// SPDX-License-Identifier: GPL-3.0-or-later

#include "health.h"

// ----------------------------------------------------------------------------
// health alarm log load/save
// no need for locking - only one thread is reading / writing the alarms log

inline int health_alarm_log_open(RRDHOST *host) {
    if(host->health_log_fp)
        fclose(host->health_log_fp);

    host->health_log_fp = fopen(host->health_log_filename, "a");

    if(host->health_log_fp) {
        if (setvbuf(host->health_log_fp, NULL, _IOLBF, 0) != 0)
            error("HEALTH [%s]: cannot set line buffering on health log file '%s'.", rrdhost_hostname(host), host->health_log_filename);
        return 0;
    }

    error("HEALTH [%s]: cannot open health log file '%s'. Health data will be lost in case of netdata or server crash.", rrdhost_hostname(host), host->health_log_filename);
    return -1;
}

static inline void health_alarm_log_close(RRDHOST *host) {
    if(host->health_log_fp) {
        fclose(host->health_log_fp);
        host->health_log_fp = NULL;
    }
}

static inline void health_log_rotate(RRDHOST *host) {
    static size_t rotate_every = 0;

    if(unlikely(rotate_every == 0)) {
        rotate_every = (size_t)config_get_number(CONFIG_SECTION_HEALTH, "rotate log every lines", 2000);
        if(rotate_every < 100) rotate_every = 100;
    }

    if(unlikely(host->health_log_entries_written > rotate_every)) {
        if(unlikely(host->health_log_fp)) {
            health_alarm_log_close(host);

            char old_filename[FILENAME_MAX + 1];
            snprintfz(old_filename, FILENAME_MAX, "%s.old", host->health_log_filename);

            if(unlink(old_filename) == -1 && errno != ENOENT)
                error("HEALTH [%s]: cannot remove old alarms log file '%s'", rrdhost_hostname(host), old_filename);

            if(link(host->health_log_filename, old_filename) == -1 && errno != ENOENT)
                error("HEALTH [%s]: cannot move file '%s' to '%s'.", rrdhost_hostname(host), host->health_log_filename, old_filename);

            if(unlink(host->health_log_filename) == -1 && errno != ENOENT)
                error("HEALTH [%s]: cannot remove old alarms log file '%s'", rrdhost_hostname(host), host->health_log_filename);

            // open it with truncate
            host->health_log_fp = fopen(host->health_log_filename, "w");

            if(host->health_log_fp)
                fclose(host->health_log_fp);
            else
                error("HEALTH [%s]: cannot truncate health log '%s'", rrdhost_hostname(host), host->health_log_filename);

            host->health_log_fp = NULL;

            host->health_log_entries_written = 0;
            health_alarm_log_open(host);
        }
    }
}

inline void health_label_log_save(RRDHOST *host) {
    health_log_rotate(host);

    if(unlikely(host->health_log_fp)) {
        BUFFER *wb = buffer_create(1024);

        rrdlabels_to_buffer(localhost->rrdlabels, wb, "", "=", "", "\t ", NULL, NULL, NULL, NULL);
        char *write = (char *) buffer_tostring(wb);

        if (unlikely(fprintf(host->health_log_fp, "L\t%s", write) < 0))
            error("HEALTH [%s]: failed to save alarm log entry to '%s'. Health data may be lost in case of abnormal restart.",
                  rrdhost_hostname(host), host->health_log_filename);
        else
            host->health_log_entries_written++;

        buffer_free(wb);
    }
}

inline void health_alarm_log_save(RRDHOST *host, ALARM_ENTRY *ae) {
    health_log_rotate(host);
    if(unlikely(host->health_log_fp)) {
        if(unlikely(fprintf(host->health_log_fp
                            , "%c\t%s"
                        "\t%08x\t%08x\t%08x\t%08x\t%08x"
                        "\t%08x\t%08x\t%08x"
                        "\t%08x\t%08x\t%08x"
                        "\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s"
                        "\t%d\t%d\t%d\t%d"
                        "\t" NETDATA_DOUBLE_FORMAT_AUTO "\t" NETDATA_DOUBLE_FORMAT_AUTO
                        "\t%016"PRIx64""
                        "\t%s\t%s\t%s"
                        "\n"
                            , (ae->flags & HEALTH_ENTRY_FLAG_SAVED)?'U':'A'
                            , rrdhost_hostname(host)

                            , ae->unique_id
                            , ae->alarm_id
                            , ae->alarm_event_id
                            , ae->updated_by_id
                            , ae->updates_id

