// file    : core/logger.c
// project : Salis-VM
// author  : Paul Oliver <contact@pauloliver.dev>

// index:
// [section] includes
// [section] macros
// [section] extern globals
// [section] definitions

// ----------------------------------------------------------------------------
// [section] includes
// ----------------------------------------------------------------------------
#include <assert.h>
#include <stdarg.h>
#include <stdio.h>
#include <time.h>
#include <unistd.h>

#include "logger.h"

// ----------------------------------------------------------------------------
// [section] macros
// ----------------------------------------------------------------------------
#define COLOR_CLEAR "\033[0m"
#define COLOR_TRACE "\033[1;34m"
#define COLOR_INFO "\033[1;32m"
#define COLOR_ATTENTION "\033[1;33m"

#define LEVEL_TRACE "TRACE"
#define LEVEL_INFO "INFO"
#define LEVEL_ATTENTION "ATTENTION"

// ----------------------------------------------------------------------------
// [section] extern globals
// ----------------------------------------------------------------------------
void (*log_trace)(const char *format, ...) = log_trace_to_stdout;
void (*log_info)(const char *format, ...) = log_info_to_stdout;
void (*log_attention)(const char *format, ...) = log_attention_to_stdout;

// ----------------------------------------------------------------------------
// [section] definitions
// ----------------------------------------------------------------------------
static void log_to_buffer(char buffer[LOG_BUFFER_SIZE], const char *color_code, const char *level, const char *format, va_list args) {
    assert(level);
    assert(format);

    struct timespec ts;
    clock_gettime(CLOCK_REALTIME, &ts);
    int msec = (int)(ts.tv_nsec / 1000000l);
    struct tm tm = *localtime(&ts.tv_sec);
    pid_t pid = getpid();

    int rem = snprintf(
        buffer,
        LOG_BUFFER_SIZE,
        "\r%s%d-%02d-%02d %02d:%02d:%02d.%03d %07d [%s]%s ",
        color_code ? color_code : "",
        tm.tm_year + 1900,
        tm.tm_mon + 1,
        tm.tm_mday,
        tm.tm_hour,
        tm.tm_min,
        tm.tm_sec,
        msec,
        pid,
        level,
        color_code ? COLOR_CLEAR : ""
    );

    vsnprintf(buffer + rem, LOG_BUFFER_SIZE - rem, format, args);
}

void log_trace_to_stdout(const char *format, ...) {
    assert(format);
    (void)format;

#if defined(LOG_TRACE)
    va_list args;
    va_start(args, format);
    char buffer[LOG_BUFFER_SIZE];
    log_to_buffer(buffer, COLOR_TRACE, LEVEL_TRACE, format, args);
    printf("%s\n", buffer);
    fflush(stdout);
    va_end(args);
#endif
}

void log_info_to_stdout(const char *format, ...) {
    assert(format);
    va_list args;
    va_start(args, format);
    char buffer[LOG_BUFFER_SIZE];
    log_to_buffer(buffer, COLOR_INFO, LEVEL_INFO, format, args);
    printf("%s\n", buffer);
    fflush(stdout);
    va_end(args);
}

void log_attention_to_stdout(const char *format, ...) {
    assert(format);
    va_list args;
    va_start(args, format);
    char buffer[LOG_BUFFER_SIZE];
    log_to_buffer(buffer, COLOR_ATTENTION, LEVEL_ATTENTION, format, args);
    printf("%s\n", buffer);
    fflush(stdout);
    va_end(args);
}

void log_trace_to_buffer(char buffer[LOG_BUFFER_SIZE], const char *format, ...) {
    assert(format);
    (void)format;

#if defined(LOG_TRACE)
    va_list args;
    va_start(args, format);
    log_to_buffer(buffer, NULL, LEVEL_TRACE, format, args);
    va_end(args);
#endif
}

void log_info_to_buffer(char buffer[LOG_BUFFER_SIZE], const char *format, ...) {
    assert(format);
    va_list args;
    va_start(args, format);
    log_to_buffer(buffer, NULL, LEVEL_INFO, format, args);
    va_end(args);
}

void log_attention_to_buffer(char buffer[LOG_BUFFER_SIZE], const char *format, ...) {
    assert(format);
    va_list args;
    va_start(args, format);
    log_to_buffer(buffer, NULL, LEVEL_ATTENTION, format, args);
    va_end(args);
}