP(*((uint32_t*) 0x00000000));
    __ASM volatile ("movs r3, #0\nldr r3, [r3, #0]\nMSR msp, r3\n" : : : "r3", "sp");

    ((void (*)(void)) *((uint32_t*) 0x00000004))();
#endif

    while (1);
}
MP_DEFINE_CONST_FUN_OBJ_0(machine_bootloader_obj, machine_bootloader);

// get or set the MCU frequencies
STATIC mp_uint_t machine_freq_calc_ahb_div(mp_uint_t wanted_div) {
    if (wanted_div <= 1) { return RCC_SYSCLK_DIV1; }
    else if (wanted_div <= 2) { return RCC_SYSCLK_DIV2; }
    else if (wanted_div <= 4) { return RCC_SYSCLK_DIV4; }
    else if (wanted_div <= 8) { return RCC_SYSCLK_DIV8; }
    else if (wanted_div <= 16) { return RCC_SYSCLK_DIV16; }
    else if (wanted_div <= 64) { return RCC_SYSCLK_DIV64; }
    else if (wanted_div <= 128) { return RCC_SYSCLK_DIV128; }
    else if (wanted_div <= 256) { return RCC_SYSCLK_DIV256; }
    else { return RCC_SYSCLK_DIV512; }
}
STATIC mp_uint_t machine_freq_calc_apb_div(mp_uint_t wanted_div) {
    if (wanted_div <= 1) { return RCC_HCLK_DIV1; }
    else if (wanted_div <= 2) { return RCC_HCLK_DIV2; }
    else if (wanted_div <= 4) { return RCC_HCLK_DIV4; }
    else if (wanted_div <= 8) { return RCC_HCLK_DIV8; }
    else { return RCC_SYSCLK_DIV16; }
}
STATIC mp_obj_t machine_freq(mp_uint_t n_args, const mp_obj_t *args) {
    if (n_args == 0) {
        // get
        mp_obj_t tuple[4] = {
           mp_obj_new_int(HAL_RCC_GetSysClockFreq()),
           mp_obj_new_int(HAL_RCC_GetHCLKFreq()),
           mp_obj_new_int(HAL_RCC_GetPCLK1Freq()),
           mp_obj_new_int(HAL_RCC_GetPCLK2Freq()),
        };
        return mp_obj_new_tuple(4, tuple);
    } else {
        // set
        mp_int_t wanted_sysclk = mp_obj_get_int(args[0]) / 1000000;

        // default PLL parameters that give 48MHz on PLL48CK
        uint32_t m = HSE_VALUE / 1000000, n = 336, p = 2, q = 7;
        uint32_t sysclk_source;

        // the following logic assumes HSE < HSI
        if (HSE_VALUE / 1000000 <= wanted_sysclk && wanted_sysclk < HSI_VALUE / 1000000) {
            // use HSE as SYSCLK
            sysclk_source = RCC_SYSCLKSOURCE_HSE;
        } else if (HSI_VALUE / 1000000 <= wanted_sysclk && wanted_sysclk < 24) {
            // use HSI as SYSCLK
            sysclk_source = RCC_SYSCLKSOURCE_HSI;
        } else {
            // search for a valid PLL configuration that keeps USB at 48MHz
            for (; wanted_sysclk > 0; wanted_sysclk--) {
                for (p = 2; p <= 8; p += 2) {
                    // compute VCO_OUT
                    mp_uint_t vco_out = wanted_sysclk * p;
                    // make sure VCO_OUT is between 192MHz and 432MHz
                    if (vco_out < 192 || vco_out > 432) {
                        continue;
                    }
                    // make sure Q is an integer
                    if (vco_out % 48 != 0) {
                        continue;
                    }
                    // solve for Q to get PLL48CK at 48MHz
                    q = vco_out / 48;
                    // make sure Q is in range
                    if (q < 2 || q > 15) {
                        continue;
                    }
                    // make sure N/M is an integer
                    if (vco_out % (HSE_VALUE / 1000000) != 0) {
                        continue;
                    }
                    // solve for N/M
                    mp_uint_t n_by_m = vco_out / (HSE_VALUE / 1000000);
                    // solve for M, making sure VCO_IN (=HSE/M) is between 1MHz and 2MHz
                    m = 192 / n_by_m;
                    while (m < (HSE_VALUE / 2000000) || n_by_m * m < 192) {
                        m += 1;
                    }
                    if (m > (HSE_VALUE / 1000000)) {
                        continue;
                    }
                    // solve for N
                    n = n_by_m * m;
                    // make sure N is in range
                    if (n < 192 || n > 432) {
                        continue;
                    }

