The Monster Trivia Converter

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    <title>The Trivia Monster Converter</title>
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    <h1>The Trivia Monster Converter</h1>

    <p>Converter for question files of the game „The Trivia Monster“ by Paul
    Norman, published 1984 by Cosmi, for the C64.</p>

    <p>The program displays general hints for the answers while loading the main
    program:</p>

<pre>
    HINTS FOR ANSWERING QUESTIONS:

    DO NOT USE 'THE' IN YOUR ANSWERS
    UNLESS IT IS A BOOK OR FILM TITLE.
    SPELL ALL NUMBER ANSWERS AND HYPHENATE
    TWO-DIGIT NUMBERS. UNLESS OTHERWISE
    INDICATED BY (NO.)
    USE FULL NAMES AS COMMONLY KNOWN
    UNLESS THE QUESTION ASKS FOR (LST.NM)
    OR IF ONLY LAST NAMES ARE IN USED TRIVIA
</pre>

    <p>So it makes sense to write the questions and answers accordingly.</p>

    <h2>Example of an entry</h2>

<pre>
    2AWHAT IS THE BEST, MOST SELLING HOME
    COMPUTER OF ALL TIMES?
    COMMODORE SIXTY-FOUR
</pre>

    <p>Lines are max. 40&nbsp;characters long.  Three lines per entry.</p>

    <p><code>2</code> is the category.  Followed by a character between
    <code>A</code> and <code>C</code> which I don't know the meaning of yet.
    Then follows the question in the first two lines.  And finally the answer in
    the last line.</p>

    <p>Each file has 135&nbsp;entries with three lines each = 135&centerdot;3 =
    405&nbsp;lines in total.</p>

    <h2>Categories</h2>
    <p>
        <ol>
            <li>Science</li>
            <li>History</li>
            <li>Sports</li>
            <li>Grabbag</li>
            <li>The Arts</li>
            <li>Showbizz</li>
        </ol>
    </p>

    <h2>Converter</h2>

    <p>Enter/copy 405 lines of ASCII text in the expected format.  Upper or
    lower case doesn't matter, it ends up being upper case after the
    conversion.</p>

    <p>
        <textarea id="text" cols="40" rows="25" placeholder="Questions and Answers&hellip;">
        </textarea>
        <button onclick="convert()">Convert</button>
    </p>
    <hr>

    <small>Version 0.1 &bullet; &copy; 2026 by BlackJack/Civitas &bullet; HTML5
    & Vanilla JS</small>

    <script>
        const START_ADDRESS = 0x6000;
        const END_ADDRESS = 0x9F80;
        const ENTRY_COUNT = 135;
        const LINES_PER_ENTRY = 3;
        const LINE_COUNT = ENTRY_COUNT * LINES_PER_ENTRY;

        function convert() {
            let lines = document.getElementById("text").value.trim().split("\n");
            if (lines.length != LINE_COUNT) {
                alert(`Expected ${LINE_COUNT} lines, got ${lines.length} instead!`);
                return;
            }

            for (let i = 0; i < lines.length; i += 3) {
                const line = lines[i];
                const category = line[0];
                if (category < 1 || category > 6) {
                    alert(`Line ${i + 1}: Unexpected category: ${category}!`);
                    return;
                }
                // TODO: Check unkown second character.
            }

            lines = lines.map((line) => line.trim());
            for (let i = 0; i < lines.length; i++) {
                const line = lines[i];
                if (line.length > 40) {
                    alert(`Line ${i + 1}: length limit exceeded: ${line.length}.`);
                    return;
                }
            }

            const data = (new Uint8Array(END_ADDRESS - START_ADDRESS + 2)).fill(32);
            data[0] = START_ADDRESS % 256;
            data[1] = Math.floor(START_ADDRESS / 256);
            const encoder = new TextEncoder();
            for (let i = 0; i < lines.length; i++) {
                const line = encoder.encode(lines[i]);
                for (let j = 0; j < line.length; j++) {
                    let value = line[j];
                    if (value >= 128) {
                        alert(`Line ${i + 1}: character outside ASCII.`);
                        return;
                    } else if (value >= 96) {
                        value -= 96;
                    } else if (value >= 64) {
                        value -= 64;
                    }
                    line[j] = value;
                }
                data.set(line, 2 + i * 40);
            }

            const blob = new Blob([data], { type: "application/octet-stream" });
            const url = URL.createObjectURL(blob);
            const link = document.createElement("a");
            link.href = url;
            link.download = "1prg";
            document.body.appendChild(link);
            link.click();
            document.body.removeChild(link);
            URL.revokeObjectURL(url);
        }
    </script>
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