/* valaccodegeneratorsourcefile.vala
 *
 * Copyright (C) 2006-2007  Jürg Billeter, Raffaele Sandrini
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.

 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.

 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
 *
 * Author:
 * 	Jürg Billeter <j@bitron.ch>
 *	Raffaele Sandrini <rasa@gmx.ch>
 */

using GLib;
using Gee;

public class Vala.CCodeGenerator {
	private CCodeIncludeDirective get_internal_include (string! filename) {
		return new CCodeIncludeDirective (filename, context.library == null);
	}

	private CCodeForStatement get_vala_array_free_loop (bool have_length) {
		var cbody = new CCodeBlock ();
		var cptrarray = new CCodeCastExpression (new CCodeIdentifier ("array"), "gpointer*");
		var cea = new CCodeElementAccess (cptrarray, new CCodeIdentifier ("i"));

		var cfreecall = new CCodeFunctionCall (new CCodeIdentifier ("destroy_func"));
		cfreecall.add_argument (cea);

		CCodeExpression cforcond;

		if (have_length) {
			var cfreecond = new CCodeBinaryExpression (CCodeBinaryOperator.INEQUALITY, cea, new CCodeConstant ("NULL"));
			cforcond = new CCodeBinaryExpression (CCodeBinaryOperator.LESS_THAN, new CCodeIdentifier ("i"), new CCodeIdentifier ("array_length"));
			cbody.add_statement (new CCodeIfStatement (cfreecond, new CCodeExpressionStatement (cfreecall)));
		} else {
			cforcond = new CCodeBinaryExpression (CCodeBinaryOperator.INEQUALITY, cea, new CCodeConstant ("NULL"));
			cbody.add_statement (new CCodeExpressionStatement (cfreecall));
		}

		var cfor = new CCodeForStatement (cforcond, cbody);
		cfor.add_initializer (new CCodeAssignment (new CCodeIdentifier ("i"), new CCodeConstant ("0")));
		cfor.add_iterator (new CCodeAssignment (new CCodeIdentifier ("i"), new CCodeBinaryExpression (CCodeBinaryOperator.PLUS, new CCodeIdentifier ("i"), new CCodeConstant ("1"))));

		return cfor;
	}

	private void append_vala_array_free () {
		var fun = new CCodeFunction ("_vala_array_free", "void");
		fun.modifiers = CCodeModifiers.STATIC;
		fun.add_parameter (new CCodeFormalParameter ("array", "gpointer"));
		fun.add_parameter (new CCodeFormalParameter ("array_length", "gint"));
		fun.add_parameter (new CCodeFormalParameter ("destroy_func", "GDestroyNotify"));
		source_type_member_declaration.append (fun.copy ());

		var cdofree = new CCodeBlock ();

		var citdecl = new CCodeDeclaration ("int");
		citdecl.add_declarator (new CCodeVariableDeclarator ("i"));
		cdofree.add_statement (citdecl);

		var clencheck = new CCodeBinaryExpression (CCodeBinaryOperator.GREATER_THAN_OR_EQUAL, new CCodeIdentifier ("array_length"), new CCodeConstant ("0"));
		var ciflen = new CCodeIfStatement (clencheck, get_vala_array_free_loop (true), get_vala_array_free_loop (false));
		cdofree.add_statement (ciflen);

		var ccondarr = new CCodeBinaryExpression (CCodeBinaryOperator.INEQUALITY, new CCodeIdentifier ("array"), new CCodeConstant ("NULL"));
		var ccondfunc = new CCodeBinaryExpression (CCodeBinaryOperator.INEQUALITY, new CCodeIdentifier ("destroy_func"), new CCodeConstant ("NULL"));
		var cif = new CCodeIfStatement (new CCodeBinaryExpression (CCodeBinaryOperator.AND, ccondarr, ccondfunc), cdofree);
		fun.block = new CCodeBlock ();
		fun.block.add_statement (cif);

		var carrfree = new CCodeFunctionCall (new CCodeIdentifier ("g_free"));
		carrfree.add_argument (new CCodeIdentifier ("array"));
		fun.block.add_statement (new CCodeExpressionStatement (carrfree));

		source_type_member_definition.append (fun);
	}

	private void append_vala_array_move () {
		string_h_needed = true;

