/*

 * Copyright (C) 2019 by Sukchan Lee <acetcom@gmail.com>

 *

 * This file is part of Open5GS.

 *

 * This program is free software: you can redistribute it and/or modify

 * it under the terms of the GNU Affero General Public License as published by

 * the Free Software Foundation, either version 3 of the License, or

 * (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program.  If not, see <https://www.gnu.org/licenses/>.

 */

#include "core-config-private.h"

#if HAVE_CTYPE_H

#include <ctype.h>

#endif

#if HAVE_STDARG_H

#include <stdarg.h>

#endif

#include "ogs-core.h"

#define TA_NOR              "\033[0m"       /* all off */

#define TA_FGC_BLACK        "\033[30m"      /* Black */

#define TA_FGC_RED          "\033[31m"      /* Red */

#define TA_FGC_BOLD_RED     "\033[1;31m"    /* Bold Red */

#define TA_FGC_GREEN        "\033[32m"      /* Green */

#define TA_FGC_BOLD_GREEN   "\033[1;32m"    /* Bold Green */

#define TA_FGC_YELLOW       "\033[33m"      /* Yellow */

#define TA_FGC_BOLD_YELLOW  "\033[1;33m"    /* Bold Yellow */

#define TA_FGC_BOLD_BLUE    "\033[1;34m"    /* Bold Blue */

#define TA_FGC_BOLD_MAGENTA "\033[1;35m"    /* Bold Magenta */

#define TA_FGC_BOLD_CYAN    "\033[1;36m"    /* Bold Cyan */

#define TA_FGC_WHITE        "\033[37m"      /* White  */

#define TA_FGC_BOLD_WHITE   "\033[1;37m"    /* Bold White  */

#define TA_FGC_DEFAULT      "\033[39m"      /* default */

typedef enum {

    OGS_LOG_STDERR_TYPE,

    OGS_LOG_FILE_TYPE,

} ogs_log_type_e;

typedef struct ogs_log_s {

    ogs_lnode_t node;

    ogs_log_type_e type;

    union {

        struct {

            FILE *out;

            const char *name;

        } file;

    };

    struct {

    ED7(uint8_t color:1;,

        uint8_t timestamp:1;,

        uint8_t domain:1;,

        uint8_t level:1;,

        uint8_t fileline:1;,

        uint8_t function:1;,

        uint8_t linefeed:1;)

    } print;

    void (*writer)(ogs_log_t *log, ogs_log_level_e level, const char *string);

} ogs_log_t;

typedef struct ogs_log_domain_s {

    ogs_lnode_t node;

    int id;

    ogs_log_level_e level;

    const char *name;

} ogs_log_domain_t;

const char *level_strings[] = {

    NULL,

    "FATAL", "ERROR", "WARNING", "INFO", "DEBUG", "TRACE",

};

static OGS_POOL(log_pool, ogs_log_t);

static OGS_LIST(log_list);

static OGS_POOL(domain_pool, ogs_log_domain_t);

static OGS_LIST(domain_list);

static ogs_log_t *add_log(ogs_log_type_e type);

static int file_cycle(ogs_log_t *log);

static char *log_timestamp(char *buf, char *last,

        int use_color);

static char *log_domain(char *buf, char *last,

        const char *name, int use_color);

static char *log_content(char *buf, char *last,

        const char *format, va_list ap);

static char *log_level(char *buf, char *last,

        ogs_log_level_e level, int use_color);

static char *log_linefeed(char *buf, char *last);

static void file_writer(

        ogs_log_t *log, ogs_log_level_e level, const char *string);

void ogs_log_init(void)

{

    ogs_pool_init(&log_pool, ogs_core()->log.pool);

    ogs_pool_init(&domain_pool, ogs_core()->log.domain_pool);

    ogs_log_add_domain("core", ogs_core()->log.level);

    ogs_log_add_stderr();

}

void ogs_log_final(void)

{

    ogs_log_t *log, *saved_log;

    ogs_log_domain_t *domain, *saved_domain;

    ogs_list_for_each_safe(&log_list, saved_log, log)

        ogs_log_remove(log);

    ogs_pool_final(&log_pool);

    ogs_list_for_each_safe(&domain_list, saved_domain, domain)

        ogs_log_remove_domain(domain);

    ogs_pool_final(&domain_pool);

}

void ogs_log_cycle(void)

{

    ogs_log_t *log = NULL;

    ogs_list_for_each(&log_list, log) {

        switch(log->type) {

        case OGS_LOG_FILE_TYPE:

            file_cycle(log);

        default:

            break;

