/*
 * (C) Copyright 2005- ECMWF.
 *
 * This software is licensed under the terms of the Apache Licence Version 2.0
 * which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
 *
 * In applying this licence, ECMWF does not waive the privileges and immunities granted to it by
 * virtue of its status as an intergovernmental organisation nor does it submit to any jurisdiction.
 */

#include "SmartTable.h"
#include "sync/Mutex.h"
#include <cctype>

eccodes::accessor::SmartTable _grib_accessor_smart_table;
eccodes::Accessor* grib_accessor_smart_table = &_grib_accessor_smart_table;

void grib_smart_table_delete(grib_context* c)
{
    grib_smart_table* t = c->smart_table;
    while (t) {
        grib_smart_table* s = t->next;
        int k;

        for (size_t i = 0; i < t->numberOfEntries; i++) {
            if (t->entries[i].abbreviation)
                grib_context_free_persistent(c, t->entries[i].abbreviation);
            for (k = 0; k < MAX_SMART_TABLE_COLUMNS; k++) {
                if (t->entries[i].column[k])
                    grib_context_free_persistent(c, t->entries[i].column[k]);
            }
        }
        grib_context_free_persistent(c, t->entries);
        grib_context_free_persistent(c, t->filename[0]);
        if (t->filename[1])
            grib_context_free_persistent(c, t->filename[1]);
        if (t->filename[2])
            grib_context_free_persistent(c, t->filename[2]);
        grib_context_free_persistent(c, t->recomposed_name[0]);
        if (t->recomposed_name[1])
            grib_context_free_persistent(c, t->recomposed_name[1]);
        if (t->recomposed_name[2])
            grib_context_free_persistent(c, t->recomposed_name[2]);
        grib_context_free_persistent(c, t);
        t = s;
    }
}

namespace eccodes::accessor
{

static eccodes::sync::Mutex mutex;

static int grib_load_smart_table(grib_context* c, const char* filename, const char* recomposed_name, size_t size, grib_smart_table* t);

void SmartTable::init(const long len, grib_arguments* params)
{
    int n = 0;
    grib_handle* hand = get_enclosing_handle();

    values_      = params->get_name(hand, n++);
    tablename_   = params->get_string(hand, n++);
    masterDir_   = params->get_name(hand, n++);
    localDir_    = params->get_name(hand, n++);
    widthOfCode_ = params->get_long(hand, n++);
    extraDir_    = params->get_name(hand, n++);
    extraTable_  = params->get_string(hand, n++);

    Unsigned::length_ = 0;
    flags_ |= GRIB_ACCESSOR_FLAG_READ_ONLY;
    dirty_          = 1;
    tableCodesSize_ = 0;
    tableCodes_     = 0;
    table_          = NULL;
}

grib_smart_table* SmartTable::load_table()
{
    size_t size            = 0;
    grib_handle* h         = this->parent_->h;
    grib_context* c        = h->context;
    grib_smart_table* t    = NULL;
    grib_smart_table* next = NULL;
    char* filename         = 0;

    char recomposed[1024]      = {0,};
    char localRecomposed[1024] = {0,};
    char* localFilename        = 0;
    char extraRecomposed[1024] = {0,};
    char* extraFilename        = 0;
    char masterDir[1024] = {0,};
    char localDir[1024]  = {0,};
    char extraDir[1024]  = {0,};
    size_t len = 1024;

    if (masterDir_ != NULL) {
        grib_get_string(h, masterDir_, masterDir, &len);
    }

    len = 1024;
    if (localDir_ != NULL) {
        grib_get_string(h, localDir_, localDir, &len);
    }

    len = 1024;
    if (extraDir_ != NULL && extraTable_ != NULL) {
        grib_get_string(h, extraDir_, extraDir, &len);
    }

    if (*masterDir != 0) {
        char name[2048] = {0,};
        snprintf(name, sizeof(name), "%s/%s", masterDir, tablename_);
        grib_recompose_name(h, NULL, name, recomposed, 0);
        filename = grib_context_full_defs_path(c, recomposed);
    }
    else {
        grib_recompose_name(h, NULL, tablename_, recomposed, 0);
        filename = grib_context_full_defs_path(c, recomposed);
    }

