/**
 * Copyright JS Foundation and other contributors, http://js.foundation
 *
 * 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.
 **/

const clone = require("clone");
const Flow = require('./Flow').Flow;
const context = require('../context');
const util = require("util");

const redUtil = require("@node-red/util").util;
const flowUtil = require("./util");


const credentials = require("../credentials");

var Log;

/**
 * Create deep copy of object
 */
function deepCopy(obj) {
    return JSON.parse(JSON.stringify(obj));
}

/**
 * Evaluate Input Value
 */
function evaluateInputValue(value, type, node) {
    if (type === "bool") {
        return (value === "true") || (value === true);
    }
    if (type === "cred") {
        return value;
    }
    return redUtil.evaluateNodeProperty(value, type, node, null, null);
}

/**
 * Compose information object for env var
 */
function composeInfo(info, val) {
    var result = {
        name: info.name,
        type: info.type,
        value: val,
    };
    if (info.ui) {
        var ui = info.ui;
        result.ui = {
            hasUI: ui.hasUI,
            icon: ui.icon,
            labels: ui.labels,
            type: ui.type
        };
        var retUI = result.ui;
        if (ui.type === "input") {
            retUI.inputTypes = ui.inputTypes;
        }
        if (ui.type === "select") {
            retUI.menu = ui.menu;
        }
        if (ui.type === "spinner") {
            retUI.spinner = ui.spinner;
        }
    }
    return result;
}


/**
 * This class represents a subflow - which is handled as a special type of Flow
 */
class Subflow extends Flow {

    /**
     * Create a Subflow object.
     * This takes a subflow definition and instance node, creates a clone of the
     * definition with unique ids applied and passes to the super class.
     * @param {[type]} parent          [description]
     * @param {[type]} globalFlow      [description]
     * @param {[type]} subflowDef      [description]
     * @param {[type]} subflowInstance [description]
     */
    constructor(parent,globalFlow,subflowDef,subflowInstance) {
        // console.log("CREATE SUBFLOW",subflowDef.id,subflowInstance.id,"alias?",subflowInstance._alias);
        // console.log("SubflowInstance\n"+JSON.stringify(subflowInstance," ",2));
        // console.log("SubflowDef\n"+JSON.stringify(subflowDef," ",2));
        var subflows = parent.flow.subflows;
        var globalSubflows = parent.global.subflows;

        var node_map = {};
        var node;
        var wires;
        var i;

        var subflowInternalFlowConfig = {
            id: subflowInstance.id,
            configs: {},
            nodes: {},
            subflows: {}
        }

        if (subflowDef.configs) {
            // Clone all of the subflow config node definitions and give them new IDs
            for (i in subflowDef.configs) {
                if (subflowDef.configs.hasOwnProperty(i)) {
                    node = createNodeInSubflow(subflowInstance.id,subflowDef.configs[i]);
                    node_map[node._alias] = node;
                    subflowInternalFlowConfig.configs[node.id] = node;
                }
            }
        }
        if (subflowDef.nodes) {
            // Clone all of the subflow node definitions and give them new IDs
            for (i in subflowDef.nodes) {
                if (subflowDef.nodes.hasOwnProperty(i)) {
                    node = createNodeInSubflow(subflowInstance.id,subflowDef.nodes[i]);
                    node_map[node._alias] = node;
                    subflowInternalFlowConfig.nodes[node.id] = node;
                }
            }
        }

        subflowInternalFlowConfig.subflows = clone(subflowDef.subflows || {});

        remapSubflowNodes(subflowInternalFlowConfig.configs,node_map);
        remapSubflowNodes(subflowInternalFlowConfig.nodes,node_map);

        // console.log("Instance config\n",JSON.stringify(subflowInternalFlowConfig,"",2));

        super(parent,globalFlow,subflowInternalFlowConfig);

        this.TYPE = 'subflow';
        this.subflowDef = subflowDef;
        this.subflowInstance = subflowInstance;
        this.node_map = node_map;
        this.path = parent.path+"/"+(subflowInstance._alias||subflowInstance.id);

        this.templateCredentials = credentials.get(subflowDef.id);
        this.instanceCredentials = credentials.get(this.id);

        var env = [];
        if (this.subflowDef.env) {
            this.subflowDef.env.forEach(e => {
                env[e.name] = e;
                if (e.type === "cred") {
                    e.value = this.templateCredentials[e.name];
                }
            });
        }
        if (this.subflowInstance.env) {
            this.subflowInstance.env.forEach(e => {
                var old = env[e.name];
                var ui = old ? old.ui : null;
                env[e.name] = e;
                if (ui) {
                    env[e.name].ui = ui;
                }
                if (e.type === "cred") {
                    if (!old || this.instanceCredentials.hasOwnProperty(e.name) ) {
                        e.value = this.instanceCredentials[e.name];
                    } else if (old) {
                        e.value = this.templateCredentials[e.name];
                    }
                }
            });
        }
        this.env = env;
    }

