// 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/>.

// validator - check and validate results, and grant credit
//  --app appname
//  [-d N] [--debug_level N]    log verbosity (1=least, 4=most)
//  [--one_pass_N_WU N]         Validate only N WU in one pass, then exit
//  [--one_pass]                make one pass through WU table, then exit
//  [--mod n i]                 process only WUs with (id mod n) == i
//  [--max_granted_credit X]    limit maximum granted credit to X
//  [--update_credited_job]     add userid/wuid pair to credited_job table
//
//  credit options.  The default is to grant credit using an
//  adaptive scheme that provides devices neutrality
//
//  [--no_credit]               don't grant credit
//                              Use this, e.g., if using trickles for credit
//  [--credit_from_wu]          get credit from WU XML
//  [--credit_from_runtime X]   grant credit based on runtime,
//                              assuming single-CPU app.
//                              X is the max runtime.

#include "config.h"
#include <unistd.h>
#include <climits>
#include <cmath>
#include <vector>
#include <cstdlib>
#include <string>
#include <signal.h>

#include "boinc_db.h"
#include "util.h"
#include "str_util.h"
#include "error_numbers.h"
#include "svn_version.h"
#include "common_defs.h"

#include "credit.h"
#include "sched_config.h"
#include "sched_util.h"
#include "sched_msgs.h"
#include "validator.h"
#include "validate_util.h"
#include "validate_util2.h"
#ifdef GCL_SIMULATOR
#include "gcl_simulator.h"
#endif

#define LOCKFILE "validate.out"
#define PIDFILE  "validate.pid"

#define SELECT_LIMIT    1000
#define SLEEP_PERIOD    5

int sleep_interval = SLEEP_PERIOD;

typedef enum {
    NEVER,
    DELAYED,
    IMMEDIATE,
    NO_CHANGE
} TRANSITION_TIME;

char app_name[256];
DB_APP app;
int wu_id_modulus=0;
int wu_id_remainder=0;
int one_pass_N_WU=0;
bool one_pass = false;
double max_granted_credit = 0;
bool update_credited_job = false;
bool credit_from_wu = false;
bool credit_from_runtime = false;
double max_runtime = 0;
bool no_credit = false;

WORKUNIT* g_wup;
vector<DB_APP_VERSION> app_versions;
    // cache of app_versions; used by v2 credit system

bool is_unreplicated(WORKUNIT& wu) {
    return (wu.target_nresults == 1 && app.target_nresults > 1);
}

// Here when a result has been validated.
// - update consecutive_valid
// - udpdate turnaround stats
// - insert credited_job record if needed
//
int is_valid(DB_HOST& host, RESULT& result, WORKUNIT& wu, DB_HOST_APP_VERSION& hav) {
    DB_CREDITED_JOB credited_job;
    int retval;

    double turnaround = result.received_time - result.sent_time;
    compute_avg_turnaround(host, turnaround);

    // increment daily quota
    //
    hav.max_jobs_per_day++;

    // increment consecutive_valid, but only if unreplicated
    //
    if (!is_unreplicated(wu)) {
        hav.consecutive_valid++;
        log_messages.printf(MSG_DEBUG,
            "[HAV#%d] consecutive valid now %d\n",
            hav.app_version_id, hav.consecutive_valid
        );
    }

    if (update_credited_job) {
        credited_job.userid = host.userid;
        credited_job.workunitid = long(wu.opaque);
        retval = credited_job.insert();
        if (retval) {
            log_messages.printf(MSG_CRITICAL,
                "[RESULT#%d] Warning: credited_job insert failed (userid: %d workunit: %f err: %s)\n",
                result.id, host.userid, wu.opaque, boincerror(retval)
            );
        } else {
            log_messages.printf(MSG_DEBUG,
                "[RESULT#%d %s] added credited_job record [WU#%d OPAQUE#%f USER#%d]\n",
                result.id, result.name, wu.id, wu.opaque, host.userid
            );
        }
    }

    return 0;
}

static inline void is_invalid(DB_HOST_APP_VERSION& hav) {
    hav.consecutive_valid = 0;
    if (hav.max_jobs_per_day > config.daily_result_quota) {
        hav.max_jobs_per_day--;
    }
}

