// Finds all fieldsets with class="collapse", collapses them, and gives each

// one a "Show" link that uncollapses it. The "Show" link becomes a "Hide"

// link when the fieldset is visible.

function findForm(node) {

    // returns the node of the form containing the given node

    if (node.tagName.toLowerCase() != 'form') {

        return findForm(node.parentNode);

    }

    return node;

}

var CollapsedFieldsets = {

    collapse_re: /\bcollapse\b/,   // Class of fieldsets that should be dealt with.

    collapsed_re: /\bcollapsed\b/, // Class that fieldsets get when they're hidden.

    collapsed_class: 'collapsed',

    init: function() {

        var fieldsets = document.getElementsByTagName('fieldset');

        var collapsed_seen = false;

        for (var i = 0, fs; fs = fieldsets[i]; i++) {

            // Collapse this fieldset if it has the correct class, and if it

            // doesn't have any errors. (Collapsing shouldn't apply in the case

            // of error messages.)

            if (fs.className.match(CollapsedFieldsets.collapse_re) && !CollapsedFieldsets.fieldset_has_errors(fs)) {

                collapsed_seen = true;

                // Give it an additional class, used by CSS to hide it.

                fs.className += ' ' + CollapsedFieldsets.collapsed_class;

                // (<a id="fieldsetcollapser3" class="collapse-toggle" href="#">Show</a>)

                var collapse_link = document.createElement('a');

                collapse_link.className = 'collapse-toggle';

                collapse_link.id = 'fieldsetcollapser' + i;

                collapse_link.onclick = new Function('CollapsedFieldsets.show('+i+'); return false;');

                collapse_link.href = '#';

                collapse_link.innerHTML = gettext('Show');

                var h2 = fs.getElementsByTagName('h2')[0];

                h2.appendChild(document.createTextNode(' ('));

                h2.appendChild(collapse_link);

                h2.appendChild(document.createTextNode(')'));

            }

        }

        if (collapsed_seen) {

            // Expand all collapsed fieldsets when form is submitted.

            addEvent(findForm(document.getElementsByTagName('fieldset')[0]), 'submit', function() { CollapsedFieldsets.uncollapse_all(); });

        }

    },

    fieldset_has_errors: function(fs) {

        // Returns true if any fields in the fieldset have validation errors.

        var divs = fs.getElementsByTagName('div');

        for (var i=0; i<divs.length; i++) {

            if (divs[i].className.match(/\berrors\b/)) {

                return true;

            }

        }

        return false;

    },

    show: function(fieldset_index) {

        var fs = document.getElementsByTagName('fieldset')[fieldset_index];

        // Remove the class name that causes the "display: none".

        fs.className = fs.className.replace(CollapsedFieldsets.collapsed_re, '');

        // Toggle the "Show" link to a "Hide" link

        var collapse_link = document.getElementById('fieldsetcollapser' + fieldset_index);

        collapse_link.onclick = new Function('CollapsedFieldsets.hide('+fieldset_index+'); return false;');

        collapse_link.innerHTML = gettext('Hide');

    },

    hide: function(fieldset_index) {

        var fs = document.getElementsByTagName('fieldset')[fieldset_index];

        // Add the class name that causes the "display: none".

        fs.className += ' ' + CollapsedFieldsets.collapsed_class;

        // Toggle the "Hide" link to a "Show" link

        var collapse_link = document.getElementById('fieldsetcollapser' + fieldset_index);

        collapse_link.onclick = new Function('CollapsedFieldsets.show('+fieldset_index+'); return false;');

        collapse_link.innerHTML = gettext('Show');

    },

    uncollapse_all: function() {

        var fieldsets = document.getElementsByTagName('fieldset');

        for (var i=0; i<fieldsets.length; i++) {

            if (fieldsets[i].className.match(CollapsedFieldsets.collapsed_re)) {

                CollapsedFieldsets.show(i);

            }

        }

    }

}

addEvent(window, 'load', CollapsedFieldsets.init);