    /**
     * Start the subflow.
     * This creates a subflow instance node to handle the inbound messages. It also
     * rewires an subflow internal node that is connected to an output so it is connected
     * to the parent flow nodes the subflow instance is wired to.
     * @param  {[type]} diff [description]
     * @return {[type]}      [description]
     */
    start(diff) {
        var self = this;
        // Create a subflow node to accept inbound messages and route appropriately
        var Node = require("../Node");

        if (this.subflowDef.status) {
            var subflowStatusConfig = {
                id: this.subflowInstance.id+":status",
                type: "subflow-status",
                z: this.subflowInstance.id,
                _flow: this.parent
            }
            this.statusNode = new Node(subflowStatusConfig);
            this.statusNode.on("input", function(msg) {
                if (msg.payload !== undefined) {
                    if (typeof msg.payload === "string") {
                        // if msg.payload is a String, use it as status text
                        self.node.status({text:msg.payload})
                        return;
                    } else if (Object.prototype.toString.call(msg.payload) === "[object Object]") {
                        if (msg.payload.hasOwnProperty('text') || msg.payload.hasOwnProperty('fill') || msg.payload.hasOwnProperty('shape') || Object.keys(msg.payload).length === 0) {
                            // msg.payload is an object that looks like a status object
                            self.node.status(msg.payload);
                            return;
                        }
                    }
                    // Anything else - inspect it and use as status text
                    var text = util.inspect(msg.payload);
                    if (text.length > 32) { text = text.substr(0,32) + "..."; }
                    self.node.status({text:text});
                } else if (msg.status !== undefined) {
                    // if msg.status exists
                    if (msg.status.hasOwnProperty("text") && msg.status.text.indexOf("common.") === 0) {
                        msg.status.text = "node-red:"+msg.status.text;
                    }
                    self.node.status(msg.status)
                }
            })
        }


        var subflowInstanceConfig = {
            id: this.subflowInstance.id,
            type: this.subflowInstance.type,
            z: this.subflowInstance.z,
            name: this.subflowInstance.name,
            wires: [],
            _flow: this
        }
        if (this.subflowDef.in) {
            subflowInstanceConfig.wires = this.subflowDef.in.map(function(n) { return n.wires.map(function(w) { return self.node_map[w.id].id;})})
            subflowInstanceConfig._originalWires = clone(subflowInstanceConfig.wires);
        }

        this.node = new Node(subflowInstanceConfig);
        this.node.on("input", function(msg) { this.send(msg);});
        this.node.on("close", function() { this.status({}); })
        this.node.status = status => this.parent.handleStatus(this.node,status);
        // Create a context instance
        console.log("Node.context",this.type,"id:",this._alias||this.id,"z:",this.z)
        this._context = context.get(this._alias||this.id,this.z);


        this.node._updateWires = this.node.updateWires;

        this.node.updateWires = function(newWires) {
            // Wire the subflow outputs
            if (self.subflowDef.out) {
                var node,wires,i,j;
                // Restore the original wiring to the internal nodes
                subflowInstanceConfig.wires = clone(subflowInstanceConfig._originalWires);
                for (i=0;i<self.subflowDef.out.length;i++) {
                    wires = self.subflowDef.out[i].wires;
                    for (j=0;j<wires.length;j++) {
                        if (wires[j].id != self.subflowDef.id) {
                            node = self.node_map[wires[j].id];
                            if (node._originalWires) {
                                node.wires = clone(node._originalWires);
                            }
                        }
                    }
                }

