compiler/src/php_generator.py

""" Thrift IDL PHP client stub generator
    
    This generated PHP class definitions and client stubs for a valid thrift IDL definition

    Author(s): Mark Slee(mclee@facebook.com), Marc Kwiatkowski (marc@facebook.com)

    $Id:
"""
import time

import os
import os.path
from string import Template
from thrift.parser import *
from thrift.generator import *

HEADER_COMMENT = """<?php
/**
 * Autogenerated by Thrift
 * ${date}
 *
 * DO NOT EDIT UNLESS YOU ARE SURE THAT YOU KNOW WHAT YOU ARE DOING
 */
 """

PHP_TYPES_HEADER = Template(HEADER_COMMENT+"""
require_once THRIFT_ROOT.\'/Thrift.php\';
""")

PHP_TYPES_FOOTER = Template("""
?>
""")

PHP_SERVICES_HEADER = Template(HEADER_COMMENT+"""

require_once THRIFT_ROOT.'/Thrift.php';
require_once dirname(__FILE__).\'/${source}_types.php\';

""")

PHP_SERVICES_FOOTER = Template("""
?>
""")

PHP_IMPL_HEADER = Template(HEADER_COMMENT+"""

require_once THRIFT_ROOT.'/Thrift.php';
require_once dirname(__FILE__).\'/${source}_types.php\';

""")

PHP_IMPL_FOOTER = Template("""
?>
""")

def php_debug(arg):
    print(arg)

class Indenter(object):
    def __init__(self, margin=4):
        self.margin = ''.join([' ' for ix in range(margin)])
        self.level = 0

    def __getitem__(self, level):
        return ''.join([self.margin for ix in range(level)])

    def __iadd__(self, value):
        self.level = self.level + value
        return self

    def __isub__(self, value):
        self.level = self.level - value
        return self

    def __call__(self):
        return self.__getitem__(self.level)

class Variable(object):
    def __init__(self, ttype, name):
        self.ttype = ttype
        self.name = name

    def toDeclaration(self, new=False):
	if not new:
	    defaultValue = defaultValueForType(self.ttype)
	else:
	    defaultValue = newInstanceForType(self.ttype)
        return self.name+" = "+defaultValue

class Scope(object):
    def __init__(self, parent=None):
        self.index = 0
        self.vars = {}
        self.parent = parent
	self.childIndex = 0
        if self.parent:
            self.level = self.parent.level + 1
	    self.index = self.parent.childIndex 
	    self.parent.childIndex+= 1
	    self.suffix = self.parent.suffix+str(self.index)
        else:
            self.level = 0
	    self.index = 0
	    self.suffix = ""

    def declare(self, ttype, name):
        if name in self.vars:
            raise Exception, "Variable \""+name+"\" already declared in this  scope."
	result = Variable(ttype, "$_"+name+self.suffix)
        self.vars[name] = result
        return result

    def get(self, var):
        if var.name in self.vars:
            return self.vars[var.name]
        elif self.parent:
            return self.parent.get(var)
        else:
            raise Exception, "Variable \""+var.name+"\" does not exist in any enclosing scope"

PHP_TYPE_PROTOCOL_MAP = {
    BOOL_TYPE : "Bool",
    STRING_TYPE: "String",
    UTF7_TYPE: "String",
    UTF8_TYPE: "Wstring",
    BYTE_TYPE : "Byte",
    I08_TYPE: "Byte",
    I16_TYPE: "I16",
    I32_TYPE: "I32",
    I64_TYPE: "I64",
    I16_TYPE: "I16",
    I32_TYPE: "I32",
    I64_TYPE: "I64",
    U08_TYPE: "Byte",
    U16_TYPE: "U16",
    U32_TYPE: "U32",
    U64_TYPE: "U64",
    U16_TYPE: "U16",
    U32_TYPE: "U32",
    U64_TYPE: "U64",
    FLOAT_TYPE: "Float",
    DOUBLE_TYPE: "Double"
   }
            
