//------------------------------------------------------------------------------
// <copyright file="QilPatternFactory.cs" company="Microsoft">
//     Copyright (c) Microsoft Corporation.  All rights reserved.
// </copyright>
// <owner current="true" primary="true">Microsoft</owner>
//------------------------------------------------------------------------------

using System.Collections.Generic;
using System.Diagnostics;
using System.Reflection;
using System.Xml.Schema;

namespace System.Xml.Xsl.Qil {

    /// <summary>
    /// Additional factory methods for constructing common QIL patterns.
    /// </summary>
    /// <remarks>
    /// Some of the methods here are exactly like the ones in QilFactory except
    /// that they perform constant-folding and other normalization.  Others are
    /// "macro patterns" that simplify the task of constructing otherwise complex patterns.
    /// </remarks>
    internal class QilPatternFactory {
        private bool       debug;
        private QilFactory f;

        public QilPatternFactory(QilFactory f, bool debug) {
            Debug.Assert(f != null);
            this.f = f;
            this.debug = debug;
        }

        public QilFactory          BaseFactory { get { return f; } }
        public bool                IsDebug     { get { return this.debug; } }

        #region Convenience methods

        public QilLiteral String(string val) {
            return f.LiteralString(val);
        }

        public QilLiteral Int32(int val) {
            return f.LiteralInt32(val);
        }

        public QilLiteral Double(double val) {
            return f.LiteralDouble(val);
        }

        public QilName QName(string local, string uri, string prefix) {
            return f.LiteralQName(local, uri, prefix);
        }

        public QilName QName(string local, string uri) {
            return f.LiteralQName(local, uri, System.String.Empty);
        }

        public QilName QName(string local) {
            return f.LiteralQName(local, System.String.Empty, System.String.Empty);
        }

        public QilNode Unknown(XmlQueryType t) {
            return f.Unknown(t);
        }
        #endregion

        #region meta
        //-----------------------------------------------
        // meta
        //-----------------------------------------------
        public QilExpression QilExpression(QilNode root, QilFactory factory) {
            return f.QilExpression(root, factory);
        }

        public QilList FunctionList() {
            return f.FunctionList();
        }

        public QilList GlobalVariableList() {
            return f.GlobalVariableList();
        }

        public QilList GlobalParameterList() {
            return f.GlobalParameterList();
        }

        public QilList ActualParameterList() {
            return f.ActualParameterList();
        }

        public QilList ActualParameterList(QilNode arg1) {
            QilList result = f.ActualParameterList();
            result.Add(arg1);
            return result;
        }

        public QilList ActualParameterList(QilNode arg1, QilNode arg2) {
            QilList result = f.ActualParameterList();
            result.Add(arg1);
            result.Add(arg2);
            return result;
        }

        public QilList ActualParameterList(params QilNode[] args) {
            return f.ActualParameterList(args);
        }

        public QilList FormalParameterList() {
            return f.FormalParameterList();
        }

        public QilList FormalParameterList(QilNode arg1) {
            QilList result = f.FormalParameterList();
            result.Add(arg1);
            return result;
        }

        public QilList FormalParameterList(QilNode arg1, QilNode arg2) {
            QilList result = f.FormalParameterList();
            result.Add(arg1);
            result.Add(arg2);
            return result;
        }

        public QilList FormalParameterList(params QilNode[] args) {
            return f.FormalParameterList(args);
        }

        public QilList SortKeyList() {
            return f.SortKeyList();
        }

        public QilList SortKeyList(QilSortKey key) {
            QilList list = f.SortKeyList();
            list.Add(key);
            return list;
        }

        public QilList BranchList(params QilNode[] args) {
            return f.BranchList(args);
        }

        public QilNode OptimizeBarrier(QilNode child) {
            return f.OptimizeBarrier(child);
        }

