const Backbone = require('backbone');
const KeyHandler = require('../../comp/key-handler');
const Keys = require('../../const/keys');
const Format = require('../../util/format');
const Locale = require('../../util/locale');
const Alerts = require('../../comp/alerts');
const FieldViewReadOnly = require('../fields/field-view-read-only');
const FieldViewReadOnlyRaw = require('../fields/field-view-read-only-raw');
const Copyable = require('../../mixins/copyable');

const DetailsHistoryView = Backbone.View.extend({
    template: require('templates/details/details-history.hbs'),

    events: {
        'click .details__history-close': 'closeHistory',
        'click .details__history-timeline-item': 'timelineItemClick',
        'click .details__history-arrow-prev': 'timelinePrevClick',
        'click .details__history-arrow-next': 'timelineNextClick',
        'click .details__history-button-revert': 'revertClick',
        'click .details__history-button-delete': 'deleteClick',
        'click .details__history-button-discard': 'discardClick'
    },

    formats: [
        {
            name: 'ms',
            round: 1,
            format: function(d) {
                return Format.dtStr(d);
            }
        },
        {
            name: 'sec',
            round: 1000,
            format: function(d) {
                return Format.dtStr(d);
            }
        },
        {
            name: 'min',
            round: 1000 * 60,
            format: function(d) {
                return Format.dtStr(d).replace(':00 ', ' ');
            }
        },
        {
            name: 'hour',
            round: 1000 * 60 * 60,
            format: function(d) {
                return Format.dtStr(d).replace(':00', '');
            }
        },
        {
            name: 'day',
            round: 1000 * 60 * 60 * 24,
            format: function(d) {
                return Format.dStr(d);
            }
        },
        {
            name: 'month',
            round: 1000 * 60 * 60 * 24 * 31,
            format: function(d) {
                return Format.dStr(d);
            }
        },
        {
            name: 'year',
            round: 1000 * 60 * 60 * 24 * 365,
            format: function(d) {
                return d.getFullYear();
            }
        }
    ],

    fieldViews: null,

    initialize: function() {
        this.fieldViews = [];
    },

    render: function(visibleRecord) {
        this.renderTemplate(null, true);
        KeyHandler.onKey(Keys.DOM_VK_ESCAPE, this.closeHistory, this);
        this.history = this.model.getHistory();
        this.buildTimeline();
        this.timelineEl = this.$el.find('.details__history-timeline');
        this.bodyEl = this.$el.find('.details__history-body');
        this.timeline.forEach(function(item, ix) {
            $('<i/>')
                .addClass('fa fa-circle details__history-timeline-item')
                .css('left', item.pos * 100 + '%')
                .attr('data-id', ix)
                .appendTo(this.timelineEl);
        }, this);
        this.labels.forEach(function(label) {
            $('<div/>')
                .addClass('details__history-timeline-label')
                .css('left', label.pos * 100 + '%')
                .text(label.text)
                .appendTo(this.timelineEl);
        }, this);
        if (visibleRecord === undefined) {
            visibleRecord = this.history.length - 1;
        }
        this.showRecord(visibleRecord);
        return this;
    },

    remove: function() {
        this.removeFieldViews();
        KeyHandler.offKey(Keys.DOM_VK_ESCAPE, this.closeHistory, this);
        Backbone.View.prototype.remove.call(this);
    },

    removeFieldViews: function() {
        this.fieldViews.forEach(fieldView => fieldView.remove());
        this.fieldViews = [];
    },

