<?php

require_once("../inc/db_conn.inc");
require_once("../inc/util.inc");

class BossaDb extends DbConn {
    public static $instance;

    static function get() {
        if (!isset($instance)) {
            $config = get_config();
            $user = parse_config($config, '<bossa_db_user>');
            $passwd = parse_config($config, '<bossa_db_passwd>');
            $host = parse_config($config, '<bossa_db_host>');
            $name = parse_config($config, '<bossa_db_name>');
            if ($host == null) {
                $host = "localhost";
            }
            $instance = new DbConn();
            $retval = $instance->init_conn($user, $passwd, $host, $name);
            if (!$retval) return null;
        }
        return $instance;
    }
    static function escape_string($string) {
        $db = self::get();
        return $db->base_escape_string($string);
    }
}

class BossaApp {
    function insert($clause) {
        $db = BossaDb::get();
        return $db->insert('bossa_app', $clause);
    }

    static function lookup_name($name) {
        $db = BossaDb::get();
        return $db->lookup('bossa_app', 'BossaApp', "name='$name'");
    }

    static function lookup_id($id) {
        $db = BossaDb::get();
        return $db->lookup_id($id, 'bossa_app', 'BossaApp');
    }

    static function enum() {
        $db = BossaDb::get();
        return $db->enum('bossa_app', 'BossaApp');
    }
}

class BossaJob {
    function insert() {
        $db = BossaDb::get();
        $now = time();
        $query = "insert into DBNAME.bossa_job (create_time, name, app_id, info, batch, time_estimate, time_limit, nneeded) values ($now, '$this->name', $this->app_id, '$this->info', $this->batch, $this->time_estimate, $this->time_limit, $this->nneeded)";
        $result = $db->do_query($query);
        if (!$result) {
            echo "$query\n";
            return false;
        }
        $this->id = $db->insert_id();
        return true;
    }
    function update($clause) {
        $db = BossaDb::get();
        return $db->update($this, 'bossa_job', $clause);
    }
    static function lookup_id($id) {
        $db = BossaDb::get();
        return $db->lookup_id($id, 'bossa_job', 'BossaJob');
    }
    static function enum($clause) {
        $db = BossaDb::get();
        return $db->enum('bossa_job', 'BossaJob', $clause);
    }
}

class BossaJobInst {
    function insert() {
        $db = BossaDb::get();
        $now = time();
        $query = "insert into DBNAME.bossa_job_inst (create_time, job_id, user_id) values ($now, $this->job_id, $this->user_id)";
        $result = $db->do_query($query);
        if (!$result) {
            echo "$query\n";
            return false;
        }
        $this->id = $db->insert_id();
        return true;
    }

    static function lookup_id($id) {
        $db = BossaDb::get();
        return $db->lookup_id($id, 'bossa_job_inst', 'BossaJobInst');
    }
    static function enum($clause) {
        $db = BossaDb::get();
        return $db->enum('bossa_job_inst', 'BossaJobInst', $clause);
    }

    function update($clause) {
        $db = BossaDb::get();
        return $db->update($this, 'bossa_job_inst', $clause);
    }

    // Assign a job from the given app to the given user.
    // Returns the job instance or NULL.
    //
    static function assign($app, $user) {
        // this query skips jobs for which this user
        // has already been assigned an instance
        //
        // TODO: put the following in a transaction
        $db = BossaDb::get();
        $query = "select bossa_job.* from DBNAME.bossa_job left join DBNAME.bossa_job_inst on bossa_job_inst.job_id = bossa_job.id where bossa_job.nneeded>0 and bossa_job_inst.user_id is null limit 1";
        $result = $db->do_query($query);
        if (!$result) return null;
        $job = mysql_fetch_object($result, 'BossaJob');
        if (!$job) return null;
        mysql_free_result($result);

        $ji = new BossaJobInst();
        $ji->user_id = $user->id;
        $ji->job_id = $job->id;

        if (!$ji->insert()) {
            echo mysql_error();
            return null;
        }

        $job->update("nneeded=nneeded-1");
        return $ji;
    }

    // The given job instance has completed
    //
    function completed($job) {
        $this->finish_time = time();
        $this->update("finish_time=$this->finish_time, info='$this->info'");

        $now = time();
        return $job->update("transition_time=$now");
    }

    // The given job instance has timed out.
    //
    function timed_out($job) {
        $job->npending--;
        $job->more_needed = ($job->npending+$job->nsuccess < $job->nsuccess_needed);
        return $job->update("npending=$job->npending, more_needed=$job->more_needed");
    }
}

?>