PHP_PRIMITIVE_TYPE_IO_METHOD_SUFFIX_MAP = {
    "void" :"Void",
    "bool" : "Bool",
    "string": "String",
    "utf7": "String",
    "utf8": "String", 
    "utf16": "String",
    "i08": "Byte",
    "i16": "I16",
    "i32": "I32", 
    "i64": "I64", 
    "u08": "Byte",
    "u16": "U16",
    "u32": "U32",
    "u64": "U64",
    "float": "Float",
    "double": "Double"
}

class CodeGenerator(object):
    def __init__(self,
                 scope=Scope(),
		 indent = Indenter()):
        self.scope = scope
	self.indent = indent

    def newScope(self):
	self.scope = Scope(self.scope)

    def oldScope(self):
	if not self.scope.parent:
	    raise Exception, "Unbalanced scope entry/exit"

	self.scope = self.scope.parent

    def declare(self, type, name, defaultValue=None):
        tvar = self.scope.declare(type, name)
        return tvar

    def toDeclaration(self, tvar, new=False):
	if not new:
	    defaultValue = defaultValueForType(tvar.ttype)
	else:
	    defaultValue = newInstanceForType(tvar.ttype)

        return self.indent()+tvar.name+" = "+defaultValue+";\n"

class Reader(CodeGenerator):
    def __init__(self,
                 iprot="$this->_iprot",
                 itrans="$this->_itrans",
                 scope=Scope(),
		 indent = Indenter()):
	CodeGenerator.__init__(self, scope, indent)
        self.iprot = iprot
        self.itrans = itrans

    def toReadMessageBegin(self, messageNameVar, seqidVar):
        return self.indent()+self.iprot+"->readMessageBegin("+self.itrans+", "+messageNameVar.name+", "+seqidVar.name+");\n"

    def toReadMessageEnd(self):
        return self.indent()+self.iprot+"->readMessageEnd("+self.itrans+");\n"

    def toReadStructBegin(self, structNameVar):
        return self.indent()+self.iprot+"->readStructBegin("+self.itrans+", "+structNameVar.name+");\n"

    def toReadStructEnd(self):
        return self.indent()+self.iprot+"->readStructEnd("+self.itrans+");\n"

    def toReadMapBegin(self, keyTypeVar, valueTypeVar, sizeVar):
        return self.indent()+self.iprot+"->readMapBegin("+self.itrans+", "+keyTypeVar.name+", "+valueTypeVar.name+", "+sizeVar.name+");\n"

    def toReadMapEnd(self):
        return self.indent()+self.iprot+"->readMapEnd("+self.itrans+");\n"

    def toReadSetBegin(self, valueTypeVar, sizeVar):
        return self.indent()+self.iprot+"->readSetBegin("+self.itrans+", "+valueTypeVar.name+", "+sizeVar.name+");\n"

    def toReadSetEnd(self):
        return self.indent()+self.iprot+"->readSetEnd("+self.itrans+");\n"

    def toReadListBegin(self, valueTypeVar, sizeVar):
        return self.indent()+self.iprot+"->readListBegin("+self.itrans+", "+valueTypeVar.name+", "+sizeVar.name+");\n"

    def toReadListEnd(self):
        return self.indent()+self.iprot+"->readListEnd("+self.itrans+");\n"

    def toReadFieldBegin(self, fieldNameVar, fieldTypeVar, fieldIdVar):
        return self.indent()+self.iprot+"->readFieldBegin("+self.itrans+", "+fieldNameVar.name+", "+fieldTypeVar.name+", "+fieldIdVar.name+");\n"

    def toReadFieldEnd(self):
        return self.indent()+self.iprot+"->readFieldEnd("+self.itrans+");\n"

    def toSkipField(self, fieldTypeVar):
        return self.indent()+self.iprot+"->skipField("+self.itrans+", "+fieldTypeVar.name+");\n"

    def toReadPrimitive(self, value, suffix):
        return self.indent()+value+" = "+self.iprot+"->read"+suffix+"("+self.itrans+");\n"

    def toRead(self, value, ttype):

        if isinstance(ttype, PrimitiveType):
            return self.toReadPrimitive(value, PHP_TYPE_PROTOCOL_MAP[ttype])

        elif isinstance(ttype, StructType):
	    self.newScope()
            result = self.toReadStruct(value, ttype)
	    self.oldScope()
	    return result

        elif isinstance(ttype, CollectionType):
	    self.newScope()
            result = self.toReadCollection(value, ttype)
	    self.oldScope()
	    return result

        elif isinstance(ttype, EnumType):
	    return self.toReadPrimitive(value, PHP_TYPE_PROTOCOL_MAP[I32_TYPE])