    showRecord: function(ix) {
        this.activeIx = ix;
        this.record = this.timeline[ix].rec;
        this.timelineEl.find('.details__history-timeline-item').removeClass('details__history-timeline-item--active');
        this.timelineEl
            .find('.details__history-timeline-item[data-id="' + ix + '"]')
            .addClass('details__history-timeline-item--active');
        this.removeFieldViews();
        this.bodyEl.html('');
        const colorCls = this.record.color ? this.record.color + '-color' : '';
        this.fieldViews.push(
            new FieldViewReadOnly({ model: { name: 'Rev', title: Locale.detHistoryVersion, value: ix + 1 } })
        );
        this.fieldViews.push(
            new FieldViewReadOnly({
                model: {
                    name: 'Updated',
                    title: Locale.detHistorySaved,
                    value:
                        Format.dtStr(this.record.updated) +
                        (this.record.unsaved ? ' (' + Locale.detHistoryCurUnsavedState + ')' : '') +
                        (ix === this.history.length - 1 && !this.record.unsaved
                            ? ' (' + Locale.detHistoryCurState + ')'
                            : '')
                }
            })
        );
        this.fieldViews.push(
            new FieldViewReadOnlyRaw({
                model: {
                    name: '$Title',
                    title: Format.capFirst(Locale.title),
                    value:
                        '<i class="fa fa-' +
                            this.record.icon +
                            ' ' +
                            colorCls +
                            '"></i> ' +
                            _.escape(this.record.title) || '(' + Locale.detHistoryNoTitle + ')'
                }
            })
        );
        this.fieldViews.push(
            new FieldViewReadOnly({
                model: { name: '$UserName', title: Format.capFirst(Locale.user), value: this.record.user }
            })
        );
        this.fieldViews.push(
            new FieldViewReadOnly({
                model: { name: '$Password', title: Format.capFirst(Locale.password), value: this.record.password }
            })
        );
        this.fieldViews.push(
            new FieldViewReadOnly({
                model: { name: '$URL', title: Format.capFirst(Locale.website), value: this.record.url }
            })
        );
        this.fieldViews.push(
            new FieldViewReadOnly({
                model: { name: '$Notes', title: Format.capFirst(Locale.notes), value: this.record.notes }
            })
        );
        this.fieldViews.push(
            new FieldViewReadOnly({
                model: { name: 'Tags', title: Format.capFirst(Locale.tags), value: this.record.tags.join(', ') }
            })
        );
        this.fieldViews.push(
            new FieldViewReadOnly({
                model: {
                    name: 'Expires',
                    title: Locale.detExpires,
                    value: this.record.expires ? Format.dtStr(this.record.expires) : ''
                }
            })
        );
        _.forEach(
            this.record.fields,
            function(value, field) {
                this.fieldViews.push(
                    new FieldViewReadOnly({ model: { name: '$' + field, title: field, value: value } })
                );
            },
            this
        );
        if (this.record.attachments.length) {
            this.fieldViews.push(
                new FieldViewReadOnly({
                    model: {
                        name: 'Attachments',
                        title: Locale.detAttachments,
                        value: this.record.attachments.map(att => att.title).join(', ')
                    }
                })
            );
        }
        this.fieldViews.forEach(function(fieldView) {
            fieldView.setElement(this.bodyEl).render();
            fieldView.on('copy', this.fieldCopied.bind(this));
        }, this);
        const buttons = this.$el.find('.details__history-buttons');
        buttons.find('.details__history-button-revert').toggle(ix < this.history.length - 1);
        buttons.find('.details__history-button-delete').toggle(ix < this.history.length - 1);
        buttons
            .find('.details__history-button-discard')
            .toggle((this.record.unsaved && ix === this.history.length - 1 && this.history.length > 1) || false);
    },

    timelineItemClick: function(e) {
        const id = $(e.target)
            .closest('.details__history-timeline-item')
            .data('id');
        this.showRecord(id);
    },

    timelinePrevClick: function() {
        if (this.activeIx > 0) {
            this.showRecord(this.activeIx - 1);
        }
    },

    timelineNextClick: function() {
        if (this.activeIx < this.timeline.length - 1) {
            this.showRecord(this.activeIx + 1);
        }
    },

    buildTimeline: function() {
        const firstRec = this.history[0];
        const lastRec = this.history[this.history.length - 1];
        this.timeline = this.history.map(rec => ({
            pos: (rec.updated - firstRec.updated) / (lastRec.updated - firstRec.updated),
            rec: rec
        }));
        const period = lastRec.updated - firstRec.updated;
        const format = this.getDateFormat(period);
        this.labels = this.getLabels(firstRec.updated.getTime(), lastRec.updated.getTime(), format.round).map(
            label => ({
                pos: (label - firstRec.updated) / (lastRec.updated - firstRec.updated),
                val: label,
                text: format.format(new Date(label))
            })
        );
    },

    getDateFormat: function(period) {
        for (let i = 0; i < this.formats.length; i++) {
            if (period < this.formats[i].round * 1.2) {
                return this.formats[i > 0 ? i - 1 : 0];
            }
        }
        return this.formats[this.formats.length - 1];
    },

    getLabels: function(first, last, round) {
        const count = Math.floor((last - first) / round);
        if (count > 2) {
            round *= Math.ceil(count / 2);
        }
        const labels = [];
        let label = Math.ceil(first / round) * round;
        while (label < last) {
            labels.push(label);
            label += round;
        }
        if (labels.length > 1 && (labels[0] - first) / (last - first) < 0.1) {
            labels.shift();
        }
        return labels;
    },

    closeHistory: function(updated) {
        this.trigger('close', { updated: updated });
    },

    revertClick: function() {
        Alerts.yesno({
            header: Locale.detHistoryRevertAlert,
            body: Locale.detHistoryRevertAlertBody,
            success: () => {
                this.model.revertToHistoryState(this.record.entry);
                this.closeHistory(true);
            }
        });
    },

    deleteClick: function() {
        Alerts.yesno({
            header: Locale.detHistoryDeleteAlert,
            body: Locale.detHistoryDeleteAlertBody,
            success: () => {
                this.model.deleteHistory(this.record.entry);
                this.render(this.activeIx);
            }
        });
    },

    discardClick: function() {
        Alerts.yesno({
            header: Locale.detHistoryDiscardChangesAlert,
            body: Locale.detHistoryDiscardChangesAlertBody,
            success: () => {
                this.model.discardUnsaved();
                this.closeHistory(true);
            }
        });
    }
});

_.extend(DetailsHistoryView.prototype, Copyable);

module.exports = DetailsHistoryView;