		// assumes that overwritten array elements are null before invocation
		// FIXME will leak memory if that's not the case
		var fun = new CCodeFunction ("_vala_array_move", "void");
		fun.modifiers = CCodeModifiers.STATIC;
		fun.add_parameter (new CCodeFormalParameter ("array", "gpointer"));
		fun.add_parameter (new CCodeFormalParameter ("element_size", "gsize"));
		fun.add_parameter (new CCodeFormalParameter ("src", "gint"));
		fun.add_parameter (new CCodeFormalParameter ("dest", "gint"));
		fun.add_parameter (new CCodeFormalParameter ("length", "gint"));
		source_type_member_declaration.append (fun.copy ());

		var array = new CCodeIdentifier ("array");
		var element_size = new CCodeIdentifier ("element_size");
		var length = new CCodeIdentifier ("length");
		var src = new CCodeIdentifier ("src");
		var dest = new CCodeIdentifier ("dest");
		var src_address = new CCodeBinaryExpression (CCodeBinaryOperator.PLUS, array, new CCodeBinaryExpression (CCodeBinaryOperator.MUL, src, element_size));
		var dest_address = new CCodeBinaryExpression (CCodeBinaryOperator.PLUS, array, new CCodeBinaryExpression (CCodeBinaryOperator.MUL, dest, element_size));
		var dest_end_address = new CCodeBinaryExpression (CCodeBinaryOperator.PLUS, array, new CCodeBinaryExpression (CCodeBinaryOperator.MUL, new CCodeParenthesizedExpression (new CCodeBinaryExpression (CCodeBinaryOperator.PLUS, dest, length)), element_size));

		fun.block = new CCodeBlock ();

		var ccall = new CCodeFunctionCall (new CCodeIdentifier ("g_memmove"));
		ccall.add_argument (dest_address);
		ccall.add_argument (src_address);
		ccall.add_argument (new CCodeBinaryExpression (CCodeBinaryOperator.MUL, length, element_size));
		fun.block.add_statement (new CCodeExpressionStatement (ccall));

		var czero1 = new CCodeFunctionCall (new CCodeIdentifier ("memset"));
		czero1.add_argument (src_address);
		czero1.add_argument (new CCodeConstant ("0"));
		czero1.add_argument (new CCodeBinaryExpression (CCodeBinaryOperator.MUL, new CCodeParenthesizedExpression (new CCodeBinaryExpression (CCodeBinaryOperator.MINUS, dest, src)), element_size));
		var czeroblock1 = new CCodeBlock ();
		czeroblock1.add_statement (new CCodeExpressionStatement (czero1));

		var czero2 = new CCodeFunctionCall (new CCodeIdentifier ("memset"));
		czero2.add_argument (dest_end_address);
		czero2.add_argument (new CCodeConstant ("0"));
		czero2.add_argument (new CCodeBinaryExpression (CCodeBinaryOperator.MUL, new CCodeParenthesizedExpression (new CCodeBinaryExpression (CCodeBinaryOperator.MINUS, src, dest)), element_size));
		var czeroblock2 = new CCodeBlock ();
		czeroblock2.add_statement (new CCodeExpressionStatement (czero2));

		fun.block.add_statement (new CCodeIfStatement (new CCodeBinaryExpression (CCodeBinaryOperator.LESS_THAN, src, dest), czeroblock1, czeroblock2));

		source_type_member_definition.append (fun);
	}

	public override void visit_source_file (SourceFile! source_file) {
		header_begin = new CCodeFragment ();
		header_type_declaration = new CCodeFragment ();
		header_type_definition = new CCodeFragment ();
		header_type_member_declaration = new CCodeFragment ();
		source_begin = new CCodeFragment ();
		source_include_directives = new CCodeFragment ();
		source_type_member_declaration = new CCodeFragment ();
		source_type_member_definition = new CCodeFragment ();
		source_signal_marshaller_definition = new CCodeFragment ();
		source_signal_marshaller_declaration = new CCodeFragment ();
		
		user_marshal_set = new HashSet<string> (str_hash, str_equal);
		
		next_temp_var_id = 0;
		
		string_h_needed = false;
		requires_free_checked = false;
		requires_array_free = false;
		requires_array_move = false;
		
		header_begin.append (new CCodeIncludeDirective ("glib.h"));
		header_begin.append (new CCodeIncludeDirective ("glib-object.h"));
		source_include_directives.append (new CCodeIncludeDirective (source_file.get_cheader_filename (), true));
		
		Gee.List<string> used_includes = new ArrayList<string> (str_equal);
		used_includes.add ("glib.h");
		used_includes.add ("glib-object.h");
		used_includes.add (source_file.get_cheader_filename ());
		