        #endregion // meta

        #region specials
        //-----------------------------------------------
        // specials
        //-----------------------------------------------
        public QilNode DataSource(QilNode name, QilNode baseUri) {
            return f.DataSource(name, baseUri);
        }

        public QilNode Nop(QilNode child) {
            return f.Nop(child);
        }

        public QilNode Error(QilNode text) {
            return f.Error(text);
        }

        public QilNode Warning(QilNode text) {
            return f.Warning(text);
        }

        #endregion // specials

        #region variables
        //-----------------------------------------------
        // variables
        //-----------------------------------------------
        public QilIterator For(QilNode binding) {
            return f.For(binding);
        }

        public QilIterator Let(QilNode binding) {
            return f.Let(binding);
        }

        public QilParameter Parameter(XmlQueryType t) {
            return f.Parameter(t);
        }

        public QilParameter Parameter(QilNode defaultValue, QilName name, XmlQueryType t) {
            return f.Parameter(defaultValue, name, t);
        }

        public QilNode PositionOf(QilIterator expr) {
            return f.PositionOf(expr);
        }

        #endregion // variables

        #region literals
        //-----------------------------------------------
        // literals
        //-----------------------------------------------
        public QilNode True() {
            return f.True();
        }

        public QilNode False() {
            return f.False();
        }

        public QilNode Boolean(bool b) {
            return b ? this.True() : this.False();
        }

        #endregion // literals

        #region boolean operators
        //-----------------------------------------------
        // boolean operators
        //-----------------------------------------------

        // ToDo: Why we have nulls here at all?
        private static void CheckLogicArg(QilNode arg) {
            Debug.Assert(arg != null, "Argulent shouldn't be null");
            Debug.Assert(arg.XmlType.TypeCode == XmlTypeCode.Boolean && arg.XmlType.IsSingleton,
                "The operand must be boolean-typed"
            );
        }

        public QilNode And(QilNode left, QilNode right) {
            CheckLogicArg(left);
            CheckLogicArg(right);

            if (! debug) {
                // True, True => True (right)          other, True => other (left)
                // True, False => False (right)        other, False => False (right)
                // True, other => other (right)        other, other => And
                if (left.NodeType == QilNodeType.True || right.NodeType == QilNodeType.False) {
                    return right;
                }
                if (left.NodeType == QilNodeType.False || right.NodeType == QilNodeType.True) {
                    return left;
                }
            }
            return f.And(left, right);
        }

        public QilNode Or(QilNode left, QilNode right) {
            CheckLogicArg(left);
            CheckLogicArg(right);

            if (! debug) {
                // True, True => True (left)           other, True => True (right)
                // True, False => True (left)          other, False => other (left)
                // True, other => True (left)          other, other => Or
                if (left.NodeType == QilNodeType.True || right.NodeType == QilNodeType.False) {
                    return left;
                }
                if (left.NodeType == QilNodeType.False || right.NodeType == QilNodeType.True) {
                    return right;
                }
            }
            return f.Or(left, right);
        }

        public QilNode Not(QilNode child) {
            if (! debug) {
                switch (child.NodeType) {
                case QilNodeType.True:
                    return f.False();
                case QilNodeType.False:
                    return f.True();
                case QilNodeType.Not:
                    return ((QilUnary) child).Child;
                }
            }
            return f.Not(child);
        }

        #endregion // boolean operators

        #region choice
        //-----------------------------------------------
        // choice
        //-----------------------------------------------

        public QilNode Conditional(QilNode condition, QilNode trueBranch, QilNode falseBranch) {
            if (! debug) {
                switch (condition.NodeType) {
                case QilNodeType.True:
                    return trueBranch;
                case QilNodeType.False:
                    return falseBranch;
                case QilNodeType.Not:
                    return this.Conditional(((QilUnary)condition).Child, falseBranch, trueBranch);
                }
            }
            return f.Conditional(condition, trueBranch, falseBranch);
        }

        public QilNode Choice(QilNode expr, QilList branches) {
            if (! debug) {
                switch (branches.Count) {
                case 1:
                    // If expr has no side effects, it will be eliminated by optimizer
                    return f.Loop(f.Let(expr), branches[0]);
                case 2:
                    return f.Conditional(f.Eq(expr, f.LiteralInt32(0)), branches[0], branches[1]);
                }
            }
            return f.Choice(expr, branches);
        }

