<?php
/**
 * Shared formatting for Client Monitor wording.
 *
 * @package TurtleReport
 */

namespace TurtleReport\Attention;

use TurtleReport\Profiles\Profile;
use TurtleReport\Support\Text;

defined( 'ABSPATH' ) || exit;

/**
 * Numbers, changes, page names and key-metric rows shared by every kind of
 * Client Monitor issue, so all of them read the same way.
 */
final class Wording {

	/**
	 * Adds the "early signal" note to insights when the numbers are small.
	 *
	 * @param string[] $insights Insights.
	 * @param array    $conf     Confidence.
	 * @return string[]
	 */
	public static function with_confidence( array $insights, array $conf ) {
		unset( $conf ); // Shown once, as the confidence note under the checks.
		return array_values( array_filter( $insights ) );
	}

	/**
	 * A metric tile.
	 *
	 * @param string     $label  Label.
	 * @param string     $value  Value now.
	 * @param float|null $change Percentage change.
	 * @return array
	 */
	public static function metric( $label, $value, $change ) {
		return array(
			'label'  => $label,
			'value'  => $value,
			'change' => null === $change ? '' : self::signed( (float) $change ),
			'tone'   => null === $change || abs( (float) $change ) < 1 ? 'flat' : ( $change < 0 ? 'bad' : 'good' ),
		);
	}

	/**
	 * A before/now row for the details table.
	 *
	 * @param string     $label  Label.
	 * @param float|null $before Before.
	 * @param float|null $now    Now.
	 * @param string     $kind   number|ratio|position.
	 * @return array
	 */
	public static function fact( $label, $before, $now, $kind = 'number' ) {
		$before = null === $before ? null : (float) $before;
		$now    = null === $now ? null : (float) $now;
		if ( 'position' === $kind ) {
			$delta = null !== $before && null !== $now ? $now - $before : null;
			return array(
				'label'  => $label,
				'before' => self::pos( $before ),
				'now'    => self::pos( $now ),
				'change' => null === $delta ? '' : ( abs( $delta ) < 0.05 ? '0.0' : ( $delta > 0 ? '▼ ' : '▲ ' ) . number_format_i18n( abs( $delta ), 1 ) ),
				'tone'   => null === $delta || abs( $delta ) < 0.5 ? 'flat' : ( $delta > 0 ? 'bad' : 'good' ),
			);
		}
		if ( 'ratio' === $kind ) {
			$pts = null !== $before && null !== $now ? ( $now - $before ) * 100 : null;
			return array(
				'label'  => $label,
				'before' => self::pct( $before ),
				'now'    => self::pct( $now ),
				'change' => null === $pts ? '' : self::pts( $pts ),
				'tone'   => null === $pts || abs( $pts ) < 0.1 ? 'flat' : ( $pts < 0 ? 'bad' : 'good' ),
			);
		}
		$change = null !== $before && null !== $now ? Rules::change( $now, $before ) : null;
		return array(
			'label'  => $label,
			'before' => self::num( $before ),
			'now'    => self::num( $now ),
			'change' => null === $change ? '' : self::signed( $change ),
			'tone'   => null === $change || abs( $change ) < 1 ? 'flat' : ( $change < 0 ? 'bad' : 'good' ),
		);
	}

	/**
	 * The website's address from its Search Console property, or ''.
	 *
	 * @param Profile $site Site.
	 * @return string
	 */
	public static function site_url( Profile $site ) {
		$prop = (string) $site->gsc_site;
		if ( 0 === strpos( $prop, 'sc-domain:' ) ) {
			return 'https://' . substr( $prop, 10 ) . '/';
		}
		return 0 === strpos( $prop, 'http' ) ? $prop : '';
	}

	/**
	 * A readable name for a page, from its address:
	 * /water-blasting-house-cleaning-cost/ → "Water blasting house cleaning cost page".
	 *
	 * @param string $url URL or path.
	 * @return string
	 */
	public static function page_name( $url ) {
		$path = self::path( (string) $url );
		$path = (string) strtok( $path, '?' );
		$bits = array_values(
			array_filter(
				explode( '/', $path ),
				static function ( $part ) {
					return '' !== $part;
				}
			)
		);
		if ( ! $bits ) {
			return __( 'The home page', 'turtlereport' );
		}
		$slug = rawurldecode( (string) end( $bits ) );
		$slug = preg_replace( '/\.(html?|php|aspx?)$/i', '', $slug );
		$name = trim( preg_replace( '/[-_]+/', ' ', $slug ) );
		if ( '' === $name ) {
			return $path;
		}
		/* translators: %s: page name made from its address, e.g. "Pricing". */
		return sprintf( __( 'The %s page', 'turtlereport' ), $name );
	}

