#include "HTTPDictionarySource.h"
#include <DataStreams/IBlockOutputStream.h>
#include <DataStreams/formatBlock.h>
#include <IO/ConnectionTimeouts.h>
#include <IO/ConnectionTimeoutsContext.h>
#include <IO/ReadWriteBufferFromHTTP.h>
#include <IO/WriteBufferFromOStream.h>
#include <IO/WriteBufferFromString.h>
#include <IO/WriteHelpers.h>
#include <Formats/FormatFactory.h>
#include <Processors/Formats/IInputFormat.h>
#include <Interpreters/Context.h>
#include <Poco/Net/HTTPRequest.h>
#include <base/logger_useful.h>
#include "DictionarySourceFactory.h"
#include "DictionarySourceHelpers.h"
#include "DictionaryStructure.h"
#include "registerDictionaries.h"


namespace DB
{
namespace ErrorCodes
{
    extern const int LOGICAL_ERROR;
}

static const UInt64 max_block_size = 8192;


HTTPDictionarySource::HTTPDictionarySource(
    const DictionaryStructure & dict_struct_,
    const Configuration & configuration_,
    const Poco::Net::HTTPBasicCredentials & credentials_,
    Block & sample_block_,
    ContextPtr context_,
    bool created_from_ddl)
    : log(&Poco::Logger::get("HTTPDictionarySource"))
    , update_time(std::chrono::system_clock::from_time_t(0))
    , dict_struct(dict_struct_)
    , configuration(configuration_)
    , sample_block(sample_block_)
    , context(context_)
    , timeouts(ConnectionTimeouts::getHTTPTimeouts(context))
{
    if (created_from_ddl)
        context->getRemoteHostFilter().checkURL(Poco::URI(configuration.url));

    credentials.setUsername(credentials_.getUsername());
    credentials.setPassword(credentials_.getPassword());
}

HTTPDictionarySource::HTTPDictionarySource(const HTTPDictionarySource & other)
    : log(&Poco::Logger::get("HTTPDictionarySource"))
    , update_time(other.update_time)
    , dict_struct(other.dict_struct)
    , configuration(other.configuration)
    , sample_block(other.sample_block)
    , context(Context::createCopy(other.context))
    , timeouts(ConnectionTimeouts::getHTTPTimeouts(context))
{
    credentials.setUsername(other.credentials.getUsername());
    credentials.setPassword(other.credentials.getPassword());
}

Pipe HTTPDictionarySource::createWrappedBuffer(std::unique_ptr<ReadWriteBufferFromHTTP> http_buffer_ptr)
{
    Poco::URI uri(configuration.url);
    String http_request_compression_method_str = http_buffer_ptr->getCompressionMethod();
    auto in_ptr_wrapped
        = wrapReadBufferWithCompressionMethod(std::move(http_buffer_ptr), chooseCompressionMethod(uri.getPath(), http_request_compression_method_str));
    auto source = FormatFactory::instance().getInput(configuration.format, *in_ptr_wrapped, sample_block, context, max_block_size);
    source->addBuffer(std::move(in_ptr_wrapped));
    return Pipe(std::move(source));
}

void HTTPDictionarySource::getUpdateFieldAndDate(Poco::URI & uri)
{
    if (update_time != std::chrono::system_clock::from_time_t(0))
    {
        auto tmp_time = update_time;
        update_time = std::chrono::system_clock::now();
        time_t hr_time = std::chrono::system_clock::to_time_t(tmp_time) - configuration.update_lag;
        WriteBufferFromOwnString out;
        writeDateTimeText(hr_time, out);
        uri.addQueryParameter(configuration.update_field, out.str());
    }
    else
    {
        update_time = std::chrono::system_clock::now();
    }
}

Pipe HTTPDictionarySource::loadAll()
{
    LOG_TRACE(log, "loadAll {}", toString());
    Poco::URI uri(configuration.url);
    auto in_ptr = std::make_unique<ReadWriteBufferFromHTTP>(
        uri,
        Poco::Net::HTTPRequest::HTTP_GET,
        ReadWriteBufferFromHTTP::OutStreamCallback(),
        timeouts,
        0,
        credentials,
        DBMS_DEFAULT_BUFFER_SIZE,
        configuration.header_entries);

    return createWrappedBuffer(std::move(in_ptr));
}

Pipe HTTPDictionarySource::loadUpdatedAll()
{
    Poco::URI uri(configuration.url);
    getUpdateFieldAndDate(uri);
    LOG_TRACE(log, "loadUpdatedAll {}", uri.toString());
    auto in_ptr = std::make_unique<ReadWriteBufferFromHTTP>(
        uri,
        Poco::Net::HTTPRequest::HTTP_GET,
        ReadWriteBufferFromHTTP::OutStreamCallback(),
        timeouts,
        0,
        credentials,
        DBMS_DEFAULT_BUFFER_SIZE,
        configuration.header_entries);

    return createWrappedBuffer(std::move(in_ptr));
}

Pipe HTTPDictionarySource::loadIds(const std::vector<UInt64> & ids)
{
    LOG_TRACE(log, "loadIds {} size = {}", toString(), ids.size());

    auto block = blockForIds(dict_struct, ids);

