<?php

namespace Adventurebook;

use ReflectionException;
use ReflectionFunction;

class Script {

	public int $id;
	public string $code;
	public string $name;
	public array $commands;

	public bool $show_decisions = true;

	private int $_current_key = 0;
	public function __construct( $id, $code, $name, $commands ) {
		$this->id       = $id;
		$this->code     = $code;
		$this->name     = $name;
		$this->commands = json_decode( $commands, true );
	}

	public static function get_script_by_id( int $id ): ?Script {
		if ( $id <= 0 ) {
			return null;
		}
		global $wpdb;
		$result = $wpdb->get_row( $wpdb->prepare( "SELECT * FROM " . $wpdb->prefix . "adventurebook_scripts WHERE id = %d", $id ), ARRAY_A ); // phpcs:ignore WordPress.DB.DirectDatabaseQuery

		if ( $result === null ) {
			return null;
		}

		return new Script( $result['id'], $result['code'], $result['name'], $result['commands'] );
	}

	public static function get_script_by_code( string $code ): ?Script {
		global $wpdb;
		$result = $wpdb->get_row( $wpdb->prepare( "SELECT * FROM " . $wpdb->prefix . "adventurebook_scripts WHERE code = %s", $code ), ARRAY_A ); // phpcs:ignore WordPress.DB.DirectDatabaseQuery
		if ( $result === null ) {
			return null;
		}

		return new Script( $result['id'], $result['code'], $result['name'], $result['commands'] );
	}

	public static function get_all_scripts(): array {
		global $wpdb;
		$results = $wpdb->get_results( "SELECT * FROM " . $wpdb->prefix . "adventurebook_scripts", ARRAY_A ); // phpcs:ignore WordPress.DB.DirectDatabaseQuery
		$scripts = array();
		foreach ( $results as $result ) {
			$scripts[] = new Script( $result['id'], $result['code'], $result['name'], $result['commands'] );
		}

		//  sort by name
		usort( $scripts, function ( $a, $b ) {
			return strcmp( $a->name, $b->name );
		} );

		return $scripts;
	}

	public static function create_script( string $code, string $name, array $commands ): void {
		global $wpdb;
		$table_name = $wpdb->prefix . 'adventurebook_scripts';
		$wpdb->insert( $table_name, array( // phpcs:ignore WordPress.DB.DirectDatabaseQuery
			'code'     => $code,
			'name'     => $name,
			'commands' => json_encode( $commands ),
		) );
	}

	public static function create_script_from_textfield(string $code, string $name, string $commands_textfield): void {
		$commands_info = [];
		// Sanitize textarea input and split into lines
		$lines = explode("\n", $commands_textfield);
		foreach ($lines as $line) {
			// Each line should be in the format: key|command|parameters
			// Example: 10|output|Hello World!|red
			//          20|heal|10
			// Trim whitespace and skip empty lines
			if (trim($line) === '') {
				continue;
			}
			// Split line into parts
			list( $key, $command, $parameters ) =  explode( '|', trim( $line ), 3 );
			$key = intval($key);
			$command?:$command = strtolower(trim($command));
			$parameters = trim($parameters);
			if($key <= 0 || !$command) {
				// skip invalid lines
				continue;
			}
			// Add to commands array
			$commands_info[] = [
				'key' => $key,
				'command' => $command,
				'parameters' => $parameters,
			];
		}
		self::create_script($code, $name, $commands_info);
	}

	public static function update_script( int $id, string $code, string $name, array $commands ): void {
		global $wpdb;
		$table_name = $wpdb->prefix . 'adventurebook_scripts';
		$wpdb->update( $table_name, array( // phpcs:ignore WordPress.DB.DirectDatabaseQuery
			'code'     => $code,
			'name'     => $name,
			'commands' => json_encode( $commands ),
		), array( 'id' => $id ) );
	}

	public static function delete_script( int $id ): void {
		global $wpdb;
		$table_name = $wpdb->prefix . 'adventurebook_scripts';
		$wpdb->delete( $table_name, array( 'id' => $id ) ); // phpcs:ignore WordPress.DB.DirectDatabaseQuery
	}

	/**
	 * Move the internal pointer to the next command.
	 *
	 * @return true a next command is available, false when the script has ended.
	 */
	public function next() : bool {
		if ( $this->_current_key == - 1 ) {
			//  script has ended
			return false;
		}
		if($this->_current_key == 0) {
			//  start at the beginning
			$this->_current_key = $this->get_first_key();
			if($this->_current_key == 0) {
				//  no commands in this script
				return false;
			}
			return true;
		}
		$this->_current_key = $this->get_next_key( $this->_current_key );
		return true;
	}

	public function run_script(Character $character, ?string $script_data = ''): array {
		// aktuelle Position aus den Game-Variablen
		$this->_current_key = intval($character->get_game_var("script_" . $this->code . "_key"));
		if ($this->_current_key <= 0) {
			// start at the beginning
			$this->_current_key = $this->get_first_key();
		}