        }

    }

}

ogs_log_t *ogs_log_add_stderr(void)

{

    ogs_log_t *log = NULL;

    log = add_log(OGS_LOG_STDERR_TYPE);

    ogs_assert(log);

    log->file.out = stderr;

    log->writer = file_writer;

#if !defined(_WIN32)

    log->print.color = 1;

#endif

    return log;

}

ogs_log_t *ogs_log_add_file(const char *name)

{

    FILE *out = NULL;

    ogs_log_t *log = NULL;

    out = fopen(name, "a");

    if (!out) 

        return NULL;

    log = add_log(OGS_LOG_FILE_TYPE);

    ogs_assert(log);

    log->file.name = name;

    log->file.out = out;

    log->writer = file_writer;

    return log;

}

void ogs_log_remove(ogs_log_t *log)

{

    ogs_assert(log);

    ogs_list_remove(&log_list, log);

    if (log->type == OGS_LOG_FILE_TYPE) {

        ogs_assert(log->file.out);

        fclose(log->file.out);

        log->file.out = NULL;

    }

    ogs_pool_free(&log_pool, log);

}

ogs_log_domain_t *ogs_log_add_domain(const char *name, ogs_log_level_e level)

{

    ogs_log_domain_t *domain = NULL;

    ogs_assert(name);

    ogs_pool_alloc(&domain_pool, &domain);

    ogs_assert(domain);

    domain->name = name;

    domain->id = ogs_pool_index(&domain_pool, domain);

    domain->level = level;

    ogs_list_add(&domain_list, domain);

    return domain;

}

ogs_log_domain_t *ogs_log_find_domain(const char *name)

{

    ogs_log_domain_t *domain = NULL;

    ogs_assert(name);

    ogs_list_for_each(&domain_list, domain)

        if (!ogs_strcasecmp(domain->name, name))

            return domain;

    return NULL;

}

void ogs_log_remove_domain(ogs_log_domain_t *domain)

{

    ogs_assert(domain);

    ogs_list_remove(&domain_list, domain);

    ogs_pool_free(&domain_pool, domain);

}

void ogs_log_set_domain_level(int id, ogs_log_level_e level)

{

    ogs_log_domain_t *domain = NULL;

    ogs_assert(id > 0 && id <= ogs_core()->log.domain_pool);

    domain = ogs_pool_find(&domain_pool, id);

    ogs_assert(domain);

    domain->level = level;

}

ogs_log_level_e ogs_log_get_domain_level(int id)

{

    ogs_log_domain_t *domain = NULL;

    ogs_assert(id > 0 && id <= ogs_core()->log.domain_pool);

    domain = ogs_pool_find(&domain_pool, id);

    ogs_assert(domain);

    return domain->level;

}

const char *ogs_log_get_domain_name(int id)

{

    ogs_log_domain_t *domain = NULL;

    ogs_assert(id > 0 && id <= ogs_core()->log.domain_pool);

    domain = ogs_pool_find(&domain_pool, id);

    ogs_assert(domain);

    return domain->name;

}

int ogs_log_get_domain_id(const char *name)

{

    ogs_log_domain_t *domain = NULL;

    ogs_assert(name);

    domain = ogs_log_find_domain(name);

    ogs_assert(domain);

    return domain->id;

}

void ogs_log_install_domain(int *domain_id,

        const char *name, ogs_log_level_e level)

{

    ogs_log_domain_t *domain = NULL;

    ogs_assert(domain_id);

    ogs_assert(name);

    domain = ogs_log_find_domain(name);

    if (domain) {

        ogs_warn("`%s` log-domain duplicated", name);

        if (level != domain->level) {

            ogs_warn("[%s]->[%s] log-level changed",

                    level_strings[domain->level], level_strings[level]);

            ogs_log_set_domain_level(domain->id, level);

        }

    } else {

        domain = ogs_log_add_domain(name, level);

        ogs_assert(domain);

    }

    *domain_id = domain->id;

}

void ogs_log_set_mask_level(const char *_mask, ogs_log_level_e level)

{

    ogs_log_domain_t *domain = NULL;

    if (_mask) {

        const char *delim = " \t\n,:";

        char *mask = NULL;

        char *saveptr;

        char *name;

        mask = ogs_strdup(_mask);

        ogs_assert(mask);

        for (name = ogs_strtok_r(mask, delim, &saveptr);

            name != NULL;

            name = ogs_strtok_r(NULL, delim, &saveptr)) {

            domain = ogs_log_find_domain(name);

            if (domain)

                domain->level = level;

        }

        ogs_free(mask);

