// Licensed to the Apache Software Foundation (ASF) under one

// or more contributor license agreements.  See the NOTICE file

// distributed with this work for additional information

// regarding copyright ownership.  The ASF licenses this file

// to you under the Apache License, Version 2.0 (the

// "License"); you may not use this file except in compliance

// with the License.  You may obtain a copy of the License at

//

//   http://www.apache.org/licenses/LICENSE-2.0

//

// Unless required by applicable law or agreed to in writing,

// software distributed under the License is distributed on an

// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY

// KIND, either express or implied.  See the License for the

// specific language governing permissions and limitations

// under the License.

#include "util/url_parser.h"

#include <ctype.h>

#include <stdint.h>

#include <algorithm>

#include <string>

#include "core/string_ref.h"

#include "util/string_search.hpp"

namespace doris {

const StringRef UrlParser::_s_url_authority("AUTHORITY", 9);

const StringRef UrlParser::_s_url_file("FILE", 4);

const StringRef UrlParser::_s_url_host("HOST", 4);

const StringRef UrlParser::_s_url_path("PATH", 4);

const StringRef UrlParser::_s_url_protocol("PROTOCOL", 8);

const StringRef UrlParser::_s_url_query("QUERY", 5);

const StringRef UrlParser::_s_url_ref("REF", 3);

const StringRef UrlParser::_s_url_userinfo("USERINFO", 8);

const StringRef UrlParser::_s_url_port("PORT", 4);

const StringRef UrlParser::_s_protocol("://", 3);

const StringRef UrlParser::_s_at("@", 1);

const StringRef UrlParser::_s_slash("/", 1);

const StringRef UrlParser::_s_colon(":", 1);

const StringRef UrlParser::_s_question("?", 1);

const StringRef UrlParser::_s_hash("#", 1);

const StringSearch UrlParser::_s_protocol_search(&_s_protocol);

const StringSearch UrlParser::_s_at_search(&_s_at);

const StringSearch UrlParser::_s_slash_search(&_s_slash);

const StringSearch UrlParser::_s_colon_search(&_s_colon);

const StringSearch UrlParser::_s_question_search(&_s_question);

const StringSearch UrlParser::_s_hash_search(&_s_hash);

bool UrlParser::parse_url(const StringRef& url, UrlPart part, StringRef* result) {

    result->data = nullptr;

    result->size = 0;

    // Remove leading and trailing spaces.

    StringRef trimmed_url = url.trim();

    // All parts require checking for the _s_protocol.

    int32_t protocol_pos = _s_protocol_search.search(&trimmed_url);

    if (protocol_pos < 0) {

        return false;

    }

    // Positioned to first char after '://'.

    StringRef protocol_end = trimmed_url.substring(protocol_pos + _s_protocol.size);

    switch (part) {

    case AUTHORITY: {

        // Find first '/'.

        int32_t end_pos = _s_slash_search.search(&protocol_end);

        *result = protocol_end.substring(0, end_pos);

        break;

    }

    case FILE:

    case PATH: {

        // Find first '/'.

        int32_t start_pos = _s_slash_search.search(&protocol_end);

        if (start_pos < 0) {

            // Return empty string. This is what Hive does.

            return true;

        }

        StringRef path_start = protocol_end.substring(start_pos);

        int32_t end_pos;

        if (part == FILE) {

            // End _s_at '#'.

            end_pos = _s_hash_search.search(&path_start);

        } else {

            // End string _s_at next '?' or '#'.

            end_pos = _s_question_search.search(&path_start);

            if (end_pos < 0) {

                // No '?' was found, look for '#'.

                end_pos = _s_hash_search.search(&path_start);

            }

        }

        *result = path_start.substring(0, end_pos);

        break;

    }

    case HOST: {

        // Find '@'.

        int32_t start_pos = _s_at_search.search(&protocol_end);

        if (start_pos < 0) {

            // No '@' was found, i.e., no user:pass info was given, start after _s_protocol.

