'use strict'

const WebViewImpl = require('./web-view');
//const guestViewInternal = require('./guest-view-internal');
const webViewConstants = require('./web-view-constants');
//const remote = require('electron').remote;

// Helper function to resolve url set in attribute.
var a = document.createElement('a');

var resolveURL = function (url) {
    a.href = url;
    return a.href;
}

// Attribute objects.
// Default implementation of a WebView attribute.
class WebViewAttribute {
    constructor(name, webViewImpl) {
        this.name = name;
        this.value = webViewImpl.webviewNode[name] || '';
        this.webViewImpl = webViewImpl;
        this.ignoreMutation = false;
        this.defineProperty();
    }

    // Retrieves and returns the attribute's value.
    getValue() {
        return this.webViewImpl.webviewNode.getAttribute(this.name) || this.value;
    }

    // Sets the attribute's value.
    setValue(value) {
        return this.webViewImpl.webviewNode.setAttribute(this.name, value || '');
    }

    // Changes the attribute's value without triggering its mutation handler.
    setValueIgnoreMutation(value) {
        this.ignoreMutation = true;
        this.setValue(value);
        this.ignoreMutation = false;
    }

    // Defines this attribute as a property on the webview node.
    defineProperty() {
        return Object.defineProperty(this.webViewImpl.webviewNode, this.name, {
    get: () => {
        return this.getValue();
    },
    set: (value) => {
        return this.setValue(value);
    },
            enumerable: true
        });
    }

    // Called when the attribute's value changes.
    handleMutation() { }
}

// An attribute that is treated as a Boolean.
class BooleanAttribute extends WebViewAttribute {
    getValue() {
        return this.webViewImpl.webviewNode.hasAttribute(this.name)
    }

    setValue(value) {
        if (!value) {
            return this.webViewImpl.webviewNode.removeAttribute(this.name)
        } else {
            return this.webViewImpl.webviewNode.setAttribute(this.name, '')
        }
    }
}

// Attribute used to define the demension limits of autosizing.
class AutosizeDimensionAttribute extends WebViewAttribute {
    getValue() {
        return parseInt(this.webViewImpl.webviewNode.getAttribute(this.name)) || 0;
    }

    handleMutation() {
        console.log("AutosizeDimensionAttribute __callstack__");
//         if (!this.webViewImpl.guestInstanceId) {
//             return;
//         }
//         return guestViewInternal.setSize(this.webViewImpl.guestInstanceId, {
//             enableAutoSize: this.webViewImpl.attributes[webViewConstants.ATTRIBUTE_AUTOSIZE].getValue(),
//            min: {
//                 width: parseInt(this.webViewImpl.attributes[webViewConstants.ATTRIBUTE_MINWIDTH].getValue() || 0),
//                 height: parseInt(this.webViewImpl.attributes[webViewConstants.ATTRIBUTE_MINHEIGHT].getValue() || 0)
//             },
//            max: {
//                 width: parseInt(this.webViewImpl.attributes[webViewConstants.ATTRIBUTE_MAXWIDTH].getValue() || 0),
//                 height: parseInt(this.webViewImpl.attributes[webViewConstants.ATTRIBUTE_MAXHEIGHT].getValue() || 0)
//             }
//         });
    }
}

// Attribute that specifies whether the webview should be autosized.
class AutosizeAttribute extends BooleanAttribute {
    constructor(webViewImpl) {
        super(webViewConstants.ATTRIBUTE_AUTOSIZE, webViewImpl);
    }
}

AutosizeAttribute.prototype.handleMutation = AutosizeDimensionAttribute.prototype.handleMutation

// Attribute representing the state of the storage partition.
class PartitionAttribute extends WebViewAttribute {
    constructor(webViewImpl) {
        super(webViewConstants.ATTRIBUTE_PARTITION, webViewImpl);
        this.validPartitionId = true;
    }

    handleMutation(oldValue, newValue) {
        newValue = newValue || '';

