/*
    Copyright (c) 2014-2016 Intel Corporation.  All Rights Reserved.

    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions
    are met:

      * Redistributions of source code must retain the above copyright
        notice, this list of conditions and the following disclaimer.
      * Redistributions in binary form must reproduce the above copyright
        notice, this list of conditions and the following disclaimer in the
        documentation and/or other materials provided with the distribution.
      * Neither the name of Intel Corporation nor the names of its
        contributors may be used to endorse or promote products derived
        from this software without specific prior written permission.

    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
    HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
    LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/


#include "offload_env.h"
#include <string.h>
#include <ctype.h>
#include "offload_util.h"
#include "liboffload_error_codes.h"

// for environment variables valid on all cards
const int MicEnvVar::any_card = -1;

MicEnvVar::~MicEnvVar()
{
    for (std::list<MicEnvVar::CardEnvVars*>::const_iterator
         it = card_spec_list.begin();
         it != card_spec_list.end(); it++) {
        CardEnvVars *card_data = *it;
        delete card_data;
    }
}

MicEnvVar::VarValue::~VarValue()
{
    free(env_var_value);
}

MicEnvVar::CardEnvVars::~CardEnvVars()
{
    for (std::list<MicEnvVar::VarValue*>::const_iterator it = env_vars.begin();
        it != env_vars.end(); it++) {
            VarValue *var_value = *it;
            delete var_value;
    }
}

// Searching for card in "card_spec_list" list with the same "number"

MicEnvVar::CardEnvVars* MicEnvVar::get_card(int number)
{
    if (number == any_card) {
        return &common_vars;
    }
    for (std::list<MicEnvVar::CardEnvVars*>::const_iterator
         it = card_spec_list.begin();
         it != card_spec_list.end(); it++) {
        CardEnvVars *card_data = *it;
        if (card_data->card_number == number) {
            return card_data;
        }
    }
    return NULL;
}

// Searching for environment variable in "env_var" list with the same name

MicEnvVar::VarValue* MicEnvVar::CardEnvVars::find_var(
    char* env_var_name,
    int env_var_name_length
)
{
    for (std::list<MicEnvVar::VarValue*>::const_iterator it = env_vars.begin();
        it != env_vars.end(); it++) {
            VarValue *var_value = *it;
            if (var_value->length == env_var_name_length &&
                !strncmp(var_value->env_var, env_var_name,
                         env_var_name_length)) {
                return var_value;
            }
    }
    return NULL;
}

void MicEnvVar::analyze_env_var(char *env_var_string)
{
    char          *env_var_name;
    char          *env_var_def;
    int           card_number;
    int           env_var_name_length;
    MicEnvVarKind env_var_kind;

    env_var_kind = get_env_var_kind(env_var_string,
                                    &card_number,
                                    &env_var_name,
                                    &env_var_name_length,
                                    &env_var_def);
    switch (env_var_kind) {
        case c_mic_var:
        case c_mic_card_var:
            add_env_var(card_number,
                        env_var_name,
                        env_var_name_length,
                        env_var_def);
            break;
        case c_mic_card_env:
            mic_parse_env_var_list(card_number, env_var_def);
            break;
        case c_no_mic:
        default:
            break;
    }
}

void MicEnvVar::add_env_var(
    int card_number,
    char *env_var_name,
    int env_var_name_length,
    char *env_var_def
)
{
    VarValue *var;
    CardEnvVars *card;

    // The case corresponds to common env var definition of kind
    // <mic-prefix>_<var>
    if (card_number == any_card) {
        card = &common_vars;
    }
    else {
        card = get_card(card_number);
        if (!card) {
            // definition for new card occurred
            card = new CardEnvVars(card_number);
            card_spec_list.push_back(card);
        }

    }
    var = card->find_var(env_var_name, env_var_name_length);
    if (!var) {
        // put new env var definition in "env_var" list
        var = new VarValue(env_var_name, env_var_name_length, env_var_def);
        card->env_vars.push_back(var);
    }
}

// The routine analyses string pointed by "env_var_string" argument
// according to the following syntax:
//
// Specification of prefix for MIC environment variables
// MIC_ENV_PREFIX=<mic-prefix>
//
// Setting single MIC environment variable
// <mic-prefix>_<var>=<value>
// <mic-prefix>_<card-number>_<var>=<value>

// Setting multiple MIC environment variables
// <mic-prefix>_<card-number>_ENV=<env-vars>

MicEnvVarKind MicEnvVar::get_env_var_kind(
    char *env_var_string,
    int *card_number,
    char **env_var_name,
    int *env_var_name_length,
    char **env_var_def
)
{
    int len = strlen(prefix);
    char *c = env_var_string;
    int num = 0;
    bool card_is_set = false;

    if (strncmp(c, prefix, len) != 0 || c[len] != '_') {
            return c_no_mic;
    }
    c += len + 1;