// handle a workunit which has new results
//
int handle_wu(
    DB_VALIDATOR_ITEM_SET& validator, std::vector<VALIDATOR_ITEM>& items
) {
    int canonical_result_index = -1;
    bool update_result, retry;
    TRANSITION_TIME transition_time = NO_CHANGE;
    int retval = 0, canonicalid = 0, x;
    double credit = 0;
    unsigned int i;

    WORKUNIT& wu = items[0].wu;
    g_wup = &wu;

    if (wu.canonical_resultid) {
        log_messages.printf(MSG_NORMAL,
            "[WU#%d %s] Already has canonical result %d\n",
            wu.id, wu.name, wu.canonical_resultid
        );
        ++log_messages;

        // Here if WU already has a canonical result.
        // Get unchecked results and see if they match the canonical result
        //
        for (i=0; i<items.size(); i++) {
            RESULT& result = items[i].res;

            if (result.id == wu.canonical_resultid) {
                canonical_result_index = i;
            }
        }
        if (canonical_result_index == -1) {
            log_messages.printf(MSG_CRITICAL,
                "[WU#%d %s] Can't find canonical result %d\n",
                wu.id, wu.name, wu.canonical_resultid
            );
            return 0;
        }

        RESULT& canonical_result = items[canonical_result_index].res;

        // scan this WU's results, and check the unchecked ones
        //
        for (i=0; i<items.size(); i++) {
            RESULT& result = items[i].res;

            if (result.server_state != RESULT_SERVER_STATE_OVER) continue;
            if (result.outcome !=  RESULT_OUTCOME_SUCCESS) continue;
            switch (result.validate_state) {
            case VALIDATE_STATE_INIT:
            case VALIDATE_STATE_INCONCLUSIVE:
                break;
            default:
                continue;
            }
            log_messages.printf(MSG_NORMAL,
                 "[WU#%d] handle_wu(): testing result %d\n",
                 wu.id, result.id
             );

            check_pair(result, canonical_result, retry);
            if (retry) {
                // this usually means an NFS mount has failed;
                // arrange to try again later.
                //
                transition_time = DELAYED;
                goto leave;
            }
            update_result = false;

            if (result.outcome == RESULT_OUTCOME_VALIDATE_ERROR) {
                update_result = true;
            }

            // this might be last result, so let transitioner
            // trigger file delete etc. if needed
            //
            transition_time = IMMEDIATE;

            DB_HOST host;
            retval = host.lookup_id(result.hostid);
            if (retval) {
                log_messages.printf(MSG_CRITICAL,
                    "[RESULT#%d] lookup of host %d failed: %s\n",
                    result.id, result.hostid, boincerror(retval)
                );
                continue;
            }
            HOST host_initial = host;

            bool update_hav = false;
            DB_HOST_APP_VERSION hav;
            retval = hav_lookup(hav, result.hostid,
                generalized_app_version_id(result.app_version_id, result.appid)
            );
            if (retval) {
                hav.host_id = 0;
            }
            DB_HOST_APP_VERSION hav_orig = hav;
            vector<DB_HOST_APP_VERSION> havv;
            havv.push_back(hav);

            vector<RESULT> rv;
            switch (result.validate_state) {
            case VALIDATE_STATE_VALID:
                update_result = true;
                update_hav = true;
                log_messages.printf(MSG_NORMAL,
                    "[RESULT#%d %s] pair_check() matched: setting result to valid\n",
                    result.id, result.name
                );
                retval = is_valid(host, result, wu, havv[0]);
                if (retval) {
                    log_messages.printf(MSG_NORMAL,
                        "[RESULT#%d %s] is_valid() error: %s\n",
                        result.id, result.name, boincerror(retval)
                    );
                }
                // do credit computation, but grant credit of canonical result
                //
                rv.push_back(result);
                assign_credit_set(
                    wu, rv, app, app_versions, havv,
                    max_granted_credit, credit
                );
                if (!no_credit) {
                    result.granted_credit = canonical_result.granted_credit;
                    grant_credit(host, result.sent_time, result.granted_credit);
                }
                break;
            case VALIDATE_STATE_INVALID:
                update_result = true;
                update_hav = true;
                log_messages.printf(MSG_NORMAL,
                    "[RESULT#%d %s] pair_check() didn't match: setting result to invalid\n",
                    result.id, result.name
                );
                is_invalid(havv[0]);
            }
            if (hav.host_id && update_hav) {
                havv[0].update_validator(hav_orig);
            }
            host.update_diff_validator(host_initial);
            if (update_result) {
                log_messages.printf(MSG_NORMAL,
                    "[RESULT#%d %s] granted_credit %f\n",
                    result.id, result.name, result.granted_credit
                );

