<?php
/**
* @package dompdf
* @link https://github.com/dompdf/dompdf
* @license http://www.gnu.org/copyleft/lesser.html GNU Lesser General Public License
*/
namespace Dompdf\FrameReflower;

use Dompdf\Helpers;
use Dompdf\FrameDecorator\Block as BlockFrameDecorator;
use Dompdf\FrameDecorator\Image as ImageFrameDecorator;

/**
* Image reflower class
*
* @package dompdf
*/
class Image extends AbstractFrameReflower
{

/**
* Image constructor.
* @param ImageFrameDecorator $frame
*/
function __construct(ImageFrameDecorator $frame)
{
parent::__construct($frame);
}

/**
* @param BlockFrameDecorator|null $block
*/
function reflow(?BlockFrameDecorator $block = null)
{
$this->determine_absolute_containing_block();

// Counters and generated content
$this->_set_content();

//FLOAT
//$frame = $this->_frame;
//$page = $frame->get_root();

//if ($frame->get_style()->float !== "none" ) {
// $page->add_floating_frame($this);
//}

$this->resolve_dimensions();
$this->resolve_margins();

$frame = $this->_frame;
$frame->position();

if ($block && $frame->is_in_flow()) {
$block->add_frame_to_line($frame);
}
}

public function get_min_max_content_width(): array
{
// TODO: While the containing block is not set yet on the frame, it can
// already be determined in some cases due to fixed dimensions on the
// ancestor forming the containing block. In such cases, percentage
// values could be resolved here
$style = $this->_frame->get_style();

[$width] = $this->calculate_size(null, null);
$min_width = $this->resolve_min_width(null);
$percent_width = Helpers::is_percent($style->width)
|| Helpers::is_percent($style->max_width)
|| ($style->width === "auto"
&& (Helpers::is_percent($style->height) || Helpers::is_percent($style->max_height)));

// Use the specified min width as minimum when width or max width depend
// on the containing block and cannot be resolved yet. This mimics
// browser behavior
$min = $percent_width ? $min_width : $width;
$max = $width;

return [$min, $max];
}

/**
* Calculate width and height, accounting for min/max constraints.
*
* * https://www.w3.org/TR/CSS21/visudet.html#inline-replaced-width
* * https://www.w3.org/TR/CSS21/visudet.html#inline-replaced-height
* * https://www.w3.org/TR/CSS21/visudet.html#min-max-widths
* * https://www.w3.org/TR/CSS21/visudet.html#min-max-heights
*
* @param float|null $cbw Width of the containing block.
* @param float|null $cbh Height of the containing block.
*
* @return float[]
*/
protected function calculate_size(?float $cbw, ?float $cbh): array
{
/** @var ImageFrameDecorator */
$frame = $this->_frame;
$style = $frame->get_style();

$computed_width = $style->width;
$computed_height = $style->height;

$width = $cbw === null && Helpers::is_percent($computed_width)
? "auto"
: $style->length_in_pt($computed_width, $cbw ?? 0);
$height = $cbh === null && Helpers::is_percent($computed_height)
? "auto"
: $style->length_in_pt($computed_height, $cbh ?? 0);
$min_width = $this->resolve_min_width($cbw);
$max_width = $this->resolve_max_width($cbw);
$min_height = $this->resolve_min_height($cbh);
$max_height = $this->resolve_max_height($cbh);

if ($width === "auto" && $height === "auto") {
// Use intrinsic dimensions, resampled to pt
[$img_width, $img_height] = $frame->get_intrinsic_dimensions();
$w = $frame->resample($img_width);
$h = $frame->resample($img_height);

// Resolve min/max constraints according to the constraint-violation
// table in https://www.w3.org/TR/CSS21/visudet.html#min-max-widths
$max_width = max($min_width, $max_width);
$max_height = max($min_height, $max_height);

if (($w > $max_width && $h <= $max_height)
|| ($w > $max_width && $h > $max_height && $max_width / $w <= $max_height / $h)
|| ($w < $min_width && $h > $min_height)
|| ($w < $min_width && $h < $min_height && $min_width / $w > $min_height / $h)
) {
$width = Helpers::clamp($w, $min_width, $max_width);
$height = $width * ($img_height / $img_width);
$height = Helpers::clamp($height, $min_height, $max_height);
} else {
$height = Helpers::clamp($h, $min_height, $max_height);
$width = $height * ($img_width / $img_height);
$width = Helpers::clamp($width, $min_width, $max_width);
}
} elseif ($height === "auto") {
// Width is fixed, scale height according to aspect ratio
[$img_width, $img_height] = $frame->get_intrinsic_dimensions();
$width = Helpers::clamp((float) $width, $min_width, $max_width);
$height = $width * ($img_height / $img_width);
$height = Helpers::clamp($height, $min_height, $max_height);
} elseif ($width === "auto") {
// Height is fixed, scale width according to aspect ratio
[$img_width, $img_height] = $frame->get_intrinsic_dimensions();
$height = Helpers::clamp((float) $height, $min_height, $max_height);
$width = $height * ($img_width / $img_height);
$width = Helpers::clamp($width, $min_width, $max_width);
} else {
// Width and height are fixed
$width = Helpers::clamp((float) $width, $min_width, $max_width);
$height = Helpers::clamp((float) $height, $min_height, $max_height);
}

return [$width, $height];
}

protected function resolve_dimensions(): void
{
/** @var ImageFrameDecorator */
$frame = $this->_frame;
$style = $frame->get_style();

$debug_png = $this->get_dompdf()->getOptions()->getDebugPng();

if ($debug_png) {
[$img_width, $img_height] = $frame->get_intrinsic_dimensions();
print "resolve_dimensions() " .
$frame->get_style()->width . " " .
$frame->get_style()->height . ";" .
$frame->get_parent()->get_style()->width . " " .
$frame->get_parent()->get_style()->height . ";" .
$frame->get_parent()->get_parent()->get_style()->width . " " .
$frame->get_parent()->get_parent()->get_style()->height . ";" .
$img_width . " " .
$img_height . "|";
}

[, , $cbw, $cbh] = $frame->get_containing_block();
[$width, $height] = $this->calculate_size($cbw, $cbh);

if ($debug_png) {
print $width . " " . $height . ";";
}

$style->set_used("width", $width);
$style->set_used("height", $height);
}

protected function resolve_margins(): void
{
// Only handle the inline case for now
// https://www.w3.org/TR/CSS21/visudet.html#inline-replaced-width
// https://www.w3.org/TR/CSS21/visudet.html#inline-replaced-height
$style = $this->_frame->get_style();

if ($style->margin_left === "auto") {
$style->set_used("margin_left", 0.0);
}
if ($style->margin_right === "auto") {
$style->set_used("margin_right", 0.0);
}
if ($style->margin_top === "auto") {
$style->set_used("margin_top", 0.0);
}
if ($style->margin_bottom === "auto") {
$style->set_used("margin_bottom", 0.0);
}
}
}