        // The partition cannot change if the webview has already navigated.
        if (!this.webViewImpl.beforeFirstNavigation) {
            window.console.error(webViewConstants.ERROR_MSG_ALREADY_NAVIGATED);
            this.setValueIgnoreMutation(oldValue);
            return;
        }
        if (newValue === 'persist:') {
            this.validPartitionId = false;
            return window.console.error(webViewConstants.ERROR_MSG_INVALID_PARTITION_ATTRIBUTE);
        }
    }
}

// Attribute that handles the location and navigation of the webview.
class SrcAttribute extends WebViewAttribute {
    constructor(webViewImpl) {
        super(webViewConstants.ATTRIBUTE_SRC, webViewImpl);
        this.setupMutationObserver();
    }

    getValue() {
        if (this.webViewImpl.webviewNode.hasAttribute(this.name)) {
            return resolveURL(this.webViewImpl.webviewNode.getAttribute(this.name));
        } else {
            return this.value;
        }
    }

    setValueIgnoreMutation(value) {
        super.setValueIgnoreMutation(value);

        // takeRecords() is needed to clear queued up src mutations. Without it, it
        // is possible for this change to get picked up asyncronously by src's
        // mutation observer |observer|, and then get handled even though we do not
        // want to handle this mutation.
        return this.observer.takeRecords();
    }

    handleMutation(oldValue, newValue) {
        // Once we have navigated, we don't allow clearing the src attribute.
        // Once <webview> enters a navigated state, it cannot return to a
        // placeholder state.
        if (!newValue && oldValue) {
            // src attribute changes normally initiate a navigation. We suppress
            // the next src attribute handler call to avoid reloading the page
            // on every guest-initiated navigation.
            this.setValueIgnoreMutation(oldValue);
            return;
        }
        return this.parse();
    }

    // The purpose of this mutation observer is to catch assignment to the src
    // attribute without any changes to its value. This is useful in the case
    // where the webview guest has crashed and navigating to the same address
    // spawns off a new process.
    setupMutationObserver() {
        var params;
        this.observer = new MutationObserver((mutations) => {
            var i, len, mutation, newValue, oldValue;
            for (i = 0, len = mutations.length; i < len; i++) {
                mutation = mutations[i];
                oldValue = mutation.oldValue;
                newValue = this.getValue();
                if (oldValue !== newValue) {
                    return;
                }
                this.handleMutation(oldValue, newValue);
            }
        })
        params = {
            attributes: true,
            attributeOldValue: true,
            attributeFilter: [this.name]
        };
        return this.observer.observe(this.webViewImpl.webviewNode, params);
    }

    parse() {
        var guestContents, httpreferrer, opts, useragent;
        if (!this.webViewImpl.elementAttached || !this.webViewImpl.attributes[webViewConstants.ATTRIBUTE_PARTITION].validPartitionId || !this.getValue()) {
            return;
        }
        if (this.webViewImpl.guestInstanceId == null) {
            if (this.webViewImpl.beforeFirstNavigation) {
                this.webViewImpl.beforeFirstNavigation = false;
                this.webViewImpl.createGuest();
            }
            return;
        }

        // Navigate to |this.src|.
        opts = {};
        httpreferrer = this.webViewImpl.attributes[webViewConstants.ATTRIBUTE_HTTPREFERRER].getValue();
        if (httpreferrer) {
            opts.httpReferrer = httpreferrer;
        }
        useragent = this.webViewImpl.attributes[webViewConstants.ATTRIBUTE_USERAGENT].getValue();
        if (useragent) {
            opts.userAgent = useragent;
        }
        guestContents = remote.getGuestWebContents(this.webViewImpl.guestInstanceId);
        return guestContents.loadURL(this.getValue(), opts);
    }
}

// Attribute specifies HTTP referrer.
class HttpReferrerAttribute extends WebViewAttribute {
    constructor(webViewImpl) {
        super(webViewConstants.ATTRIBUTE_HTTPREFERRER, webViewImpl);
    }
}