    *card_number = any_card;
    if (isdigit(*c)) {
        while (isdigit (*c)) {
            num = (*c++ - '0') + (num * 10);
        }
    if (*c != '_') {
        return c_no_mic;
    }
    c++;
        *card_number = num;
        card_is_set = true;
    }
    if (!isalpha(*c)) {
        return c_no_mic;
    }
    *env_var_name = *env_var_def = c;
    if (strncmp(c, "ENV=", 4) == 0) {
        if (!card_is_set) {
            *env_var_name_length = 3;
            *env_var_name = *env_var_def = c;
            *env_var_def = strdup(*env_var_def);
            if (*env_var_def == NULL)
                LIBOFFLOAD_ERROR(c_malloc);
            return  c_mic_var;
        }
        *env_var_def = c + strlen("ENV=");
        *env_var_def = strdup(*env_var_def);
        if (*env_var_def == NULL)
            LIBOFFLOAD_ERROR(c_malloc);
        return c_mic_card_env;
    }
    if (isalpha(*c)) {
        *env_var_name_length = 0;
        while (isalnum(*c) || *c == '_') {
            c++;
            (*env_var_name_length)++;
        }
    }
    if (*c != '=') {
        return c_no_mic;
    }
    *env_var_def = strdup(*env_var_def);
    if (*env_var_def == NULL)
        LIBOFFLOAD_ERROR(c_malloc);
    return card_is_set? c_mic_card_var : c_mic_var;
}

// analysing <env-vars> in form:
// <mic-prefix>_<card-number>_ENV=<env-vars>
// where:
//
// <env-vars>:
//                <env-var>
//                <env-vars> | <env-var>
//
// <env-var>:
//                variable=value
//                variable="value"
//                variable=

void MicEnvVar::mic_parse_env_var_list(
    int card_number, char *env_vars_def_list)
{
    char *c = env_vars_def_list;
    char *env_var_name;
    int  env_var_name_length;
    char *env_var_def;
    bool var_is_quoted;

    if (*c == '"') {
        c++;
    }
    while (*c != 0) {
        var_is_quoted = false;
        env_var_name = c;
        env_var_name_length = 0;
        if (isalpha(*c)) {
            while (isalnum(*c) || *c == '_') {
                c++;
                env_var_name_length++;
            }
        }
        else {
            LIBOFFLOAD_ERROR(c_mic_parse_env_var_list1);
            return;
        }
        if (*c != '=') {
            LIBOFFLOAD_ERROR(c_mic_parse_env_var_list2);
            return;
        }
        c++;

        if (*c == '"') {
            var_is_quoted = true;
            c++;
        }
        // Environment variable values that contain | will need to be escaped.
        while (*c != 0 && *c != '|' &&
               (!var_is_quoted || *c != '"'))
        {
            // skip escaped symbol
            if (*c == '\\') {
                c++;
            }
            c++;
        }
        if (var_is_quoted) {
            c++; // for "
            while (*c != 0 && *c != '|') {
                c++;
            }
        }

        int sz = c - env_var_name;
        env_var_def = (char*)malloc(sz);
        if (env_var_def == NULL)
          LIBOFFLOAD_ERROR(c_malloc);
        memcpy(env_var_def, env_var_name, sz);
        env_var_def[sz] = 0;

        if (*c == '|') {
            c++;
            while (*c != 0 && *c == ' ') {
                c++;
            }
        }
        add_env_var(card_number,
                    env_var_name,
                    env_var_name_length,
                    env_var_def);
    }
}

// Collect all definitions for the card with number "card_num".
// The returned result is vector of string pointers defining one
// environment variable. The vector is terminated by NULL pointer.
// In the beginning of the vector there are env vars defined as
// <mic-prefix>_<card-number>_<var>=<value>
// or
// <mic-prefix>_<card-number>_ENV=<env-vars>
// where <card-number> is equal to "card_num"
// They are followed by definitions valid for any card
// and absent in previous definitions.

char** MicEnvVar::create_environ_for_card(int card_num)
{
    VarValue *var_value;
    VarValue *var_value_find;
    CardEnvVars *card_data = get_card(card_num);
    CardEnvVars *card_data_common;
    std::list<char*> new_env;
    char **rez;

    if (!prefix) {
        return NULL;
    }
    // There is no personel env var definitions for the card with
    // number "card_num"
    if (!card_data) {
        return create_environ_for_card(any_card);
    }

    for (std::list<MicEnvVar::VarValue*>::const_iterator
         it = card_data->env_vars.begin();
         it != card_data->env_vars.end(); it++) {
        var_value = *it;
        new_env.push_back(var_value->env_var_value);
    }

    if (card_num != any_card) {
        card_data_common = get_card(any_card);
        for (std::list<MicEnvVar::VarValue*>::const_iterator
             it = card_data_common->env_vars.begin();
             it != card_data_common->env_vars.end(); it++) {
            var_value = *it;
            var_value_find = card_data->find_var(var_value->env_var,
                                                 var_value->length);
            if (!var_value_find) {
                new_env.push_back(var_value->env_var_value);
            }
        }
    }

    int new_env_size = new_env.size();
    rez = (char**) malloc((new_env_size + 1) * sizeof(char*));
    if (rez == NULL)
      LIBOFFLOAD_ERROR(c_malloc);
    std::copy(new_env.begin(), new_env.end(), rez);
    rez[new_env_size] = 0;
    return rez;
}