                    // found values!
                    sysclk_source = RCC_SYSCLKSOURCE_PLLCLK;
                    goto set_clk;
                }
            }
            nlr_raise(mp_obj_new_exception_msg(&mp_type_ValueError, "can't make valid freq"));
        }

    set_clk:
        //printf("%lu %lu %lu %lu %lu\n", sysclk_source, m, n, p, q);

        // let the USB CDC have a chance to process before we change the clock
        HAL_Delay(USBD_CDC_POLLING_INTERVAL + 2);

        // desired system clock source is in sysclk_source
        RCC_ClkInitTypeDef RCC_ClkInitStruct;
        RCC_ClkInitStruct.ClockType = (RCC_CLOCKTYPE_SYSCLK | RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2);
        if (sysclk_source == RCC_SYSCLKSOURCE_PLLCLK) {
            // set HSE as system clock source to allow modification of the PLL configuration
            // we then change to PLL after re-configuring PLL
            RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSE;
        } else {
            // directly set the system clock source as desired
            RCC_ClkInitStruct.SYSCLKSource = sysclk_source;
        }
        wanted_sysclk *= 1000000;
        if (n_args >= 2) {
            // note: AHB freq required to be >= 14.2MHz for USB operation
            RCC_ClkInitStruct.AHBCLKDivider = machine_freq_calc_ahb_div(wanted_sysclk / mp_obj_get_int(args[1]));
        } else {
            RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
        }
        if (n_args >= 3) {
            RCC_ClkInitStruct.APB1CLKDivider = machine_freq_calc_apb_div(wanted_sysclk / mp_obj_get_int(args[2]));
        } else {
            RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV4;
        }
        if (n_args >= 4) {
            RCC_ClkInitStruct.APB2CLKDivider = machine_freq_calc_apb_div(wanted_sysclk / mp_obj_get_int(args[3]));
        } else {
            RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV2;
        }
        if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_1) != HAL_OK) {
            goto fail;
        }

        // re-configure PLL
        // even if we don't use the PLL for the system clock, we still need it for USB, RNG and SDIO
        RCC_OscInitTypeDef RCC_OscInitStruct;
        RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
        RCC_OscInitStruct.HSEState = RCC_HSE_ON;
        RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
        RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
        RCC_OscInitStruct.PLL.PLLM = m;
        RCC_OscInitStruct.PLL.PLLN = n;
        RCC_OscInitStruct.PLL.PLLP = p;
        RCC_OscInitStruct.PLL.PLLQ = q;
        if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK) {
            goto fail;
        }

        // set PLL as system clock source if wanted
        if (sysclk_source == RCC_SYSCLKSOURCE_PLLCLK) {
            RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_SYSCLK;
            RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
            if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_5) != HAL_OK) {
                goto fail;
            }
        }

        // re-init TIM3 for USB CDC rate
        timer_tim3_init();

        return mp_const_none;

    fail:;
        void NORETURN __fatal_error(const char *msg);
        __fatal_error("can't change freq");
    }
}
MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(machine_freq_obj, 0, 4, machine_freq);

STATIC mp_obj_t machine_sleep(void) {
    // takes longer to wake but reduces stop current
    HAL_PWREx_EnableFlashPowerDown();

    HAL_PWR_EnterSTOPMode(PWR_LOWPOWERREGULATOR_ON, PWR_STOPENTRY_WFI);

    // reconfigure the system clock after waking up

    // enable HSE
    __HAL_RCC_HSE_CONFIG(RCC_HSE_ON);
    while (!__HAL_RCC_GET_FLAG(RCC_FLAG_HSERDY)) {
    }

    // enable PLL
    __HAL_RCC_PLL_ENABLE();
    while (!__HAL_RCC_GET_FLAG(RCC_FLAG_PLLRDY)) {
    }