        elif isinstance(ttype, TypedefType):
            return self.toRead(value, ttype.definitionType)

        else:
            raise Exception, "Unsupported type "+str(type(ttype))+":"+str(ttype)

    def toReadStruct(self, value, struct):

        nameVar = self.declare(STRING_TYPE, "name")
        fieldIdVar = self.declare(I16_TYPE, "fieldId")
        fieldTypeVar = self.declare(U32_TYPE, "fieldType")
	localVars = [nameVar, fieldTypeVar, fieldIdVar]

        result= string.join([self.toDeclaration(localVar) for localVar in localVars], "")

        result+= self.toReadStructBegin(nameVar)

        result+= self.indent()+"while(true) {\n"

        self.indent += 1

        result+= self.toReadFieldBegin(nameVar, fieldTypeVar, fieldIdVar) 

        result += self.indent()+"if("+fieldTypeVar.name+" == "+PHP_PROTOCOL_TSTOP+") {\n"

        self.indent+= 1

        result+= self.indent()+"break;\n"

        self.indent-= 1

        result+= self.indent()+"}\n"

        result+= self.indent()+"switch("+fieldIdVar.name+") {\n"

        self.indent+= 1

        # Sort field list in order of increasing ids

        fieldList = []

        fieldList+= struct.fieldList

        fieldList.sort(lambda a,b: a.id - b.id)

        for field in fieldList:
            if isVoidType(field.type):
                continue

            result+= self.indent()+"case "+str(field.id)+":\n"

            result+= self.toRead(value+"->"+field.name, field.type)
	    result+= self.indent()+"break;\n"

        result+= self.indent()+"default:\n"
        result+= self.toSkipField(fieldTypeVar)
        result+= self.indent()+"break;\n"

        self.indent-= 1

        result+= self.indent()+"}\n"

        self.indent-= 1

        result+= self.indent()+"}\n"

        result+= self.toReadStructEnd()

        result+= self.indent()+"return "+value+";\n"

        return result

    def toReadCollection(self, value, collection):

        isMap = isinstance(collection, MapType)

        sizeVar = self.declare(U32_TYPE, "size")
        valueTypeVar = self.declare(U32_TYPE, "valueType")
        elemVar = self.declare(collection.valueType, "elem")
        localVars = [sizeVar, valueTypeVar, elemVar]

        if isMap:
            keyTypeVar = self.declare(U32_TYPE, "keyType")
            key = self.declare(collection.keyType, "key")
            localVars+= [keyTypeVar, key]

        ix = self.declare(U32_TYPE, "ix")

        result= string.join([self.toDeclaration(localVar) for localVar in localVars], "")

        if isMap:
            result+= self.toReadMapBegin(keyTypeVar, valueTypeVar, sizeVar)
        elif isinstance(collection, ListType):
            result+= self.toReadListBegin(valueTypeVar, sizeVar)
        elif isinstance(collection, SetType):
            result+= self.toReadSetBegin(valueTypeVar, sizeVar)
	else:
	    raise Exception, "Unknown collection type "+str(collection)

        result+= self.indent()+"for("+ix.name+" = 0; "+ix.name+" < "+sizeVar.name+"; ++"+ix.name+") {\n"

        self.indent+= 1

	if isMap:
	    result+= self.toRead(key.name, collection.keyType)

	result+= self.toRead(elemVar.name, collection.valueType)
	
        if isMap:
            result+= self.indent()+value+"["+key.name+"] = "+elemVar.name+";\n"
        else:
            result+= self.indent()+value+"[] = "+elemVar.name+";\n"

	self.indent-= 1

	result+= self.indent()+"}\n"

        if isMap:
            result+= self.toReadMapEnd()
        elif isinstance(collection, ListType):
            result+= self.toReadListEnd()
        elif isinstance(collection, SetType):
            result+= self.toReadSetEnd()
	else:
	    raise Exception, "Unknown collection type "+str(collection)

	return result

class Writer(CodeGenerator):
    def __init__(self,
                 oprot="$this->_oprot",
                 otrans="$this->_otrans",
                 scope=Scope(),
		 indent=Indenter()):
	CodeGenerator.__init__(self, scope, indent)
        self.oprot = oprot
        self.otrans = otrans

