#include <ch.h>
#include <chprintf.h>
#include <stdlib.h>
#include "parameters.h"
#include <stm32l1xx.h>
#include <string.h>
#include <fix16.h>

static int32_t * const data_eeprom = (int32_t * const)0x08080000;

parameters_t params =
{
#define X(type, name, default) default,
    PARAMETERS    
#undef X
};

typedef enum {T_int, T_fix16_t} param_type_t;

typedef struct {
    param_type_t type;
    int32_t *variable;
    char name[32];
} parameter_def_t;

#define X(type, name, default) {T_ ## type, (int32_t*)&params.name, #name},
static const parameter_def_t param_defs[] =
{
    PARAMETERS
};
#undef X
#define NUM_PARAMETERS (sizeof(param_defs) / sizeof(param_defs[0]))
static const int signature = 0x53504800 ^ PARAMETERS_VERSION;

void parameters_save()
{
    FLASH->PEKEYR = 0x89ABCDEF;
    FLASH->PEKEYR = 0x02030405;
    int32_t *dest = data_eeprom;
    
    *dest++ = signature;
    *dest++ = NUM_PARAMETERS;
    
    for (int i = 0; i < NUM_PARAMETERS; i++)
    {
        while (FLASH->SR & FLASH_SR_BSY) 
            chThdSleepMilliseconds(1);
        
        *dest++ = *(int32_t*)param_defs[i].variable;
    }
    FLASH->PECR |= FLASH_PECR_PELOCK;
}

bool parameters_load()
{
    int32_t *array = data_eeprom;
    if (*array++ != signature)
        return false;
    
    int count = *array++;
    if (count > NUM_PARAMETERS) count = NUM_PARAMETERS;
    
    for (int i = 0; i < count; i++)
    {
        *param_defs[i].variable = *array++;
    }
    
    return true;
}

static void format(param_type_t type, int32_t value, char buf[13])
{
    if (type == T_int)
        snprintf(buf, 13, "%ld", value);
    else
        fix16_to_str(value, buf, 4);
}

static int32_t parse(param_type_t type, const char *buf)
{
    if (type == T_int)
        return atoi(buf);
    else
        return fix16_from_str(buf);
}

void parameters_print(BaseChannel *chp, bool machine_readable)
{
    int32_t *array = data_eeprom;
    if (*array++ != signature)
    {
        chprintf(chp, "EEPROM signature invalid\r\n");
    }

    array++;
    
    for (int i = 0; i < NUM_PARAMETERS; i++)
    {
        char current[13];
        format(param_defs[i].type, *param_defs[i].variable, current);
        
        char stored[13];
        format(param_defs[i].type, *array++, stored);
        
        if (machine_readable)
            chprintf(chp, "set %s %s\r\n",param_defs[i].name, current);
        else
            chprintf(chp, "%32s current: %8s  stored: %8s\r\n",
                 param_defs[i].name, current, stored);
    }
}

bool parameter_set(const char *name, const char *value)
{
    for (int i = 0; i < NUM_PARAMETERS; i++)
    {
        if (strcasecmp(name, param_defs[i].name) == 0)
        {
            *param_defs[i].variable = parse(param_defs[i].type, value);
            return true;
        }
    }
    return false;
}

bool parameter_get(const char *name, char value[13])
{
    for (int i = 0; i < NUM_PARAMETERS; i++)
    {
        if (strcasecmp(name, param_defs[i].name) == 0)
        {
            format(param_defs[i].type, *param_defs[i].variable, value);
            return true;
        }
    }
    return false;
}