<?hh // strict

namespace Facebook\HackCodegen;

/**

* For a given ModelSchema, this class generates code for a class

* that will allow to insert rows in a database.

*/

class ModelMutatorGenerator {

public function __construct(

private \ModelSchema $schema,

) {}

private function getName(): string {

$ref = new \ReflectionClass($this->schema);

$name = $ref->getShortName();

$remove_schema = Str::endsWith($name, 'Schema')

? Str::substr($name, 0, -6)

: $name;

return $remove_schema.'Mutator';

}

public function generate(): void {

$name = $this->getName();

$class = codegen_class($name)

->setIsFinal()

->addVar($this->getDataVar())

->setConstructor($this->getConstructor())

->addMethod($this->getCreateMethod())

->addMethod($this->getUpdateMethod())

->addMethod($this->getDeleteMethod())

->addMethod($this->getSaveMethod())

->addMethod($this->getCheckRequiredFieldsMethod())

->addMethods($this->getSetters())

->setHasManualMethodSection();

codegen_file(dirname(__FILE__).'/../models/'.$name.'.php')

->addClass($class)

->setIsStrict(true)

->save();

}

private function getDataVar(): CodegenMemberVar {

return codegen_member_var('data')

->setType('Map<string, mixed>')

->setValue(Map {});

}

private function getConstructor(): CodegenConstructor {

return codegen_constructor()

->addParameter('private ?int $id = null')

->setPrivate();

}

private function getCreateMethod(): CodegenMethod {

return codegen_method('create')

->setReturnType('this')

->setIsStatic()

->setBody(

hack_builder()

->addReturn('new %s()', $this->getName())

->getCode()

);

}

private function getUpdateMethod(): CodegenMethod {

return codegen_method('update')

->addParameter('int $id')

->setReturnType('this')

->setIsStatic()

->setBody(

hack_builder()

->addReturn('new %s($id)', $this->getName())

->getCode()

);

}

private function getDeleteMethod(): CodegenMethod {

return codegen_method('delete')

->addParameter('int $id')

->setReturnType('void')

->setIsStatic()

->setBody(

hack_builder()

->addLine(

'DB::delete("%s", "%s=%%s", $id);',

$this->schema->getTableName(),

$this->schema->getIdField()

)

->getCode()

);

}

private function getSaveMethod(): CodegenMethod {

$body = hack_builder()

->addAssignment('$id', '$this->id')

->startIfBlock('$id === null')

->addLine('$this->checkRequiredFields();')

->addLine(

'DB::insert("%s", $this->data->toArray());',

$this->schema->getTableName()

)

->addReturn('(int) DB::insertId()')

->addElseBlock()

->addLine(

'DB::update("%s", $this->data->toArray(), "%s=%%s", $this->id);',

$this->schema->getTableName(),

$this->schema->getIdField()

)

->addReturn('$id')

->endIfBlock();

return codegen_method('save')

->setReturnType('int')

->setBody($body->getCode());

}

private function getCheckRequiredFieldsMethod(): CodegenMethod {

$required = $this->schema->getFields()

->filter($field ==> !$field->isOptional())

->map($field ==> $field->getDbColumn())

->values()->toSet();

$body = hack_builder()

->add('$required = ')

->addSet($required)

->closeStatement()

->addAssignment(

'$missing',

'$required->removeAll($this->data->keys());'

)

->addMultilineCall(

'invariant',

Vector {

'$missing->isEmpty()',

'"The following required fields are missing: "'.

'.implode(", ", $missing)',

}

);

return codegen_method('checkRequiredFields')

->setReturnType('void')

->setBody($body->getCode());

}

private function getSetters(): Vector<CodegenMethod> {

$methods = Vector {};

foreach($this->schema->getFields() as $name => $field) {

if ($field->getType() === 'DateTime') {

$value = '$value->format("Y-m-d")';

} else {

$value = '$value';

}

$body = hack_builder();

if ($field->isManual()) {

$body->beginManualSection($name);

}

$body

->addLine('$this->data["%s"] = %s;', $field->getDbColumn(), $value);

if ($field->isManual()) {

$body->endManualSection();

}

$body->addReturn('$this');

$methods[] = codegen_method('set'.$name)

->setReturnType('this')

->addParameter($field->getType().' $value')

->setBody($body->getCode());

}

return $methods;

}

}