    def toWriteMessageBegin(self, messageName, seqid):
        return self.indent()+self.oprot+"->writeMessageBegin("+self.otrans+", "+messageName+", "+seqid+");\n"

    def toWriteMessageEnd(self):
        return self.indent()+self.oprot+"->writeMessageEnd("+self.otrans+");\n"

    def toWriteStructBegin(self, structName):
        return self.indent()+self.oprot+"->writeStructBegin("+self.otrans+", "+structName+");\n"

    def toWriteStructEnd(self):
        return self.indent()+self.oprot+"->writeStructEnd("+self.otrans+");\n"

    def toWriteMapBegin(self, keyType, valueType, size):
        return self.indent()+self.oprot+"->writeMapBegin("+self.otrans+", "+keyType+", "+valueType+", "+size+");\n"

    def toWriteMapEnd(self):
        return self.indent()+self.oprot+"->writeMapEnd("+self.otrans+");\n"

    def toWriteSetBegin(self, valueType, size):
        return self.indent()+self.oprot+"->writeSetBegin("+self.otrans+", "+valueType+", "+size+");\n"

    def toWriteSetEnd(self):
        return self.indent()+self.oprot+"->writeSetEnd("+self.otrans+");\n"

    def toWriteListBegin(self, valueType, size):
        return self.indent()+self.oprot+"->writeListBegin("+self.otrans+", "+valueType+", "+size+");\n"

    def toWriteListEnd(self):
        return self.indent()+self.oprot+"->writeListEnd("+self.otrans+");\n"

    def toWriteFieldBegin(self, fieldName, fieldType, fieldId):
        return self.indent()+self.oprot+"->writeFieldBegin("+self.otrans+", "+fieldName+", "+fieldType+", "+str(fieldId)+");\n"

    def toWriteFieldEnd(self):
        return self.indent()+self.oprot+"->writeFieldEnd("+self.otrans+");\n"

    def toWriteFieldStop(self):
        return self.indent()+self.oprot+"->writeFieldStop("+self.otrans+");\n"

    def toSkipField(self, fieldType):
        return self.indent()+self.oprot+"->skipField("+self.otrans+", "+fieldType+");\n"

    def toWriteFlush(self):
	return self.indent()+self.otrans+"->flush();\n"

    def toWritePrimitive(self, value, suffix):
        return self.indent()+self.oprot+"->write"+suffix+"("+self.otrans+", "+value+");\n"

    def toWrite(self, value, ttype):

        if isinstance(ttype, PrimitiveType):
            return self.toWritePrimitive(value, PHP_TYPE_PROTOCOL_MAP[ttype])

        elif isinstance(ttype, StructType):
	    self.newScope()
            result = self.toWriteStruct(value, ttype)
	    self.oldScope()
	    return result

        elif isinstance(ttype, CollectionType):
	    self.newScope()
            result = self.toWriteCollection(value, ttype)
	    self.oldScope()
	    return result

        elif isinstance(ttype, EnumType):
	    return self.toWritePrimitive(value, PHP_TYPE_PROTOCOL_MAP[I32_TYPE])

        elif isinstance(ttype, TypedefType):
            return self.toWrite(value, ttype.definitionType)

        else:
            raise Exception, "Unsupported type "+str(type(ttype))+":"+str(ttype)

    def toWriteStruct(self, value, struct):

	result=self.indent()+"{\n"

	self.indent+= 1

        result+= self.toWriteStructBegin("\""+struct.name+"\"")

        for field in struct.fieldList:
            if isVoidType(field.type):
                continue

            result+= self.toWriteFieldBegin("\""+field.name+"\"", toWireType(field.type), field.id)
	    result+= self.toWrite(value+"->"+field.name,  field.type)
            result+= self.toWriteFieldEnd()

	result+= self.toWriteFieldStop()

	result+= self.toWriteStructEnd()

	self.indent-= 1

	result+= self.indent()+"}\n"

        return result

    def toWriteCollection(self, value, collection):

	result=self.indent()+"{\n"

	self.indent+= 1

	size = "count("+value+")"

        isMap = isinstance(collection, MapType)

        elemVar = self.declare(VOID_TYPE, "elem")