		$output = [];

		while ($this->_current_key != -1) {
			//  find the command with the current key
			$command_info = $this->get_command_by_key($this->_current_key);

			if ($command_info === null) {
				// command not found → stop the script
				$this->_current_key = -1;
				break;
			}

			// execute the command via dynamic Command-Array
			//  merge the output from execute command into the output array
			$command_output = $this->execute_command($command_info, $character, $script_data);
			$output = array_merge($output, $command_output);

			// speichere aktuelle Position, damit das Script beim nächsten Mal weiterläuft
			$character->set_game_var("script_" . $this->code . "_key", $this->_current_key);

			// move to next key, falls der Befehl nicht bereits gesprungen ist
			if ($this->_current_key != -1 && $this->_current_key == $command_info['key']) {
				$this->_current_key = $this->get_next_key($this->_current_key);
			}
		}

		return $output;
	}


	public function get_next_key( int $current_key ): int {
		$found_current = false;
		foreach ( $this->commands as $command ) {
			if ( $found_current ) {
				return intval( $command['key'] );
			}
			if ( $command['key'] == $current_key ) {
				$found_current = true;
			}
		}

		return 0;
	}

	public function get_command_by_key( int $key ): ?array {
		foreach ( $this->commands as $command ) {
			if ( $command['key'] == $key ) {
				return $command;
			}
		}

		return null;
	}

	public function get_first_key(): int {
		if ( count( $this->commands ) > 0 ) {
			return intval( $this->commands[0]['key'] );
		}

		return 0;
	}

	/**
	 * Returns an array of all available commands, including premium commands if applicable.
	 *
	 * @param Character|null $character Optional character context for command functions.
	 * @return array Associative array of command names to their corresponding callable functions.
	 */
	public function get_all_commands(?Character $character = null): array {
		$commands = $this->get_core_commands($character);

		// premium commands if defined
		if (defined('ADVENTUREBOOK_PREMIUM') && ADVENTUREBOOK_PREMIUM) {
			$pro_commands = include ADVENTUREBOOK_PATH . 'includes/premium/script_commands_premium.php';
			$commands = array_merge($commands, $pro_commands);
		}

		//  sort commands by key
		ksort($commands);
		return $commands;
	}

	public function get_core_commands(?Character $character = null): array {
		return [
			/* adds an effect to the character
			   Usage: add_effect effect_name|effect_type|duration|power (see AbstractCombatant::add_effect for details)
			*/
			'add_effect' => function($parameters) use ($character) {
				$parts = explode('|', $parameters, 4);
				if(count($parts) == 4) {
					$effect_name = trim($parts[0]);
					$effect_type = trim($parts[1]);
					$duration    = intval(trim($parts[2]));
					$power       = intval(trim($parts[3]));
					$character->add_effect($effect_name, $effect_type, $duration, $power);
				}
				return [];
			},
			/* Adds an item to the character's inventory
			   Usage: add_item item_code
			*/
			'add_item' => function($parameters) use ($character) {
				$item_definition = Item_Definition::get_item_definition_by_code($parameters);
				if($item_definition !== null) {
					$character->add_item_to_inventory($parameters);
					/* translators: %s is the item name */
					return ['<font color="blue">' . sprintf(__('You received item: %s', 'adventurebook'), $item_definition->name) . '</font>'];
				}
				return [];
			},

			/* Heals the character by the specified amount, or full if amount is -1
			   Usage: heal amount
			*/
			'heal' => function($parameters) use ($character) {
				$character->heal(intval($parameters));
				return [];
			},
			/* Jumps to a specific script key if the character has the given effect
			   Usage: if_effect_goto effect_name|key
			*/
			'if_effect_goto' => function($parameters) use ($character) {
				$parts = explode('|', $parameters, 2);
				if(count($parts) == 2) {
					$effect_name = trim($parts[0]);
					$goto_key  = intval(trim($parts[1]));
					if($character->has_effect($effect_name)) {
						$this->_current_key = $goto_key;
					}
				}
				return [];
			},
			/* Jumps to a specific script key if the given item is at the current location
			   Usage: if_item_is_here_goto item_code|key
			*/
			'if_item_is_here_goto' => function($parameters) use ($character) {
				$parts = explode('|', $parameters, 2);
				if(count($parts) == 2) {
					$item_code = trim($parts[0]);
					$goto_key  = intval(trim($parts[1]));
					$items_here = get_items_for_page($character->location_id, $character->id);
					foreach($items_here as $item) {
						if($item->code === $item_code) {
							$this->_current_key = $goto_key;
							break;
						}
					}
				}
				return [];
			},
			/* Outputs text to the user, optionally in a specific color
			   Usage: output text|color
			   Example: output Hello World!|red
			            output Hello World!
			*/
			'output' => function($parameters) use ($character) {
				$parts = explode('|', $parameters, 2);
				$text  = trim($parts[0]);
				$text  = $this->prepare_text($text, $character);
				$color = count($parts) == 2 ? trim($parts[1]) : '';

