<?php

namespace RoosterLMS\Data;

defined( 'ABSPATH' ) || exit;

final class SqlPart {

	private string $text;

	private array $args;

	public function __construct( string $text = '', ...$args ) {
		$this->text = $text;
		$this->args = self::flat( $args );
	}

	public static function of( string $text, ...$args ): self {
		return new self( $text, ...$args );
	}

	public function add( string|SqlPart $text, ...$args ): self {
		if ( $text instanceof self ) {
			return new self( $this->text . $text->text, ...array_merge( $this->args, $text->args ) );
		}
		return new self( $this->text . $text, ...array_merge( $this->args, self::flat( $args ) ) );
	}

	public static function join( string $glue, array $parts ): self {
		$text = array();
		$args = array();
		foreach ( $parts as $part ) {
			$part = is_string( $part ) ? new self( $part ) : $part;
			if ( ! $part instanceof self || '' === $part->text ) {
				continue;
			}
			$text[] = $part->text;
			$args   = array_merge( $args, $part->args );
		}
		return new self( implode( $glue, $text ), ...$args );
	}

	public static function and_in( string $column, array $ids ): self {
		$ids = array_values( array_map( 'intval', $ids ) );
		if ( array() === $ids ) {
			return new self();
		}
		$parts = explode( '.', $column, 2 );
		$ident = 2 === count( $parts ) ? '%i.%i' : '%i';
		$marks = 1 === count( $ids ) ? ' = %d' : ' IN (' . implode( ',', array_fill( 0, count( $ids ), '%d' ) ) . ')';
		return new self( ' AND ' . $ident . $marks, ...array_merge( $parts, $ids ) );
	}

	public static function in_list( array $values, string $mark = '%d' ): self {
		$values = array_values( $values );
		$mark   = '%s' === $mark ? '%s' : '%d';
		return new self( implode( ',', array_fill( 0, count( $values ), $mark ) ), ...$values );
	}

	public function strip_prefix( string $prefix ): self {
		return '' !== $prefix && str_starts_with( $this->text, $prefix ) ? new self( substr( $this->text, strlen( $prefix ) ), ...$this->args ) : $this;
	}

	public function text(): string {
		return $this->text;
	}

	public function args(): array {
		return $this->args;
	}

	public function is_empty(): bool {
		return '' === $this->text;
	}

	private static function flat( array $args ): array {
		return 1 === count( $args ) && is_array( $args[0] ) ? array_values( $args[0] ) : array_values( $args );
	}
}