yuml-diagram/src/utils/yuml2dot-utils.js

UML diagramming package based on the yUML syntax

const getRGB = require('./rgb.js');

module.exports = function()
{
    var colorTable = null;
    const ESCAPED_CHARS = 
    {
        "\n": "<BR/>",
        "&": "&amp;",
        "<": "&lt;",
        ">": "&gt;",
    };

    this.escape_label = function(label)
    {
        var newlabel = "";

        for (var i=0; i<label.length; i++)
            newlabel += replaceChar(label.charAt(i));

        function replaceChar(c)
        {
            c = c.replace('{', '\\{').replace('}', '\\}');
            c = c.replace(';', '\n');
            c = c.replace('<', '\\<').replace('>', '\\>');
            // c = c.replace('\\n\\n', '\\n');
            return c;
        }

        return newlabel;
    }

    this.unescape_label = function(label)
    {
        var newlabel = label.replace(/\\\{/g, '{').replace(/\\\}/g, '}');
        newlabel = newlabel.replace(/\\</g, '<').replace(/\\>/g, '>');

        return newlabel;
    }

    this.splitYumlExpr = function(line, separators, escape = "\\")
    {
        var word = "";
        var lastChar = null;
        var parts = [];

        for (var i=0; i<line.length; i++)
        {
            c = line[i];

            if (c === escape && i + 1 < line.length)
            {
                word += c;
                word += line[++i];
            }
            else if (separators.indexOf(c) >= 0 && lastChar === null)
            {
                if (word.length > 0) {
                    parts.push(word.trim());
                    word = "";
                }

                switch (c)
                {
                    case '[':
                        lastChar = ']'; break;
                    case '(':
                        lastChar = ')'; break;
                    case '<':
                        lastChar = '>'; break;
                    case '|':
                        lastChar = '|'; break;
                    default:
                        lastChar = null; break;
                }
                word = c;
            }
            else if (c === lastChar)
            {
                lastChar =  null;
                parts.push(word.trim() + c);
                word = "";
            }
            else
            {
                word += c;
            }
        }

        if (word.length > 0)
            parts.push(word.trim());

        return parts;
    }

    this.extractBgAndNote = function(part, allowNote)
    {
        var ret = { bg: "", isNote: false, luma: 128 };

        var bgParts = /^(.*)\{ *bg *: *([a-zA-Z]+\d*|#[0-9a-fA-F]{6}) *\}$/.exec(part);
        if (bgParts != null && bgParts.length == 3)
        {
            ret.part = bgParts[1].trim();
            ret.bg = bgParts[2].trim().toLowerCase();

            var luma = getLuma(ret.bg);
            if (luma < 64)
                ret.fontcolor = "white";
            else if (luma > 192)
                ret.fontcolor = "black";
        }
        else
            ret.part = part.trim();

        if (allowNote && part.startsWith("note:"))
        {
            ret.part = ret.part.substring(5).trim();
            ret.isNote = true;
        }
        return ret;
    }

    this.escape_token_escapes = function(spec)
    {
        return spec.replace('\\[', '\\u005b').replace('\\]', '\\u005d');
    }

    this.unescape_token_escapes = function(spec)
    {
        return spec.replace('\\u005b', '[').replace('\\u005d', ']');
    }

    this.recordName = function(label)
    {
        return label.split("|")[0].trim();
    }

    this.formatLabel = function(label, wrap, allowDivisors)
    {
        label = label.trim();

        var lines = [label];

        if (allowDivisors && label.indexOf("|") >= 0)
            lines = label.split('|');

        for (var j=0; j<lines.length; j++)
        {
            if (j==0 || !allowDivisors)
            {
                lines[j] = wordwrap(lines[j], wrap, "\n");
            }
            else
            {
                if (!lines[j].endsWith(";"))
                    lines[j] += ";";

                lines[j] = lines[j].replaceAll(";", "\\l");
            }
        }

        label = lines.join('|');

        return escape_label(label);
    }

    this.wordwrap = function(str, width, newline)
    {
        if (!str || str.length<width)
            return str;

        var p;
        for (p = width; p>0 && str[p]!=' '; p--) { }

        if (p > 0) 
        {
            var left = str.substring(0, p);
            var right = str.substring(p+1);
            return left + newline + this.wordwrap(right, width, newline);
        }

        return str;
    }

    this.serializeDot = function(obj, rankdir)
    {
          return "[" + Object.keys(obj).map(key => `${key}=` + ("string" === typeof obj[key] ? `"${obj[key]}"` : obj[key])).join(" , ") + " ]";
    }

    this.serializeDotElements = function(arr)
    {
        var dot = "";

        for (var i=0; i<arr.length; i++)
        {
            var record = arr[i];

            if (record.length == 2)
                dot += '    ' + record[0] + ' ' + serializeDot(record[1]) + "\r\n";
            else if (record.length == 3)
                dot += '    ' + record[0] + " -> " + record[1] + ' ' + serializeDot(record[2]) + "\r\n";
        }

        return dot;
    }

    this.buildDotHeader = function(isDark)
    {
        var colors = isDark ? "color=white, fontcolor=white" : "color=black, fontcolor=black";

        var header = "digraph G {\r\n" 
            + "  graph [ bgcolor=transparent, fontname=Helvetica ]\r\n"
            + "  node [ shape=none, margin=0, " + colors + ", fontname=Helvetica ]\r\n"
            + "  edge [ " + colors + ", fontname=Helvetica ]\r\n";

        return header;
    }

    loadColors = function()
    {
        if (colorTable != null)
            return;
        else
            colorTable = {};

        var rgb = getRGB();

        for (var i=0; i<rgb.length; i++)
        {
            var parts = /^(\d+) (\d+) (\d+) (.*)$/.exec(rgb[i]);

            if (parts != null && parts.length == 5 && parts[4].indexOf(' ') < 0)
            {
                var luma = 0.2126 * parseFloat(parts[0]) + 0.7152 * parseFloat(parts[1]) + 0.0722 * parseFloat(parts[2]);
                colorTable[parts[4].toLowerCase()] = luma;                
            }
        }
    }

    getLuma = function(color)
    {
        loadColors();
        var luma = 128;

        if (color.startsWith('#'))
            luma = 0.2126 * parseInt(color.substr(1,2), 16) + 0.7152 * parseInt(color.substr(3,2), 16) + 0.0722 * parseInt(color.substr(5,2), 16);
        else if (colorTable.hasOwnProperty(color))
            luma = colorTable[color];

        return luma;
    }
}