import _debounce from 'lodash-es/debounce';

import {
    descending as d3_descending,
    ascending as d3_ascending
} from 'd3-array';

import {
    event as d3_event,
    select as d3_select
} from 'd3-selection';

import { d3keybinding as d3_keybinding } from '../lib/d3.keybinding.js';

import { t, textDirection } from '../util/locale';
import { svgIcon } from '../svg';
import { uiBackgroundOffset } from './background_offset';
import { uiCmd } from './cmd';
import { uiDisclosure } from './disclosure';
import { uiMapInMap } from './map_in_map';
import { uiTooltipHtml } from './tooltipHtml';
import { utilDetect } from '../util/detect';
import { utilSetTransform, utilCallWhenIdle } from '../util';
import { tooltip } from '../util/tooltip';


export function uiBackground(context) {
    var key = t('background.key');
    var detected = utilDetect();
    var opacities = [1, 0.75, 0.5, 0.25];

    var _opacityDefault = (context.storage('background-opacity') !== null) ?
            (+context.storage('background-opacity')) : 1.0;
    var _customSource = context.background().findSource('custom');
    var _previousBackground;
    var _shown = false;

    var _backgroundList = d3_select(null);
    var _overlayList = d3_select(null);
    var _displayOptions = d3_select(null);
    var _offsetContainer = d3_select(null);

    var backgroundOffset = uiBackgroundOffset(context);


    // Can be 0 from <1.3.0 use or due to issue #1923.
    if (_opacityDefault === 0) _opacityDefault = 1.0;


    function setOpacity(d) {
        var bg = context.container().selectAll('.layer-background')
            .transition()
            .style('opacity', d)
            .attr('data-opacity', d);

        if (!detected.opera) {
            utilSetTransform(bg, 0, 0);
        }

        _displayOptions.selectAll('opacity-options li')
            .classed('active', function(_) { return _ === d; });

        context.storage('background-opacity', d);
    }


    function setTooltips(selection) {
        selection.each(function(d, i, nodes) {
            var item = d3_select(this).select('label'),
                span = item.select('span'),
                placement = (i < nodes.length / 2) ? 'bottom' : 'top',
                description = d.description(),
                isOverflowing = (span.property('clientWidth') !== span.property('scrollWidth'));

            if (d === _previousBackground) {
                item.call(tooltip()
                    .placement(placement)
                    .html(true)
                    .title(function() {
                        var tip = '<div>' + t('background.switch') + '</div>';
                        return uiTooltipHtml(tip, uiCmd('⌘' + key));
                    })
                );
            } else if (description || isOverflowing) {
                item.call(tooltip()
                    .placement(placement)
                    .title(description || d.name())
                );
            } else {
                item.call(tooltip().destroy);
            }
        });
    }


    function updateLayerSelections(selection) {
        function active(d) {
            return context.background().showsLayer(d);
        }

        selection.selectAll('.layer')
            .classed('active', active)
            .classed('switch', function(d) { return d === _previousBackground; })
            .call(setTooltips)
            .selectAll('input')
            .property('checked', active);
    }


    function chooseBackground(d) {
        if (d.id === 'custom' && !d.template()) {
            return editCustom();
        }

        d3_event.preventDefault();
        _previousBackground = context.background().baseLayerSource();
        context.background().baseLayerSource(d);
        _backgroundList.call(updateLayerSelections);
        document.activeElement.blur();
    }


    function editCustom() {
        d3_event.preventDefault();
        var example = 'https://{switch:a,b,c}.tile.openstreetmap.org/{zoom}/{x}/{y}.png';
        var template = window.prompt(
            t('background.custom_prompt', { example: example }),
            _customSource.template() || example
        );

        if (template) {
            context.storage('background-custom-template', template);
            _customSource.template(template);
            chooseBackground(_customSource);
        } else {
            _backgroundList.call(updateLayerSelections);
        }
    }


    function chooseOverlay(d) {
        d3_event.preventDefault();
        context.background().toggleOverlayLayer(d);
        _overlayList.call(updateLayerSelections);
        document.activeElement.blur();
    }


