extract.php

<?php
require_once dirname( __FILE__ ) . '/pomo/entry.php';
require_once dirname( __FILE__ ) . '/pomo/translations.php';

class StringExtractor
{
    public $rules = array();
    public $comment_prefix = 'translators:';

    public function __construct( $rules = array() )
    {
        $this->rules = $rules;
    }

    public function extract_from_directory( $dir, $excludes = array(), $includes = array(), $prefix = '' )
    {
        $old_cwd = getcwd();
        chdir( $dir );
        $translations = new Translations;
        $file_names = (array) scandir( '.' );
        foreach ($file_names as $file_name) {
            if ( '.' == $file_name || '..' == $file_name ) continue;
            $extracted = false;
            if ( preg_match( '/\.php$/', $file_name ) && $this->does_file_name_match( $prefix . $file_name, $excludes, $includes ) ) {
                $extracted = $this->extract_from_file( $file_name, $prefix);
            }
            if ( is_dir( $file_name ) ) {
                $extracted = $this->extract_from_directory( $file_name, $excludes, $includes, $prefix . $file_name . '/' );
            }
            if ($extracted) {
                $translations->merge_originals_with($extracted);
            }
        }
        chdir( $old_cwd );

        return $translations;
    }

    public function extract_from_file( $file_name, $prefix )
    {
        $code = file_get_contents( $file_name );

        return $this->extract_entries( $code, $prefix . $file_name );
    }

    public function does_file_name_match( $path, $excludes, $includes )
    {
        if ($includes) {
            $matched_any_include = false;
            foreach ($includes as $include) {
                if ( preg_match( '|^'.$include.'$|', $path ) ) {
                    $matched_any_include = true;
                    break;
                }
            }
            if ( !$matched_any_include ) return false;
        }
        if ($excludes) {
            foreach ($excludes as $exclude) {
                if ( preg_match( '|^'.$exclude.'$|', $path ) ) {
                    return false;
                }
            }
        }

        return true;
    }

    public function entry_from_call( $call, $file_name )
    {
        $rule = isset( $this->rules[$call['name']] )? $this->rules[$call['name']] : null;
        if ( !$rule ) return null;
        $entry = new Translation_Entry;
        $multiple = array();
        $complete = false;
        for ( $i = 0; $i < count( $rule ); ++$i ) {
            if ( $rule[$i] && ( !isset( $call['args'][$i] ) || !is_string( $call['args'][$i] ) || '' == $call['args'][$i] ) ) return false;
            switch ($rule[$i]) {
            case 'string':
                if ($complete) {
                    $multiple[] = $entry;
                    $entry = new Translation_Entry;
                    $complete = false;
                }
                $entry->singular = $call['args'][$i];
                $complete = true;
                break;
            case 'singular':
                if ($complete) {
                    $multiple[] = $entry;
                    $entry = new Translation_Entry;
                    $complete = false;
                }
                $entry->singular = $call['args'][$i];
                $entry->is_plural = true;
                break;
            case 'plural':
                $entry->plural = $call['args'][$i];
                $entry->is_plural = true;
                $complete = true;
                break;
            case 'context':
                $entry->context = $call['args'][$i];
                foreach ($multiple as &$single_entry) {
                    $single_entry->context = $entry->context;
                }
                break;
            }
        }
        if ( isset( $call['line'] ) && $call['line'] ) {
            $references = array( $file_name . ':' . $call['line'] );
            $entry->references = $references;
            foreach ($multiple as &$single_entry) {
                $single_entry->references = $references;
            }
        }
        if ( isset( $call['comment'] ) && $call['comment'] ) {
            $comments = rtrim( $call['comment'] ) . "\n";
            $entry->extracted_comments = $comments;
            foreach ($multiple as &$single_entry) {
                $single_entry->extracted_comments = $comments;
            }
        }
        if ($multiple && $entry) {
            $multiple[] = $entry;

            return $multiple;
        }

        return $entry;
    }

    public function extract_entries( $code, $file_name )
    {
        $translations = new Translations;
        $function_calls = $this->find_function_calls( array_keys( $this->rules ), $code );
        foreach ($function_calls as $call) {
            $entry = $this->entry_from_call( $call, $file_name );
            if ( is_array( $entry ) )
                foreach( $entry as $single_entry )
                    $translations->add_entry_or_merge( $single_entry );
            elseif ( $entry)
                $translations->add_entry_or_merge( $entry );
        }

        return $translations;
    }

    /**
     * Finds all function calls in $code and returns an array with an associative array for each function:
     *	- name - name of the function
     *	- args - array for the function arguments. Each string literal is represented by itself, other arguments are represented by null.
     *  - line - line number
     */
    public function find_function_calls( $function_names, $code )
    {
        $tokens = token_get_all( $code );
        $function_calls = array();
        $latest_comment = false;
        $in_func = false;
        foreach ($tokens as $token) {
            $id = $text = null;
            if ( is_array( $token ) ) list( $id, $text, $line ) = $token;
            if ( T_WHITESPACE == $id ) continue;
            if ( T_STRING == $id && in_array( $text, $function_names ) && !$in_func ) {
                $in_func = true;
                $paren_level = -1;
                $args = array();
                $func_name = $text;
                $func_line = $line;
                $func_comment = $latest_comment? $latest_comment : '';

                $just_got_into_func = true;
                $latest_comment = false;
                continue;
            }
            if (T_COMMENT == $id) {
                $text = trim( preg_replace( '%^/\*|//%', '', preg_replace( '%\*/$%', '', $text ) ) );
                if ( 0 === stripos( $text, $this->comment_prefix ) ) {
                    $latest_comment = $text;
                }
            }
            if ( !$in_func ) continue;
            if ( '(' == $token ) {
                $paren_level++;
                if (0 == $paren_level) { // start of first argument
                    $just_got_into_func = false;
                    $current_argument = null;
                    $current_argument_is_just_literal = true;
                }
                continue;
            }
            if ($just_got_into_func) {
                // there wasn't a opening paren just after the function name -- this means it is not a function
                $in_func = false;
                $just_got_into_func = false;
            }
            if ( ')' == $token ) {
                if (0 == $paren_level) {
                    $in_func = false;
                    $args[] = $current_argument;
                    $call = array( 'name' => $func_name, 'args' => $args, 'line' => $func_line );
                    if ( $func_comment ) $call['comment'] = $func_comment;
                    $function_calls[] = $call;
                }
                $paren_level--;
                continue;
            }
            if (',' == $token && 0 == $paren_level) {
                $args[] = $current_argument;
                $current_argument = null;
                $current_argument_is_just_literal = true;
                continue;
            }
            if (T_CONSTANT_ENCAPSED_STRING == $id && $current_argument_is_just_literal) {
                // we can use eval safely, because we are sure $text is just a string literal
                eval('$current_argument = '.$text.';' );
                continue;
            }
            $current_argument_is_just_literal = false;
            $current_argument = null;
        }

        return $function_calls;
    }
}