/**
 * Debug module
 */

#include "debug_config.h"
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <ctype.h>
#include <stdarg.h>
#include <stdio.h>
#include <time.h>
#include <strings.h>

#include <arpa/inet.h>
#include <netinet/in.h>
#include <stdio.h>
#include <string.h>

void log_dump(const char* prefix, const uint8_t* data, size_t len) {
    // Build packet data as hex string for single-line output
    char hex_buf[513]; // 256 bytes * 2 chars + 1 for null terminator
    size_t hex_len = 0;
    size_t show_len = (len > 128) ? 128 : len; // Show max 128 bytes
    
    for (size_t i = 0; i < show_len && hex_len < 512 - 3; i++) {
        hex_len += snprintf(hex_buf + hex_len, sizeof(hex_buf) - hex_len, "%02x", data[i]);
        if (i < show_len - 1 && (i + 1) % 32 == 0) { // Add space every 32 bytes
            hex_len += snprintf(hex_buf + hex_len, sizeof(hex_buf) - hex_len, " ");
        }
    }
    
    if (len > 128) {
        hex_len += snprintf(hex_buf + hex_len, sizeof(hex_buf) - hex_len, "...");
    }
    
    // Single-line debug output with packet info
    DEBUG_INFO(DEBUG_CATEGORY_ETCP, "%s: len=%zu hex=%s", prefix, len, hex_buf);
    
    // Additional debug info for first few bytes
//    if (len >= 2) {
//        DEBUG_DEBUG(DEBUG_CATEGORY_ETCP, "%s: first_bytes=%02x%02x last_bytes=%02x%02x", 
//                   prefix, data[0], data[1], data[len-2], data[len-1]);
//    }
}


size_t addr_to_string(const struct sockaddr_storage *addr, char *buf, size_t buflen) {
    if (!buf || buflen == 0)
        return 0;

    buf[0] = '\0';                 // всегда валидная строка

    char ip[INET6_ADDRSTRLEN];
    uint16_t port;
    int n;

    if (addr->ss_family == AF_INET) {
        const struct sockaddr_in *a = (const struct sockaddr_in *)addr;
        inet_ntop(AF_INET, &a->sin_addr, ip, sizeof(ip));
        port = ntohs(a->sin_port);

        n = snprintf(buf, buflen, "%s:%u", ip, port);

    } else if (addr->ss_family == AF_INET6) {
        const struct sockaddr_in6 *a = (const struct sockaddr_in6 *)addr;
        inet_ntop(AF_INET6, &a->sin6_addr, ip, sizeof(ip));
        port = ntohs(a->sin6_port);

        n = snprintf(buf, buflen, "[%s]:%u", ip, port);

    } else {
        return 0;
    }

    // snprintf гарантирует '\0', но на всякий случай:
    buf[buflen - 1] = '\0';

    // Возвращаем фактическую длину (как snprintf)
    return (n < 0) ? 0 : (size_t)n;
}


/* Get category by name */
static debug_category_t get_category_by_name(const char* name) {
    struct {
        const char* n;
        debug_category_t c;
    } map[] = {
        {"none", DEBUG_CATEGORY_NONE},
        {"uasync", DEBUG_CATEGORY_UASYNC},
        {"ll_queue", DEBUG_CATEGORY_LL_QUEUE},
        {"connection", DEBUG_CATEGORY_CONNECTION},
        {"etcp", DEBUG_CATEGORY_ETCP},
        {"crypto", DEBUG_CATEGORY_CRYPTO},
        {"memory", DEBUG_CATEGORY_MEMORY},
        {"timing", DEBUG_CATEGORY_TIMING},
        {"config", DEBUG_CATEGORY_CONFIG},
        {"tun", DEBUG_CATEGORY_TUN},
        {"routing", DEBUG_CATEGORY_ROUTING},
        {"timers", DEBUG_CATEGORY_TIMERS},
        {"all", DEBUG_CATEGORY_ALL},
        {NULL, 0}
    };

    for (int i = 0; map[i].n; i++) {
        if (strcasecmp(map[i].n, name) == 0) {
            return map[i].c;
        }
    }
    return DEBUG_CATEGORY_NONE;
}

/* Global debug configuration */
debug_config_t g_debug_config;
FILE* debug_output_file = NULL;

/* Initialize debug system with default settings */
void debug_config_init(void) {
    g_debug_config.level = DEBUG_LEVEL_ERROR;
    g_debug_config.categories = DEBUG_CATEGORY_ALL;
    g_debug_config.timestamp_enabled = 1;
    g_debug_config.function_name_enabled = 1;
    g_debug_config.file_line_enabled = 1;
    g_debug_config.output_file = NULL;
    
    if (debug_output_file && debug_output_file != stdout && debug_output_file != stderr) {
        fclose(debug_output_file);
    }
    debug_output_file = stdout;
}

/* Set debug level */
void debug_set_level(debug_level_t level) {
    g_debug_config.level = level;
}

/* Enable/disable specific categories */
void debug_enable_category(debug_category_t category) {
    g_debug_config.categories |= category;
}

void debug_disable_category(debug_category_t category) {
    g_debug_config.categories &= ~category;
}

void debug_set_categories(debug_category_t categories) {
    g_debug_config.categories = categories;
}