            start_pos = 0;

        } else {

            // Skip '@'.

            start_pos += _s_at.size;

        }

        StringRef host_start = protocol_end.substring(start_pos);

        // Find first '?'.

        int32_t query_start_pos = _s_question_search.search(&host_start);

        if (query_start_pos > 0) {

            host_start = host_start.substring(0, query_start_pos);

        }

        // Find ':' to strip out port.

        int32_t end_pos = _s_colon_search.search(&host_start);

        if (end_pos < 0) {

            // No port was given. search for '/' to determine ending position.

            end_pos = _s_slash_search.search(&host_start);

        }

        *result = host_start.substring(0, end_pos);

        break;

    }

    case PROTOCOL: {

        *result = trimmed_url.substring(0, protocol_pos);

        break;

    }

    case QUERY: {

        // Find first '?'.

        int32_t start_pos = _s_question_search.search(&protocol_end);

        if (start_pos < 0) {

            // Indicate no query was found.

            return false;

        }

        StringRef query_start = protocol_end.substring(start_pos + _s_question.size);

        // End string _s_at next '#'.

        int32_t end_pos = _s_hash_search.search(&query_start);

        *result = query_start.substring(0, end_pos);

        break;

    }

    case REF: {

        // Find '#'.

        int32_t start_pos = _s_hash_search.search(&protocol_end);

        if (start_pos < 0) {

            // Indicate no user and pass were given.

            return false;

        }

        *result = protocol_end.substring(start_pos + _s_hash.size);

        break;

    }

    case USERINFO: {

        // Find '@'.

        int32_t end_pos = _s_at_search.search(&protocol_end);

        if (end_pos < 0) {

            // Indicate no user and pass were given.

            return false;

        }

        *result = protocol_end.substring(0, end_pos);

        break;

    }

    case PORT: {

        // Find '@'.

        int32_t start_pos = _s_at_search.search(&protocol_end);

        if (start_pos < 0) {

            // No '@' was found, i.e., no user:pass info was given, start after _s_protocol.

            start_pos = 0;

        } else {

            // Skip '@'.

            start_pos += _s_at.size;

        }

        StringRef host_start = protocol_end.substring(start_pos);

        // Find ':' to strip out port.

        int32_t end_pos = _s_colon_search.search(&host_start);

        //no port found

        if (end_pos < 0) {

            return false;

        }

        StringRef port_start_str = host_start.substring(end_pos + _s_colon.size);

        int32_t port_end_pos = _s_slash_search.search(&port_start_str);

        //if '/' not found, try to find '?'

        if (port_end_pos < 0) {

            port_end_pos = _s_question_search.search(&port_start_str);

        }

        *result = port_start_str.substring(0, port_end_pos);

        break;

    }

    case INVALID:

        return false;

    }

    return true;

}

bool UrlParser::parse_url_key(const StringRef& url, UrlPart part, const StringRef& key,

                              StringRef* result) {

    // Part must be query to ask for a specific query key.

    if (part != QUERY) {

        return false;

    }

    // Remove leading and trailing spaces.

    StringRef trimmed_url = url.trim();

    // Search for the key in the url, ignoring malformed URLs for now.

    StringSearch key_search(&key);

    while (trimmed_url.size > 0) {

        // Search for the key in the current substring.

        int32_t key_pos = key_search.search(&trimmed_url);

        bool match = true;

        if (key_pos < 0) {

            return false;

        }

        // Key pos must be != 0 because it must be preceded by a '?' or a '&'.