        if isMap:
	    keyVar = self.declare(VOID_TYPE, "key")
            result+= self.toWriteMapBegin(toWireType(collection.keyType), toWireType(collection.valueType), size)
        elif isinstance(collection, ListType):
            result+= self.toWriteListBegin(toWireType(collection.valueType), size)
        elif isinstance(collection, SetType):
            result+= self.toWriteSetBegin(toWireType(collection.valueType), size)
	else:
	    raise Exception, "Unknown collection type "+str(collection)

	if isMap:

	    result+= self.indent()+"forech("+value+" as "+keyVar.name+" => "+elemVar.name+") {\n"

	else:

	    result+= self.indent()+"forech("+value+" as "+elemVar.name+") {\n"
	    
        self.indent+= 1

	if isMap:
	    result+= self.toWrite(keyVar.name, collection.keyType)

	result+= self.toWrite(elemVar.name, collection.valueType)
	
	self.indent-= 1

	result+= self.indent()+"}\n"

        if isMap:
            result+= self.toWriteMapEnd()
        elif isinstance(collection, ListType):
            result+= self.toWriteListEnd()
        elif isinstance(collection, SetType):
            result+= self.toWriteSetEnd()
	else:
	    raise Exception, "Unknown collection type "+str(collection)

	self.indent-= 1

	result+= self.indent()+"}\n"

	return result

class ClientFunctionGenerator(CodeGenerator):
    def __init__(self,
		 scope=Scope(),
		 indent=Indenter()):
	CodeGenerator.__init__(self, scope, indent)
	self.reader = Reader(scope=scope, indent=indent)
	self.writer = Writer(scope=scope, indent=indent)

    def __call__(self, function):
	
	result= self.indent()+"public function "+function.name+"("+string.join(["$arg"+str(ix) for ix in  range(len(function.args()))], ", ")+") {\n"

	self.newScope()

	self.indent+= 1

	result+= self.writer.toWriteMessageBegin("\""+function.name+"\"", "$this->seqid")
	result+= self.indent()+"$this->_seqid++;\n"

	# Send the args struct 

	result+= self.indent()+"{\n"

	self.newScope()

	self.indent+= 1

	result+= self.writer.toWriteStructBegin("\""+function.argsStruct.name+"\"")

        for ix in range(len(function.argsStruct.fieldList)):
	    field = function.argsStruct.fieldList[ix]
            if isVoidType(field.type):
                continue

            result+= self.writer.toWriteFieldBegin("\""+field.name+"\"", toWireType(field.type), field.id)
	    result+= self.writer.toWrite("$arg"+str(ix),  field.type)
            result+= self.writer.toWriteFieldEnd()

	result+= self.writer.toWriteFieldStop()

	result+= self.writer.toWriteStructEnd()

	self.indent-= 1

	self.oldScope()

	result+= self.indent()+"}\n"

	result+= self.writer.toWriteMessageEnd()

	result+= self.writer.toWriteFlush();

	resultVar = self.declare(function.resultStruct, "result")
	nameVar = self.declare(function.resultStruct, "name")
	seqidVar = self.declare(function.resultStruct, "seqid")

	result+= self.toDeclaration(resultVar, True)
	result+= self.toDeclaration(nameVar)
	result+= self.toDeclaration(seqidVar)

	result+= self.reader.toReadMessageBegin(nameVar, seqidVar)

	result+= self.indent()+"{\n"

	self.newScope()

	self.indent+= 1

	result+= self.reader.toRead(resultVar.name, function.resultStruct)

	self.indent-= 1

	self.oldScope()

	result+= self.indent()+"}\n"

	self.indent-= 1

	self.oldScope()

	result+= self.reader.toReadMessageEnd()

	result+= self.indent()+"}\n"
	
	return result

class ClientServiceGenerator(CodeGenerator):
    def __init__(self,
		 scope=Scope(),
		 indent=Indenter()):
	CodeGenerator.__init__(self, scope, indent)
	self.functionGenerator =  ClientFunctionGenerator(scope, indent)

    def __call__(self, service):
	
	result= self.indent()+"class "+service.name+"Client extends "+service.name+"If {\n"

	self.indent+= 1

	result+= self.indent()+"private $_itrans = null;\n"
	result+= self.indent()+"private $_otrans = null;\n\n"

	result+= self.indent()+"private $_iprot = null;\n"
	result+= self.indent()+"private $_oprot = null;\n\n"
	result+= self.indent()+"private $_seqid = 0;\n\n"