                var modifiedNodes = {};
                var subflowInstanceModified = false;
                for (i=0;i<self.subflowDef.out.length;i++) {
                    wires = self.subflowDef.out[i].wires;
                    for (j=0;j<wires.length;j++) {
                        if (wires[j].id === self.subflowDef.id) {
                            subflowInstanceConfig.wires[wires[j].port] = subflowInstanceConfig.wires[wires[j].port].concat(newWires[i]);
                            subflowInstanceModified = true;
                        } else {
                            node = self.node_map[wires[j].id];
                            node.wires[wires[j].port] = node.wires[wires[j].port].concat(newWires[i]);
                            modifiedNodes[node.id] = node;
                        }
                    }
                }
                Object.keys(modifiedNodes).forEach(function(id) {
                    var node = modifiedNodes[id];
                    self.activeNodes[id].updateWires(node.wires);
                });

                if (subflowInstanceModified) {
                    self.node._updateWires(subflowInstanceConfig.wires);
                }
            }
        };

        // Wire the subflow outputs
        if (this.subflowDef.out) {
            for (var i=0;i<this.subflowDef.out.length;i++) {
                // i: the output index
                // This is what this Output is wired to
                var wires = this.subflowDef.out[i].wires;
                for (var j=0;j<wires.length;j++) {
                    if (wires[j].id === this.subflowDef.id) {
                        // A subflow input wired straight to a subflow output
                        subflowInstanceConfig.wires[wires[j].port] = subflowInstanceConfig.wires[wires[j].port].concat(this.subflowInstance.wires[i])
                        this.node._updateWires(subflowInstanceConfig.wires);
                    } else {
                        var node = self.node_map[wires[j].id];
                        if (!node._originalWires) {
                            node._originalWires = clone(node.wires);
                        }
                        node.wires[wires[j].port] = (node.wires[wires[j].port]||[]).concat(this.subflowInstance.wires[i]);
                    }
                }
            }
        }

        if (this.subflowDef.status) {
            var subflowStatusId = this.statusNode.id;
            wires = this.subflowDef.status.wires;
            for (var j=0;j<wires.length;j++) {
                if (wires[j].id === this.subflowDef.id) {
                    // A subflow input wired straight to a subflow output
                    subflowInstanceConfig.wires[wires[j].port].push(subflowStatusId);
                    this.node._updateWires(subflowInstanceConfig.wires);
                } else {
                    var node = self.node_map[wires[j].id];
                    if (!node._originalWires) {
                        node._originalWires = clone(node.wires);
                    }
                    node.wires[wires[j].port] = (node.wires[wires[j].port]||[]);
                    node.wires[wires[j].port].push(subflowStatusId);
                }
            }
        }
        super.start(diff);
    }


    /**
     * Get environment variable of subflow
     * @param {String}   name   name of env var
     * @return {Object}  val    value of env var
     */
    getSetting(name) {
        if (!/^\$parent\./.test(name)) {
            var env = this.env;
            var is_info = name.endsWith("_info");
            var is_type = name.endsWith("_type");
            var ename = (is_info || is_type) ? name.substring(0, name.length -5) : name; // 5 = length of "_info"/"_type"

            if (env && env.hasOwnProperty(ename)) {
                var val = env[ename];
                if (is_type) {
                    return val ? val.type : undefined;
                }
                // If this is an env type property we need to be careful not
                // to get into lookup loops.
                // 1. if the value to lookup is the same as this one, go straight to parent
                // 2. otherwise, check if it is a compound env var ("foo $(bar)")
                //    and if so, substitute any instances of `name` with $parent.name
                // See https://github.com/node-red/node-red/issues/2099
                if (val.type !== 'env' || val.value !== name) {
                    let value = val.value;
                    var type = val.type;
                    if (type === 'env') {
                        value = value.replace(new RegExp("\\${"+name+"}","g"),"${$parent."+name+"}");
                    }
                    try {
                        var ret = evaluateInputValue(value, type, this.node);
                        if (is_info) {
                            return composeInfo(val, ret);
                        }
                        return ret;
                    }
                    catch (e) {
                        this.error(e);
                        return undefined;
                    }
                } else {
                    // This _is_ an env property pointing at itself - go to parent
                }
            }
        } else {
            // name starts $parent. ... so delegate to parent automatically
            name = name.substring(8);
        }
        var parent = this.parent;
        if (parent) {
            var val = parent.getSetting(name);
            return val;
        }
        return undefined;
    }