    } else {

        ogs_list_for_each(&domain_list, domain)

            domain->level = level;

    }

}

void ogs_log_set_timestamp(ogs_log_ts_e ts_default, ogs_log_ts_e ts_file)

{

    ogs_log_t *log;

    if (ts_default == OGS_LOG_TS_UNSET)

        ts_default = OGS_LOG_TS_ENABLED;

    if (ts_file == OGS_LOG_TS_UNSET)

        ts_file = ts_default;

    ogs_list_for_each(&log_list, log) {

        switch (log->type) {

            case OGS_LOG_FILE_TYPE:

                log->print.timestamp = (ts_file == OGS_LOG_TS_ENABLED);

                break;

            default:

                log->print.timestamp = (ts_default == OGS_LOG_TS_ENABLED);

                break;

        }

    }

}

static ogs_log_level_e ogs_log_level_from_string(const char *string)

{

    ogs_log_level_e level = OGS_ERROR;

    if (!strcasecmp(string, "none")) level = OGS_LOG_NONE;

    else if (!strcasecmp(string, "fatal")) level = OGS_LOG_FATAL;

    else if (!strcasecmp(string, "error")) level = OGS_LOG_ERROR;

    else if (!strcasecmp(string, "warn")) level = OGS_LOG_WARN;

    else if (!strcasecmp(string, "info")) level = OGS_LOG_INFO;

    else if (!strcasecmp(string, "debug")) level = OGS_LOG_DEBUG;

    else if (!strcasecmp(string, "trace")) level = OGS_LOG_TRACE;

    return level;

}

int ogs_log_config_domain(const char *domain, const char *level)

{

    if (domain || level) {

        int l = ogs_core()->log.level;

        if (level) {

            l = ogs_log_level_from_string(level);

            if (l == OGS_ERROR) {

                ogs_error("Invalid LOG-LEVEL "

                        "[none:fatal|error|warn|info|debug|trace]: %s\n",

                        level);

                return OGS_ERROR;

            }

        }

        ogs_log_set_mask_level(domain, l);

    }

    return OGS_OK;

}

void ogs_log_vprintf(ogs_log_level_e level, int id,

    ogs_err_t err, const char *file, int line, const char *func,

    int content_only, const char *format, va_list ap)

{

    ogs_log_t *log = NULL;

    ogs_log_domain_t *domain = NULL;

    char logstr[OGS_HUGE_LEN];

    char *p, *last;

    int wrote_stderr = 0;

    ogs_list_for_each(&log_list, log) {

        domain = ogs_pool_find(&domain_pool, id);

        if (!domain) {

            fprintf(stderr, "No LogDomain[id:%d] in %s:%d", id, file, line);

            ogs_assert_if_reached();

        }

        if (domain->level < level)

            return;

        p = logstr;

        last = logstr + OGS_HUGE_LEN;

        if (!content_only) {

            if (log->print.timestamp)

                p = log_timestamp(p, last, log->print.color);

            if (log->print.domain)

                p = log_domain(p, last, domain->name, log->print.color);

            if (log->print.level)

                p = log_level(p, last, level, log->print.color);

        }

        p = log_content(p, last, format, ap);

        if (err) {

            char errbuf[OGS_HUGE_LEN];

            p = ogs_slprintf(p, last, " (%d:%s)",

                    (int)err, ogs_strerror(err, errbuf, OGS_HUGE_LEN));

        }

        if (!content_only) {

            if (log->print.fileline)

                p = ogs_slprintf(p, last, " (%s:%d)", file, line);

            if (log->print.function)

                p = ogs_slprintf(p, last, " %s()", func);

            if (log->print.linefeed) 

                p = log_linefeed(p, last);

        }

        log->writer(log, level, logstr);

        if (log->type == OGS_LOG_STDERR_TYPE)

            wrote_stderr = 1;

    }

    if (!wrote_stderr)

    {

        int use_color = 0;

#if !defined(_WIN32)

        use_color = 1;

#endif

        p = logstr;

        last = logstr + OGS_HUGE_LEN;

        if (!content_only) {

            p = log_timestamp(p, last, use_color);

            p = log_level(p, last, level, use_color);

        }

        p = log_content(p, last, format, ap);

        if (!content_only) {

            p = ogs_slprintf(p, last, " (%s:%d)", file, line);

            p = ogs_slprintf(p, last, " %s()", func);

            p = log_linefeed(p, last);

        }

        fprintf(stderr, "%s", logstr);

        fflush(stderr);

    }

}

void ogs_log_printf(ogs_log_level_e level, int id,

    ogs_err_t err, const char *file, int line, const char *func,

    int content_only, const char *format, ...)