                retval = validator.update_result(result);
                if (retval) {
                    log_messages.printf(MSG_CRITICAL,
                        "[RESULT#%d %s] Can't update result: %s\n",
                        result.id, result.name, boincerror(retval)
                    );
                }
            }
        }
    } else {
        vector<RESULT> results;
        vector<DB_HOST_APP_VERSION> host_app_versions, host_app_versions_orig;
        int nsuccess_results;

        // Here if WU doesn't have a canonical result yet.
        // Try to get one

        log_messages.printf(MSG_NORMAL,
            "[WU#%d %s] handle_wu(): No canonical result yet\n",
            wu.id, wu.name
        );
        ++log_messages;

        // make a vector of the successful results,
        // and a parallel vector of host_app_versions
        //
        for (i=0; i<items.size(); i++) {
            RESULT& result = items[i].res;

            if ((result.server_state == RESULT_SERVER_STATE_OVER) &&
                (result.outcome == RESULT_OUTCOME_SUCCESS)
            ) {
                results.push_back(result);
                DB_HOST_APP_VERSION hav;
                retval = hav_lookup(hav, result.hostid,
                    generalized_app_version_id(result.app_version_id, result.appid)
                );
                if (retval) {
                    hav.host_id=0;   // flag that it's missing
                }
                host_app_versions.push_back(hav);
                host_app_versions_orig.push_back(hav);
            }
        }

        log_messages.printf(MSG_DEBUG,
            "[WU#%d %s] Found %d successful results\n",
            wu.id, wu.name, (int)results.size()
        );
        if (results.size() >= (unsigned int)wu.min_quorum) {
            log_messages.printf(MSG_DEBUG,
                "[WU#%d %s] Enough for quorum, checking set.\n",
                wu.id, wu.name
            );

            double dummy;
            retval = check_set(results, wu, canonicalid, dummy, retry);
            if (retval) {
                log_messages.printf(MSG_CRITICAL,
                    "[WU#%d %s] check_set() error: %s, exiting\n",
                    wu.id, wu.name, boincerror(retval)
                );
                return retval;
            }
            if (retry) transition_time = DELAYED;

            // if we found a canonical instance, decide on credit
            //
            if (canonicalid) {
                // always do the credit calculation, to update statistics,
                // even if we're granting credit a different way
                //
                retval = assign_credit_set(
                    wu, results, app, app_versions, host_app_versions,
                    max_granted_credit, credit
                );
                if (retval) {
                    log_messages.printf(MSG_CRITICAL,
                        "[WU#%d %s] assign_credit_set(): %s\n",
                        wu.id, wu.name, boincerror(retval)
                    );
                    transition_time = DELAYED;
                    goto leave;
                }

