/*
 * Copyright 2015 Open Networking Laboratory
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/*
 ONOS GUI -- SVG -- Util Service
 */

/*
 The SVG Util Service provides a miscellany of utility functions.
 */

(function () {
    'use strict';

    // injected references
    var $log, fs;

    angular.module('onosSvg')
        .factory('SvgUtilService', ['$log', 'FnService',
        function (_$log_, _fs_) {
            $log = _$log_;
            fs = _fs_;

            // TODO: change 'force' ref to be 'force.alpha' ref.
            function createDragBehavior(force, selectCb, atDragEnd,
                                        dragEnabled, clickEnabled) {
                var draggedThreshold = d3.scale.linear()
                        .domain([0, 0.1])
                        .range([5, 20])
                        .clamp(true),
                    drag,
                    fSel = fs.isF(selectCb),
                    fEnd = fs.isF(atDragEnd),
                    fDEn = fs.isF(dragEnabled),
                    fCEn = fs.isF(clickEnabled),
                    bad = [];

                function naf(what) {
                    return 'SvgUtilService: createDragBehavior(): ' + what +
                        ' is not a function';
                }

                if (!force) {
                    bad.push('SvgUtilService: createDragBehavior(): ' +
                    'Bad force reference');
                }
                if (!fSel) {
                    bad.push(naf('selectCb'));
                }
                if (!fEnd) {
                    bad.push(naf('atDragEnd'));
                }
                if (!fDEn) {
                    bad.push(naf('dragEnabled'));
                }
                if (!fCEn) {
                    bad.push(naf('clickEnabled'));
                }

                if (bad.length) {
                    $log.error(bad.join('\n'));
                    return null;
                }

                function dragged(d) {
                    var threshold = draggedThreshold(force.alpha()),
                        dx = d.oldX - d.px,
                        dy = d.oldY - d.py;
                    if (Math.abs(dx) >= threshold || Math.abs(dy) >= threshold) {
                        d.dragged = true;
                    }
                    return d.dragged;
                }

                drag = d3.behavior.drag()
                    .origin(function(d) { return d; })
                    .on('dragstart', function(d) {
                        if (clickEnabled() || dragEnabled()) {
                            d3.event.sourceEvent.stopPropagation();

                            d.oldX = d.x;
                            d.oldY = d.y;
                            d.dragged = false;
                            d.fixed |= 2;
                            d.dragStarted = true;
                        }
                    })
                    .on('drag', function(d) {
                        if (dragEnabled()) {
                            d.px = d3.event.x;
                            d.py = d3.event.y;
                            if (dragged(d)) {
                                if (!force.alpha()) {
                                    force.alpha(.025);
                                }
                            }
                        }
                    })
                    .on('dragend', function(d) {
                        if (d.dragStarted) {
                            d.dragStarted = false;
                            if (!dragged(d)) {
                                // consider this the same as a 'click'
                                // (selection of a node)
                                if (clickEnabled()) {
                                    selectCb.call(this, d);
                                }
                            }
                            d.fixed &= ~6;

                            // hook at the end of a drag gesture
                            if (dragEnabled()) {
                                atDragEnd.call(this, d);
                            }
                        }
                    });

                return drag;
            }


            function loadGlow(defs, r, g, b, id) {
                var glow = defs.append('filter')
                    .attr('x', '-50%')
                    .attr('y', '-50%')
                    .attr('width', '200%')
                    .attr('height', '200%')
                    .attr('id', id);

                glow.append('feColorMatrix')
                    .attr('type', 'matrix')
                    .attr('values',
                    '0 0 0 0  ' + r + ' ' +
                    '0 0 0 0  ' + g + ' ' +
                    '0 0 0 0  ' + b + ' ' +
                    '0 0 0 1  0 ');

                glow.append('feGaussianBlur')
                    .attr('stdDeviation', 3)
                    .attr('result', 'coloredBlur');

                glow.append('feMerge').selectAll('feMergeNode')
                    .data(['coloredBlur', 'SourceGraphic'])
                    .enter().append('feMergeNode')
                    .attr('in', String);
            }

            function loadGlowDefs(defs) {
                loadGlow(defs, 0.0, 0.0, 0.7, 'blue-glow');
                loadGlow(defs, 1.0, 1.0, 0.3, 'yellow-glow');
            }

            // --- Ordinal scales for 7 values.