// Attribute specifies user agent
class UserAgentAttribute extends WebViewAttribute {
    constructor(webViewImpl) {
        super(webViewConstants.ATTRIBUTE_USERAGENT, webViewImpl);
    }
}

// Attribute that set preload script.
class PreloadAttribute extends WebViewAttribute {
    constructor(webViewImpl) {
        super(webViewConstants.ATTRIBUTE_PRELOAD, webViewImpl);
    }

    getValue() {
        var preload, protocol
        if (!this.webViewImpl.webviewNode.hasAttribute(this.name)) {
            return this.value;
        }
        preload = resolveURL(this.webViewImpl.webviewNode.getAttribute(this.name));
        protocol = preload.substr(0, 5);
        if (protocol !== 'file:') {
            console.error(webViewConstants.ERROR_MSG_INVALID_PRELOAD_ATTRIBUTE);
            preload = '';
        }
        return preload;
    }
}

// Attribute that specifies the blink features to be enabled.
class BlinkFeaturesAttribute extends WebViewAttribute {
    constructor(webViewImpl) {
        super(webViewConstants.ATTRIBUTE_BLINKFEATURES, webViewImpl);
    }
}

// Attribute that specifies the blink features to be disabled.
class DisableBlinkFeaturesAttribute extends WebViewAttribute {
    constructor(webViewImpl) {
        super(webViewConstants.ATTRIBUTE_DISABLEBLINKFEATURES, webViewImpl);
    }
}

// Sets up all of the webview attributes.
WebViewImpl.prototype.setupWebViewAttributes = function () {
    this.attributes = {};
    this.attributes[webViewConstants.ATTRIBUTE_AUTOSIZE] = new AutosizeAttribute(this);
    this.attributes[webViewConstants.ATTRIBUTE_PARTITION] = new PartitionAttribute(this);
    this.attributes[webViewConstants.ATTRIBUTE_SRC] = new SrcAttribute(this);
    this.attributes[webViewConstants.ATTRIBUTE_HTTPREFERRER] = new HttpReferrerAttribute(this);
    this.attributes[webViewConstants.ATTRIBUTE_USERAGENT] = new UserAgentAttribute(this);
    this.attributes[webViewConstants.ATTRIBUTE_NODEINTEGRATION] = new BooleanAttribute(webViewConstants.ATTRIBUTE_NODEINTEGRATION, this);
    this.attributes[webViewConstants.ATTRIBUTE_PLUGINS] = new BooleanAttribute(webViewConstants.ATTRIBUTE_PLUGINS, this);
    this.attributes[webViewConstants.ATTRIBUTE_DISABLEWEBSECURITY] = new BooleanAttribute(webViewConstants.ATTRIBUTE_DISABLEWEBSECURITY, this);
    this.attributes[webViewConstants.ATTRIBUTE_ALLOWPOPUPS] = new BooleanAttribute(webViewConstants.ATTRIBUTE_ALLOWPOPUPS, this);
    this.attributes[webViewConstants.ATTRIBUTE_PRELOAD] = new PreloadAttribute(this);
    this.attributes[webViewConstants.ATTRIBUTE_BLINKFEATURES] = new BlinkFeaturesAttribute(this);
    this.attributes[webViewConstants.ATTRIBUTE_DISABLEBLINKFEATURES] = new DisableBlinkFeaturesAttribute(this);

    const autosizeAttributes = [webViewConstants.ATTRIBUTE_MAXHEIGHT, webViewConstants.ATTRIBUTE_MAXWIDTH, webViewConstants.ATTRIBUTE_MINHEIGHT, webViewConstants.ATTRIBUTE_MINWIDTH];
    autosizeAttributes.forEach((attribute) => {
        this.attributes[attribute] = new AutosizeDimensionAttribute(attribute, this);
    })
}