    // select PLL as system clock source
    MODIFY_REG(RCC->CFGR, RCC_CFGR_SW, RCC_SYSCLKSOURCE_PLLCLK);
    while (__HAL_RCC_GET_SYSCLK_SOURCE() != RCC_CFGR_SWS_PLL) {
    }

    return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_0(machine_sleep_obj, machine_sleep);

STATIC mp_obj_t machine_deepsleep(void) {
#if defined(MCU_SERIES_F7)
    printf("machine.deepsleep not supported yet\n");
#else
    // We need to clear the PWR wake-up-flag before entering standby, since
    // the flag may have been set by a previous wake-up event.  Furthermore,
    // we need to disable the wake-up sources while clearing this flag, so
    // that if a source is active it does actually wake the device.
    // See section 5.3.7 of RM0090.

    // Note: we only support RTC ALRA, ALRB, WUT and TS.
    // TODO support TAMP and WKUP (PA0 external pin).
    uint32_t irq_bits = RTC_CR_ALRAIE | RTC_CR_ALRBIE | RTC_CR_WUTIE | RTC_CR_TSIE;

    // save RTC interrupts
    uint32_t save_irq_bits = RTC->CR & irq_bits;

    // disable RTC interrupts
    RTC->CR &= ~irq_bits;

    // clear RTC wake-up flags
    RTC->ISR &= ~(RTC_ISR_ALRAF | RTC_ISR_ALRBF | RTC_ISR_WUTF | RTC_ISR_TSF);

    // clear global wake-up flag
    PWR->CR |= PWR_CR_CWUF;

    // enable previously-enabled RTC interrupts
    RTC->CR |= save_irq_bits;

    // enter standby mode
    HAL_PWR_EnterSTANDBYMode();
    // we never return; MCU is reset on exit from standby
#endif
    return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_0(machine_deepsleep_obj, machine_deepsleep);

#if 0
STATIC mp_obj_t machine_reset_cause(void) {
    return mp_obj_new_int(0);
    //return mp_obj_new_int(pyb_sleep_get_reset_cause());
}
STATIC MP_DEFINE_CONST_FUN_OBJ_0(machine_reset_cause_obj, machine_reset_cause);
#endif

STATIC const mp_map_elem_t machine_module_globals_table[] = {
    { MP_OBJ_NEW_QSTR(MP_QSTR___name__),            MP_OBJ_NEW_QSTR(MP_QSTR_machine) },
    { MP_OBJ_NEW_QSTR(MP_QSTR_info),                (mp_obj_t)&machine_info_obj },
    { MP_OBJ_NEW_QSTR(MP_QSTR_unique_id),           (mp_obj_t)&machine_unique_id_obj },
    { MP_OBJ_NEW_QSTR(MP_QSTR_reset),               (mp_obj_t)&machine_reset_obj },
    { MP_OBJ_NEW_QSTR(MP_QSTR_bootloader),          (mp_obj_t)&machine_bootloader_obj },
    { MP_OBJ_NEW_QSTR(MP_QSTR_freq),                (mp_obj_t)&machine_freq_obj },
#if MICROPY_HW_ENABLE_RNG
    { MP_OBJ_NEW_QSTR(MP_QSTR_rng),                 (mp_obj_t)&pyb_rng_get_obj },
#endif
    { MP_OBJ_NEW_QSTR(MP_QSTR_idle),                (mp_obj_t)&pyb_wfi_obj },
    { MP_OBJ_NEW_QSTR(MP_QSTR_sleep),               (mp_obj_t)&machine_sleep_obj },
    { MP_OBJ_NEW_QSTR(MP_QSTR_deepsleep),           (mp_obj_t)&machine_deepsleep_obj },
#if 0
    { MP_OBJ_NEW_QSTR(MP_QSTR_reset_cause),         (mp_obj_t)&machine_reset_cause_obj },
    { MP_OBJ_NEW_QSTR(MP_QSTR_wake_reason),         (mp_obj_t)&machine_wake_reason_obj },
#endif