                if (credit_from_wu) {
                    retval = get_credit_from_wu(wu, results, credit);
                    if (retval) {
                        log_messages.printf(MSG_CRITICAL,
                            "[WU#%d %s] get_credit_from_wu(): credit not specified in WU\n",
                            wu.id, wu.name
                        );
                        credit = 0;
                    }
                } else if (credit_from_runtime) {
                    credit = 0;
                    for (i=0; i<results.size(); i++) {
                        RESULT& result = results[i];
                        if (result.id == canonicalid) {
                            DB_HOST host;
                            retval = host.lookup_id(result.hostid);
                            if (retval) {
                                log_messages.printf(MSG_CRITICAL,
                                    "[WU#%d %s] host %d lookup failed\n",
                                    wu.id, wu.name, result.hostid
                                );
                                break;
                            }
                            double runtime = result.elapsed_time;
                            if (runtime <=0 || runtime > max_runtime) {
                                runtime = max_runtime;
                            }
                            credit = result.flops_estimate * runtime * COBBLESTONE_SCALE;
                            log_messages.printf(MSG_NORMAL,
                                "[WU#%d][RESULT#%d] credit_from_runtime %.2f = %.0fs * %.2fGFLOPS\n",
                                wu.id, result.id,
                                credit, runtime, result.flops_estimate/1e9
                            );
                            break;
                        }
                    }
                } else if (no_credit) {
                    credit = 0;
                }
                if (max_granted_credit && credit>max_granted_credit) {
                    credit = max_granted_credit;
                }
            }

            // scan results.
            // update as needed, and count the # of results
            // that are still outcome=SUCCESS
            // (some may have changed to VALIDATE_ERROR)
            //
            nsuccess_results = 0;
            for (i=0; i<results.size(); i++) {
                RESULT& result = results[i];
                DB_HOST_APP_VERSION& hav = host_app_versions[i];
                DB_HOST_APP_VERSION& hav_orig = host_app_versions_orig[i];

                update_result = false;
                bool update_host = false;
                if (result.outcome == RESULT_OUTCOME_VALIDATE_ERROR) {
                    transition_time = IMMEDIATE;
                    update_result = true;
                } else {
                    nsuccess_results++;
                }

                DB_HOST host;
                HOST host_initial;
                switch (result.validate_state) {
                case VALIDATE_STATE_VALID:
                case VALIDATE_STATE_INVALID:
                    retval = host.lookup_id(result.hostid);
                    if (retval) {
                        log_messages.printf(MSG_CRITICAL,
                            "[RESULT#%d] lookup of host %d: %s\n",
                            result.id, result.hostid, boincerror(retval)
                        );
                        continue;
                    }
                    host_initial = host;
                }

                switch (result.validate_state) {
                case VALIDATE_STATE_VALID:
                    update_result = true;
                    update_host = true;
                    retval = is_valid(host, result, wu, host_app_versions[i]);
                    if (retval) {
                        log_messages.printf(MSG_DEBUG,
                            "[RESULT#%d %s] is_valid() failed: %s\n",
                            result.id, result.name, boincerror(retval)
                        );
                    }
                    if (!no_credit) {
                        result.granted_credit = credit;
                        grant_credit(host, result.sent_time, credit);
                        log_messages.printf(MSG_NORMAL,
                            "[RESULT#%d %s] Valid; granted %f credit [HOST#%d]\n",
                            result.id, result.name, result.granted_credit,
                            result.hostid
                        );
                    }
                    break;
                case VALIDATE_STATE_INVALID:
                    update_result = true;
                    update_host = true;
                    log_messages.printf(MSG_NORMAL,
                        "[RESULT#%d %s] Invalid [HOST#%d]\n",
                        result.id, result.name, result.hostid
                    );
                    is_invalid(host_app_versions[i]);
                    break;
                case VALIDATE_STATE_INIT:
                    log_messages.printf(MSG_NORMAL,
                        "[RESULT#%d %s] Inconclusive [HOST#%d]\n",
                        result.id, result.name, result.hostid
                    );
                    result.validate_state = VALIDATE_STATE_INCONCLUSIVE;
                    update_result = true;
                    break;
                }

                if (hav.host_id) {
                    retval = hav.update_validator(hav_orig);
                }
                if (update_host) {
                    retval = host.update_diff_validator(host_initial);
                }
                if (update_result) {
                    retval = validator.update_result(result);
                    if (retval) {
                        log_messages.printf(MSG_CRITICAL,
                            "[RESULT#%d %s] result.update() failed: %s\n",
                            result.id, result.name, boincerror(retval)
                        );
                    }
                }
            }

            if (canonicalid) {
                // if we found a canonical result,
                // trigger the assimilator, but do NOT trigger
                // the transitioner - doing so creates a race condition
                //
                transition_time = NEVER;
                log_messages.printf(MSG_DEBUG,
                    "[WU#%d %s] Found a canonical result: id=%d\n",
                    wu.id, wu.name, canonicalid
                );
                wu.canonical_resultid = canonicalid;
                wu.canonical_credit = credit;
                wu.assimilate_state = ASSIMILATE_READY;

