<?php
/**
 * Main class for the Daemon setup
 *
 * @package LBRYPress
 */

class LBRY_Daemon
{
    /**
     * The address of the Lbry Daemon
     * @var string
     */
    private $address = 'localhost:5279';

    /**
     * The Daemon's Status
     */
    private $daemon_running = false;

    /**
    * The Daemon Notice Handler
    */
    private $notice = null;

    /**
     * The Daemon Logger
     * @var LBRY_Daemon_Logger
     */
    public $logger = null;

    /**
     * LBRY Daemon Object constructor
     */
    public function __construct()
    {
        $this->logger = new LBRY_Daemon_Logger();
        $this->notice = new LBRY_Admin_Notice();
        $this->daemon_running = $this->test_daemon();

        if (!$this->daemon_running) {
            $this->start_daemon();
            $this->notice->set_notice('error', 'Cannot connect to the LBRY Daemon. Attempting to start daemon server. <br /> If you are still having troubles, click <a href="' . admin_url('admin.php?page=lbrypress-help') . '">HERE</a> for help.');
        }
    }

    /**
     * Returns a boolean representation of daemon status
     * @return bool Whether or not the daemon is running
     */
    private function test_daemon()
    {
        try {
            $result = $this->request('status')->result;
            return $result->is_running;
        } catch (LBRYDaemonException $e) {
            $this->logger->log('daemon_status_error', $e->getMessage() . ' | Code: ' . $e->getCode());
            return false;
        }
    }

    /**
     * Attempts to start the daemon
     */
    private function start_daemon()
    {
        // Check if a daemon start process is already running
        $options = get_option(LBRY_SETTINGS);
        if ($options[LBRY_DAEMON_PID]) {
            if ($this->is_process_running($options[LBRY_DAEMON_PID])) {
                return;
            }

            $options[LBRY_DAEMON_PID] = false;
            update_option(LBRY_SETTINGS, $options);
        }

        // Using proc_open to set up the request
        // Again, this is unix only
        $cmd = ABSPATH . "lbrynet start";
        $command =  $cmd . ' > /dev/null 2> /dev/null & echo $!;';
        $pid = exec($command);

        if ($pid) {
            $options = get_option(LBRY_SETTINGS);
            $options[LBRY_DAEMON_PID] = $pid;
            update_option(LBRY_SETTINGS, $options);
        }
    }

    /**
     * Attempts to stop the daemon
     */
    private function stop_daemon()
    {
        exec(ABSPATH . 'lbrynet stop > /dev/null 2> /dev/null &');
    }

    /**
     * Checks to see if a PID is currently running
     * @param  int  $pid
     * @return boolean
     */
    private function is_process_running($pid)
    {
        // This is unix specific
        $lines_out = array();
        exec('ps '.(int)$pid, $lines_out);
        if(count($lines_out) >= 2) {
          // Process is running
          return true;
        }
        return false;
    }

    /**
     * Returns an unused address
     * https://lbry.tech/api/sdk#address_unused
     * @return string   Unused wallet address in base58
     */
    public function wallet_unused_address()
    {
        if (!$this->daemon_running) return;

        try {
            $result = $this->request('address_unused');
            return $result->result;
        } catch (LBRYDaemonException $e) {
            $this->logger->log('address_unused error', $e->getMessage() . ' | Code: ' . $e->getCode());
            $this->notice->set_notice('error', 'Issue getting unused address.');
            return;
        }
    }

    /**
     * Returns an paginated array of Address lists
     * https://lbry.tech/api/sdk#address_list
     * @param  int      $page   Pagination page number
     * @return array    Array of address lists linked to this account
     */
    public function address_list($page = 1)
    {
        if (!$this->daemon_running) return;

        // Get 20 per page
        $params = array(
            'page'  => $page,
            'page_size' => 20
        );
        try {
            $result = $this->request('address_list', $params);
            return $result->result->items;
        } catch (LBRYDaemonException $e) {
            $this->logger->log('address_list error', $e->getMessage() . ' | Code: ' . $e->getCode());
            $this->notice->set_notice('error', 'Issue getting address list.');
            return;
        }
    }

    /**
     * Returns the available balance of a current LBRY account
     * https://lbry.tech/api/sdk#account_balance
     * @param  string   $address    Wallet Address
     * @return float                Wallet Balance
     */
    public function wallet_balance()
    {
        if (!$this->daemon_running) return;

        try {
            $result = $this->request('account_balance');
            return $result->result->available;
        } catch (LBRYDaemonException $e) {
            $this->logger->log('account_balance error', $e->getMessage() . ' | Code: ' . $e->getCode());
            $this->notice->set_notice('error', 'Issue getting account balance.');
            return;
        }
    }

    /**
     * Returns a list of channels for this account
     * https://lbry.tech/api/sdk#channel_list
     * @param  int      $page    Pagination page number
     * @return array    claim dictionary or null if empty
     */
    public function channel_list($page = 1)
    {
        if (!$this->daemon_running) return;

        $params = array(
            'page'      => $page,
            'page_size' => 20
        );

        try {
            $result = $this->request('channel_list', $params)->result->items;
            return empty($result) ? null : $result;
        } catch (LBRYDaemonException $e) {
            $this->logger->log('channel_list error', $e->getMessage() . ' | Code: ' . $e->getCode());
            $this->notice->set_notice('error', 'Issue retrieving channel list.');
            return;
        }
    }

    /**
     * Create a claim for a new channel
     * https://lbry.tech/api/sdk#channel_create
     * @return array    dictionary containing result of the request
     */
    public function channel_new($channel_name, $bid_amount)
    {
        if (!$this->daemon_running) return;

