const fs = require( "node:fs/promises" );
const path = require( "path" );
const { loadJSON, getFiles, saveUTF8, getMatches, loadUTF8, insertText, isDirectory } = require( "./library.js" ); 
const { CppClassMember } = require( "./cpp-class-member.js" ); 

function createCppHeader( className, extendingClassName, headerDefine, protectedMembers, 
                          publicMembers, includes )
{

let cppHeader = 

`
/* ${className}.h */

#ifndef ${headerDefine}
#define ${headerDefine}

${includes}


class ${className} : public ${extendingClassName} 
{
  GDCLASS(${className}, ${extendingClassName});

protected:
  static void _bind_methods();
  ${protectedMembers}

public:

  ${publicMembers}

  ${className}();
 
  ~${className}();
};


#endif // ${headerDefine}
`

return cppHeader;


}

function createCppImplementation( className, boundMethods, constructorExpressions, destructorExpressions, methodImplementations )
{

let cppImplementation = 
`
/* ${className}.cpp */

#include "${className}.h"


void ${className}::_bind_methods() 
{
  ${boundMethods}
}

${className}::${className}() 
{
  ${constructorExpressions}
}

${className}::~${className}()
{
  ${destructorExpressions}
}

${methodImplementations}

`

return cppImplementation;

}

let definitionsPath = __dirname + "/rokojori-action-library-definitions";
let outputPath = __dirname + "/rokojori-action-library";
let registerTypesPath = outputPath + "/register_types.cpp";
let classRegistrationRegex = /ClassDB\:\:register_class\<(\w+)\>\(\)\;/;

function createTypeRegistration( className )
{
  return `ClassDB::register_class<${className}>();`;
}

function createIncludes( className )
{
  console.log( "Create include", className );

  let godotClasses = 
  {
    "Node" : "scene/main/node.h",
    "Node2D" : "scene/2d/node_2d.h",
    "Node3D" : "scene/3d/node_3d.h",
    "Resource" : "core/io/resource.h"    
  }

  if ( godotClasses[ className ] )
  {
    return `#include "${godotClasses[ className ]}"`; 
  }
  

  return `#include "./${className}.h"`;
}

async function main()
{
  let files = await getFiles( definitionsPath );
  files = files.filter( f => ! f.startsWith( "_" ) );
  
  let typesFile = await loadUTF8( registerTypesPath );

  let types = getRegistratedTypes( typesFile );

  let missingTypes = [];

  for ( let file of files )
  {
    await createCppFiles( path.join( definitionsPath, file ), types, missingTypes );
  }

  if ( missingTypes.length === 0 )
  {
    return;
  }
  
  console.log( "Registrating missing types:", missingTypes );

  let additions = missingTypes.map( mt => createTypeRegistration( mt ) );
  let additionsBlock = additions.join( "\n  " );

  

  

  
  let lastType = types[ types.length -1 ];
  let insertPosition =  lastType.index + lastType.match.length;
  let updatedTypesFile = insertText( typesFile, "\n  " + additionsBlock, insertPosition );


  let includeMatches = getMatches( updatedTypesFile, /#include "(\w|\.|\/|\\)+.h"/ );
  let lastInclude = includeMatches[ includeMatches.length - 1 ];
  let includes = missingTypes.map( mt => createIncludes( mt ) ).join( "\n" );
  insertPosition =  lastInclude.index + lastInclude.match.length;
  updatedTypesFile = insertText( updatedTypesFile, "\n" + includes, insertPosition );

  saveUTF8( registerTypesPath, updatedTypesFile );

}



function grabMembers( membersData, accessModifier )
{
  let members = [];

  if ( ! membersData )
  {
    return members;
  }

  for ( let it in membersData )
  {
    if ( ! membersData.hasOwnProperty( it ) )
    {
      continue;
    }

    let nameDefinition = it;    
    let memberData = membersData[ it ];

    let actionRegex = /^\s*action\s+(\w+)\s*$/;

    if ( actionRegex.test( nameDefinition ) )
    {
      let name = actionRegex.exec( nameDefinition )[ 1 ];
      let upperCaseName = name[ 0 ].toUpperCase() + name.substring( 1 );
      let actionName = `on${upperCaseName}`;

      let signal = `signal ${name}()`;
      let actionGetter = `virtual get_${actionName}():Ref<RJAction>`;
      let actionSetter = `virtual set_${actionName}()`;

      members.push( new CppClassMember( accessModifier, signal, {} ) );
      members.push( new CppClassMember( "protected", "m_" + name, {} ) );
      members.push( new CppClassMember( accessModifier, actionGetter, {} ) );
      members.push( new CppClassMember( accessModifier, actionSetter, { "action":"Ref<RJAction>"} ) );
    }
    else
    {
      let classMember = new CppClassMember( accessModifier, nameDefinition, memberData );
      members.push( classMember );
    }


