File : core/FontSizeManager.js

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/*
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Copyright - 2017 2023 - wwwouaiebe - Contact: https://www.ouaie.be/
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This  program is free software;
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you can redistribute it and/or modify it under the terms of the
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GNU General Public License as published by the Free Software Foundation;
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either version 3 of the License, or any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
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*/
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/*
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Changes:
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    - v4.0.0:
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        - created from v3.6.0
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Doc reviewed 202208
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 */
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import theConfig from '../data/Config.js';
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/* ------------------------------------------------------------------------------------------------------------------------- */
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/**
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A simple container to store the font size
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*/
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/* ------------------------------------------------------------------------------------------------------------------------- */
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class FontSizeManager {
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    /**
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    The font size
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    @type {Number}
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    */
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    #fontSize;
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    /**
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    The constructor
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    */
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    constructor ( ) {
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        Object.freeze ( this );
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        // It's needed to initialize the fontSize in the increment or decrement functions because
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        // theFontSizeManager is a global object created before theConfig initialization
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        this.#fontSize = null;
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    }
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    /**
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    Increment the font size
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    */
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    increment ( ) {
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        if ( ! this.#fontSize ) {
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            this.#fontSize = theConfig.fontSize.initialValue;
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        }
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        this.#fontSize += theConfig.fontSize.incrementValue;
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        document.body.style [ 'font-size' ] = String ( this.#fontSize ) + 'mm';
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    }
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    /**
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    Decrement the font size
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    */
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    decrement ( ) {
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        if ( ! this.#fontSize ) {
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            this.#fontSize = theConfig.fontSize.initialValue;
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        }
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        this.#fontSize -= theConfig.fontSize.incrementValue;
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        document.body.style [ 'font-size' ] = String ( this.#fontSize ) + 'mm';
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    }
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}
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/* ------------------------------------------------------------------------------------------------------------------------- */
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/**
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The one and only one instance of FontSizeManager class
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@type {FontSizeManager}
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*/
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/* ------------------------------------------------------------------------------------------------------------------------- */
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const theFontSizeManager = new FontSizeManager ( );
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export default theFontSizeManager;
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/* --- End of file --------------------------------------------------------------------------------------------------------- */
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