/*
This file is part of Ext JS 4.2

Copyright (c) 2011-2013 Sencha Inc

Contact:  http://www.sencha.com/contact

GNU General Public License Usage
This file may be used under the terms of the GNU General Public License version 3.0 as
published by the Free Software Foundation and appearing in the file LICENSE included in the
packaging of this file.

Please review the following information to ensure the GNU General Public License version 3.0
requirements will be met: http://www.gnu.org/copyleft/gpl.html.

If you are unsure which license is appropriate for your use, please contact the sales department
at http://www.sencha.com/contact.

Build date: 2013-05-16 14:36:50 (f9be68accb407158ba2b1be2c226a6ce1f649314)
*/
/**
 * @class Ext.chart.axis.Gauge
 *
 * Gauge Axis is the axis to be used with a Gauge series. The Gauge axis
 * displays numeric data from an interval defined by the `minimum`, `maximum` and
 * `step` configuration properties. The placement of the numeric data can be changed
 * by altering the `margin` option that is set to `10` by default.
 *
 * A possible configuration for this axis would look like:
 *
 *     axes: [{
 *         type: 'gauge',
 *         position: 'gauge',
 *         minimum: 0,
 *         maximum: 100,
 *         steps: 10,
 *         margin: 7
 *     }],
 */
Ext.define('Ext.chart.axis.Gauge', {

    /* Begin Definitions */

    extend: 'Ext.chart.axis.Abstract',

    /* End Definitions */

    /**
     * @cfg {Number} minimum (required)
     * The minimum value of the interval to be displayed in the axis.
     */

    /**
     * @cfg {Number} maximum (required)
     * The maximum value of the interval to be displayed in the axis.
     */

    /**
     * @cfg {Number} steps (required)
     * The number of steps and tick marks to add to the interval.
     */

    /**
     * @cfg {Number} [margin=10]
     * The offset positioning of the tick marks and labels in pixels.
     */

    /**
     * @cfg {String} title
     * The title for the Axis.
     */

    position: 'gauge',

    alias: 'axis.gauge',

    drawAxis: function(init) {
        var chart = this.chart,
            surface = chart.surface,
            bbox = chart.chartBBox,
            centerX = bbox.x + (bbox.width / 2),
            centerY = bbox.y + bbox.height,
            margin = this.margin || 10,
            rho = Math.min(bbox.width, 2 * bbox.height) /2 + margin,
            sprites = [], sprite,
            steps = this.steps,
            i, pi = Math.PI,
            cos = Math.cos,
            sin = Math.sin;

        if (this.sprites && !chart.resizing) {
            this.drawLabel();
            return;
        }

        if (this.margin >= 0) {
            if (!this.sprites) {
                //draw circles
                for (i = 0; i <= steps; i++) {
                    sprite = surface.add({
                        type: 'path',
                        path: ['M', centerX + (rho - margin) * cos(i / steps * pi - pi),
                                    centerY + (rho - margin) * sin(i / steps * pi - pi),
                                    'L', centerX + rho * cos(i / steps * pi - pi),
                                    centerY + rho * sin(i / steps * pi - pi), 'Z'],
                        stroke: '#ccc'
                    });
                    sprite.setAttributes({
                        hidden: false
                    }, true);
                    sprites.push(sprite);
                }
            } else {
                sprites = this.sprites;
                //draw circles
                for (i = 0; i <= steps; i++) {
                    sprites[i].setAttributes({
                        path: ['M', centerX + (rho - margin) * cos(i / steps * pi - pi),
                                    centerY + (rho - margin) * sin(i / steps * pi - pi),
                               'L', centerX + rho * cos(i / steps * pi - pi),
                                    centerY + rho * sin(i / steps * pi - pi), 'Z'],
                        stroke: '#ccc'
                    }, true);
                }
            }
        }
        this.sprites = sprites;
        this.drawLabel();
        if (this.title) {
            this.drawTitle();
        }
    },

    drawTitle: function() {
        var me = this,
            chart = me.chart,
            surface = chart.surface,
            bbox = chart.chartBBox,
            labelSprite = me.titleSprite,
            labelBBox;

        if (!labelSprite) {
            me.titleSprite = labelSprite = surface.add(Ext.apply({
                type: 'text',
                zIndex: 2
            }, me.axisTitleStyle, me.labelTitle));
        }
        labelSprite.setAttributes(Ext.apply({
            text: me.title
        }, me.label || {}), true);
        labelBBox = labelSprite.getBBox();
        labelSprite.setAttributes({
            x: bbox.x + (bbox.width / 2) - (labelBBox.width / 2),
            y: bbox.y + bbox.height - (labelBBox.height / 2) - 4
        }, true);
    },

    /**
     * Updates the {@link #title} of this axis.
     * @param {String} title
     */
    setTitle: function(title) {
        this.title = title;
        this.drawTitle();
    },

    drawLabel: function() {
        var chart = this.chart,
            surface = chart.surface,
            bbox = chart.chartBBox,
            centerX = bbox.x + (bbox.width / 2),
            centerY = bbox.y + bbox.height,
            margin = this.margin || 10,
            rho = Math.min(bbox.width, 2 * bbox.height) /2 + 2 * margin,
            round = Math.round,
            labelArray = [], label,
            maxValue = this.maximum || 0,
            minValue = this.minimum || 0,
            steps = this.steps, i = 0,
            adjY,
            pi = Math.PI,
            cos = Math.cos,
            sin = Math.sin,
            labelConf = this.label,
            renderer = labelConf.renderer || Ext.identityFn;

        if (!this.labelArray) {
            //draw scale
            for (i = 0; i <= steps; i++) {
                // TODO Adjust for height of text / 2 instead
                adjY = (i === 0 || i === steps) ? 7 : 0;
                label = surface.add({
                    type: 'text',
                    text: renderer(round(minValue + i / steps * (maxValue - minValue))),
                    x: centerX + rho * cos(i / steps * pi - pi),
                    y: centerY + rho * sin(i / steps * pi - pi) - adjY,
                    'text-anchor': 'middle',
                    'stroke-width': 0.2,
                    zIndex: 10,
                    stroke: '#333'
                });
                label.setAttributes({
                    hidden: false
                }, true);
                labelArray.push(label);
            }
        }
        else {
            labelArray = this.labelArray;
            //draw values
            for (i = 0; i <= steps; i++) {
                // TODO Adjust for height of text / 2 instead
                adjY = (i === 0 || i === steps) ? 7 : 0;
                labelArray[i].setAttributes({
                    text: renderer(round(minValue + i / steps * (maxValue - minValue))),
                    x: centerX + rho * cos(i / steps * pi - pi),
                    y: centerY + rho * sin(i / steps * pi - pi) - adjY
                }, true);
            }
        }
        this.labelArray = labelArray;
    }
});