                            , (uint32_t)ae->when
                            , (uint32_t)ae->duration
                            , (uint32_t)ae->non_clear_duration
                            , (uint32_t)ae->flags
                            , (uint32_t)ae->exec_run_timestamp
                            , (uint32_t)ae->delay_up_to_timestamp

                            , ae_name(ae)
                            , ae_chart_name(ae)
                            , ae_family(ae)
                            , ae_exec(ae)
                            , ae_recipient(ae)
                            , ae_source(ae)
                            , ae_units(ae)
                            , ae_info(ae)

                            , ae->exec_code
                            , ae->new_status
                            , ae->old_status
                            , ae->delay

                            , ae->new_value
                            , ae->old_value
                            , (uint64_t)ae->last_repeat
                            , (ae->classification)?ae_classification(ae):"Unknown"
                            , (ae->component)?ae_component(ae):"Unknown"
                            , (ae->type)?ae_type(ae):"Unknown"
        ) < 0))
            error("HEALTH [%s]: failed to save alarm log entry to '%s'. Health data may be lost in case of abnormal restart.", rrdhost_hostname(host), host->health_log_filename);
        else {
            ae->flags |= HEALTH_ENTRY_FLAG_SAVED;
            host->health_log_entries_written++;
        }
    }else
        sql_health_alarm_log_save(host, ae);

#ifdef ENABLE_ACLK
    if (netdata_cloud_setting) {
        sql_queue_alarm_to_aclk(host, ae, 0);
    }
#endif
}

static uint32_t is_valid_alarm_id(RRDHOST *host, const char *chart, const char *name, uint32_t alarm_id)
{
    STRING *chart_string = string_strdupz(chart);
    STRING *name_string = string_strdupz(name);

    uint32_t ret = 1;

    ALARM_ENTRY *ae;
    for(ae = host->health_log.alarms; ae ;ae = ae->next) {
        if (unlikely(ae->alarm_id == alarm_id && (!(chart_string == ae->chart && name_string == ae->name)))) {
            ret = 0;
            break;
        }
    }

    string_freez(chart_string);
    string_freez(name_string);

    return ret;
}

static inline ssize_t health_alarm_log_read(RRDHOST *host, FILE *fp, const char *filename) {
    errno = 0;

    char *s, *buf = mallocz(65536 + 1);
    size_t line = 0, len = 0;
    ssize_t loaded = 0, updated = 0, errored = 0, duplicate = 0;

    DICTIONARY *all_rrdcalcs = dictionary_create(
        DICT_OPTION_NAME_LINK_DONT_CLONE | DICT_OPTION_VALUE_LINK_DONT_CLONE | DICT_OPTION_DONT_OVERWRITE_VALUE);
    RRDCALC *rc;
    foreach_rrdcalc_in_rrdhost_read(host, rc) {
        dictionary_set(all_rrdcalcs, rrdcalc_name(rc), rc, sizeof(*rc));
    }
    foreach_rrdcalc_in_rrdhost_done(rc);

    netdata_rwlock_rdlock(&host->health_log.alarm_log_rwlock);

    while((s = fgets_trim_len(buf, 65536, fp, &len))) {
        host->health_log_entries_written++;
        line++;

        int max_entries = 33, entries = 0;
        char *pointers[max_entries];

        pointers[entries++] = s++;
        while(*s) {
            if(unlikely(*s == '\t')) {
                *s = '\0';
                pointers[entries++] = ++s;
                if(entries >= max_entries) {
                    error("HEALTH [%s]: line %zu of file '%s' has more than %d entries. Ignoring excessive entries.", rrdhost_hostname(host), line, filename, max_entries);
                    break;
                }
            }
            else s++;
        }

        if(likely(*pointers[0] == 'L'))
            continue;

        if(likely(*pointers[0] == 'U' || *pointers[0] == 'A')) {
            ALARM_ENTRY *ae = NULL;

            if(entries < 27) {
                error("HEALTH [%s]: line %zu of file '%s' should have at least 27 entries, but it has %d. Ignoring it.", rrdhost_hostname(host), line, filename, entries);
                errored++;
                continue;
            }

            // check that we have valid ids
            uint32_t unique_id = (uint32_t)strtoul(pointers[2], NULL, 16);
            if(!unique_id) {
                error("HEALTH [%s]: line %zu of file '%s' states alarm entry with invalid unique id %u (%s). Ignoring it.", rrdhost_hostname(host), line, filename, unique_id, pointers[2]);
                errored++;
                continue;
            }

            uint32_t alarm_id = (uint32_t)strtoul(pointers[3], NULL, 16);
            if(!alarm_id) {
                error("HEALTH [%s]: line %zu of file '%s' states alarm entry for invalid alarm id %u (%s). Ignoring it.", rrdhost_hostname(host), line, filename, alarm_id, pointers[3]);
                errored++;
                continue;
            }

