// Berkeley Open Infrastructure for Network Computing
// http://boinc.berkeley.edu
// Copyright (C) 2006 University of California
//
// This 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 2.1 of the License, or (at your option) any later version.
//
// This software 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.
//
// To view the GNU Lesser General Public License visit
// http://www.gnu.org/copyleft/lesser.html
// or write to the Free Software Foundation, Inc.,
// 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

// BOINC client simulator.
//
// usage:
// sim [--duration x] [--delta x] [--dirs dir ...]
//  duration = simulation duration (default 86400)
//  delta = simulation time step (default 10)
//
// If no dirs are specified:
// reads input files
//    sim_projects.xml, sim_host.xml, sim_prefs.xml, cc_config.xml
// and does simulation, generating output files
//    sim_log.txt, sim_out.html
//
// If dirs are specified, chdir into each directory in sequence,
// do the above for each one, and write summary info to stdout

#include "error_numbers.h"
#include "str_util.h"
#include "log_flags.h"
#include "filesys.h"
#include "network.h"
#include "client_msgs.h"
#include "sim.h"

CLIENT_STATE gstate;
NET_STATUS net_status;
bool g_use_sandbox;
bool user_active;
double duration = 86400, delta = 60;
FILE* logfile;
bool running;

SIM_RESULTS sim_results;

//////////////// FUNCTIONS MODIFIED OR STUBBED OUT /////////////

CLIENT_STATE::CLIENT_STATE() {
    initialized = false;
}

FILE* boinc_fopen(const char* path, const char* mode) {
    return fopen(path, mode);
}

void CLIENT_STATE::set_client_state_dirty(char const*) {
}

void HOST_INFO::generate_host_cpid() {}

int get_connected_state() {return CONNECTED_STATE_CONNECTED;}

int CLIENT_STATE::report_result_error(RESULT& , const char* , ...) {return 0;}

void show_message(PROJECT *p, char* msg, int priority) {
    const char* x;
    char message[1024];
    char* time_string = time_to_string(gstate.now);

    if (priority == MSG_INTERNAL_ERROR) {
        strcpy(message, "[error] ");
        strlcpy(message+8, msg, sizeof(message)-8);
    } else {
        strlcpy(message, msg, sizeof(message));
    }
    while (strlen(message)&&message[strlen(message)-1] == '\n') {
        message[strlen(message)-1] = 0;
    }

    if (p) {
        x = p->get_project_name();
    } else {
        x = "---";
    }

    fprintf(logfile, "%s [%s] %s\n", time_string, x, message);
}
bool RESULT::some_download_stalled() {
    return false;
}
bool PROJECT::some_download_stalled() {
    return false;
}

APP_CLIENT_SHM::APP_CLIENT_SHM() {}
GRAPHICS_MSG::GRAPHICS_MSG() {}
HOST_INFO::HOST_INFO() {}

//////////////// FUNCTIONS COPIED /////////////

void SIM_PROJECT::init() {
    strcpy(master_url, "");
    strcpy(authenticator, "");
    project_specific_prefs = "";
    gui_urls = "";
    resource_share = 100;
    strcpy(host_venue, "");
    using_venue_specific_prefs = false;
    scheduler_urls.clear();
    strcpy(project_name, "");
    strcpy(symstore, "");
    strcpy(user_name, "");
    strcpy(team_name, "");
    strcpy(email_hash, "");
    strcpy(cross_project_id, "");
    user_total_credit = 0;
    user_expavg_credit = 0;
    user_create_time = 0;
    ams_resource_share = 0;
    rpc_seqno = 0;
    hostid = 0;
    host_total_credit = 0;
    host_expavg_credit = 0;
    host_create_time = 0;
    nrpc_failures = 0;
    master_fetch_failures = 0;
    min_rpc_time = 0;
	possibly_backed_off = true;
    master_url_fetch_pending = false;
    sched_rpc_pending = 0;
    next_rpc_time = 0;
    last_rpc_time = 0;
    trickle_up_pending = false;
    tentative = false;
    anonymous_platform = false;
    non_cpu_intensive = false;
    verify_files_on_app_start = false;
    short_term_debt = 0;
    long_term_debt = 0;
    send_file_list = false;
    suspended_via_gui = false;
    dont_request_more_work = false;
    detach_when_done = false;
    attached_via_acct_mgr = false;
    strcpy(code_sign_key, "");
    user_files.clear();
    project_files.clear();
    anticipated_debt = 0;
    wall_cpu_time_this_debt_interval = 0;
    next_runnable_result = NULL;
    work_request = 0;
    work_request_urgency = WORK_FETCH_DONT_NEED;
    duration_correction_factor = 1;
    project_files_downloaded_time = 0;