    ReadWriteBufferFromHTTP::OutStreamCallback out_stream_callback = [block, this](std::ostream & ostr)
    {
        WriteBufferFromOStream out_buffer(ostr);
        auto output_stream = context->getOutputStreamParallelIfPossible(configuration.format, out_buffer, sample_block);
        formatBlock(output_stream, block);
    };

    Poco::URI uri(configuration.url);
    auto in_ptr = std::make_unique<ReadWriteBufferFromHTTP>(
        uri,
        Poco::Net::HTTPRequest::HTTP_POST,
        out_stream_callback,
        timeouts,
        0,
        credentials,
        DBMS_DEFAULT_BUFFER_SIZE,
        configuration.header_entries);

    return createWrappedBuffer(std::move(in_ptr));
}

Pipe HTTPDictionarySource::loadKeys(const Columns & key_columns, const std::vector<size_t> & requested_rows)
{
    LOG_TRACE(log, "loadKeys {} size = {}", toString(), requested_rows.size());

    auto block = blockForKeys(dict_struct, key_columns, requested_rows);

    ReadWriteBufferFromHTTP::OutStreamCallback out_stream_callback = [block, this](std::ostream & ostr)
    {
        WriteBufferFromOStream out_buffer(ostr);
        auto output_stream = context->getOutputStreamParallelIfPossible(configuration.format, out_buffer, sample_block);
        formatBlock(output_stream, block);
    };

    Poco::URI uri(configuration.url);
    auto in_ptr = std::make_unique<ReadWriteBufferFromHTTP>(
        uri,
        Poco::Net::HTTPRequest::HTTP_POST,
        out_stream_callback,
        timeouts,
        0,
        credentials,
        DBMS_DEFAULT_BUFFER_SIZE,
        configuration.header_entries);

    return createWrappedBuffer(std::move(in_ptr));
}

bool HTTPDictionarySource::isModified() const
{
    return true;
}

bool HTTPDictionarySource::supportsSelectiveLoad() const
{
    return true;
}

bool HTTPDictionarySource::hasUpdateField() const
{
    return !configuration.update_field.empty();
}

DictionarySourcePtr HTTPDictionarySource::clone() const
{
    return std::make_unique<HTTPDictionarySource>(*this);
}

std::string HTTPDictionarySource::toString() const
{
    Poco::URI uri(configuration.url);
    return uri.toString();
}

void registerDictionarySourceHTTP(DictionarySourceFactory & factory)
{
    auto create_table_source = [=](const DictionaryStructure & dict_struct,
                                   const Poco::Util::AbstractConfiguration & config,
                                   const std::string & config_prefix,
                                   Block & sample_block,
                                   ContextPtr global_context,
                                   const std::string & /* default_database */,
                                   bool created_from_ddl) -> DictionarySourcePtr {
        if (dict_struct.has_expressions)
            throw Exception(ErrorCodes::LOGICAL_ERROR, "Dictionary source of type `http` does not support attribute expressions");

        auto context = copyContextAndApplySettingsFromDictionaryConfig(global_context, config, config_prefix);

        const auto & settings_config_prefix = config_prefix + ".http";
        const auto & credentials_prefix = settings_config_prefix + ".credentials";

        Poco::Net::HTTPBasicCredentials credentials;

        if (config.has(credentials_prefix))
        {
            credentials.setUsername(config.getString(credentials_prefix + ".user", ""));
            credentials.setPassword(config.getString(credentials_prefix + ".password", ""));
        }

        const auto & headers_prefix = settings_config_prefix + ".headers";
        ReadWriteBufferFromHTTP::HTTPHeaderEntries header_entries;

        if (config.has(headers_prefix))
        {
            Poco::Util::AbstractConfiguration::Keys config_keys;
            config.keys(headers_prefix, config_keys);

            header_entries.reserve(config_keys.size());
            for (const auto & key : config_keys)
            {
                const auto header_key = config.getString(headers_prefix + "." + key + ".name", "");
                const auto header_value = config.getString(headers_prefix + "." + key + ".value", "");
                header_entries.emplace_back(std::make_tuple(header_key, header_value));
            }
        }

        auto configuration = HTTPDictionarySource::Configuration
        {
            .url = config.getString(settings_config_prefix + ".url", ""),
            .format =config.getString(settings_config_prefix + ".format", ""),
            .update_field = config.getString(settings_config_prefix + ".update_field", ""),
            .update_lag = config.getUInt64(settings_config_prefix + ".update_lag", 1),
            .header_entries = std::move(header_entries)
        };

        return std::make_unique<HTTPDictionarySource>(dict_struct, configuration, credentials, sample_block, context, created_from_ddl);
    };
    factory.registerSource("http", create_table_source);
}

}