        #endregion // choice

        #region collection operators
        //-----------------------------------------------
        // collection operators
        //-----------------------------------------------
        public QilNode Length(QilNode child) {
            return f.Length(child);
        }

        public QilNode Sequence() {
            return f.Sequence();
        }

        public QilNode Sequence(QilNode child) {
            if (! debug) {
                return child;
            }
            QilList res = f.Sequence();
            res.Add(child);
            return res;
        }

        public QilNode Sequence(QilNode child1, QilNode child2) {
            QilList res = f.Sequence();
            res.Add(child1);
            res.Add(child2);
            return res;
        }

        public QilNode Sequence(params QilNode[] args) {
            if (! debug) {
                switch(args.Length) {
                case 0 : return f.Sequence();
                case 1 : return args[0];
                }
            }
            QilList res = f.Sequence();
            foreach (QilNode n in args)
                res.Add(n);
            return res;
        }

        public QilNode Union(QilNode left, QilNode right) {
            return f.Union(left, right);
        }

        public QilNode Sum(QilNode collection) {
            return f.Sum(collection);
        }
        #endregion // collection operators

        #region arithmetic operators
        //-----------------------------------------------
        // arithmetic operators
        //-----------------------------------------------
        public QilNode Negate(QilNode child) {
            return f.Negate(child);
        }

        public QilNode Add(QilNode left, QilNode right) {
            return f.Add(left, right);
        }

        public QilNode Subtract(QilNode left, QilNode right) {
            return f.Subtract(left, right);
        }

        public QilNode Multiply(QilNode left, QilNode right) {
            return f.Multiply(left, right);
        }

        public QilNode Divide(QilNode left, QilNode right) {
            return f.Divide(left, right);
        }

        public QilNode Modulo(QilNode left, QilNode right) {
            return f.Modulo(left, right);
        }

        #endregion // arithmetic operators

        #region string operators
        //-----------------------------------------------
        // string operators
        //-----------------------------------------------
        public QilNode StrLength(QilNode str) {
            return f.StrLength(str);
        }

        public QilNode StrConcat(QilNode values) {
            if (! debug) {
                if (values.XmlType.IsSingleton)
                    return values;
            }
            return f.StrConcat(values);
        }

        public QilNode StrConcat(params QilNode[] args) {
            return StrConcat((IList<QilNode>)args);
        }

        public QilNode StrConcat(IList<QilNode> args) {
            if (! debug) {
                switch(args.Count) {
                case 0 :
                    return f.LiteralString(string.Empty);
                case 1 :
                    return StrConcat(args[0]);
                }
            }
            return StrConcat(f.Sequence(args));
        }

        public QilNode StrParseQName(QilNode str, QilNode ns) {
            return f.StrParseQName(str, ns);
        }
        #endregion // string operators

        #region value comparison operators
        //-----------------------------------------------
        // value comparison operators
        //-----------------------------------------------
        public QilNode Ne(QilNode left, QilNode right) {
            return f.Ne(left, right);
        }

        public QilNode Eq(QilNode left, QilNode right) {
            return f.Eq(left, right);
        }

        public QilNode Gt(QilNode left, QilNode right) {
            return f.Gt(left, right);
        }

        public QilNode Ge(QilNode left, QilNode right) {
            return f.Ge(left, right);
        }

        public QilNode Lt(QilNode left, QilNode right) {
            return f.Lt(left, right);
        }

        public QilNode Le(QilNode left, QilNode right) {
            return f.Le(left, right);
        }