	result+= self.indent()+"public function __construct() {\n"
	self.indent+= 1

	result+= self.indent()+"$argv = func_get_args();\n"
	result+= self.indent()+"$argc = count($argv);\n"
	result+= self.indent()+"if ($argc == 2) {;\n"
	self.indent+= 1
	result+= self.indent()+"$this->_itrans = $this->_otrans = $argv[0];\n"
	result+= self.indent()+"$this->_iprot = $this->_oprot = $argv[1];\n"
	self.indent-= 1
	result+= self.indent()+"} else if($argc == 4) {\n"
	self.indent+= 1
	result+= self.indent()+"$this->_itrans = $argv[0];\n"
	result+= self.indent()+"$this->_otrans = $argv[1];\n"
	result+= self.indent()+"$this->_iprot = $argv[2];\n"
	result+= self.indent()+"$this->_oprot = $argv[3];\n"
	self.indent-= 1
	result+= self.indent()+"}\n"
	self.indent-= 1
	result+= self.indent()+"}\n\n"

	for function in service.functionList:

	    result+= self.functionGenerator(function)
	
	self.indent-= 1
	result+= self.indent()+"}\n"

	return result

PHP_PRIMITIVE_DEFAULT_MAP = {
    VOID_TYPE : "",
    BOOL_TYPE : "False",
    STRING_TYPE: "\'\'",
    UTF7_TYPE: "\'\'",
    UTF8_TYPE: "\'\'",
    UTF16_TYPE: "\'\'",
    BYTE_TYPE : "0",
    I08_TYPE: "0",
    I16_TYPE: "0",
    I32_TYPE: "0",
    I64_TYPE: "0",
    U08_TYPE: "0",
    U16_TYPE: "0",
    U32_TYPE: "0",
    U64_TYPE: "0",
    FLOAT_TYPE: "0.0",
    DOUBLE_TYPE: "0.0"
}

def toPHPNamespacePrefix(namespace):
    """No namespaces in PHP"""
    return ""

def toPHPNamespaceSuffix(namespace):
    """No namespaces in PHP"""
    return ""

def defaultValueForType(ttype, value=None):
    """Returns the default literal value for a given type"""

    if value:
	return value
    elif isinstance(ttype, PrimitiveType):
        return PHP_PRIMITIVE_DEFAULT_MAP[ttype]
    elif isinstance(ttype, CollectionType):
        return "array()"
    elif isinstance(ttype, StructType):
        return "null"
    elif isinstance(ttype, EnumType):
        return "0"
    elif isinstance(ttype, TypedefType):
        return defaultValueForType(toCanonicalType(ttype))
    else:
        raise Exception, "Unknown type "+str(ttype)

def newInstanceForType(ttype, value=None):
    """Returns the default new instance for a given type"""

    if value:
	return value
    elif isinstance(ttype, StructType):
        return "new "+ttype.name+"()"
    else:
	return defaultValueForType(ttype, value)

def toPHPTypeDeclaration(ttype):
    """ Converts the thrift IDL type to the corresponding PHP type.  Note that if ttype is FieldType, this function 
converts to type declaration followed by field name, i.e. \"string string_thing\""""

    if isinstance(ttype, Field):
        return "$"+ttype.name
    if isinstance(ttype, Function):
        return ttype.name+"("+string.join([toPHPTypeDeclaration(arg) for arg in ttype.args()], ", ")+")"
    else:
        return ""

def toTypedefDefinition(typedef):
    """Converts a thrift typedef to a PHP typdef definition."""

    return ""

def toEnumDefinition(enum):
    """ Converts a thrift enum to a PHP enum """

    result = "$GLOBALS[\'E_"+enum.name+"\'] = array(\n"

    result += string.join(["    \'"+ed.name+"\' => "+str(ed.id)+",\n" for ed in  enum.enumDefs], "")

    result+= ");\n\n"

    result += "final class "+enum.name+" {\n"

    result += string.join(["    const "+ed.name+" = "+str(ed.id)+";\n" for ed in  enum.enumDefs], "")

    result += "}\n"

    return result

def toStructDefinition(struct):
    """Converts a thrift struct to a PHP class"""

    result = "class "+struct.name+" {\n"