    if (*localDir != 0) {
        char localName[2048] = {0,};
        snprintf(localName, sizeof(localName), "%s/%s", localDir, tablename_);
        grib_recompose_name(h, NULL, localName, localRecomposed, 0);
        localFilename = grib_context_full_defs_path(c, localRecomposed);
    }

    if (*extraDir != 0) {
        char extraTable[2048] = {0,};
        snprintf(extraTable, sizeof(extraTable), "%s/%s", extraDir, extraTable_);
        grib_recompose_name(h, NULL, extraTable, extraRecomposed, 0);
        extraFilename = grib_context_full_defs_path(c, extraRecomposed);
    }

    next = c->smart_table;
    while (next) {
        if ((filename && next->filename[0] && strcmp(filename, next->filename[0]) == 0) &&
            ((localFilename == 0 && next->filename[1] == NULL) ||
             ((localFilename != 0 && next->filename[1] != NULL) && strcmp(localFilename, next->filename[1]) == 0)) &&
            ((extraFilename == 0 && next->filename[2] == NULL) ||
             ((extraFilename != 0 && next->filename[2] != NULL) && strcmp(extraFilename, next->filename[2]) == 0)))
            return next;
        next = next->next;
    }

    // Note: widthOfCode_ is chosen so that 2^width is bigger than the maximum descriptor code,
    //  which for BUFR4 is the Table C operator 243255
    //
    size = (1ULL << widthOfCode_);  // = 2^widthOfCode_ (as a 64 bit number)

    t = (grib_smart_table*)grib_context_malloc_clear_persistent(c, sizeof(grib_smart_table));
    t->entries = (grib_smart_table_entry*)grib_context_malloc_clear_persistent(c, size * sizeof(grib_smart_table_entry));
    t->numberOfEntries = size;

    if (filename != 0)
        grib_load_smart_table(c, filename, recomposed, size, t);

    if (localFilename != 0)
        grib_load_smart_table(c, localFilename, localRecomposed, size, t);

    if (extraFilename != 0)
        grib_load_smart_table(c, extraFilename, extraRecomposed, size, t);

    if (t->filename[0] == NULL && t->filename[1] == NULL) {
        grib_context_free_persistent(c, t);
        return NULL;
    }

    return t;
}

static int grib_load_smart_table(grib_context* c, const char* filename,
                                 const char* recomposed_name, size_t size, grib_smart_table* t)
{
    char line[1024] = {0,};
    FILE* f = NULL;
    // int lineNumber;
    int numberOfColumns, code;

    grib_context_log(c, GRIB_LOG_DEBUG, "Loading code table from %s", filename);

    f = codes_fopen(filename, "r");
    if (!f)
        return GRIB_IO_PROBLEM;

    ECCODES_ASSERT(t != NULL);

    if (t->filename[0] == NULL) {
        t->filename[0]        = grib_context_strdup_persistent(c, filename);
        t->recomposed_name[0] = grib_context_strdup_persistent(c, recomposed_name);
        t->next               = c->smart_table;
        t->numberOfEntries    = size;
        {
            eccodes::sync::LockGuard<eccodes::sync::Mutex> lock(mutex);
            c->smart_table = t;
        }
    }
    else if (t->filename[1] == NULL) {
        t->filename[1]        = grib_context_strdup_persistent(c, filename);
        t->recomposed_name[1] = grib_context_strdup_persistent(c, recomposed_name);
    }
    else {
        t->filename[2]        = grib_context_strdup_persistent(c, filename);
        t->recomposed_name[2] = grib_context_strdup_persistent(c, recomposed_name);
    }

    // lineNumber = 0;
    while (fgets(line, sizeof(line) - 1, f)) {
        char* s = line;
        char* p;

        line[strlen(line) - 1] = 0;

        // ++lineNumber;
        while (*s != '\0' && isspace(*s))
            s++;

        if (*s == '#')
            continue;

        p = s;
        while (*p != '\0' && *p != '|')
            p++;

        *p = 0;

        code = atoi(s);

        p++;
        s = p;
        while (*p != '\0' && *p != '|')
            p++;