        #endregion // value comparison operators

        #region node comparison operators
        //-----------------------------------------------
        // node comparison operators
        //-----------------------------------------------
        public QilNode Is(QilNode left, QilNode right) {
            return f.Is(left, right);
        }

        public QilNode After(QilNode left, QilNode right) {
            return f.After(left, right);
        }

        public QilNode Before(QilNode left, QilNode right) {
            return f.Before(left, right);
        }

        #endregion // node comparison operators

        #region loops
        //-----------------------------------------------
        // loops
        //-----------------------------------------------
        public QilNode Loop(QilIterator variable, QilNode body) {
            if (! debug) {
                //((Loop (For $Binding) ($Binding) ) => ($binding))
                if (body == variable.Binding) {
                    return body;
                }
            }
            return f.Loop(variable, body);
        }

        public QilNode Filter(QilIterator variable, QilNode expr) {
            if (! debug) {
                //((Filter (For $Binding) (True ) ) => ($binding))
                if (expr.NodeType == QilNodeType.True) {
                    return variable.Binding;
                }
                // The following optimization is not safe if the iterator has side effects
                //((Filter (For $Binding) (False) ) => (Sequence))
            }
            return f.Filter(variable, expr);
        }

        #endregion // loops

        #region sorting
        //-----------------------------------------------
        // sorting
        //-----------------------------------------------
        public QilNode Sort(QilIterator iter, QilNode keys) {
            return f.Sort(iter, keys);
        }

        public QilSortKey SortKey(QilNode key, QilNode collation) {
            return f.SortKey(key, collation);
        }

        public QilNode DocOrderDistinct(QilNode collection) {
            if (collection.NodeType == QilNodeType.DocOrderDistinct) {
                return collection;
            }
            return f.DocOrderDistinct(collection);
        }

        #endregion // sorting

        #region function definition and invocation
        //-----------------------------------------------
        // function definition and invocation
        //-----------------------------------------------
        public QilFunction Function(QilList args, QilNode sideEffects, XmlQueryType resultType) {
            Debug.Assert(args.NodeType == QilNodeType.FormalParameterList);
            return f.Function(args, sideEffects, resultType);
        }
        public QilFunction Function(QilList args, QilNode defn, QilNode sideEffects) {
            Debug.Assert(args.NodeType == QilNodeType.FormalParameterList);
            return f.Function(args, defn, sideEffects, defn.XmlType);
        }

        public QilNode Invoke(QilFunction func, QilList args) {
            Debug.Assert(args.NodeType == QilNodeType.ActualParameterList);
            Debug.Assert(func.Arguments.Count == args.Count);
            return f.Invoke(func, args);
        }
        #endregion // function definition and invocation

        #region XML navigation
        //-----------------------------------------------
        // XML navigation
        //-----------------------------------------------
        public QilNode Content(QilNode context) {
            return f.Content(context);
        }

        public QilNode Parent(QilNode context) {
            return f.Parent(context);
        }

        public QilNode Root(QilNode context) {
            return f.Root(context);
        }

        public QilNode XmlContext() {
            return f.XmlContext();
        }

        public QilNode Descendant(QilNode expr) {
            return f.Descendant(expr);
        }

        public QilNode DescendantOrSelf(QilNode context) {
            return f.DescendantOrSelf(context);
        }

        public QilNode Ancestor(QilNode expr) {
            return f.Ancestor(expr);
        }

        public QilNode AncestorOrSelf(QilNode expr) {
            return f.AncestorOrSelf(expr);
        }

        public QilNode Preceding(QilNode expr) {
            return f.Preceding(expr);
        }

        public QilNode FollowingSibling(QilNode expr) {
            return f.FollowingSibling(expr);
        }

        public QilNode PrecedingSibling(QilNode expr) {
            return f.PrecedingSibling(expr);
        }

        public QilNode NodeRange(QilNode left, QilNode right) {
            return f.NodeRange(left, right);
        }

        public QilBinary Deref(QilNode context, QilNode id) {
            return f.Deref(context, id);
        }
        #endregion // XML navigation

