import singlog;

import core.stdc.stdlib : exit, EXIT_SUCCESS, EXIT_FAILURE;
import std.stdio, std.conv, std.path, std.file, std.format, std.regex, std.array, std.algorithm, std.uuid;

import source.database;
import source.sql;

enum {
    GROUP_THEME = 2,
    GROUP_THEME_TEXT = 5,
    GROUP_QUESTION = 7,
    GROUP_QUESTION_TEXT = 10,
    GROUP_ANSWER = 12,
    GROUP_ANSWER_TEXT = 15,
    GROUP_ANSWER_RIGHT = 17,
    GROUP_ANSWER_RIGHT_TEXT = 20,
    GROUP_IMAGE = 22,
    GROUP_IMAGE_NAME = 25,
}

int main(string[] args)
{
    log.level(log.level.debugging)
        .output(log.output.stdout.stderr)
        .color(true);

    const string pictures = "./images";

    string testFilePath;
    string databaseFile;

    if (args.length != 3) {
        log.e("Не было передано необходимое количество параметров для запуска программы");
        return EXIT_FAILURE;
    }

    databaseFile = args[1];
    testFilePath = args[2];

    const string pattern = "^((( |\\t)*\\#( |\\t)*)(.*[^\\s]))|((( |\\t)*\\?( |\\t)*)(.*[^\\s]))"
        ~ "|((( |\\t)*-( |\\t)*)(.*[^\\s]))|((( |\\t)*\\+( |\\t)*)(.*[^\\s]))|((( |\\t)*\\*( |\\t)*)(.*[^\\s]))$";
    
    File testFile;

    try {
        testFile = File(testFilePath, "r");
    } catch (Exception e) {
        log.w("Unable to open the test file " ~ testFilePath);
        log.e(e);
        return EXIT_FAILURE;
    }

    dbliteConnect(databaseFile);

    auto regular = regex(pattern, "m");

    struct Answer {
        int number;
        string text;
        bool truth;

        bool addToDB(int question_id) {
            int id = sqlAddNewAnswer(question_id, this.number, this.text, this.truth);

            if (!id)
                return false;

            return true;
        }
    }

    struct Question {
        int number;
        string text;
        Answer[int] answers;
        bool hasPicture;
        ubyte[] picture;
        string pictureName;
        int pictureSize;

        ulong count() {
            return answers.length;
        }

        bool isValid() {
            bool error = false;

            if (answers.length <= 1)
                error = true;

            if (hasPicture && pictureSize > 256)
                error = true;

            return !error;
        }

        bool addToDB(int topic_id) {
            int id = sqlAddNewQuestion(
                topic_id,
                this.number,
                this.text,
                this.hasPicture,
                this.picture,
                this.pictureName);

            if (!id)
                return false;
            
            foreach (answer; answers.byKeyValue.array.sort!((a, b) => a.key < b.key)) {
                if (!answer.value.addToDB(id))
                    return false;
            }

            return true;
        }
    }

    struct Theme {
        string text;
        Question[int] questions;

        ulong count() {
            return questions.length;
        }

        bool isValid() {
            return questions.length > 1;
        }

        bool addToDB() {
            if (!check())
                return false;

            int id = sqlAddNewTheme(this.text);

            if (!id)
                return false;
            
            foreach (question; this.questions.byKeyValue.array.sort!((a, b) => a.key < b.key)) {
                if (!question.value.addToDB(id))
                    return false;
            }

            return true;
        }

        void print() {
            writeln("Количество вопросов: %s".format(this.count()));

            foreach (question; this.questions.byKeyValue.array.sort!((a, b) => a.key < b.key)) {
                writeln("\tВопрос №%d: %s".format(question.key, question.value.text));
                if (question.value.hasPicture)
                    writeln("\tСодержит изображение: %s (%d kB)"
                        .format(question.value.pictureName, question.value.pictureSize));
                writeln("\tКоличество ответов: %d".format(question.value.count()));
                foreach (answer; question.value.answers.byKeyValue.array.sort!((a, b) => a.key < b.key)) {
                    writeln("\t\tОтвет №%d: %s".format(answer.key, answer.value.text));
                }
            }
        }

        bool check() {
            bool error = false;

            if (!this.isValid()) {
                writeln("Недостаточное количество вопросов: %d".format(this.count()));
                error = true;
            }
            
            if (!error) {
                foreach (question; this.questions.byKeyValue.array.sort!((a, b) => a.key < b.key)) {
                    if (!question.value.isValid()) {
                        writeln("Вопрос №%d \"%s\" содержит недостаточное количество ответов (%d) или большой (> 256 kB) размер изображения (%d kB)"
                            .format(question.key, question.value.text, question.value.count(), question.value.pictureSize));
                        error = true;
                    }

                    int truth;

                    foreach (answer; question.value.answers) {
                        if (answer.truth)
                            ++truth;
                    }

                    if (truth > 1) {
                        writeln("Вопрос №%d \"%s\" содержит более одного правильного ответа".format(
                            question.key, question.value.text
                        ));
                        error = true;
                    }
                }
            }
            return !error;
        }
    }

    Theme theme;

    int numQuestion;
    int numAnswer;

    while (!testFile.eof())
    {
        string line = testFile.readln();
        auto match = matchFirst(line, regular);

        if (match.length == 0)
            continue;

        if (match[GROUP_THEME].length)
        {
            theme.text = match[GROUP_THEME_TEXT];
            continue;
        }

        if (match[GROUP_QUESTION].length)
        {
            numAnswer = 0;
            theme.questions[++numQuestion] = Question(numQuestion, match[GROUP_QUESTION_TEXT]);
            continue;
        }

        if (match[GROUP_ANSWER].length)
        {
            theme.questions[numQuestion].answers[++numAnswer] = Answer(numAnswer, match[GROUP_ANSWER_TEXT], false);
            continue;
        }

        if (match[GROUP_ANSWER_RIGHT].length)
        {
            theme.questions[numQuestion].answers[++numAnswer] = Answer(numAnswer, match[GROUP_ANSWER_RIGHT_TEXT], true);
            continue;
        }

        if (match[GROUP_IMAGE].length)
        {
            string currentPicture = buildPath(pictures, match[GROUP_IMAGE_NAME]);
            if (currentPicture.exists) {
                auto picFile = File(currentPicture, "r");
                theme.questions[numQuestion].hasPicture = true;
                theme.questions[numQuestion].picture = cast(ubyte[])read(currentPicture);
                theme.questions[numQuestion].pictureName =
                    md5UUID(theme.questions[numQuestion].picture).to!string ~ currentPicture.extension;
                theme.questions[numQuestion].pictureSize = picFile.size().to!int / 1024;
            } else {
                log.e("Файл \"%s\" не найден".format(currentPicture));
            }
            
            continue;
        }
    }

    // theme.print();
    // theme.check();
    theme.addToDB();

    return EXIT_SUCCESS;
}