            // Check if we got last_repeat field
            time_t last_repeat = 0;
            if(entries > 27) {
                char* alarm_name = pointers[13];
                last_repeat = (time_t)strtoul(pointers[27], NULL, 16);

                rc = dictionary_get(all_rrdcalcs, alarm_name);
                if(unlikely(rc)) {
                    if (rrdcalc_isrepeating(rc)) {
                        rc->last_repeat = last_repeat;
                        // We iterate through repeating alarm entries only to
                        // find the latest last_repeat timestamp. Otherwise,
                        // there is no need to keep them in memory.
                        continue;
                    }
                }
            }

            if(unlikely(*pointers[0] == 'A')) {
                // make sure it is properly numbered
                if(unlikely(host->health_log.alarms && unique_id < host->health_log.alarms->unique_id)) {
                    error( "HEALTH [%s]: line %zu of file '%s' has alarm log entry %u in wrong order. Ignoring it."
                           , rrdhost_hostname(host), line, filename, unique_id);
                    errored++;
                    continue;
                }

                ae = callocz(1, sizeof(ALARM_ENTRY));
            }
            else if(unlikely(*pointers[0] == 'U')) {
                // find the original
                for(ae = host->health_log.alarms; ae ; ae = ae->next) {
                    if(unlikely(unique_id == ae->unique_id)) {
                        if(unlikely(*pointers[0] == 'A')) {
                            error("HEALTH [%s]: line %zu of file '%s' adds duplicate alarm log entry %u. Using the later."
                            , rrdhost_hostname(host), line, filename, unique_id);
                            *pointers[0] = 'U';
                            duplicate++;
                        }
                        break;
                    }
                    else if(unlikely(unique_id > ae->unique_id)) {
                        // no need to continue
                        // the linked list is sorted
                        ae = NULL;
                        break;
                    }
                }
            }

            // if not found, skip this line
            if(unlikely(!ae)) {
                // error("HEALTH [%s]: line %zu of file '%s' updates alarm log entry with unique id %u, but it is not found.", host->hostname, line, filename, unique_id);
                continue;
            }

            // check for a possible host mismatch
            //if(strcmp(pointers[1], host->hostname))
            //    error("HEALTH [%s]: line %zu of file '%s' provides an alarm for host '%s' but this is named '%s'.", host->hostname, line, filename, pointers[1], host->hostname);

            ae->unique_id               = unique_id;
            if (!is_valid_alarm_id(host, pointers[14], pointers[13], alarm_id)) {
                STRING *chart = string_strdupz(pointers[14]);
                STRING *name = string_strdupz(pointers[13]);
                alarm_id = rrdcalc_get_unique_id(host, chart, name, NULL);
                string_freez(chart);
                string_freez(name);
            }
            ae->alarm_id                = alarm_id;
            ae->alarm_event_id          = (uint32_t)strtoul(pointers[4], NULL, 16);
            ae->updated_by_id           = (uint32_t)strtoul(pointers[5], NULL, 16);
            ae->updates_id              = (uint32_t)strtoul(pointers[6], NULL, 16);

            ae->when                    = (uint32_t)strtoul(pointers[7], NULL, 16);
            ae->duration                = (uint32_t)strtoul(pointers[8], NULL, 16);
            ae->non_clear_duration      = (uint32_t)strtoul(pointers[9], NULL, 16);

            ae->flags                   = (uint32_t)strtoul(pointers[10], NULL, 16);
            ae->flags |= HEALTH_ENTRY_FLAG_SAVED;

            ae->exec_run_timestamp      = (uint32_t)strtoul(pointers[11], NULL, 16);
            ae->delay_up_to_timestamp   = (uint32_t)strtoul(pointers[12], NULL, 16);

            string_freez(ae->name);
            ae->name = string_strdupz(pointers[13]);

            string_freez(ae->chart);
            ae->chart = string_strdupz(pointers[14]);

            string_freez(ae->family);
            ae->family = string_strdupz(pointers[15]);

            string_freez(ae->exec);
            ae->exec = string_strdupz(pointers[16]);

            string_freez(ae->recipient);
            ae->recipient = string_strdupz(pointers[17]);