                // don't need to send any more results
                //
                for (i=0; i<items.size(); i++) {
                    RESULT& result = items[i].res;

                    if (result.server_state != RESULT_SERVER_STATE_UNSENT) {
                        continue;
                    }

                    result.server_state = RESULT_SERVER_STATE_OVER;
                    result.outcome = RESULT_OUTCOME_DIDNT_NEED;
                    retval = validator.update_result(result);
                    if (retval) {
                        log_messages.printf(MSG_CRITICAL,
                            "[RESULT#%d %s] result.update() failed: %s\n",
                            result.id, result.name, boincerror(retval)
                        );
                    }
                }
            } else {
                // here if no consensus.

                // check if #success results is too large
                //
                if (nsuccess_results > wu.max_success_results) {
                    wu.error_mask |= WU_ERROR_TOO_MANY_SUCCESS_RESULTS;
                    transition_time = IMMEDIATE;
                }

                // if #success results >= target_nresults,
                // we need more results, so bump target_nresults
                // NOTE: nsuccess_results should never be > target_nresults,
                // but accommodate that if it should happen
                //
                if (nsuccess_results >= wu.target_nresults) {
                    wu.target_nresults = nsuccess_results+1;
                    transition_time = IMMEDIATE;
                }
            }
        }
    }

leave:
    --log_messages;

    switch (transition_time) {
    case IMMEDIATE:
        wu.transition_time = time(0);
        break;
    case DELAYED:
        x = time(0) + 6*3600;
        if (x < wu.transition_time) wu.transition_time = x;
        break;
    case NEVER:
        wu.transition_time = INT_MAX;
        break;
    case NO_CHANGE:
        break;
    }

    wu.need_validate = 0;
    
    retval = validator.update_workunit(wu);
    if (retval) {
        log_messages.printf(MSG_CRITICAL,
            "[WU#%d %s] update_workunit() failed: %s; exiting\n",
            wu.id, wu.name, boincerror(retval)
        );
        return retval;
    }
    return 0;
}

// make one pass through the workunits with need_validate set.
// return true if there were any
//
bool do_validate_scan() {
    DB_VALIDATOR_ITEM_SET validator;
    std::vector<VALIDATOR_ITEM> items;
    bool found=false;
    int retval, i=0;

    // loop over entries that need to be checked
    //
    while (1) {
        retval = validator.enumerate(
            app.id, SELECT_LIMIT, wu_id_modulus, wu_id_remainder, items
        );
        if (retval) {
            if (retval != ERR_DB_NOT_FOUND) {
                log_messages.printf(MSG_DEBUG,
                    "DB connection lost, exiting\n"
                );
                exit(0);
            }
            break;
        }
        retval = handle_wu(validator, items);
        if (!retval) found = true;
        if (++i == one_pass_N_WU) break;
    }
    return found;
}

int main_loop() {
    int retval;
    bool did_something;
    char buf[256];

    sprintf(buf, "where name='%s'", app_name);

    while (1) {
        check_stop_daemons();

        // look up app within the loop,
        // in case its min_avg_pfc has been changed by the feeder
        //
        retval = app.lookup(buf);
        if (retval) {
            log_messages.printf(MSG_CRITICAL, "can't find app %s\n", app_name);
            exit(1);
        }
        did_something = do_validate_scan();
        if (!did_something) {
            write_modified_app_versions(app_versions);
            if (one_pass) break;
#ifdef GCL_SIMULATOR
            char nameforsim[64];
            sprintf(nameforsim, "validator%i", app.id);
            continue_simulation(nameforsim);
            signal(SIGUSR2, simulator_signal_handler);
            pause();
#else
            sleep(sleep_interval);
#endif
        }
    }
    return 0;
}

