///////////////////////////////////////////////////////////////////////////////
//
//  Microsoft Research Singularity
//
//  Copyright (c) Microsoft Corporation.  All rights reserved.
//
//  File:   Manifest.cs
//
//  Note:   Creates and binds endpoints using a manifest.
//

using System;
using System.Text;
using System.Collections;

using Microsoft.SingSharp;
using Microsoft.Singularity;
using Microsoft.Singularity.Channels;
using Microsoft.Singularity.Directory;
using Microsoft.Singularity.Extending;
using Microsoft.Singularity.Io;
using Microsoft.Singularity.Memory;
using Microsoft.Singularity.Xml;

namespace Microsoft.Singularity.Applications
{

    /// <summary>
    /// This is a placeholder class for an application's manifest.
    /// At present the application manifest is represented by a hashtable.
    /// The hashtable has several important properties:
    ///  - name: the name of the application
    ///  - path: path to the application executable
    /// </summary>
    public class Manifest
    {
        /// <summary>
        /// We treat the application manifest as a collection of
        /// key, value pairs.
        /// </summary>


        private Hashtable! data = new Hashtable();
        private const string pipeContract = "Microsoft.Singularity.Io.UnicodePipeContract"; 
        
        private string name;
        private string path;

        private readonly XmlNode!       applicationNode;
        private readonly XmlNode!       processNode;
        private readonly XmlNode        actionNode;
        private readonly XmlNode        categoriesNode;
        private readonly XmlNode        stringParametersNode;
        private readonly XmlNode        stringArrayParametersNode;
        private readonly XmlNode        longParametersNode;
        private readonly XmlNode        boolParametersNode;
        private static StringBuilder    sb; 

        /// <summary>
        /// Create a manifest object from the given xml representation
        /// </summary>

        [Microsoft.Contracts.NotDelayed]
        public Manifest(byte[] xml)
        {
            XmlReader! reader = new XmlReader(xml);
            XmlNode! doc = (!)reader.Parse();

            this(doc);
        }

        [Microsoft.Contracts.NotDelayed]
        private Manifest(XmlNode! doc)
        {
            XmlNode app = (!)doc.GetChild("application");
            name = app["name"];
            XmlNode proc = null;
            foreach (XmlNode! process in app.Children) {
                if (process.Name != "process") {
                    continue;
                }
                if (process.GetAttribute("main", "false") == "true") {
                    path = process["path"];
                    proc = process;
                    break;
                }
            }
            applicationNode = (!)app;
            XmlNode! processNode = this.processNode = (!)proc;
            base();
            
            categoriesNode = processNode.GetChild("categories");
            
            if (categoriesNode != null) {
                    return;
            }
            else {
                DebugStub.WriteLine("::: no category");
            }
        }

        public XmlNode GetCategoriesNode()
        {
            return categoriesNode; 
        }


        public void SetProperty(object! name, object value)
        {
            data[name] = value;
        }

        public string Name
        {
            get {
                return name;
            }
        }

        public string Path
        {
            get {
                return path;
            }
        }

        public  string  GetHelpMessage(XmlNode categoryNode)
        {
                return categoryNode == null?  null :  categoryNode.GetAttribute("HelpMessage", null);
        }
        
        
        // given an action find the corresponding category node
        public  XmlNode GetCategoryNode(string actionName) {
            if (categoriesNode == null) {
                //Console.WriteLine("GetCategoryNode: no categories!");
                return null; 
            }
            if (actionName == null) {
                // return the 1st one if there is one
                //Console.WriteLine("GetCategoryNode: Selecting default!");
                XmlNode n = categoriesNode.GetChild("category");
                if (n == null) { 
                        return null; 
               } 
               else return n; 
            }
            else {
                foreach (XmlNode! c in categoriesNode.Children) {
                    string a = c.GetAttribute("Action",null);
                    //Console.WriteLine("action= {0}.",a);
                    if ( a != null && a == actionName) {
                        //Console.WriteLine("found a match for action {0}",actionName); 
                        return c; 
                    }
                }
                return null; 
            }
        }
        
        public  XmlNode GetBoolParameterNode(XmlNode! category)
        {
            return category.GetChild("BoolParameters");
        }

        public  XmlNode GetStringArrayParameterNode(XmlNode! category)
        {
            return category.GetChild("StringArrayParameters");
        }

        public  XmlNode GetStringParameterNode(XmlNode! category)
        {
            return category.GetChild("StringParameters");
        }

        public  XmlNode GetLongParameterNode(XmlNode! category)
        {
            return category.GetChild("LongParameters");
        }
        
        public bool HasParameters() 
        {
            return (categoriesNode != null);
        }

#if false
        public void ShowParameters()
        {
            if (categoryNode == null) {
                Console.WriteLine("::: no category");
                return; 
            }  
            if (stringParametersNode == null) {
                Console.WriteLine("::: no strings");
            }  
            if (longParametersNode == null) {
                Console.WriteLine("::: no integers");
            }  
        }
#endif 
        public int SetEndpoints(Process process, string action, bool show)
        {
            // walk the XmlTree looking endpoints
            // these will be used by the binder to setup and transfer to
            // the starting process much like what is done for drivers

            XmlNode categoryNode = GetCategoryNode(action); 
            //Console.WriteLine(" Set endpoints"); 
            if (categoryNode == null) {
                Console.WriteLine("No endpoints in console app!"); 
                //DebugStub.Break(); 
                return 0;
            }

            XmlNode endpoints = categoryNode.GetChild("endpoints");
            if (endpoints == null) {
                //DebugStub.Break(); 
                return 0;
            }
            int endpointCount = endpoints.GetAttribute("length", 0);
            if (endpointCount == 0) {
                DebugStub.Break(); 
                return 0;
            }

            //fill in ep set
            foreach (XmlNode! endpoint in endpoints.Children) {
                string! contract
                    = (!)endpoint.GetAttribute("contractName", "");
                int index = endpoint.GetAttribute("id", -1);

                if (endpoint.Name == "endpoint") {
                    // FIXFIX -- if it is a pipe ignore it for now
                    if (show) {
                        Console.WriteLine(" endpoint: {0}", contract); 
                    } 
                    else {
                        if (contract != pipeContract) {
                            // get a pre-bound generic endpoint to a service from the
                            // resource tracker
                            if (process == null) {
                                throw new Exception("Process arg was null.");
                            }
                            if (!Binder.BindServiceUser(process, index, contract, endpoint)) {
                                return -1;
                            }
                        }
                        else { 
                            DebugStub.WriteLine("shell.manifest.SetEndpoints: skipping pipe at {0}", __arglist(index));
                        } 
                    }
                }
            }
            return endpointCount;
        }
        
#if false
        public override string! ToString()
        {
            StringBuilder sb = new StringBuilder();

            sb.AppendFormat("<application name=\"{0}\">", Name);

            // the main executable
            sb.AppendFormat("<process main=\"true\" path=\"{0}\"/>", Path);

            foreach(DataItem item in data.Values) {
                if (item.Directory == null) {
                    sb.AppendFormat("<data name=\"{0}\" value=\"{1}\"/>",
                                    item.Name, item.Value);
                }
                else {
                    sb.AppendFormat("<data namespace=\"{0}\" name=\"{1}\" value=\"{2}\"/>",
                                    item.Directory, item.Name, item.Value);
                }
            }

            sb.Append("</process>");
            sb.Append("</application>");
            sb.Append("<signature>");
            sb.Append("</signature>");

            return sb.ToString();
        }

        public byte[] Serialize()
        {
            return (new UTF8Encoding()).GetBytes(ToString());
        }
#endif
    }
}