{

    va_list args;

    va_start(args, format);

    ogs_log_vprintf(level, id,

            err, file, line, func, content_only, format, args);

    va_end(args);

}

void ogs_log_hexdump_func(ogs_log_level_e level, int id,

        const unsigned char *data, size_t len)

{

    size_t n, m;

    char dumpstr[OGS_HUGE_LEN];

    char *p, *last;

    /*

     * Nothing is written to dumpstr when len is zero, so printing it

     * would output an uninitialized stack buffer.

     */

    if (!len)

        return;

    last = dumpstr + OGS_HUGE_LEN;

    p = dumpstr;

    for (n = 0; n < len; n += 16) {

        p = ogs_slprintf(p, last, "%04x: ", (int)n);

        for (m = n; m < n + 16; m++) {

            if (m > n && (m % 4) == 0)

                p = ogs_slprintf(p, last, " ");

            if (m < len)

                p = ogs_slprintf(p, last, "%02x", data[m]);

            else

                p = ogs_slprintf(p, last, "  ");

        }

        p = ogs_slprintf(p, last, "   ");

        for (m = n; m < len && m < n + 16; m++)

            p = ogs_slprintf(p, last, "%c", isprint(data[m]) ? data[m] : '.');

        p = ogs_slprintf(p, last, "\n");

    }

    ogs_log_print(level, "%s", dumpstr);

}

static ogs_log_t *add_log(ogs_log_type_e type)

{

    ogs_log_t *log = NULL;

    ogs_pool_alloc(&log_pool, &log);

    ogs_assert(log);

    memset(log, 0, sizeof *log);

    log->type = type;

    log->print.timestamp = 1;

    log->print.domain = 1;

    log->print.level = 1;

    log->print.fileline = 1;

    log->print.linefeed = 1;

    ogs_list_add(&log_list, log);

    return log;

}

static int file_cycle(ogs_log_t *log)

{

    ogs_assert(log);

    ogs_assert(log->file.out);

    ogs_assert(log->file.name);

    fclose(log->file.out);

    log->file.out = fopen(log->file.name, "a");

    ogs_assert(log->file.out);

    return 0;

}

static char *log_timestamp(char *buf, char *last,

        int use_color)

{

    struct timeval tv;

    struct tm tm;

    char nowstr[32];

    ogs_gettimeofday(&tv);

    ogs_localtime(tv.tv_sec, &tm);

    strftime(nowstr, sizeof nowstr, "%m/%d %H:%M:%S", &tm);

    buf = ogs_slprintf(buf, last, "%s%s.%03d%s: ",

            use_color ? TA_FGC_GREEN : "",

            nowstr, (int)(tv.tv_usec/1000),

            use_color ? TA_NOR : "");

    return buf;

}

static char *log_domain(char *buf, char *last,

        const char *name, int use_color)

{

    buf = ogs_slprintf(buf, last, "[%s%s%s] ",

            use_color ? TA_FGC_YELLOW : "",

            name,

            use_color ? TA_NOR : "");

    return buf;

}

static char *log_level(char *buf, char *last,

        ogs_log_level_e level, int use_color)

{

    const char *colors[] = {

        TA_NOR,

        TA_FGC_BOLD_RED, TA_FGC_BOLD_YELLOW, TA_FGC_BOLD_CYAN,

        TA_FGC_BOLD_GREEN, TA_FGC_BOLD_WHITE, TA_FGC_WHITE,

    };

    buf = ogs_slprintf(buf, last, "%s%s%s: ",

            use_color ? colors[level] : "",

            level_strings[level],

            use_color ? TA_NOR : "");

    return buf;

}

static char *log_content(char *buf, char *last,

        const char *format, va_list ap)

{

    va_list bp;

    va_copy(bp, ap);

#pragma GCC diagnostic push

#pragma GCC diagnostic ignored "-Wformat-nonliteral"

    buf = ogs_vslprintf(buf, last, format, bp);

#pragma GCC diagnostic pop

    va_end(bp);

    return buf;

}

static char *log_linefeed(char *buf, char *last)

{

#if defined(_WIN32)

    if (buf > last - 3)

        buf = last - 3;

    buf = ogs_slprintf(buf, last, "\r\n");

#else

    if (buf > last - 2)

        buf = last - 2;

    buf = ogs_slprintf(buf, last, "\n");

#endif

    return buf;

}

static void file_writer(

        ogs_log_t *log, ogs_log_level_e level, const char *string)

{

    fprintf(log->file.out, "%s", string);

    fflush(log->file.out);

}