<?php

/**
 * @file
 * Hooks and helper functions for the d3_sankey_examples module.
 */

/* Hooks. */

/**
 * Implements hook_menu().
 */
function d3_sankey_examples_menu() {
  $items = array();

  // Uses d3_sankey module to create a sample Sankey chart.
  $items['d3/examples/sankey'] = array(
    'title' => 'Sankey chart',
    'description' => 'Uses d3_sankey module to create a sample Sankey chart.',
    'access callback' => TRUE,
    'page callback' => '_d3_sankey_examples_sankey',
    'type' => MENU_LOCAL_TASK,
  );

  return $items;
}

/* Menu callbacks. */

/**
 * Menu callback: Uses d3_sankey module to create a sample Sankey chart.
 */
function _d3_sankey_examples_sankey() {
  $chart = array(
    'type' => 'sankey',

    // This will be the HTML id attribute of the div that will contain the
    // chart.
    'id' => 'visualization',

    // You can (optionally) specify the type of Sankey chart:
    // - D3_SANKEY_SANKEYTYPE_DEFAULT will not "select" the nodes or link when a
    //   user hovers over them.
    // - D3_SANKEY_SANKEYTYPE_SELECTION will "select" a node or link when a user
    //   hovers over it, but that selection will be limited only to only one
    //   node/link - the one being hovered.
    // - D3_SANKEY_SANKEYTYPE_PATH will "select" a node or link, as well as any
    //   nodes or links connected to it when a user hovers over it.
    'sankeyType' => D3_SANKEY_SANKEYTYPE_PATH,

    // You can (optionally) specify the width and/or height of the chart in
    // pixels. These numbers must be positive integers. If you do not specify a
    // width, sankey.js will choose 700px. If you do not specify a height,
    // sankey.js will choose 400px.
    'width' => '700',
    'height' => '400',

    // You can (optionally) specify the width and padding of nodes. These
    // numbers must be positive integers. If you do not specify a nodeWidth,
    // sankey.js will choose 24px. If you do not specify a padding, sankey.js
    // will choose 8px.
    'nodeWidth' => 24,
    'nodePadding' => 8,

    // You can (optionally) choose whether or not to spread the nodes across the
    // full height of the chart. You must specify a boolean. If you do not set
    // this setting, sankey.js will assume that you want to do so, as that looks
    // better.
    //
    // See https://github.com/q-m/d3.chart.sankey for more information.
    'spread' => TRUE,

    // You can (optionally) specify how many additional times the Sankey library
    // should pass over the diagram to try to make things look better. You must
    // specify zero, or positive integer. Note that higher numbers will make the
    // chart take longer to render. If you do not set this setting, sankey.js
    // will assume 1.
    'iterations' => 1,

    // You can (optionally) specify how labels will be attached to nodes:
    // - D3_SANKEY_ALIGNLABEL_AUTO will align node labels automatically. You
    //   probably want this alignment unless you are prepared to write custom
    //   CSS to handle labels overflowing one side of the diagram and being
    //   clipped.
    // - D3_SANKEY_ALIGNLABEL_START will align node labels to the start of paths
    //   connecting from them. In LTR languages, this setting will result in the
    //   labels for the right-most column of nodes overflowing on the right-hand
    //   side of the chart; default CSS causes these labels to be clipped (i.e.:
    //   not visible).
    // - D3_SANKEY_ALIGNLABEL_END will align node labels to the end of paths
    //   connecting to them. In LTR languages, this setting will result in the
    //   labels for the left-most column of nodes overflowing on the left-hand
    //   side of the chart; default CSS causes these labels to be clipped (i.e.:
    //   not visible).
    'alignLabel' => D3_SANKEY_ALIGNLABEL_AUTO,

    // The nodes are the boxes that appear in the diagram. You can define each
    // node as an associative PHP array (which will get turned into a JS
    // object). The D3, d3-plugins-sankey, d3.chart, and d3.chart.sankey source
    // code does not explicitly specify what keys are valid in node objects, but
    // the following keys are known to work:
    // - 'name' (optional): A label for the node.
    // - 'id' (optional): An SVG ID attribute (similar to an HTML ID attribute)
    //   to add to the node.
    //
    // It is important to note that the Sankey charting library *only identifies
    // nodes using their array index*: you cannot use the 'id' attribute to
    // define links between nodes! I have explicitly set the array indicies in
    // the example below, but you don't need to.
    //
    // Note also that the Sankey charting library arranges nodes on the page
    // based on how they link together (see the 'links' key below); you do not
    // get control over this!
    //
    // The order that you specify the nodes doesn't really affect the final
    // layout, but does matter, because their index is what you use to define
    // the links between them (see below). You will probably want to add nodes
    // to the bottom of the array so that you don't have to re-calculate all the
    // link sources/targets.
    'nodes' => array(
      0 => array('name' => 'Revenue', 'id' => 'revenue'),
      1 => array('name' => 'New work', 'id' => 'lob_new_work'),
      2 => array('name' => 'Service level agreements', 'id' => 'lob_sla'),
      3 => array('name' => 'Tech support', 'id' => 'lob_techsupport'),
      4 => array('name' => 'Client 1', 'id' => 'client_1'),
      5 => array('name' => 'Client 2', 'id' => 'client_2'),
    ),

    // The links are the paths between the nodes. You can define each link as an
    // associative PHP array (which will get turned into a JS object). The D3,
    // d3-plugins-sankey, d3.chart, and d3.chart.sankey source code does not
    // explicitly specify what keys are valid in link objects, but the following
    // keys are known to work:
    // - source (required): The array index of the node to connect from.
    // - target (required): The array index of the node to connect to.
    // - value (optional): A number representing how big the link is. If you do
    //   not specify a value, the actual size of the link will depend on how
    //   many other links are connected to the source and target nodes. You can
    //   specify any number (integer, float; positive or negative): the Sankey
    //   charting library will assume that the value of all links are all in the
    //   same unit (e.g.: dollars, percentage points, etc.).
    //
    // The order of the links do not matter. I have visually grouped the links
    // with blank lines to illustrate each path from one side of the Sankey
    // diagram to the other.
    'links' => array(
      array('value' => 10000, 'source' => 0, 'target' => 1),
      array('value' => 7000, 'source' => 1, 'target' => 4),
      array('value' => 3000, 'source' => 1, 'target' => 5),

      array('value' => 15000, 'source' => 0, 'target' => 2),
      array('value' => 7500, 'source' => 2, 'target' => 4),
      array('value' => 7500, 'source' => 2, 'target' => 5),

      array('value' => 8000, 'source' => 0, 'target' => 3),
      array('value' => 4000, 'source' => 3, 'target' => 4),
      array('value' => 4000, 'source' => 3, 'target' => 5),
    ),
  );

  return d3_draw($chart);
}