    /**
     * Get a node instance from this subflow.
     * If the subflow has a status node, check for that, otherwise use
     * the super-class function
     * @param  {String} id [description]
     * @param  {Boolean} cancelBubble    if true, prevents the flow from passing the request to the parent
     *                                   This stops infinite loops when the parent asked this Flow for the
     *                                   node to begin with.
     * @return {[type]}    [description]
     */
    getNode(id, cancelBubble) {
        if (this.statusNode && this.statusNode.id === id) {
            return this.statusNode;
        }
        return super.getNode(id,cancelBubble);
    }

    /**
     * Handle a status event from a node within this flow.
     * @param  {Node}    node          The original node that triggered the event
     * @param  {Object}  statusMessage The status object
     * @param  {Node}    reportingNode The node emitting the status event.
     *                                 This could be a subflow instance node when the status
     *                                 is being delegated up.
     * @param  {boolean} muteStatus    Whether to emit the status event
     * @return {[type]}               [description]
     */
    handleStatus(node,statusMessage,reportingNode,muteStatus) {
        let handled = super.handleStatus(node,statusMessage,reportingNode,muteStatus);
        if (!handled) {
            if (!this.statusNode || node === this.node) {
                // No status node on this subflow caught the status message.
                // AND there is no Subflow Status node - so the user isn't
                // wanting to manage status messages themselves
                // Pass up to the parent with this subflow's instance as the
                // reporting node
                handled = this.parent.handleStatus(node,statusMessage,this.node,true);
            }
        }
        return handled;

    }

    /**
     * Handle an error event from a node within this flow. If there are no Catch
     * nodes within this flow, pass the event to the parent flow.
     * @param  {[type]} node          [description]
     * @param  {[type]} logMessage    [description]
     * @param  {[type]} msg           [description]
     * @param  {[type]} reportingNode [description]
     * @return {[type]}               [description]
     */
    handleError(node,logMessage,msg,reportingNode) {
        let handled = super.handleError(node,logMessage,msg,reportingNode);
        if (!handled) {
            // No catch node on this subflow caught the error message.
            // Pass up to the parent with the subflow's instance as the
            // reporting node.
            handled = this.parent.handleError(node,logMessage,msg,this.node);
        }
        return handled;
    }
}


/**
 * Clone a node definition for use within a subflow instance.
 * Give the node a new id and set its _alias property to record
 * its association with the original node definition.
 * @param  {[type]} subflowInstanceId [description]
 * @param  {[type]} def               [description]
 * @return {[type]}                   [description]
 */
function createNodeInSubflow(subflowInstanceId, def) {
    let node = clone(def);
    let nid = redUtil.generateId();
    // console.log("Create Node In subflow",node._alias, "--->",nid, "(",node.type,")")
    // node_map[node.id] = node;
    node._alias = node.id;
    node.id = nid;
    node.z = subflowInstanceId;
    return node;
}


/**
 * Given an object of {id:nodes} and a map of {old-id:node}, modifiy all
 * properties in the nodes object to reference the new node ids.
 * This handles:
 *  - node.wires,
 *  - node.scope of Complete, Catch and Status nodes,
 *  - node.XYZ for any property where XYZ is recognised as an old property
 * @param  {[type]} nodes   [description]
 * @param  {[type]} nodeMap [description]
 * @return {[type]}         [description]
 */
function remapSubflowNodes(nodes,nodeMap) {
    for (var id in nodes) {
        if (nodes.hasOwnProperty(id)) {
            var node = nodes[id];
            if (node.wires) {
                var outputs = node.wires;
                for (j=0;j<outputs.length;j++) {
                    wires = outputs[j];
                    for (k=0;k<wires.length;k++) {
                        if (nodeMap[outputs[j][k]]) {
                            outputs[j][k] = nodeMap[outputs[j][k]].id
                        } else {
                            outputs[j][k] = null;
                        }
                    }
                }
            }
            if ((node.type === 'complete' || node.type === 'catch' || node.type === 'status') && node.scope) {
                node.scope = node.scope.map(function(id) {
                    return nodeMap[id]?nodeMap[id].id:""
                })
            } else {
                for (var prop in node) {
                    if (node.hasOwnProperty(prop) && prop !== '_alias') {
                        if (nodeMap[node[prop]]) {
                            node[prop] = nodeMap[node[prop]].id;
                        }
                    }
                }
            }
        }
    }
}

function createSubflow(parent,globalFlow,subflowDef,subflowInstance) {
    return new Subflow(parent,globalFlow,subflowDef,subflowInstance)
}

module.exports = {
    init: function(runtime) {
        Log = runtime.log;
    },
    create: createSubflow
}