            string_freez(ae->source);
            ae->source = string_strdupz(pointers[18]);

            string_freez(ae->units);
            ae->units = string_strdupz(pointers[19]);

            string_freez(ae->info);
            ae->info = string_strdupz(pointers[20]);

            ae->exec_code   = str2i(pointers[21]);
            ae->new_status  = str2i(pointers[22]);
            ae->old_status  = str2i(pointers[23]);
            ae->delay       = str2i(pointers[24]);

            ae->new_value   = str2l(pointers[25]);
            ae->old_value   = str2l(pointers[26]);

            ae->last_repeat = last_repeat;

            if (likely(entries > 30)) {
                string_freez(ae->classification);
                ae->classification = string_strdupz(pointers[28]);

                string_freez(ae->component);
                ae->component = string_strdupz(pointers[29]);

                string_freez(ae->type);
                ae->type = string_strdupz(pointers[30]);
            }

            char value_string[100 + 1];
            string_freez(ae->old_value_string);
            string_freez(ae->new_value_string);
            ae->old_value_string = string_strdupz(format_value_and_unit(value_string, 100, ae->old_value, ae_units(ae), -1));
            ae->new_value_string = string_strdupz(format_value_and_unit(value_string, 100, ae->new_value, ae_units(ae), -1));

            // add it to host if not already there
            if(unlikely(*pointers[0] == 'A')) {
                ae->next = host->health_log.alarms;
                host->health_log.alarms = ae;
                sql_health_alarm_log_insert(host, ae);
                loaded++;
            }
            else {
                sql_health_alarm_log_update(host, ae);
                updated++;
            }

            if(unlikely(ae->unique_id > host->health_max_unique_id))
                host->health_max_unique_id = ae->unique_id;

            if(unlikely(ae->alarm_id >= host->health_max_alarm_id))
                host->health_max_alarm_id = ae->alarm_id;
        }
        else {
            error("HEALTH [%s]: line %zu of file '%s' is invalid (unrecognized entry type '%s').", rrdhost_hostname(host), line, filename, pointers[0]);
            errored++;
        }
    }

    netdata_rwlock_unlock(&host->health_log.alarm_log_rwlock);

    dictionary_destroy(all_rrdcalcs);
    all_rrdcalcs = NULL;

    freez(buf);

    if(!host->health_max_unique_id) host->health_max_unique_id = (uint32_t)now_realtime_sec();
    if(!host->health_max_alarm_id)  host->health_max_alarm_id  = (uint32_t)now_realtime_sec();

    host->health_log.next_log_id = host->health_max_unique_id + 1;
    if (unlikely(!host->health_log.next_alarm_id || host->health_log.next_alarm_id <= host->health_max_alarm_id))
        host->health_log.next_alarm_id = host->health_max_alarm_id + 1;

    debug(D_HEALTH, "HEALTH [%s]: loaded file '%s' with %zd new alarm entries, updated %zd alarms, errors %zd entries, duplicate %zd", rrdhost_hostname(host), filename, loaded, updated, errored, duplicate);
    return loaded;
}

inline void health_alarm_log_load(RRDHOST *host) {
    health_alarm_log_close(host);

    char filename[FILENAME_MAX + 1];
    snprintfz(filename, FILENAME_MAX, "%s.old", host->health_log_filename);
    FILE *fp = fopen(filename, "r");
    if(!fp)
        error("HEALTH [%s]: cannot open health file: %s", rrdhost_hostname(host), filename);
    else {
        health_alarm_log_read(host, fp, filename);
        fclose(fp);
    }

    host->health_log_entries_written = 0;
    fp = fopen(host->health_log_filename, "r");
    if(!fp)
        error("HEALTH [%s]: cannot open health file: %s", rrdhost_hostname(host), host->health_log_filename);
    else {
        health_alarm_log_read(host, fp, host->health_log_filename);
        fclose(fp);
    }
}


// ----------------------------------------------------------------------------
// health alarm log management

inline ALARM_ENTRY* health_create_alarm_entry(
    RRDHOST *host,
    uint32_t alarm_id,
    uint32_t alarm_event_id,
    const uuid_t config_hash_id,
    time_t when,
    STRING *name,
    STRING *chart,
    STRING *chart_context,
    STRING *family,
    STRING *class,
    STRING *component,
    STRING *type,
    STRING *exec,
    STRING *recipient,
    time_t duration,
    NETDATA_DOUBLE old_value,
    NETDATA_DOUBLE new_value,
    RRDCALC_STATUS old_status,
    RRDCALC_STATUS new_status,
    STRING *source,
    STRING *units,
    STRING *info,
    int delay,
    uint32_t flags
) {
    debug(D_HEALTH, "Health adding alarm log entry with id: %u", host->health_log.next_log_id);

