const Gio = imports.gi.Gio;
const Gtk = imports.gi.Gtk;
const GObject = imports.gi.GObject;
const Lang = imports.lang;
const WebKit = imports.gi.WebKit2;
const Utils = imports.wikipedia.utils;

const hostName = "http://127.0.0.1:3000/"
const getPageByTitleURI = "getArticleByTitle?";
const getPageByQueryURI = "getTopArticleByQuery?";

// Interpret image:// URIs as wikipedia images
WebKit.WebContext.get_default().register_uri_scheme('image', function(request) {
    let filename = request.get_uri().slice('image://'.length);
    filename = decodeURI(filename);
    let pictures_dir = request.get_web_view()._getArticleImagesPath();
    let parent = Gio.File.new_for_path(pictures_dir);
    let file = parent.get_child(filename);
    try {
        let stream = file.read(null);
        request.finish(stream, -1, 'image/png');
    } catch (err) {
        let stream = new Gio.MemoryInputStream();
        request.finish(stream, 0, 'image/png');
    }
});

const WikipediaWebView = new Lang.Class({
    Name: 'EndlessWikipediaWebView',
    Extends: WebKit.WebView,
    Properties: {
        'hide-links': GObject.ParamSpec.boolean('hide-links',
            'Hide article links',
            'A boolean to determine whether links should be shown',
            GObject.ParamFlags.READWRITE | GObject.ParamFlags.CONSTRUCT,
            false)
    },

    _init: function(params, links_to_show) {
        this.parent(params);
        // For debugging
        //let settings = this.get_settings();
        //settings.set_enable_developer_extras(true);
        //this.set_settings(settings);
        this.connect('context-menu', Lang.bind(this, function(){return true}));

        this._links_to_show = links_to_show;
        this.connect('decide-policy',
            Lang.bind(this, this._onNavigation));
        this.connect('load-changed',
            Lang.bind(this, this._onLoadChange));
    },

    _getFullURL: function(base_url, params){
        let full_url = base_url;
        for(let key in params){
            full_url += key + "=" + params[key] + "&";
        }
        full_url = full_url.slice(0, -1);
        return full_url
    },

    loadArticleByURI: function(uri) {
        let parts = uri.split("/");
        let suffix = parts[parts.length - 1];
        let title = decodeURI(suffix.replace("_", " ", 'g'));
        this.loadArticleByTitle(title);
    },

    loadArticleByTitle: function(title) {
        let params = {"title":title, "hideLinks":this.hide_links};
        let url = this._getFullURL(hostName + getPageByTitleURI, params);
        this.load_uri(url);
    },

    loadArticleBySearchQuery: function(query) {
        let params = {"query":query, "hideLinks":this.hide_links};
        let url = this._getFullURL(hostName + getPageByQueryURI, params);
        this.load_uri(url);
    },

    scriptFinished: function(){
        // NO OP
    },

    setAllowedLinks: function(){
        // If you want to show all links, then
        // no point in showing some subset of them as well
        if(!this.hide_links){
            return;
        }
        let str = JSON.stringify(this._links_to_show);
        let script = "window.links_to_show = " + str;
        this.run_javascript(script, null, this.scriptFinished, null);
    },

    _getArticleImagesPath: function() {
        let cur_exec = this.get_toplevel().get_application().application_base_path;
        return cur_exec + "/web_view/article_images/";
    },

    _onNavigation: function(webview, decision, decision_type) {
        if (decision_type == WebKit.PolicyDecisionType.NAVIGATION_ACTION) {
            let uri = decision.request.uri;
            if (uri.startsWith(hostName + "wiki/")) {
                let parts = uri.split("/");
                let suffix = parts[parts.length - 1];
                let title = decodeURI(suffix.replace("_", " ", 'g'));
                this.loadArticleByTitle(title);
                return true;
            }
        }
        return false; // not handled, default behavior
    },

    _onLoadChange: function(webview, load_event, data){
        this.setAllowedLinks();
    }
});