/*
Copyright 2015, 2016 OpenMarket Ltd

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.
*/

'use strict';

var React = require('react');
var filesize = require('filesize');

var MatrixClientPeg = require('../../../MatrixClientPeg');
var Modal = require('../../../Modal');
var sdk = require('../../../index');
var dis = require("../../../dispatcher");

module.exports = React.createClass({
    displayName: 'MImageBody',

    propTypes: {
        /* the MatrixEvent to show */
        mxEvent: React.PropTypes.object.isRequired,

        /* callback called when images in events are loaded */
        onImageLoad: React.PropTypes.func,
    },

    thumbHeight: function(fullWidth, fullHeight, thumbWidth, thumbHeight) {
        if (!fullWidth || !fullHeight) {
            // Cannot calculate thumbnail height for image: missing w/h in metadata. We can't even
            // log this because it's spammy
            return undefined;
        }
        if (fullWidth < thumbWidth && fullHeight < thumbHeight) {
            // no scaling needs to be applied
            return fullHeight;
        }
        var widthMulti = thumbWidth / fullWidth;
        var heightMulti = thumbHeight / fullHeight;
        if (widthMulti < heightMulti) {
            // width is the dominant dimension so scaling will be fixed on that
            return Math.floor(widthMulti * fullHeight);
        }
        else {
            // height is the dominant dimension so scaling will be fixed on that
            return Math.floor(heightMulti * fullHeight);
        }
    },

    onClick: function onClick(ev) {
        if (ev.button == 0 && !ev.metaKey) {
            ev.preventDefault();
            var content = this.props.mxEvent.getContent();
            var httpUrl = MatrixClientPeg.get().mxcUrlToHttp(content.url);
            var ImageView = sdk.getComponent("elements.ImageView");
            var params = {
                src: httpUrl,
                mxEvent: this.props.mxEvent
            };

            if (content.info) {
                params.width = content.info.w;
                params.height = content.info.h;
            }

            Modal.createDialog(ImageView, params, "mx_Dialog_lightbox");
        }
    },

    _isGif: function() {
        var content = this.props.mxEvent.getContent();
        return (content && content.info && content.info.mimetype === "image/gif");
    },

    onImageEnter: function(e) {
        if (!this._isGif()) {
            return;
        }
        var imgElement = e.target;
        imgElement.src = MatrixClientPeg.get().mxcUrlToHttp(
            this.props.mxEvent.getContent().url
        );
    },

    onImageLeave: function(e) {
        if (!this._isGif()) {
            return;
        }
        var imgElement = e.target;
        imgElement.src = this._getThumbUrl();
    },

    _getThumbUrl: function() {
        var content = this.props.mxEvent.getContent();
        return MatrixClientPeg.get().mxcUrlToHttp(content.url, 800, 600);
    },

    componentDidMount: function() {
        this.dispatcherRef = dis.register(this.onAction);
        this.fixupHeight();
    },

    componentWillUnmount: function() {
        dis.unregister(this.dispatcherRef);
    },

    onAction: function(payload) {
        if (payload.action === "timeline_resize") {
            this.fixupHeight();
        }
    },

    fixupHeight: function() {
        var content = this.props.mxEvent.getContent();

        var thumbHeight = null;
        var timelineWidth = this._body.offsetWidth;
        var maxHeight = 600*timelineWidth/800;

        //console.log("trying to fit image into timelineWidth of " + this._body.offsetWidth + " or " + this._body.clientWidth);
        if (content.info) thumbHeight = this.thumbHeight(content.info.w, content.info.h, timelineWidth, maxHeight);
        this._image.style.height = thumbHeight + "px";
    },

    render: function() {
        var TintableSvg = sdk.getComponent("elements.TintableSvg");
        var content = this.props.mxEvent.getContent();
        var cli = MatrixClientPeg.get();

        var thumbUrl = this._getThumbUrl();
        if (thumbUrl) {
            return (
                <span className="mx_MImageBody" ref={(c) => this._body = c}>
                    <a href={cli.mxcUrlToHttp(content.url)} onClick={ this.onClick }>
                        <img className="mx_MImageBody_thumbnail" src={thumbUrl} ref={(c) => this._image = c}
                            alt={content.body}
                            onMouseEnter={this.onImageEnter}
                            onMouseLeave={this.onImageLeave}
                            onLoad={this.props.onImageLoad} />
                    </a>
                    <div className="mx_MImageBody_download">
                        <a href={cli.mxcUrlToHttp(content.url)} target="_blank">
                            <TintableSvg src="img/download.svg" width="12" height="14"/>
                            Download {content.body} ({ content.info && content.info.size ? filesize(content.info.size) : "Unknown size" })
                        </a>
                    </div>
                </span>
            );
        } else if (content.body) {
            return (
                <span className="mx_MImageBody">
                    Image '{content.body}' cannot be displayed.
                </span>
            );
        } else {
            return (
                <span className="mx_MImageBody">
                    This image cannot be displayed.
                </span>
            );
        }
    },
});