// This file is part of BOINC.
// http://boinc.berkeley.edu
// Copyright (C) 2008 University of California
//
// BOINC is free software; you can redistribute it and/or modify it
// under the terms of the GNU Lesser General Public License
// as published by the Free Software Foundation,
// either version 3 of the License, or (at your option) any later version.
//
// BOINC is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
// See the GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with BOINC.  If not, see <http://www.gnu.org/licenses/>.

// sample_work_generator.C: an example BOINC work generator.
// This work generator has the following properties
// (you may need to change some or all of these):
//
// - Runs as a daemon, and creates an unbounded supply of work.
//   It attempts to maintain a "cushion" of 100 unsent job instances.
//   (your app may not work this way; e.g. you might create work in batches)
// - Creates work for the application "uppercase".
// - Creates a new input file for each job;
//   the file (and the workunit names) contain a timestamp
//   and sequence number, so that they're unique.

#include <unistd.h>
#include <cstdlib>
#include <string>
#include <cstring>

#include "boinc_db.h"
#include "error_numbers.h"
#include "backend_lib.h"
#include "parse.h"
#include "util.h"

#include "sched_config.h"
#include "sched_util.h"
#include "sched_msgs.h"
#include "str_util.h"

#define CUSHION 100
    // maintain at least this many unsent results
#define REPLICATION_FACTOR  2

// globals
//
char* wu_template;
DB_APP app;
int start_time;
int seqno;

// create one new job
//
int make_job() {
    DB_WORKUNIT wu;
    char name[256], path[256];
    const char* infiles[1];
    int retval;

    // make a unique name (for the job and its input file)
    //
    sprintf(name, "uc_%d_%d", start_time, seqno++);

    // Create the input file.
    // Put it at the right place in the download dir hierarchy
    //
    retval = config.download_path(name, path);
    if (retval) return retval;
    FILE* f = fopen(path, "w");
    if (!f) return ERR_FOPEN;
    fprintf(f, "This is the input file for job %s", name);
    fclose(f);

    // Fill in the job parameters
    //
    wu.clear();
    wu.appid = app.id;
    strcpy(wu.name, name);
    wu.rsc_fpops_est = 1e12;
    wu.rsc_fpops_bound = 1e14;
    wu.rsc_memory_bound = 1e8;
    wu.rsc_disk_bound = 1e8;
    wu.delay_bound = 86400;
    wu.min_quorum = REPLICATION_FACTOR;
    wu.target_nresults = REPLICATION_FACTOR;
    wu.max_error_results = REPLICATION_FACTOR*4;
    wu.max_total_results = REPLICATION_FACTOR*8;
    wu.max_success_results = REPLICATION_FACTOR*4;
    infiles[0] = name;

    // Register the job with BOINC
    //
    return create_work(
        wu,
        wu_template,
        "templates/uc_result",
        config.project_path("templates/uc_result"),
        infiles,
        1,
        config
    );
}

void main_loop() {
    int retval;

    while (1) {
        check_stop_daemons();
        int n;
        retval = count_unsent_results(n, 0);
        if (n > CUSHION) {
            sleep(60);
        } else {
            int njobs = (CUSHION-n)/REPLICATION_FACTOR;
            log_messages.printf(MSG_DEBUG,
                "Making %d jobs\n", njobs
            );
            for (int i=0; i<njobs; i++) {
                retval = make_job();
                if (retval) {
                    log_messages.printf(MSG_CRITICAL,
                        "can't make job: %d\n", retval
                    );
                    exit(retval);
                }
            }
            // Now sleep for a few seconds to let the transitioner
            // create instances for the jobs we just created.
            // Otherwise we could end up creating an excess of jobs.
            sleep(5);
        }
    }
}

int main(int argc, char** argv) {
    int i, retval;

    for (i=1; i<argc; i++) {
        if (!strcmp(argv[i], "-d")) {
            log_messages.set_debug_level(atoi(argv[++i]));
        } else {
            log_messages.printf(MSG_CRITICAL,
                "bad cmdline arg: %s", argv[i]
            );
        }
    }

    retval = config.parse_file();
    if (retval) {
        log_messages.printf(MSG_CRITICAL,
            "Can't parse config.xml: %s\n", boincerror(retval)
        );
        exit(1);
    }

    retval = boinc_db.open(
        config.db_name, config.db_host, config.db_user, config.db_passwd
    );
    if (retval) {
        log_messages.printf(MSG_CRITICAL, "can't open db\n");
        exit(1);
    }
    if (app.lookup("where name='uppercase'")) {
        log_messages.printf(MSG_CRITICAL, "can't find app\n");
        exit(1);
    }
    if (read_file_malloc(config.project_path("templates/uc_wu"), wu_template)) {
        log_messages.printf(MSG_CRITICAL, "can't read WU template\n");
        exit(1);
    }

    start_time = time(0);
    seqno = 0;

    log_messages.printf(MSG_NORMAL, "Starting\n");

    main_loop();
}