// For use by project-supplied routines check_set() and check_match()
//
int debug_level=0;

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

    const char *usage = 
      "\nUsage: %s --app <app-name> [OPTIONS]\n"
      "Start validator for application <app-name>\n\n"
      "Optional arguments:\n"
      "  --one_pass_N_WU N       Validate at most N WUs, then exit\n"
      "  --one_pass              Make one pass through WU table, then exit\n"
      "  --mod n i               Process only WUs with (id mod n) == i\n"
      "  --max_granted_credit X  Grant no more than this amount of credit to a result\n"
      "  --update_credited_job   Add record to credited_job table after granting credit\n"
      "  --credit_from_wu        Credit is specified in WU XML\n"
      "  --credit_from_runtime X  Grant credit based on runtime (max X seconds)and estimated FLOPS\n"
      "  --no_credit             Don't grant credit\n"
      "  --sleep_interval n      Set sleep-interval to n\n"
      "  -d n, --debug_level n   Set log verbosity level, 1-4\n"
      "  -h | --help             Show this\n"
      "  -v | --version          Show version information\n";

    if ((argc > 1) && (!strcmp(argv[1], "-h") || !strcmp(argv[1], "--help"))) {
        printf (usage, argv[0] );
        exit(0);
    }

    check_stop_daemons();

    for (i=1; i<argc; i++) {
        if (is_arg(argv[i], "one_pass_N_WU")) {
            one_pass_N_WU = atoi(argv[++i]);
            one_pass = true;
        } else if (is_arg(argv[i], "sleep_interval")) {
            sleep_interval = atoi(argv[++i]);
        } else if (is_arg(argv[i], "one_pass")) {
            one_pass = true;
        } else if (is_arg(argv[i], "app")) {
            strcpy(app_name, argv[++i]);
        } else if (is_arg(argv[i], "d") || is_arg(argv[i], "debug_level")) {
            debug_level = atoi(argv[++i]);
            log_messages.set_debug_level(debug_level);
            if (debug_level == 4) g_print_queries = true;
        } else if (is_arg(argv[i], "mod")) {
            wu_id_modulus = atoi(argv[++i]);
            wu_id_remainder = atoi(argv[++i]);
        } else if (is_arg(argv[i], "max_granted_credit")) {
            max_granted_credit = atof(argv[++i]);
        } else if (is_arg(argv[i], "update_credited_job")) {
            update_credited_job = true;
        } else if (is_arg(argv[i], "credit_from_wu")) {
            credit_from_wu = true;
        } else if (is_arg(argv[i], "credit_from_runtime")) {
            credit_from_runtime = true;
            max_runtime = atof(argv[++i]);
        } else if (is_arg(argv[i], "no_credit")) {
            no_credit = true;
        } else if (is_arg(argv[i], "v") || is_arg(argv[i], "version")) {
            printf("%s\n", SVN_VERSION);
            exit(0);
        } else {
            fprintf(stderr,
                "Invalid option '%s'\nTry `%s --help` for more information\n",
                argv[i], argv[0]
            );
            log_messages.printf(MSG_CRITICAL, "unrecognized arg: %s\n", argv[i]);
            exit(1);
        }
    }

    if (app_name[0] == 0) {
        log_messages.printf(MSG_CRITICAL,
            "must use '--app' to specify an application\n"
        );
        printf (usage, argv[0] );
        exit(1);      
    }

    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,
            "boinc_db.open failed: %s\n", boincerror(retval)
        );
        exit(1);
    }

    log_messages.printf(MSG_NORMAL,
        "Starting validator, debug level %d\n", log_messages.debug_level
    );

    if (credit_from_runtime) {
        log_messages.printf(MSG_NORMAL,
            "using credit from runtime, max runtime: %f\n", max_runtime
        );
    }

    if (wu_id_modulus) {
        log_messages.printf(MSG_NORMAL,
            "Modulus %d, remainder %d\n", wu_id_modulus, wu_id_remainder
        );
    }

    install_stop_signal_handler();

    main_loop();
}

const char *BOINC_RCSID_634dbda0b9 = "$Id$";