		foreach (string filename in source_file.get_header_external_includes ()) {
			if (!used_includes.contains (filename)) {
				header_begin.append (new CCodeIncludeDirective (filename));
				used_includes.add (filename);
			}
		}
		foreach (string filename in source_file.get_header_internal_includes ()) {
			if (!used_includes.contains (filename)) {
				header_begin.append (get_internal_include (filename));
				used_includes.add (filename);
			}
		}
		foreach (string filename in source_file.get_source_external_includes ()) {
			if (!used_includes.contains (filename)) {
				source_include_directives.append (new CCodeIncludeDirective (filename));
				used_includes.add (filename);
			}
		}
		foreach (string filename in source_file.get_source_internal_includes ()) {
			if (!used_includes.contains (filename)) {
				source_include_directives.append (get_internal_include (filename));
				used_includes.add (filename);
			}
		}
		if (source_file.is_cycle_head) {
			foreach (SourceFile cycle_file in source_file.cycle.files) {
				foreach (CodeNode node in cycle_file.get_nodes ()) {
					if (node is Struct) {
						var st = (Struct) node;
						header_type_declaration.append (new CCodeTypeDefinition ("struct _%s".printf (st.get_cname ()), new CCodeVariableDeclarator (st.get_cname ())));
					} else if (node is Class) {
						var cl = (Class) node;
						header_type_declaration.append (new CCodeTypeDefinition ("struct _%s".printf (cl.get_cname ()), new CCodeVariableDeclarator (cl.get_cname ())));
						header_type_declaration.append (new CCodeTypeDefinition ("struct _%sClass".printf (cl.get_cname ()), new CCodeVariableDeclarator ("%sClass".printf (cl.get_cname ()))));
					} else if (node is Interface) {
						var iface = (Interface) node;
						header_type_declaration.append (new CCodeTypeDefinition ("struct _%s".printf (iface.get_cname ()), new CCodeVariableDeclarator (iface.get_cname ())));
						header_type_declaration.append (new CCodeTypeDefinition ("struct _%s".printf (iface.get_type_cname ()), new CCodeVariableDeclarator (iface.get_type_cname ())));
					}
				}
			}
		}

		source_file.accept_children (this);

		var header_define = get_define_for_filename (source_file.get_cheader_filename ());
		
		/* generate hardcoded "well-known" macros */
		if (requires_free_checked) {
			source_begin.append (new CCodeMacroReplacement ("VALA_FREE_CHECKED(o,f)", "((o) == NULL ? NULL : ((o) = (f (o), NULL)))"));
		}
		if (requires_array_free) {
			append_vala_array_free ();
		}
		if (requires_array_move) {
			append_vala_array_move ();
		}
		
		if (string_h_needed) {
			source_include_directives.append (new CCodeIncludeDirective ("string.h"));
		}

		CCodeComment comment = null;
		if (source_file.comment != null) {
			comment = new CCodeComment (source_file.comment);
		}

		var writer = new CCodeWriter (source_file.get_cheader_filename ());
		if (comment != null) {
			comment.write (writer);
		}
		writer.write_newline ();
		var once = new CCodeOnceSection (header_define);
		once.append (new CCodeNewline ());
		once.append (header_begin);
		once.append (new CCodeNewline ());
		once.append (new CCodeIdentifier ("G_BEGIN_DECLS"));
		once.append (new CCodeNewline ());
		once.append (new CCodeNewline ());
		once.append (header_type_declaration);
		once.append (new CCodeNewline ());
		once.append (header_type_definition);
		once.append (new CCodeNewline ());
		once.append (header_type_member_declaration);
		once.append (new CCodeNewline ());
		once.append (new CCodeIdentifier ("G_END_DECLS"));
		once.append (new CCodeNewline ());
		once.append (new CCodeNewline ());
		once.write (writer);
		writer.close ();
		
		writer = new CCodeWriter (source_file.get_csource_filename ());
		writer.line_directives = context.debug;
		if (comment != null) {
			comment.write (writer);
		}
		source_begin.write (writer);
		writer.write_newline ();
		source_include_directives.write (writer);
		writer.write_newline ();
		source_type_member_declaration.write_declaration (writer);
		source_type_member_declaration.write (writer);
		writer.write_newline ();
		source_signal_marshaller_declaration.write_declaration (writer);
		source_signal_marshaller_declaration.write (writer);
		writer.write_newline ();
		source_type_member_definition.write (writer);
		writer.write_newline ();
		source_signal_marshaller_definition.write (writer);
		writer.write_newline ();
		writer.close ();

		header_begin = null;
		header_type_declaration = null;
		header_type_definition = null;
		header_type_member_declaration = null;
		source_begin = null;
		source_include_directives = null;
		source_type_member_declaration = null;
		source_type_member_definition = null;
		source_signal_marshaller_definition = null;
		source_signal_marshaller_declaration = null;
	}
	
	private static string get_define_for_filename (string! filename) {
		var define = new String ("__");
		
		var i = filename;
		while (i.len () > 0) {
			var c = i.get_char ();
			if (c.isalnum  () && c < 0x80) {
				define.append_unichar (c.toupper ());
			} else {
				define.append_c ('_');
			}
		
			i = i.next_char ();
		}
		
		define.append ("__");
		
		return define.str;
	}
}