        // Check that the char before key_pos is either '?' or '&'.

        if (key_pos == 0 ||

            (trimmed_url.data[key_pos - 1] != '?' && trimmed_url.data[key_pos - 1] != '&')) {

            match = false;

        }

        // Advance substring beyond matching key.

        trimmed_url = trimmed_url.substring(key_pos + key.size);

        if (!match) {

            continue;

        }

        if (trimmed_url.size <= 0) {

            break;

        }

        // Next character must be '=', otherwise the match cannot be a key in the query part.

        if (trimmed_url.data[0] != '=') {

            continue;

        }

        int32_t pos = 1;

        // Find ending position of key's value by matching '#' or '&'.

        while (pos < trimmed_url.size) {

            switch (trimmed_url.data[pos]) {

            case '#':

            case '&':

                *result = trimmed_url.substring(1, pos - 1);

                return true;

            }

            ++pos;

        }

        // Ending position is end of string.

        *result = trimmed_url.substring(1);

        return true;

    }

    return false;

}

UrlParser::UrlPart UrlParser::get_url_part(const StringRef& part) {

    // Quick filter on requested URL part, based on first character.

    // Hive requires the requested URL part to be all upper case.

    std::string part_str = part.to_string();

    transform(part_str.begin(), part_str.end(), part_str.begin(), ::toupper);

    StringRef newPart = StringRef(part_str);

    switch (newPart.data[0]) {

    case 'A': {

        if (!newPart.eq(_s_url_authority)) {

            return INVALID;

        }

        return AUTHORITY;

    }

    case 'F': {

        if (!newPart.eq(_s_url_file)) {

            return INVALID;

        }

        return FILE;

    }

    case 'H': {

        if (!newPart.eq(_s_url_host)) {

            return INVALID;

        }

        return HOST;

    }

    case 'P': {

        if (newPart.eq(_s_url_path)) {

            return PATH;

        } else if (newPart.eq(_s_url_protocol)) {

            return PROTOCOL;

        } else if (newPart.eq(_s_url_port)) {

            return PORT;

        } else {

            return INVALID;

        }

    }

    case 'Q': {

        if (!newPart.eq(_s_url_query)) {

            return INVALID;

        }

        return QUERY;

    }

    case 'R': {

        if (!newPart.eq(_s_url_ref)) {

            return INVALID;

        }

        return REF;

    }

    case 'U': {

        if (!newPart.eq(_s_url_userinfo)) {

            return INVALID;

        }

        return USERINFO;

    }

    default:

        return INVALID;

    }

}

StringRef UrlParser::extract_url(StringRef url, StringRef name) {

    StringRef result("", 0);

    // Remove leading and trailing spaces.

    StringRef trimmed_url = url.trim();

    // find '?'

    int32_t question_pos = _s_question_search.search(&trimmed_url);

    if (question_pos < 0) {

        // this url no parameters.

        // Example: https://doris.apache.org/

        return result;

    }

    // find '#'

    int32_t hash_pos = _s_hash_search.search(&trimmed_url);

    StringRef sub_url;

    if (hash_pos < 0) {

        sub_url = trimmed_url.substring(question_pos + 1, trimmed_url.size - question_pos - 1);

    } else {

        sub_url = trimmed_url.substring(question_pos + 1, hash_pos - question_pos - 1);

    }

    // find '&' and '=', and extract target parameter

    // Example: k1=aa&k2=bb&k3=cc&test=dd

    int64_t and_pod;

    auto len = sub_url.size;

    StringRef key_url;

    while (true) {

        if (len <= 0) {

            break;

        }

        and_pod = sub_url.find_first_of('&');

        if (and_pod != -1) {

            key_url = sub_url.substring(0, and_pod);

            sub_url = sub_url.substring(and_pod + 1, len - and_pod - 1);

        } else {

            auto end_pos = sub_url.find_first_of('#');

            key_url = end_pos == -1 ? sub_url : sub_url.substring(0, end_pos);

            sub_url = result;

        }

        len = sub_url.size;

        auto eq_pod = key_url.find_first_of('=');

        if (eq_pod == -1) {

            // invalid url. like: k1&k2=bb

            continue;

        }

        auto key_len = key_url.size;

        auto key = key_url.substring(0, eq_pod);

        if (name == key) {

            return key_url.substring(eq_pod + 1, key_len - eq_pod - 1);

        }

    }

    return result;

}

} // namespace doris