/* Set masks directly */
void debug_set_masks(debug_category_t categories, debug_level_t level) {
    g_debug_config.categories = categories;
    g_debug_config.level = level;
}

void debug_enable_function_name(int enable) {
    g_debug_config.function_name_enabled = enable;
}

void debug_enable_file_line(int enable) {
    g_debug_config.file_line_enabled = enable;
}

void debug_set_output_file(const char* file_path) {
    if (debug_output_file) return;// уже установлен, кто первый того и тапки
    FILE* new_file = fopen(file_path, "a");
    if (new_file) {
        debug_output_file = new_file;
        g_debug_config.output_file = file_path;
    }
}

/* Check if debug output should be shown for given level and category */
int debug_should_output(debug_level_t level, debug_category_t category) {

    /* Check if category is enabled */
    if (!(g_debug_config.categories & category)) {
        return 0;
    }
    
    /* Check if level is sufficient */
    if (level > g_debug_config.level) {
        return 0;
    }
    
    return 1;
}

/* Get current debug level */
debug_level_t debug_get_level(void) {
    return g_debug_config.level;
}

/* Get level name */
static const char* get_level_name(debug_level_t level) {
    switch (level) {
        case DEBUG_LEVEL_ERROR: return "ERROR";
        case DEBUG_LEVEL_WARN:  return "WARN";
        case DEBUG_LEVEL_INFO:  return "INFO";
        case DEBUG_LEVEL_DEBUG: return "DEBUG";
        case DEBUG_LEVEL_TRACE: return "TRACE";
        default: return "UNKNOWN";
    }
}

/* Format and output debug message */
void debug_output(debug_level_t level, debug_category_t category, 
                 const char* function, const char* file, int line,
                 const char* format, ...) {
    
#define BUFFER_SIZE 4096
    char buffer[BUFFER_SIZE];
    int offset = 0;
    size_t remaining = BUFFER_SIZE;
    
    va_list args;
    va_start(args, format);
    
    FILE* output = debug_output_file ? debug_output_file : stdout;

    /* Add timestamp if enabled */
    time_t now = time(NULL);
    struct tm* tm_info = localtime(&now);
    char time_str[32];
    strftime(time_str, sizeof(time_str), "%Y-%m-%d %H:%M:%S", tm_info);
    offset += snprintf(buffer + offset, remaining, "[%s] ", time_str);
    remaining = BUFFER_SIZE - offset;
    
    /* Add level */
    const char* level_name = get_level_name(level);
    offset += snprintf(buffer + offset, remaining, "[%s] ", level_name);
    remaining = BUFFER_SIZE - offset;
    
    /* Add category */
    offset += snprintf(buffer + offset, remaining, "[%llu] ", (unsigned long long)category);
    remaining = BUFFER_SIZE - offset;
    
    /* Add function name if enabled */
    if (g_debug_config.function_name_enabled && function) {
        offset += snprintf(buffer + offset, remaining, "%s() ", function);
        remaining = BUFFER_SIZE - offset;
    }
    
    /* Add file:line if enabled */
    if (g_debug_config.file_line_enabled && file) {
        offset += snprintf(buffer + offset, remaining, "(%s:%d) ", file, line);
        remaining = BUFFER_SIZE - offset;
    }
    
    /* Add the actual message */
    offset += vsnprintf(buffer + offset, remaining, format, args);
    remaining = BUFFER_SIZE - offset;
    
    /* Add newline */
    if (remaining > 1) {
        buffer[offset] = '\n';
        buffer[offset + 1] = '\0';
    } else {
        buffer[BUFFER_SIZE - 2] = '\n';
        buffer[BUFFER_SIZE - 1] = '\0';
    }
    
    va_end(args);
    
    /* Output the entire line at once */
    fprintf(output, "%s", buffer);
    fflush(output);
#undef BUFFER_SIZE
}

/* Parse debug configuration from string */
int debug_parse_config(const char* config_string) {
    if (!config_string || !*config_string) {
        return 0;
    }

    char* str = strdup(config_string);
    if (!str) {
        return -1;
    }

    debug_category_t categories = 0;
    debug_level_t level = DEBUG_LEVEL_NONE;

    char* token = strtok(str, ";");
    while (token) {
        /* Trim leading spaces */
        while (isspace(*token)) {
            token++;
        }

        char* eq = strchr(token, '=');
        if (!eq) {
            free(str);
            return -1;
        }

        *eq = '\0';
        char* key = token;
        char* value = eq + 1;

        /* Trim leading spaces in value */
        while (isspace(*value)) {
            value++;
        }

        if (strcasecmp(key, "modules") == 0) {
            char* mod_token = strtok(value, ",");
            while (mod_token) {
                /* Trim leading spaces */
                while (isspace(*mod_token)) {
                    mod_token++;
                }

                debug_category_t cat = get_category_by_name(mod_token);
                if (cat == DEBUG_CATEGORY_NONE) {
                    free(str);
                    return -1;
                }
                categories |= cat;
                mod_token = strtok(NULL, ",");
            }
        } else if (strcasecmp(key, "level") == 0) {
            int lev_num = atoi(value);
            if (lev_num < DEBUG_LEVEL_NONE || lev_num > DEBUG_LEVEL_TRACE) {
                free(str);
                return -1;
            }
            level = (debug_level_t)lev_num;
        } else {
            free(str);
            return -1;
        }

        token = strtok(NULL, ";");
    }

    debug_set_masks(categories, level);

    free(str);
    return 0;
}