        // TODO: Sanitize channel name and bid
        // Make sure no @ sign, as we will add that
        if (strpos($channel_name, '@')) {
            throw new \Exception('Illegal character "@" in channel name', 1);
        }

        // No white space allowed
        if (strpos($channel_name, ' ')) {
            throw new \Exception("No spaces allowed in channel name", 1);
        }

        $channel_name = '@' . $channel_name;

        try {
            $result = $this->request(
                'channel_create',
                array(
                    'name' => $channel_name,
                    'bid' => number_format(floatval($bid_amount), 2, '.', '')
                )
            );
            return $result->result;
        } catch (LBRYDaemonException $e) {
            $this->logger->log('channel_new error', $e->getMessage() . ' | Code: ' . $e->getCode());
            throw new \Exception('Issue creating new channel.', 1);
            return;
        }
    }

    /**
     * Returns the canonical URL for the supplied claim ID, null otherwise
     * @param  string $claim_id
     * @return string           Canonical URL, null if not found
     */
    public function canonical_url($claim_id = null)
    {
        if (!$this->daemon_running) return;

        if (!$claim_id) {
            return null;
        }

        try {
            $result = $this->request(
                'claim_search',
                array(
                    'claim_id'  => $claim_id,
                    'no_totals' => true
                )
            );

            $items = $result->result->items;
            if (!$items) {
                return null;
            }

            return $items[0]->canonical_url;
        } catch (LBRYDaemonException $e) {
            $this->logger->log('canonical_url error', $e->getMessage() . ' | Code: ' . $e->getCode());
            return;
        }
    }

    /**
     * Publishes a post to the LBRY Network
     * https://lbry.tech/api/sdk#publish
     * @param  array  $args        An array containing necessary data for publish post
     *
     *      Available params:
     *      ['name', 'bid', 'file_path', 'title', 'description', 'language', 'license', 'channel_id', 'thumbnail']
     *
     * @return object $result
     */
    public function publish($args)
    {
        if (!$this->daemon_running) return;

        try {
            $result = $this->request(
                'publish',
                $args
            );
            $this->logger->log('publish success!', 'Successfully published post with result: ' . print_r($result->result, true));
            return $result->result;
        } catch (LBRYDaemonException $e) {
            $this->logger->log('publish error', $e->getMessage() . ' | Code: ' . $e->getCode());
            $this->notice->set_notice('error', 'Issue publishing / updating post to LBRY Network.');
            return;
        }
    }

    /**
     * Sends a cURL request to the LBRY Daemon
     * @param  string   $method     The method to call on the LBRY API
     * @param  array    $params     The Parameters to send the LBRY API Call
     * @return string               The cURL response
     */
    private function request($method, $params = array())
    {
        // JSONify our request data
        $data = array(
            'method' => $method,
            'params' => $params
        );
        $data = json_encode($data);

        // Send it via curl
        $ch = curl_init();
        curl_setopt($ch, CURLOPT_URL, $this->address);
        curl_setopt($ch, CURLOPT_POST, true);
        curl_setopt($ch, CURLOPT_POSTFIELDS, $data);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
        curl_setopt($ch, CURLOPT_HTTPHEADER, array('Content-Type: application/json'));
        curl_setopt($ch, CURLOPT_AUTOREFERER, false);
        curl_setopt($ch, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_1_1);
        curl_setopt($ch, CURLOPT_HEADER, 0);

        $result = curl_exec($ch);
        $response_code = curl_getinfo($ch, CURLINFO_RESPONSE_CODE);
        curl_close($ch);

        if ($response_code != '200') {
            $this->logger->log("Damon Connection Issue", "Daemon connection returned response code $response_code");
            throw new LBRYDaemonException("Daemon Connection Issue", $response_code);
        }


        $result = json_decode($result);
        $this->check_for_errors($result);
        return $result;
    }

    /**
     * Checks for erros in decoded daemon response and throws an exception if it finds one
     * @param  $response
     */
    private function check_for_errors($response)
    {
        if (property_exists($response, 'error')) {
            $message = $response->error->message;
            $code = $response->error->code;
            $this->logger->log("Daemon error code $code", $message);
            throw new LBRYDaemonException($message, $code);
        }
    }

    /**
    * Temporary placeholder function for daemon. Not currently in use.
    * @return [type] [description]
    */
    // private function download_daemon()
    // {
    //     $output_filename = "lbrydaemon";
    //
    //     // HACK: Shouldn't just directly download, need to know OS, etc
    //     // TODO: Make sure we are only installing if not there or corrupted
    //     $host = "http://build.lbry.io/daemon/build-6788_commit-5099e19_branch-lbryum-refactor/mac/lbrynet";
    //     $fp = fopen(LBRY_URI . '/' . $output_filename, 'w+');
    //     $ch = curl_init();
    //     curl_setopt($ch, CURLOPT_URL, $host);
    //     curl_setopt($ch, CURLOPT_VERBOSE, 1);
    //     curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
    //     curl_setopt($ch, CURLOPT_FILE, $fp);
    //     curl_setopt($ch, CURLOPT_AUTOREFERER, false);
    //     curl_setopt($ch, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_1_1);
    //     curl_setopt($ch, CURLOPT_HEADER, 0);
    //
    //     $result = curl_exec($ch);
    //     curl_close($ch);
    //     fclose($fp);
    //
    //     $filepath = LBRY_URI . '/' . $output_filename;
    //
    //     `chmod +x  {$filepath}`;
    //     error_log(`{$filepath} status`);
    //     `{$filepath} start &`;
    // }
}

class LBRYDaemonException extends Exception
{
    public function __contstruct($message = '', $code = 0, Exception $previous = null)
    {
        parent::__construct($message, $code, $previous);
    }
}