    function drawListItems(layerList, type, change, filter) {
        var sources = context.background()
            .sources(context.map().extent())
            .filter(filter);

        var layerLinks = layerList.selectAll('li.layer')
            .data(sources, function(d) { return d.name(); });

        layerLinks.exit()
            .remove();

        var enter = layerLinks.enter()
            .append('li')
            .attr('class', 'layer')
            .classed('layer-custom', function(d) { return d.id === 'custom'; })
            .classed('best', function(d) { return d.best(); });

        enter.filter(function(d) { return d.id === 'custom'; })
            .append('button')
            .attr('class', 'layer-browse')
            .call(tooltip()
                .title(t('background.custom_button'))
                .placement((textDirection === 'rtl') ? 'right' : 'left')
            )
            .on('click', editCustom)
            .call(svgIcon('#icon-search'));

        enter.filter(function(d) { return d.best(); })
            .append('div')
            .attr('class', 'best')
            .call(tooltip()
                .title(t('background.best_imagery'))
                .placement((textDirection === 'rtl') ? 'right' : 'left')
            )
            .append('span')
            .html('&#9733;');

        var label = enter
            .append('label');

        label
            .append('input')
            .attr('type', type)
            .attr('name', 'layers')
            .on('change', change);

        label
            .append('span')
            .text(function(d) { return d.name(); });


        layerList.selectAll('li.layer')
            .sort(sortSources)
            .style('display', layerList.selectAll('li.layer').data().length > 0 ? 'block' : 'none');

        layerList
            .call(updateLayerSelections);


        function sortSources(a, b) {
            return a.best() && !b.best() ? -1
                : b.best() && !a.best() ? 1
                : d3_descending(a.area(), b.area()) || d3_ascending(a.name(), b.name()) || 0;
        }
    }


    function renderBackgroundList(selection) {
        var container = selection.selectAll('layer-background-list')
            .data([0]);

        _backgroundList = container.enter()
            .append('ul')
            .attr('class', 'layer-list layer-background-list')
            .attr('dir', 'auto')
            .merge(container);
    }


    function renderOverlayList(selection) {
        var container = selection.selectAll('layer-overlay-list')
            .data([0]);

        _overlayList = container.enter()
            .append('ul')
            .attr('class', 'layer-list layer-overlay-list')
            .attr('dir', 'auto')
            .merge(container);
    }


    function renderDisplayOptions(selection) {
        var container = selection.selectAll('display-options-container')
            .data([0]);

        var containerEnter = container.enter()
            .append('div')
            .attr('class', 'display-options-container controls-list');

        /* add opacity switcher */
        var opacityDivEnter = containerEnter
            .append('div')
            .attr('class', 'opacity-options-wrapper');

        opacityDivEnter
            .append('h5')
            .text(t('background.brightness'));

        var opacityUlEnter = opacityDivEnter.append('ul')
            .attr('class', 'opacity-options');

        opacityUlEnter.selectAll('div.opacity')
            .data(opacities)
            .enter()
            .append('li')
            .attr('data-original-title', function(d) {
                return t('background.percent_brightness', { opacity: (d * 100) });
            })
            .on('click.set-opacity', setOpacity)
            .html('<div class="select-box"></div>')
            .call(tooltip()
                .placement((textDirection === 'rtl') ? 'right' : 'left')
            )
            .append('div')
            .attr('class', 'opacity')
            .style('opacity', function(d) { return 1.25 - d; });


        /* add minimap toggle */
        var minimapEnter = containerEnter
            .append('div')
            .attr('class', 'minimap-toggle-wrap');

        var minimapLabelEnter = minimapEnter
            .append('label')
            .call(tooltip()
                .html(true)
                .title(uiTooltipHtml(t('background.minimap.tooltip'), t('background.minimap.key')))
                .placement('top')
            );

        minimapLabelEnter
            .classed('minimap-toggle', true)
            .append('input')
            .attr('type', 'checkbox')
            .on('change', function() {
                uiMapInMap.toggle();
                d3_event.preventDefault();
            });

        minimapLabelEnter
            .append('span')
            .text(t('background.minimap.description'));