        #region XML construction
        //-----------------------------------------------
        // XML construction
        //-----------------------------------------------
        public QilNode ElementCtor(QilNode name, QilNode content) {
            return f.ElementCtor(name, content);
        }

        public QilNode AttributeCtor(QilNode name, QilNode val) {
            return f.AttributeCtor(name, val);
        }

        public QilNode CommentCtor(QilNode content) {
            return f.CommentCtor(content);
        }

        public QilNode PICtor(QilNode name, QilNode content) {
            return f.PICtor(name, content);
        }

        public QilNode TextCtor(QilNode content) {
            return f.TextCtor(content);
        }

        public QilNode RawTextCtor(QilNode content) {
            return f.RawTextCtor(content);
        }

        public QilNode DocumentCtor(QilNode child) {
            return f.DocumentCtor(child);
        }

        public QilNode NamespaceDecl(QilNode prefix, QilNode uri) {
            return f.NamespaceDecl(prefix, uri);
        }

        public QilNode RtfCtor(QilNode content, QilNode baseUri) {
            return f.RtfCtor(content, baseUri);
        }

        #endregion // XML construction

        #region Node properties
        //-----------------------------------------------
        // Node properties
        //-----------------------------------------------
        public QilNode NameOf(QilNode expr) {
            return f.NameOf(expr);
        }

        public QilNode LocalNameOf(QilNode expr) {
            return f.LocalNameOf(expr);
        }

        public QilNode NamespaceUriOf(QilNode expr) {
            return f.NamespaceUriOf(expr);
        }

        public QilNode PrefixOf(QilNode expr) {
            return f.PrefixOf(expr);
        }

        #endregion // Node properties

        #region Type operators
        //-----------------------------------------------
        // Type operators
        //-----------------------------------------------
        public QilNode TypeAssert(QilNode expr, XmlQueryType t) {
            return f.TypeAssert(expr, t);
        }

        public QilNode IsType(QilNode expr, XmlQueryType t) {
            Debug.Assert(t != null, "Type can't be null");
            return f.IsType(expr, t);
        }

        public QilNode IsEmpty(QilNode set) {
            return f.IsEmpty(set);
        }

        #endregion // Type operators

        #region XPath operators
        //-----------------------------------------------
        // XPath operators
        //-----------------------------------------------
        public QilNode XPathNodeValue(QilNode expr) {
            return f.XPathNodeValue(expr);
        }

        public QilNode XPathFollowing(QilNode expr) {
            return f.XPathFollowing(expr);
        }

        public QilNode XPathNamespace(QilNode expr) {
            return f.XPathNamespace(expr);
        }

        public QilNode XPathPreceding(QilNode expr) {
            return f.XPathPreceding(expr);
        }

        #endregion // XPath operators

        #region XSLT
        //-----------------------------------------------
        // XSLT
        //-----------------------------------------------
        public QilNode XsltGenerateId(QilNode expr) {
            return f.XsltGenerateId(expr);
        }

        public QilNode XsltInvokeEarlyBound(QilNode name, MethodInfo d, XmlQueryType t, IList<QilNode> args) {
            QilList list = f.ActualParameterList();
            list.Add(args);
            return f.XsltInvokeEarlyBound(name, f.LiteralObject(d), list, t);
        }

        public QilNode XsltInvokeLateBound(QilNode name, IList<QilNode> args) {
            QilList list = f.ActualParameterList();
            list.Add(args);
            return f.XsltInvokeLateBound(name, list);
        }

        public QilNode XsltCopy(QilNode expr, QilNode content) {
            return f.XsltCopy(expr, content);
        }

        public QilNode XsltCopyOf(QilNode expr) {
            return f.XsltCopyOf(expr);
        }

        public QilNode XsltConvert(QilNode expr, XmlQueryType t) {
            return f.XsltConvert(expr, t);
        }

        #endregion // XSLT
    }
}