            //               blue       brown      brick red  sea green  purple     dark teal  lime
            var lightNorm = ['#3E5780', '#78533B', '#CB4D28', '#018D61', '#8A2979', '#006D73', '#56AF00'],
                lightMute = ['#A8B8CC', '#CCB3A8', '#FFC2BD', '#96D6BF', '#D19FCE', '#8FCCCA', '#CAEAA4'],

                darkNorm  = ['#304860', '#664631', '#A8391B', '#00754B', '#77206D', '#005959', '#428700'],
                darkMute  = ['#304860', '#664631', '#A8391B', '#00754B', '#77206D', '#005959', '#428700'];

            var colors= {
                light: {
                    norm: d3.scale.ordinal().range(lightNorm),
                    mute: d3.scale.ordinal().range(lightMute)
                },
                dark: {
                    norm: d3.scale.ordinal().range(darkNorm),
                    mute: d3.scale.ordinal().range(darkMute)
                }
            };

            function cat7() {
                var tcid = 'd3utilTestCard';

                function getColor(id, muted, theme) {
                    // NOTE: since we are lazily assigning domain ids, we need to
                    //       get the color from all 4 scales, to keep the domains
                    //       in sync.
                    var ln = colors.light.norm(id),
                        lm = colors.light.mute(id),
                        dn = colors.dark.norm(id),
                        dm = colors.dark.mute(id);
                    if (theme === 'dark') {
                        return muted ? dm : dn;
                    } else {
                        return muted ? lm : ln;
                    }
                }

                function testCard(svg) {
                    var g = svg.select('g#' + tcid),
                        dom = d3.range(7),
                        k, muted, theme, what;

                    if (!g.empty()) {
                        g.remove();

                    } else {
                        g = svg.append('g')
                            .attr('id', tcid)
                            .attr('transform', 'scale(4)translate(20,20)');

                        for (k=0; k<4; k++) {
                            muted = k%2;
                            what = muted ? ' muted' : ' normal';
                            theme = k < 2 ? 'light' : 'dark';
                            dom.forEach(function (id, i) {
                                var x = i * 20,
                                    y = k * 20,
                                    f = get(id, muted, theme);
                                g.append('circle').attr({
                                    cx: x,
                                    cy: y,
                                    r: 5,
                                    fill: f
                                });
                            });
                            g.append('rect').attr({
                                x: 140,
                                y: k * 20 - 5,
                                width: 32,
                                height: 10,
                                rx: 2,
                                fill: '#888'
                            });
                            g.append('text').text(theme + what)
                                .attr({
                                    x: 142,
                                    y: k * 20 + 2,
                                    fill: 'white'
                                })
                                .style('font-size', '4pt');
                        }
                    }
                }

                return {
                    testCard: testCard,
                    getColor: getColor
                };
            }

            function translate(x, y) {
                if (fs.isA(x) && x.length === 2 && !y) {
                    return 'translate(' + x[0] + ',' + x[1] + ')';
                }
                return 'translate(' + x + ',' + y + ')';
            }

            function scale(x, y) {
                return 'scale(' + x + ',' + y + ')';
            }

            function skewX(x) {
                return 'skewX(' + x + ')';
            }

            function rotate(deg) {
                return 'rotate(' + deg + ')';
            }

            function stripPx(s) {
                return s.replace(/px$/,'');
            }

            function safeId(s) {
                return s.replace(/[^a-z0-9]/gi, '-');
            }

            function makeVisible(el, b) {
                el.style('visibility', (b ? 'visible' : 'hidden'));
            }

            function isVisible(el) {
                return el.style('visibility') === 'visible';
            }

            return {
                createDragBehavior: createDragBehavior,
                loadGlowDefs: loadGlowDefs,
                cat7: cat7,
                translate: translate,
                scale: scale,
                skewX: skewX,
                rotate: rotate,
                stripPx: stripPx,
                safeId: safeId,
                visible: function (el, x) {
                            if (x === undefined) {
                                return isVisible(el);
                            } else {
                                makeVisible(el, x);
                            }
                         }
            };
        }]);
}());