    { MP_OBJ_NEW_QSTR(MP_QSTR_disable_irq),         (mp_obj_t)&pyb_disable_irq_obj },
    { MP_OBJ_NEW_QSTR(MP_QSTR_enable_irq),          (mp_obj_t)&pyb_enable_irq_obj },

    { MP_OBJ_NEW_QSTR(MP_QSTR_Pin),                 (mp_obj_t)&pin_type },

#if 0
    { MP_OBJ_NEW_QSTR(MP_QSTR_RTC),                 (mp_obj_t)&pyb_rtc_type },
    { MP_OBJ_NEW_QSTR(MP_QSTR_ADC),                 (mp_obj_t)&pyb_adc_type },
#endif
    // TODO: Per new API, both types below, if called with 1 arg (ID), should still
    // initialize master mode on the peripheral.
    { MP_OBJ_NEW_QSTR(MP_QSTR_I2C),                 (mp_obj_t)&pyb_i2c_type },
    { MP_OBJ_NEW_QSTR(MP_QSTR_SPI),                 (mp_obj_t)&pyb_spi_type },
#if 0
    { MP_OBJ_NEW_QSTR(MP_QSTR_UART),                (mp_obj_t)&pyb_uart_type },
    { MP_OBJ_NEW_QSTR(MP_QSTR_Timer),               (mp_obj_t)&pyb_timer_type },
    { MP_OBJ_NEW_QSTR(MP_QSTR_WDT),                 (mp_obj_t)&pyb_wdt_type },
    { MP_OBJ_NEW_QSTR(MP_QSTR_HeartBeat),           (mp_obj_t)&pyb_heartbeat_type },
    { MP_OBJ_NEW_QSTR(MP_QSTR_SD),                  (mp_obj_t)&pyb_sd_type },

    // class constants
    { MP_OBJ_NEW_QSTR(MP_QSTR_IDLE),                MP_OBJ_NEW_SMALL_INT(PYB_PWR_MODE_ACTIVE) },
    { MP_OBJ_NEW_QSTR(MP_QSTR_SLEEP),               MP_OBJ_NEW_SMALL_INT(PYB_PWR_MODE_LPDS) },
    { MP_OBJ_NEW_QSTR(MP_QSTR_DEEPSLEEP),           MP_OBJ_NEW_SMALL_INT(PYB_PWR_MODE_HIBERNATE) },
    { MP_OBJ_NEW_QSTR(MP_QSTR_POWER_ON),            MP_OBJ_NEW_SMALL_INT(PYB_SLP_PWRON_RESET) },
    { MP_OBJ_NEW_QSTR(MP_QSTR_HARD_RESET),          MP_OBJ_NEW_SMALL_INT(PYB_SLP_HARD_RESET) },
    { MP_OBJ_NEW_QSTR(MP_QSTR_WDT_RESET),           MP_OBJ_NEW_SMALL_INT(PYB_SLP_WDT_RESET) },
    { MP_OBJ_NEW_QSTR(MP_QSTR_DEEPSLEEP_RESET),     MP_OBJ_NEW_SMALL_INT(PYB_SLP_HIB_RESET) },
    { MP_OBJ_NEW_QSTR(MP_QSTR_SOFT_RESET),          MP_OBJ_NEW_SMALL_INT(PYB_SLP_SOFT_RESET) },
    { MP_OBJ_NEW_QSTR(MP_QSTR_WLAN_WAKE),           MP_OBJ_NEW_SMALL_INT(PYB_SLP_WAKED_BY_WLAN) },
    { MP_OBJ_NEW_QSTR(MP_QSTR_PIN_WAKE),            MP_OBJ_NEW_SMALL_INT(PYB_SLP_WAKED_BY_GPIO) },
    { MP_OBJ_NEW_QSTR(MP_QSTR_RTC_WAKE),            MP_OBJ_NEW_SMALL_INT(PYB_SLP_WAKED_BY_RTC) },
#endif
};

STATIC MP_DEFINE_CONST_DICT(machine_module_globals, machine_module_globals_table);

const mp_obj_module_t machine_module = {
    .base = { &mp_type_module },
    .name = MP_QSTR_machine,
    .globals = (mp_obj_dict_t*)&machine_module_globals,
};