    ALARM_ENTRY *ae = callocz(1, sizeof(ALARM_ENTRY));
    ae->name = string_dup(name);
    ae->chart = string_dup(chart);
    ae->chart_context = string_dup(chart_context);

    uuid_copy(ae->config_hash_id, *((uuid_t *) config_hash_id));

    ae->family = string_dup(family);
    ae->classification = string_dup(class);
    ae->component = string_dup(component);
    ae->type = string_dup(type);
    ae->exec = string_dup(exec);
    ae->recipient = string_dup(recipient);
    ae->source = string_dup(source);
    ae->units = string_dup(units);

    ae->unique_id = host->health_log.next_log_id++;
    ae->alarm_id = alarm_id;
    ae->alarm_event_id = alarm_event_id;
    ae->when = when;
    ae->old_value = old_value;
    ae->new_value = new_value;

    char value_string[100 + 1];
    ae->old_value_string = string_strdupz(format_value_and_unit(value_string, 100, ae->old_value, ae_units(ae), -1));
    ae->new_value_string = string_strdupz(format_value_and_unit(value_string, 100, ae->new_value, ae_units(ae), -1));

    ae->info = string_dup(info);
    ae->old_status = old_status;
    ae->new_status = new_status;
    ae->duration = duration;
    ae->delay = delay;
    ae->delay_up_to_timestamp = when + delay;
    ae->flags |= flags;

    ae->last_repeat = 0;

    if(ae->old_status == RRDCALC_STATUS_WARNING || ae->old_status == RRDCALC_STATUS_CRITICAL)
        ae->non_clear_duration += ae->duration;

    return ae;
}

inline void health_alarm_log_add_entry(
        RRDHOST *host,
        ALARM_ENTRY *ae
) {
    debug(D_HEALTH, "Health adding alarm log entry with id: %u", ae->unique_id);

    // link it
    netdata_rwlock_wrlock(&host->health_log.alarm_log_rwlock);
    ae->next = host->health_log.alarms;
    host->health_log.alarms = ae;
    host->health_log.count++;
    netdata_rwlock_unlock(&host->health_log.alarm_log_rwlock);

    // match previous alarms
    netdata_rwlock_rdlock(&host->health_log.alarm_log_rwlock);
    ALARM_ENTRY *t;
    for(t = host->health_log.alarms ; t ; t = t->next) {
        if(t != ae && t->alarm_id == ae->alarm_id) {
            if(!(t->flags & HEALTH_ENTRY_FLAG_UPDATED) && !t->updated_by_id) {
                t->flags |= HEALTH_ENTRY_FLAG_UPDATED;
                t->updated_by_id = ae->unique_id;
                ae->updates_id = t->unique_id;

                if((t->new_status == RRDCALC_STATUS_WARNING || t->new_status == RRDCALC_STATUS_CRITICAL) &&
                   (t->old_status == RRDCALC_STATUS_WARNING || t->old_status == RRDCALC_STATUS_CRITICAL))
                    ae->non_clear_duration += t->non_clear_duration;

                health_alarm_log_save(host, t);
            }

            // no need to continue
            break;
        }
    }
    netdata_rwlock_unlock(&host->health_log.alarm_log_rwlock);

    health_alarm_log_save(host, ae);
}

inline void health_alarm_log_free_one_nochecks_nounlink(ALARM_ENTRY *ae) {
    string_freez(ae->name);
    string_freez(ae->chart);
    string_freez(ae->chart_context);
    string_freez(ae->family);
    string_freez(ae->classification);
    string_freez(ae->component);
    string_freez(ae->type);
    string_freez(ae->exec);
    string_freez(ae->recipient);
    string_freez(ae->source);
    string_freez(ae->units);
    string_freez(ae->info);
    string_freez(ae->old_value_string);
    string_freez(ae->new_value_string);
    freez(ae);
}

inline void health_alarm_log_free(RRDHOST *host) {
    netdata_rwlock_wrlock(&host->health_log.alarm_log_rwlock);

    ALARM_ENTRY *ae;
    while((ae = host->health_log.alarms)) {
        host->health_log.alarms = ae->next;
        health_alarm_log_free_one_nochecks_nounlink(ae);
    }

    netdata_rwlock_unlock(&host->health_log.alarm_log_rwlock);
}