    // Initialize scratch variables.
    rrsim_proc_rate = 0.0;
    cpu_shortfall = 0.0;
    rr_sim_deadlines_missed = 0;
    deadlines_missed = 0;

    idle_period_duration = 0;
    idle_period_sumsq = 0;
}

void RESULT::clear() {
    strcpy(name, "");
    strcpy(wu_name, "");
    report_deadline = 0;
    output_files.clear();
    _state = RESULT_NEW;
    ready_to_report = false;
    completed_time = 0;
    got_server_ack = false;
    final_cpu_time = 0;
    exit_status = 0;
    stderr_out = "";
    suspended_via_gui = false;
    rr_sim_misses_deadline = false;
    last_rr_sim_missed_deadline = false;
    fpops_per_cpu_sec = 0;
    fpops_cumulative = 0;
    intops_per_cpu_sec = 0;
    intops_cumulative = 0;
    app = NULL;
    wup = NULL;
    project = NULL;
}

static const char* task_state_name(int val) {
    switch (val) {
    case PROCESS_UNINITIALIZED: return "UNINITIALIZED";
    case PROCESS_EXECUTING: return "EXECUTING";
    case PROCESS_SUSPENDED: return "SUSPENDED";
    case PROCESS_ABORT_PENDING: return "ABORT_PENDING";
    case PROCESS_EXITED: return "EXITED";
    case PROCESS_WAS_SIGNALED: return "WAS_SIGNALED";
    case PROCESS_EXIT_UNKNOWN: return "EXIT_UNKNOWN";
    case PROCESS_ABORTED: return "ABORTED";
    case PROCESS_COULDNT_START: return "COULDNT_START";
    case PROCESS_QUIT_PENDING: return "QUIT_PENDING";
    }
    return "Unknown";
}

void ACTIVE_TASK::set_task_state(int val, const char* where) {
    _task_state = val;
    if (log_flags.task_debug) {
        msg_printf(result->project, MSG_INFO,
            "[task_debug] task_state=%s for %s from %s",
            task_state_name(val), result->name, where
        );
    }
}

char* PROJECT::get_project_name() {
    if (strlen(project_name)) {
        return project_name;
    } else {
        return master_url;
    }
}

static inline double drand() {
    return (double)rand()/(double)RAND_MAX;
}

// return a random double in the range [rmin,rmax)

static inline double rand_range(double rmin, double rmax) {
    if (rmin < rmax) {
        return drand() * (rmax-rmin) + rmin;
    } else {
        return rmin;
    }
}

// return a random double in the range [MIN,min(e^n,MAX))
//
double calculate_exponential_backoff( int n, double MIN, double MAX) {
    double rmax = std::min(MAX, exp((double)n));
    return rand_range(MIN, rmax);
}

// amount of RAM usable now
//
double CLIENT_STATE::available_ram() {
    if (user_active) {
        return host_info.m_nbytes * global_prefs.ram_max_used_busy_frac;
    } else {
		return host_info.m_nbytes * global_prefs.ram_max_used_idle_frac;
    }
}

// max amount that will ever be usable
//
double CLIENT_STATE::max_available_ram() {
	return host_info.m_nbytes*std::max(
		global_prefs.ram_max_used_busy_frac, global_prefs.ram_max_used_idle_frac
	);
}