        _displayOptions = containerEnter
            .merge(container);
    }


    function update() {
        _backgroundList
            .call(drawListItems, 'radio', chooseBackground, function(d) { return !d.isHidden() && !d.overlay; });

        _overlayList
            .call(drawListItems, 'checkbox', chooseOverlay, function(d) { return !d.isHidden() && d.overlay; });

        _offsetContainer
            .call(backgroundOffset);
    }


    function quickSwitch() {
        if (d3_event) {
            d3_event.stopImmediatePropagation();
            d3_event.preventDefault();
        }
        if (_previousBackground) {
            chooseBackground(_previousBackground);
        }
    }


    function background(selection) {

        function hidePane() {
            setVisible(false);
        }

        function togglePane() {
            if (d3_event) d3_event.preventDefault();
            paneTooltip.hide(button);
            setVisible(!button.classed('active'));
        }

        function setVisible(show) {
            if (show !== _shown) {
                button.classed('active', show);
                _shown = show;

                if (show) {
                    selection
                        .on('mousedown.background-inside', function() {
                            d3_event.stopPropagation();
                        });

                    pane
                        .style('display', 'block')
                        .style('right', '-300px')
                        .transition()
                        .duration(200)
                        .style('right', '0px');

                    pane.selectAll('.layer')
                        .call(setTooltips);

                } else {
                    pane
                        .style('display', 'block')
                        .style('right', '0px')
                        .transition()
                        .duration(200)
                        .style('right', '-300px')
                        .on('end', function() {
                            d3_select(this).style('display', 'none');
                        });

                    selection
                        .on('mousedown.background-inside', null);
                }
            }
        }


        var pane = selection
            .append('div')
            .attr('class', 'fillL map-overlay col3 content hide');

        var paneTooltip = tooltip()
            .placement((textDirection === 'rtl') ? 'right' : 'left')
            .html(true)
            .title(uiTooltipHtml(t('background.description'), key));

        var button = selection
            .append('button')
            .attr('tabindex', -1)
            .on('click', togglePane)
            .call(svgIcon('#icon-layers', 'light'))
            .call(paneTooltip);

        pane
            .append('h2')
            .text(t('background.title'));

        // background list
        pane
            .append('div')
            .attr('class', 'background-background-list-container')
            .call(uiDisclosure(context, 'background_list', true)
                .title(t('background.backgrounds'))
                .content(renderBackgroundList)
            );

        // _backgroundList = pane
        //     .append('ul')
        //     .attr('class', 'layer-list')
        //     .attr('dir', 'auto');

            // "Where does this imagery come from?"
        // pane
        //     .append('div')
        //     .attr('class', 'imagery-faq')
        //     .append('a')
        //     .attr('target', '_blank')
        //     .attr('tabindex', -1)
        //     .call(svgIcon('#icon-out-link', 'inline'))
        //     .attr('href', 'https://github.com/openstreetmap/iD/blob/master/FAQ.md#how-can-i-report-an-issue-with-background-imagery')
        //     .append('span')
        //     .text(t('background.imagery_source_faq'));


        // overlay list
        pane
            .append('div')
            .attr('class', 'background-overlay-list-container')
            .call(uiDisclosure(context, 'overlay_list', true)
                .title(t('background.overlays'))
                .content(renderOverlayList)
            );

        // display settings
        pane
            .append('div')
            .attr('class', 'background-display-options-container')
            .call(uiDisclosure(context, 'background_display_options', true)
                .title(t('background.display_options'))
                .content(renderDisplayOptions)
            );

        // offset controls
        _offsetContainer = pane
            .append('div')
            .attr('class', 'background-offset');


        // add listeners
        context.map()
            .on('move.background-update', _debounce(utilCallWhenIdle(update), 1000));

        context.background()
            .on('change.background-update', update);


        update();
        setOpacity(_opacityDefault);

        var keybinding = d3_keybinding('background')
            .on(key, togglePane)
            .on(uiCmd('⌘' + key), quickSwitch)
            .on([t('map_data.key'), t('help.key')], hidePane);

        d3_select(document)
            .call(keybinding);
    }

    return background;
}