        *p = 0;

        numberOfColumns = 0;
        // The highest possible descriptor code must fit into t->numberOfEntries
        DEBUG_ASSERT(code < t->numberOfEntries);
        while (*s) {
            char* tcol = t->entries[code].column[numberOfColumns];
            if (tcol) grib_context_free_persistent(c, tcol);
            t->entries[code].column[numberOfColumns] = grib_context_strdup_persistent(c, s);
            numberOfColumns++;
            DEBUG_ASSERT(numberOfColumns < MAX_SMART_TABLE_COLUMNS);

            p++;
            s = p;
            while (*p != '\0' && *p != '|')
                p++;
            *p = 0;
        }
    }

    fclose(f);
    return 0;
}

void SmartTable::dump(eccodes::Dumper* dumper)
{
    dumper->dump_long(this, NULL);
}

int SmartTable::unpack_string(char* buffer, size_t* len)
{
    grib_smart_table* table = NULL;

    size_t size = 1;
    long value;
    int err = GRIB_SUCCESS;
    char tmp[1024];
    size_t l = 0;

    if ((err = unpack_long(&value, &size)) != GRIB_SUCCESS)
        return err;

    if (!table_)
        table_ = load_table();
    table = table_;

    if (table && (value >= 0) && (value < table->numberOfEntries) && table->entries[value].abbreviation) {
        strcpy(tmp, table->entries[value].abbreviation);
    }
    else {
        snprintf(tmp, sizeof(tmp), "%d", (int)value);
    }

    l = strlen(tmp) + 1;

    if (*len < l) {
        *len = l;
        return GRIB_BUFFER_TOO_SMALL;
    }

    strcpy(buffer, tmp);
    *len   = l;
    dirty_ = 0;

    return GRIB_SUCCESS;
}

int SmartTable::get_table_codes()
{
    size_t size = 0;
    long* v     = 0;
    int err     = 0;
    int count, j;
    size_t i;

    int table_size;

    if (!dirty_)
        return 0;

    table_size = (1 << widthOfCode_);  // 2 ^ widthOfCode_

    if (!table_)
        table_ = load_table();

    err = grib_get_size(get_enclosing_handle(), values_, &size);
    if (err) {
        grib_context_log(context_, GRIB_LOG_ERROR,
                         "unable to get size of %s", name_);
        return err;
    }

    v = (long*)grib_context_malloc_clear(context_, size * sizeof(long));

    grib_get_long_array(get_enclosing_handle(), values_, v, &size);

    count = 0;
    for (i = 0; i < size; i++) {
        if (v[i] < table_size)
            count++;
    }
    if (tableCodes_)
        grib_context_free(context_, tableCodes_);
    tableCodes_ = (long*)grib_context_malloc_clear(context_, count * sizeof(long));
    j = 0;
    for (i = 0; i < size; i++) {
        if (v[i] < table_size)
            tableCodes_[j++] = v[i];
    }

    grib_context_free(context_, v);

    tableCodesSize_ = count;
    dirty_ = 0;

    return 0;
}

int SmartTable::value_count(long* count)
{
    int err = 0;
    *count  = 0;

    if (!values_)
        return 0;
    err = get_table_codes();
    if (err)
        return err;

    *count = tableCodesSize_;
    return GRIB_SUCCESS;
}

void SmartTable::destroy(grib_context* context)
{
    if (vvalue_ != NULL) {
        grib_context_free(context, vvalue_);
        vvalue_ = NULL;
    }
    if (tableCodes_)
        grib_context_free(context_, tableCodes_);

    Unsigned::destroy(context);
}

long SmartTable::get_native_type()
{
    int type = GRIB_TYPE_LONG;
    // printf("---------- %s flags=%ld GRIB_ACCESSOR_FLAG_STRING_TYPE=%d\n",
    //         a->name,flags_ ,GRIB_ACCESSOR_FLAG_STRING_TYPE);
    if (flags_ & GRIB_ACCESSOR_FLAG_STRING_TYPE)
        type = GRIB_TYPE_STRING;
    return type;
}

int SmartTable::unpack_long(long* val, size_t* len)
{
    int err = 0;
    size_t i;

    if (!values_)
        return 0;

    err = get_table_codes();
    if (err)
        return 0;

    if (*len < tableCodesSize_) {
        grib_context_log(context_, GRIB_LOG_ERROR,
                         "Wrong size (%zu) for %s, it contains %zu values", *len, name_, tableCodesSize_);
        *len = tableCodesSize_;
        return GRIB_ARRAY_TOO_SMALL;
    }

    for (i = 0; i < tableCodesSize_; i++)
        val[i] = tableCodes_[i];

    return err;
}

}  // namespace eccodes::accessor