				if ($color !== '') {
					return ['<font color="' . esc_attr($color) . '">' . esc_html($text) . '</font>'];
				}
				return [esc_html($text)];
			},
			/* Removes an effect from the character
			   Usage: remove_effect effect_name
			 */
			'remove_effect' => function($parameters) use ($character) {
				$effect_name = trim($parameters);
				$character->remove_effect($effect_name);
				return [];
			},
			/* Removes an item from the character's inventory and deletes it
			   Usage: remove_item item_code
			*/
			'remove_item' => function($parameters) use ($character) {
				$item_definition = Item_Definition::get_item_definition_by_code($parameters);
				if($item_definition !== null) {
					if($character->delete_itemcode_from_inventory($parameters)) {
						/* translators: %s is the item name */
						return ['<font color="blue">' . sprintf(__('You lost item: %s', 'adventurebook'), $item_definition->name) . '</font>'];
					} else {
						/* translators: %s is the item name */
						return ['<font color="red">' . sprintf(__('Item not found in inventory: %s', 'adventurebook'), $item_definition->name) . '</font>'];
					}
				}
				return [];
			},
			/* Shows a button that jumps to a specific script key when clicked
			   Usage: show_key_link link_text|key
			   Example: show_key_link Go to next part|10
			*/
			'show_key_link' => function($parameters) use ($character) {
				$parts = explode('|', $parameters, 2);
				if(count($parts) == 2) {
					$link_text = trim($parts[0]);
					$goto_key = intval(trim($parts[1]));
					return ['<button class="adventurebook_script_action_button" onclick="adventurebook_setKeyForScriptAndRefresh(\''
					       . esc_js($this->code) . '\','
					       . esc_js($goto_key) . ','
					       . esc_js($character->id) . ','
					       . esc_js($character->adventurebook_id) . ');return false;">'
					       . esc_html($link_text) . '</button><br>'];
				}
				return [];
			},
			/* Stops the script immediately
			   Usage: stop
			*/
			'stop' => function($parameters) {
				$this->_current_key = -1;
				return [];
			},
		];
	}

	/**
	 * @throws ReflectionException
	 */
	public function execute_command(array $command_info, Character $character, ?string $script_data = ''): array {
		$output     = [];
		$key        = $command_info['key'];
		$command    = strtolower($command_info['command']);
		$parameters = $command_info['parameters'];

		$commands = $this->get_core_commands($character);

		// Pro-Commands laden, nur wenn definiert
		if (defined('ADVENTUREBOOK_PREMIUM') && ADVENTUREBOOK_PREMIUM) {
			$pro_commands = include ADVENTUREBOOK_PATH . 'includes/premium/script_commands_premium.php';
			$commands = array_merge($commands, $pro_commands);
		}

		if (isset($commands[$command])) {
			// $character and $this (Script) are available in the command functions via "use"
			//  check if the command has two or three parameters (some commands need the script_data)
			$refFunc = new ReflectionFunction( $commands[ $command ] );
			if ( $refFunc->getNumberOfParameters() == 3 ) {
				$output = array_merge($output, $commands[ $command ]( $parameters, $character, $script_data )
				);
			} else {
				$output = array_merge($output, $commands[ $command ]( $parameters, $character, $this ));
			}
		} else {
			$output[] = '<span style="color:red;">Unknown command: ' . esc_html($command) . '</span>';
		}

		// move to next command if not changed
		if($this->_current_key != -1 && $this->_current_key == $key) {
			$this->_current_key = $this->get_next_key($this->_current_key);
		}

		return $output;
	}


	/**
	 * Prepare text for output by replacing placeholders with actual values.
	 *
	 * Supported placeholders:
	 * - {var:varname}: Replaced with the value of the game variable "varname".
	 * - {stat:statname}: Replaced with the value of the character's stat "statname".
	 * - {itemcount:itemcode}: Replaced with the count of the item "itemcode" in the character's inventory.
	 * - {charactername}: Replaced with the name of the character.
	 *
	 * @param string $text The text to prepare.
	 * @param Character $character The character for whom to prepare the text.
	 *
	 * @return string The prepared text, safe for HTML output.
	 */
	private function prepare_text( string $text, Character $character ): string {
		//  prepare text for output, e.g. by escaping HTML special characters

