#include "SoilMoistureIo.h"
#include "apps.h"
#include <fstream>
#include <sys/stat.h>

namespace trygvis {
namespace apps {

using namespace std;
using namespace trygvis::apps;
using namespace trygvis::soil_moisture;
namespace po = boost::program_options;

class TimestampFixingSampleOutputStream : public SampleOutputStream {

public:
    TimestampFixingSampleOutputStream(string timestamp_name, string now_name, time_t start_time, shared_ptr<SampleOutputStream> output) :
            timestamp_name_(timestamp_name), now_name_(now_name), start_time_(start_time), output_(output) {
    }

    virtual void write(Sample sample) override {
        long relative_time = sample.lexical_at<long>(now_name_);

        string new_value = std::to_string(start_time_ + relative_time);
        sample.set(timestamp_name_, new_value);

        output_->write(sample);
    };

private:
    string now_name_, timestamp_name_;
    time_t start_time_;
    shared_ptr<SampleOutputStream> output_;
};

class sample_timestamp : public app {

private:
    string input_file, timestamp_name, now_name;

public:
    sample_timestamp() : input_file("") {
    }

    void add_options(po::options_description_easy_init &options) override {
        options
                ("help", "produce this help message")
                ("input", po::value<string>(&input_file)->required())
                ("now-name", po::value<string>(&now_name)->default_value("now"))
                ("timestamp-name", po::value<string>(&timestamp_name)->default_value("timestamp"));
    }

    int main(app_execution &execution) override {
        ifstream input(input_file, std::ifstream::in | std::ifstream::binary);

        if (input.fail()) {
            cerr << "Could not open file: " << input_file << endl;
            return EXIT_FAILURE;
        }

        const int buffer_size = 100;

        input.seekg(-buffer_size, ios_base::end);

        struct stat buf;

        if (stat(input_file.c_str(), &buf)) {
            cerr << "stat failed" << endl;
            return EXIT_FAILURE;
        }

        auto sample_buffer = make_shared<VectorSampleOutputStream>();
        unique_ptr<SampleStreamParser> parser = open_sample_input_stream(sample_buffer);
        while (!input.eof()) {
            char buffer[buffer_size];
            input.read(buffer, buffer_size);

            if (input.bad()) {
                cerr << "Error reading input" << endl;
                return EXIT_FAILURE;
            }

            size_t count = (size_t) input.gcount();

            mutable_buffers_1 b = boost::asio::buffer(buffer, count);
            parser->process(b);
        }

        if (sample_buffer->samples.empty()) {
            cerr << "Could not find any samples" << endl;
            return EXIT_FAILURE;
        }

        time_t end_time = buf.st_mtim.tv_sec;

        Sample sample = *--sample_buffer->samples.end();

        string s;
        try {
            s = sample.at(now_name);
        } catch (out_of_range &e) {
            cerr << "Missing key '" + now_name + "'." << endl;
            return EXIT_FAILURE;
        }

        long now;
        try {
            now = boost::lexical_cast<long>(s);
        } catch (const boost::bad_lexical_cast &e) {
            cerr << "Bad integer value '" + s + "'." << endl;
            return EXIT_FAILURE;
        }

        time_t start_time = end_time - now;
        cerr << "end_time   " << end_time << endl;
        cerr << "now        " << now << endl;
        cerr << "start_time " << start_time << endl;

        // Restart the reading of the input file and add the adjusted timestamp
        input.clear(ios::eofbit);
        input.seekg(0);
        if(input.fail()) {
            cerr << "Coult not seek input file" << endl;
            return EXIT_FAILURE;
        }

        auto output_stream = open_sample_output_stream(parser->type(), unique_ptr<ostream>(&cout));
        auto p = make_shared<TimestampFixingSampleOutputStream>("timestamp", now_name, start_time, move(output_stream));
        parser = open_sample_input_stream(p, parser->type());

        int recordCount = 0;

        while (!input.eof()) {
            char buffer[buffer_size];

            size_t gcount = (size_t)input.readsome(buffer, buffer_size);

            recordCount++;

            mutable_buffers_1 b = boost::asio::buffer(buffer, gcount);
            parser->process(b);
        }

        return EXIT_SUCCESS;
    }
};

}
}

using namespace trygvis::apps;

int main(int argc, char *argv[]) {
    sample_timestamp app;
    return launch_app(argc, argv, app);
}