  }

  return members;
}

function getHeaderDefine( className )
{
  className = className.replace( /^RJ/, "" );

  let output = [ className[ 0 ] ];

  for ( let i = 1; i < className.length; i++ )
  {
    let character = className[ i ];
    let upperCaseCharacter = character.toUpperCase();
    
    if ( character === upperCaseCharacter )
    {
      output.push( "_" );
      
    }

    output.push( upperCaseCharacter );

  } 

  className = output.join( "" );

  return "ROKOJORI__" + className + "_H";
}

function getRegistratedTypes( text )
{
  let matches = getMatches( text, classRegistrationRegex );

  let types = matches.map(
    m => 
    { 
      return { match: m.match, index: m.index, type: classRegistrationRegex.exec( m.match )[ 1 ] }
    }
  );

  return types;

}



async function createCppFiles( definitionPath, types, missingTypes )
{
  console.log( "Creating: ", definitionPath );

  let jsonPath = definitionPath;
  // path.join( definitionsPath, definitionPath );

  let isDir = await isDirectory( jsonPath );

  if ( isDir )
  {
    let files = await getFiles( jsonPath );

    for ( let file of files )
    {
      await createCppFiles( path.join( jsonPath, file ), types, missingTypes );
    }

    return Promise.resolve();
  }

  let data = await loadJSON( jsonPath );

  //console.log( "data:", jsonPath, data );

  let classNameResult = /(\w+)(?:\:(\w+))?/.exec( data.class );

  let className      = classNameResult[ 1 ];
  let extendingClass = classNameResult[ 2 ];

  let headerDefine =  getHeaderDefine( className );
  
  let fromProtectedMembers = grabMembers( data.protected, "protected" );  
  let fromPublicMembers    = grabMembers( data.public, "public" );

  let protectedMembers = [];
  let publicMembers = [];

  let insertMember = m => 
  { 
    let container = m.accessModifier === "public" ? publicMembers : protectedMembers;
    container.push( m );
  };

  fromProtectedMembers.forEach( m => insertMember( m ) );
  fromPublicMembers.forEach( m => insertMember( m ) );


  let allMembers = [].concat( protectedMembers ).concat( publicMembers );


  let protectedHeader     = protectedMembers.map( m => m.getHeaderDefinition() ).join( "\n  " );
  let publicHeader        = publicMembers.map( m => m.getHeaderDefinition() ).join( "\n  " );

  let properties          = publicMembers.filter( m => ! m.isMethod );

  let propertyDefinitions = properties.map( p => p.getPropertyHeaderDefinition() ).join( "\n  " );
  
  protectedHeader += "\n\n  " + propertyDefinitions; 

  let methodBindings =  allMembers.map( m => m.getMethodBinding( className ) ).join( "\n  " );
  
  let initializers = allMembers.filter( m => m.isMemberWithInitialValue ).map( m => m.getMemberInitializer() ).join( "\n  ");

  let includes = "";

  if ( data.includes )
  {
    includes = data.includes.map( inc => `#include "${inc}"` );
  }

  let extendingClassInclude = createIncludes( extendingClass );

  includes += "\n" + extendingClassInclude;
  let header = createCppHeader( className, extendingClass, headerDefine, protectedHeader, publicHeader, includes );
  
  let constructorExpressions = initializers;
  let destructorExpressions = "";
  let methodImplementations = "";

  let propertyImplementations = properties.map( p => p.getPropertyImplementation( className ) ).join( "\n" );

  methodImplementations += propertyImplementations;

  let implementation = createCppImplementation( className, methodBindings, constructorExpressions, destructorExpressions, methodImplementations );

  //console.log( header );
  //console.log( implementation );

  let hasType = types.find( t => t.type === className );

  if ( ! hasType )
  {
    missingTypes.push( className );
  }

  let rawFilePath = path.join( outputPath, className );
  await saveUTF8( rawFilePath + ".h", header );
  await saveUTF8( rawFilePath + ".cpp", implementation ); 

  return Promise.resolve();
}



main();