		//  if $text contains {var:varname}, replace it with the value of the game var "varname"
		preg_match_all( '/\{var:([a-zA-Z0-9_]+)\}/', $text, $matches );
		if ( count( $matches ) == 2 ) {
			foreach ( $matches[1] as $var_name ) {
				$var_value = $character->get_game_var( $var_name );
				$text      = str_replace( '{var:' . $var_name . '}', $var_value, $text );
			}
		}

		//  if $text contains {stat:statname}, replace it with the value of the stat "statname"
		preg_match_all( '/\{stat:([a-zA-Z0-9_]+)\}/', $text, $matches );
		if ( count( $matches ) == 2 ) {
			foreach ( $matches[1] as $stat_name ) {
				$stat_value = $character->get_stat( $stat_name );
				$text       = str_replace( '{stat:' . $stat_name . '}', $stat_value, $text );
			}
		}

		//  if $text contains {itemcount:itemcode}, replace it with the count of the item "itemcode" in the inventory
		preg_match_all( '/\{itemcount:([a-zA-Z0-9_]+)\}/', $text, $matches );
		if ( count( $matches ) == 2 ) {
			foreach ( $matches[1] as $item_code ) {
				$item_count = $character->get_item_count_by_code( $item_code, false );
				$text       = str_replace( '{itemcount:' . $item_code . '}', $item_count, $text );
			}
		}

		//  if $text contains {charactername}, replace it with the name of the character
		$text = str_replace( '{charactername}', $character->get_name(), $text );

		return esc_html( $text );
	}

	/**
	 * Get all scripts that are used by pages in the given adventurebook.
	 *
	 * @param int $adventurebook_id The ID of the adventurebook.
	 * @return array An array of Script objects.
	 */
	public static function get_all_scripts_by_adventurebook_id(int $adventurebook_id): array {
		global $wpdb;
		//  we need to look in every adventurebook_page for the _adventurebook_page_script option and then get the script
		$results = $wpdb->get_results($wpdb->prepare( //  phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching
			"SELECT DISTINCT s.* 
			FROM " . $wpdb->prefix . "adventurebook_scripts s
			JOIN " . $wpdb->prefix . "posts p ON p.post_parent = %d
			JOIN " . $wpdb->prefix . "postmeta pm ON pm.post_id = p.ID AND pm.meta_key = '_adventurebook_page_script' AND pm.meta_value = s.code",
			$adventurebook_id
		), ARRAY_A);// phpcs:ignore WordPress.DB.DirectDatabaseQuery
		$scripts = array();
		foreach ($results as $result) {
			$scripts[] = new Script($result['id'], $result['code'], $result['name'], $result['commands']);
		}
		//  we also need to look in every item that has a "Use" stat. The Value of the "Use" stat is a script_code.
		//  get all item definitions that have a "Use" stat
		$item_definitions = Item_Definition::get_all_item_definitions();
		foreach ($item_definitions as $item_definition) {
			/* @var Item_Definition $item_definition */
			$use_script_code = $item_definition->get_stat('Use');
			if ($use_script_code !== null && $use_script_code !== '') {
				$script = Script::get_script_by_code($use_script_code);
				//  check if a script with the same code is already in the array
				//  we can't just use array_unique because we have distinct objects (instances of Script)
				$found = false;
				foreach ($scripts as $s) {
					if ( $s->code === $use_script_code ) {
						$found = true;
						break;
					}
				}
				if (!$found && $script !== null) {
					$scripts[] = $script;
				}
			}
		}

		//  sort by name
		usort($scripts, function ($a, $b) {
			return strcmp($a->name, $b->name);
		});

		return $scripts;
	}

	/**
	 * Get all item definitions that are referenced in this script via add_item or remove_item commands.
	 *
	 * @return Item_Definition[] Array of Item_Definition objects.
	 */
	public function get_all_item_definitions(): array {
		//  iterate through all commands and find the item code parameters when the command is add_item or remove_item
		$item_codes = [];
		foreach ($this->commands as $command) {
			$cmd = strtolower( $command['command'] );
			if ( $cmd === 'add_item' || $cmd === 'remove_item' ) {
				$item_code = trim( $command['parameters'] );
				if ( $item_code !== '' && ! in_array( $item_code, $item_codes ) ) {
					$item_codes[] = $item_code;
				}
			}
		}
		//  get the item definitions for the found item codes
		$item_definitions = [];
		foreach ( $item_codes as $item_code ) {
			$item_definition = Item_Definition::get_item_definition_by_code( $item_code );
			if ( $item_definition !== null ) {
				$item_definitions[] = $item_definition;
			}
		}
		return $item_definitions;
	}

}