	/**
	 * A page name for the middle of a sentence: "the pricing page".
	 *
	 * @param string $url URL or path.
	 * @return string
	 */
	public static function page_ref( $url ) {
		return Text::lower_first( self::page_name( $url ) );
	}

	/**
	 * A nested value with a default.
	 *
	 * @param array    $arr     Array.
	 * @param string[] $path    Keys.
	 * @param mixed    $fallback Default.
	 * @return mixed
	 */
	public static function val( $arr, array $path, $fallback = 0 ) {
		foreach ( $path as $key ) {
			if ( ! is_array( $arr ) || ! array_key_exists( $key, $arr ) ) {
				return $fallback;
			}
			$arr = $arr[ $key ];
		}
		return null === $arr ? $fallback : $arr;
	}

	/**
	 * A whole number for people.
	 *
	 * @param float|null $n Number.
	 * @return string
	 */
	public static function num( $n ) {
		return null === $n ? '–' : number_format_i18n( round( (float) $n ) );
	}

	/**
	 * A ratio as a percentage, e.g. 0.034 → "3.4%".
	 *
	 * @param float|null $ratio Ratio.
	 * @return string
	 */
	public static function pct( $ratio ) {
		return null === $ratio ? '–' : number_format_i18n( (float) $ratio * 100, 1 ) . '%';
	}

	/**
	 * Percentage points, e.g. -0.52 → "-0.5 pts".
	 *
	 * @param float $pts Points.
	 * @return string
	 */
	public static function pts( $pts ) {
		$pts = (float) $pts;
		/* translators: %s: change in percentage points, e.g. "+0.4". */
		return sprintf( __( '%s pts', 'turtlereport' ), ( $pts > 0.05 ? '+' : ( $pts < -0.05 ? '-' : '' ) ) . number_format_i18n( abs( $pts ), 1 ) );
	}

	/**
	 * A percentage change without its sign, e.g. -32.4 → "32%".
	 *
	 * @param float $change Change.
	 * @return string
	 */
	public static function pct_abs( $change ) {
		return number_format_i18n( abs( round( (float) $change ) ) ) . '%';
	}

	/**
	 * A signed percentage change, e.g. "+12%" or "-32%".
	 *
	 * @param float $change Change.
	 * @return string
	 */
	public static function signed( $change ) {
		$r = round( (float) $change );
		return ( $r > 0 ? '+' : ( $r < 0 ? '-' : '' ) ) . number_format_i18n( abs( $r ) ) . '%';
	}

	/**
	 * Change from before to now as text, or "–".
	 *
	 * @param float $now    Now.
	 * @param float $before Before.
	 * @return string
	 */
	public static function change_text( $now, $before ) {
		$change = Rules::change( (float) $now, (float) $before );
		return null === $change ? '–' : self::signed( $change );
	}

	/**
	 * A position, one decimal.
	 *
	 * @param float|null $pos Position.
	 * @return string
	 */
	public static function pos( $pos ) {
		return null === $pos || ! $pos ? '–' : number_format_i18n( (float) $pos, 1 );
	}

	/**
	 * A page URL shown as its path.
	 *
	 * @param string $url URL.
	 * @return string
	 */
	public static function path( $url ) {
		$parts = wp_parse_url( (string) $url );
		if ( ! is_array( $parts ) || empty( $parts['host'] ) ) {
			return (string) $url;
		}
		$path = isset( $parts['path'] ) && '' !== $parts['path'] ? $parts['path'] : '/';
		return $path . ( isset( $parts['query'] ) ? '?' . $parts['query'] : '' );
	}

	/**
	 * A date range, e.g. "14 Sep – 11 Oct".
	 *
	 * @param string $s Start (Y-m-d).
	 * @param string $e End (Y-m-d).
	 * @return string
	 */
	public static function range( $s, $e ) {
		if ( '' === $s || '' === $e ) {
			return '';
		}
		$fmt = static function ( $ymd ) {
			return wp_date( 'j M', strtotime( $ymd . ' 12:00:00 UTC' ), new \DateTimeZone( 'UTC' ) );
		};
		return $fmt( $s ) . ' – ' . $fmt( $e );
	}
}