    # Create constructor defaults for primitive types

    # Field declarations

    result+= string.join(["    public $"+field.name+" = "+defaultValueForType(field.type)+";\n" for field in struct.fieldList if not isVoidType(field.type)], "")

    # bring it on home

    result+= "}\n"

    return result

PHP_DEFINITION_MAP = {
    TypedefType : toTypedefDefinition,
    EnumType : toEnumDefinition,
    StructType : toStructDefinition,
    ExceptionType : toStructDefinition,
    Service : None
    }
    
def toDefinitions(definitions):
    """Converts an arbitrary thrift grammatical unit definition to the corresponding PHP definition"""

    result = ""

    for definition in definitions:

        writer = PHP_DEFINITION_MAP[type(definition)]

        if writer:
            result+= writer(definition)+"\n"

    return result

PHP_THRIFT_NS = "facebook::thrift"

PHP_INTERFACE_FUNCTION_DECLARATION = Template("""    public abstract function ${functionDeclaration};
""")

PHP_INTERFACE_DECLARATION = Template("""
abstract class ${service}If {
${functionDeclarations}};
""")

def toServiceInterfaceDeclaration(service, debugp=None):
    """Converts a thrift service definition into a C++ abstract base class"""

    functionDeclarations = string.join([PHP_INTERFACE_FUNCTION_DECLARATION.substitute(service=service.name, functionDeclaration=toPHPTypeDeclaration(function)) for function in service.functionList], "")

    return PHP_INTERFACE_DECLARATION.substitute(service=service.name, functionDeclarations=functionDeclarations)

PHP_EXCEPTION = PHP_THRIFT_NS+"::Exception"

PHP_SP = Template("boost::shared_ptr<${klass}> ")


PHP_PROTOCOL_TSTOP = "TType::STOP"
PHP_PROTOCOL_TTYPE = "TType::"
PHP_PROTOCOL_CALL = "TMessageType::T_CALL"
PHP_PROTOCOL_REPLY = "TMessageType::T_REPLY"

PHP_TTYPE_MAP = {
    STOP_TYPE : PHP_PROTOCOL_TTYPE+"STOP",
    VOID_TYPE : PHP_PROTOCOL_TTYPE+"VOID",
    BOOL_TYPE : PHP_PROTOCOL_TTYPE+"BOOL",
    UTF7_TYPE : PHP_PROTOCOL_TTYPE+"UTF7",
    UTF7_TYPE : PHP_PROTOCOL_TTYPE+"UTF7",
    UTF8_TYPE : PHP_PROTOCOL_TTYPE+"UTF8",
    UTF16_TYPE : PHP_PROTOCOL_TTYPE+"UTF16",
    U08_TYPE : PHP_PROTOCOL_TTYPE+"U08",
    I08_TYPE : PHP_PROTOCOL_TTYPE+"I08",
    I16_TYPE : PHP_PROTOCOL_TTYPE+"I16",
    I32_TYPE : PHP_PROTOCOL_TTYPE+"I32",
    I64_TYPE : PHP_PROTOCOL_TTYPE+"I64",
    U08_TYPE : PHP_PROTOCOL_TTYPE+"U08",
    U16_TYPE : PHP_PROTOCOL_TTYPE+"U16",
    U32_TYPE : PHP_PROTOCOL_TTYPE+"U32",
    U64_TYPE : PHP_PROTOCOL_TTYPE+"U64",
    FLOAT_TYPE : PHP_PROTOCOL_TTYPE+"FLOAT",
    DOUBLE_TYPE : PHP_PROTOCOL_TTYPE+"DOUBLE",
    StructType : PHP_PROTOCOL_TTYPE+"STRUCT",
    ExceptionType : PHP_PROTOCOL_TTYPE+"STRUCT",
    ListType : PHP_PROTOCOL_TTYPE+"LIST",
    MapType : PHP_PROTOCOL_TTYPE+"MAP",
    SetType : PHP_PROTOCOL_TTYPE+"SET"
}


def toWireType(ttype):
    """Converts a thrift type to the corresponding wire type.   This differs from toPHPTypeDeclaration in that it reduces typedefs
to their canonical form and converts enums to signedf 32 bit integers"""

    if isinstance(ttype, PrimitiveType):
	return PHP_TTYPE_MAP[ttype]

    elif isinstance(ttype, EnumType):
	return PHP_TTYPE_MAP[I32_TYPE]

