// data source: http://www.gutenberg.org/cache/epub/1342/pg1342.txt

alphabet = 'abcdefghijklmnopqrstuvwxyz'.split('');
keys = {};
for (var i = 0; i < alphabet.length; ++i)
{
    keys[alphabet[i]] = i;
}

dataset = [];
for (var i = 0; i < alphabet.length; ++i)
{
    dataset.push(0);
}

d3.text("z_pride_and_prejudice.txt", "text/plain", function(error, text) {
    words = text.split(" ");
    words.forEach(function(word) {
        word = word.toLowerCase();
        if (word.charAt(0).match(/[a-z]/))
        {
            dataset[keys[word.charAt(0)]] += 1;
        }
    });

    var padding = 5;
    var svgWidth = 250;
    var svgHeight = 250;
    var nCols = 4;
    var nRows = Math.ceil(alphabet.length / nCols);
    var svg = d3.select("body")
        .append("svg")
        .attr("width", svgWidth)
        .attr("height", svgHeight)
        .attr("id", "canvas");

    var tileWidth = svgWidth / nCols;
    var tileHeight = svgHeight / nRows;

    tiles = svg.selectAll(".tile")
        .data(dataset)
        .enter()
        .append("g")
        .attr("transform", function(d, i) {
            var x = tileWidth * (i % nCols);
            var y = tileHeight * Math.floor(i / nCols);
            return "translate(" + x + "," + y + ")";
        })
        .attr("class", "tile");

    tiles.append("rect")
        .attr("x", 0)
        .attr("y", 0)
        .attr("width", tileWidth)
        .attr("height", tileHeight)
        .attr("style", "fill: none;");

    var yCenter = tileHeight / 1.65;
    var xOffset = 10.0;
    tiles.append("text")
        .text(function(d, i) { 
            return alphabet[i].toUpperCase() + " : " + d; 
        })
        .attr("transform", "translate(" + xOffset + "," + yCenter + ")");
});