page = $page; return $this; } /** * Returns current page number. */ public function getPage(): int { return $this->base + $this->getPageIndex(); } /** * Returns first page number. */ public function getFirstPage(): int { return $this->base; } /** * Returns last page number. */ public function getLastPage(): ?int { return $this->itemCount === null ? null : $this->base + max(0, $this->getPageCount() - 1); } /** * Returns the sequence number of the first element on the page */ public function getFirstItemOnPage(): int { return $this->itemCount !== 0 ? $this->offset + 1 : 0; } /** * Returns the sequence number of the last element on the page */ public function getLastItemOnPage(): int { return $this->offset + $this->length; } /** * Sets first page (base) number. */ public function setBase(int $base): static { $this->base = $base; return $this; } /** * Returns first page (base) number. */ public function getBase(): int { return $this->base; } /** * Returns zero-based page number. */ protected function getPageIndex(): int { $index = max(0, $this->page - $this->base); return $this->itemCount === null ? $index : min($index, max(0, $this->getPageCount() - 1)); } /** * Is the current page the first one? */ public function isFirst(): bool { return $this->getPageIndex() === 0; } /** * Is the current page the last one? */ public function isLast(): bool { return $this->itemCount === null ? false : $this->getPageIndex() >= $this->getPageCount() - 1; } /** * Returns the total number of pages. */ public function getPageCount(): ?int { return $this->itemCount === null ? null : (int) ceil($this->itemCount / $this->itemsPerPage); } /** * Sets the number of items to display on a single page. */ public function setItemsPerPage(int $itemsPerPage): static { $this->itemsPerPage = max(1, $itemsPerPage); return $this; } /** * Returns the number of items to display on a single page. */ public function getItemsPerPage(): int { return $this->itemsPerPage; } /** * Sets the total number of items. */ public function setItemCount(?int $itemCount = null): static { $this->itemCount = $itemCount === null ? null : max(0, $itemCount); return $this; } /** * Returns the total number of items. */ public function getItemCount(): ?int { return $this->itemCount; } /** * Returns the absolute index of the first item on current page. */ public function getOffset(): int { return $this->getPageIndex() * $this->itemsPerPage; } /** * Returns the absolute index of the first item on current page in countdown paging. */ public function getCountdownOffset(): ?int { return $this->itemCount === null ? null : max(0, $this->itemCount - ($this->getPageIndex() + 1) * $this->itemsPerPage); } /** * Returns the number of items on current page. */ public function getLength(): int { return $this->itemCount === null ? $this->itemsPerPage : min($this->itemsPerPage, $this->itemCount - $this->getPageIndex() * $this->itemsPerPage); } }