    elif isinstance(ttype, TypedefType):
	return toWireType(toCanonicalType(ttype))

    elif isinstance(ttype, StructType) or isinstance(ttype, CollectionType):
	return PHP_TTYPE_MAP[type(ttype)]

    else:
	raise Exception, "No wire type for thrift type: "+str(ttype)

def toGenDir(filename, suffix="php-gen", debugp=None):
    """creates a generated-code subdirectory for C++ code based on filename of thrift source file and optional suffix"""

    result = os.path.join(os.path.split(filename)[0], suffix)

    if not os.path.exists(result):
        os.mkdir(result)

    return result

def toBasename(filename, debugp=None):
    """ Take the filename minus the path and\".thrift\" extension  if present """

    basename = os.path.split(filename)[1]

    tokens = os.path.splitext(basename)

    if tokens[1].lower() == ".thrift":
        basename = tokens[0]

    if debugp:
        debugp("toBasename("+str(filename)+") => "+str(basename))

    return basename

def toDefinitionHeaderName(filename, genDir=None, debugp=None):
    """Creates a file name for the public thrift data types based on filename of thrift source file and optional suffix"""

    if not genDir:
        genDir = toGenDir(filename)

    basename = toBasename(filename)

    result = os.path.join(genDir, basename+"_types.php")

    if debugp:
        debugp("toDefinitionHeaderName("+str(filename)+", "+str(genDir)+") => "+str(basename))

    return result

def writeDefinitionHeader(program, filename, genDir=None, debugp=None):
    """Writes public thrift data types defined in program into a public data types header file.  Uses the name of the original
thrift source, filename, and the optional generated C++ code directory, genDir, to determine the name and location of header file"""

    definitionHeader = toDefinitionHeaderName(filename, genDir)

    if debugp:
        debugp("definitionHeader: "+str(definitionHeader))

    phpFile = file(definitionHeader, "w")

    basename = toBasename(filename)

    phpFile.write(PHP_TYPES_HEADER.substitute(source=basename, date=time.ctime(), namespacePrefix=toPHPNamespacePrefix(program.namespace)))

    phpFile.write(toDefinitions(program.definitions))

    phpFile.write(PHP_TYPES_FOOTER.substitute(source=basename, namespaceSuffix=toPHPNamespaceSuffix(program.namespace)))

    phpFile.close()

def toToImplementationSourceName(filename, genDir=None, debugp=None):
    """Creates a file name for the public thrift data types based on filename of thrift source file and optional suffix"""

    if not genDir:
        genDir = toGenDir(filename)

    basename = toBasename(filename)

    result = os.path.join(genDir, basename+".php")

    if debugp:
        debugp("toToImplementationSourceName("+str(filename)+", "+str(genDir)+") => "+str(basename))

    return result

def writeImplementationSource(program, filename, genDir=None, debugp=None):
    """Writes public thrift service interface, client stubs, and private types defined in a thrift program into a php library file.  Uses the name of the original
thrift source, filename, and the optional generated C++ code directory, genDir, to determine the name and location of header file"""

    toImplementationSource = toToImplementationSourceName(filename, genDir)

    if debugp:
        debugp("toImplementationSource: "+str(toImplementationSource))

    phpFile = file(toImplementationSource, "w")

    basename = toBasename(filename)

    phpFile.write(PHP_SERVICES_HEADER.substitute(source=basename, date=time.ctime(), namespacePrefix=toPHPNamespacePrefix(program.namespace)))

    # Generate classes for function result "structs"

    privateStructs = []

    for service in program.serviceMap.values():
	
	phpFile.write(toServiceInterfaceDeclaration(service))

	for function in service.functionList:
	    privateStructs.append(function.resultStruct)

    phpFile.write(toDefinitions(privateStructs))    

    serviceGenerator = ClientServiceGenerator()

    for service in program.serviceMap.values():

	phpFile.write(serviceGenerator(service))
	
    phpFile.write(PHP_SERVICES_FOOTER.substitute(source=basename, namespaceSuffix=toPHPNamespaceSuffix(program.namespace)))

    phpFile.close()

class PHPGenerator(Generator):

    def __call__(self, program, filename, genDir=None, debugp=None):

        writeDefinitionHeader(program, filename, genDir, debugp)
        
        writeImplementationSource(program, filename, genDir, debugp)