RESULT* CLIENT_STATE::lookup_result(PROJECT* p, const char* name) {
    for (unsigned int i=0; i<results.size(); i++) {
        RESULT* rp = results[i];
        if (rp->project == p && !strcmp(name, rp->name)) return rp;
    }
    return 0;
}

bool CLIENT_STATE::simulate_rpc(PROJECT* _p) {
    double net_fpops = host_info.p_fpops;
    char buf[256];
    SIM_PROJECT* p = (SIM_PROJECT*) _p;
    static double last_time=0;

    double diff = now - last_time;
    if (diff && diff < host_info.connection_interval) {
        return false;
    }
    last_time = now;

    sprintf(buf, "RPC to %s; asking for %f<br>", p->project_name, p->work_request);
    html_msg += buf;

    // remove ready-to-report results
    //
    vector<RESULT*>::iterator result_iter;
    result_iter = results.begin();
    while (result_iter != results.end()) {
        RESULT* rp = *result_iter;
        if (rp->ready_to_report) {
            sprintf(buf, "result %s reported; %s<br>",
                rp->name,
                (gstate.now > rp->report_deadline)?
                "<font color=#cc0000>MISSED DEADLINE</font>":
                "<font color=#00cc00>MADE DEADLINE</font>"
            );
            SIM_PROJECT* spp = (SIM_PROJECT*)rp->project;
            if (gstate.now > rp->report_deadline) {
                sim_results.cpu_wasted += rp->final_cpu_time;
                sim_results.nresults_missed_deadline++;
                spp->project_results.nresults_missed_deadline++;
                spp->project_results.cpu_wasted += rp->final_cpu_time;
            } else {
                sim_results.cpu_used += rp->final_cpu_time;
                sim_results.nresults_met_deadline++;
                spp->project_results.nresults_met_deadline++;
                spp->project_results.cpu_used += rp->final_cpu_time;
            }
            gstate.html_msg += buf;
            delete rp;
            result_iter = results.erase(result_iter);
        } else {
            result_iter++;
        }
    }

    while (p->work_request > 0) {
        // pick a random app
        SIM_APP* ap1, *ap=0;
        double x = drand();
        for (unsigned int i=0; i<apps.size();i++) {
            ap1 = (SIM_APP*)apps[i];
            if (ap1->project != p) continue;
            x -= ap1->weight;
            if (x <= 0) {
                ap = ap1;
                break;
            }
        }
        if (!ap) {
            printf("ERROR-NO APP\n");
            break;
        }
        RESULT* rp = new RESULT;
        WORKUNIT* wup = new WORKUNIT;
        rp->clear();
        rp->project = p;
        rp->wup = wup;
        sprintf(rp->name, "%s_%d", p->project_name, p->result_index++);
        rp->set_state(RESULT_FILES_DOWNLOADED, "simulate_rpc");
        wup->project = p;
        wup->rsc_fpops_est = ap->fpops_est;
        results.push_back(rp);
        double ops = ap->fpops.sample();
        rp->final_cpu_time = ops/net_fpops;
        rp->report_deadline = now + ap->latency_bound;
        sprintf(buf, "got job %s: CPU time %.2f, deadline %s<br>",
            rp->name, rp->final_cpu_time, time_to_string(rp->report_deadline)
        );
        html_msg += buf;
        p->work_request -= ap->fpops_est/net_fpops;
    }
    p->work_request = 0;
    request_schedule_cpus("simulate_rpc");
    request_work_fetch("simulate_rpc");
    return true;
}

bool CLIENT_STATE::scheduler_rpc_poll() {
    PROJECT *p;

    p = next_project_sched_rpc_pending();
    if (p) {
        return simulate_rpc(p);
    }
    
    p = find_project_with_overdue_results();
    if (p) {
        return simulate_rpc(p);
    }
    p = next_project_need_work();
    if (p) {
        return simulate_rpc(p);
    }
    return false;
}

bool ACTIVE_TASK_SET::poll() {
    unsigned int i;
    char buf[256];
    bool action = false;
    static double last_time = 0;
    double diff = gstate.now - last_time;
    if (diff < 1.0) return false;
    last_time = gstate.now;
    SIM_PROJECT* p;

    if (!running) return false;

    for (i=0; i<gstate.projects.size(); i++) {
        p = (SIM_PROJECT*) gstate.projects[i];
        p->idle = true;
    }

    int n=0;
    for (i=0; i<active_tasks.size(); i++) {
        ACTIVE_TASK* atp = active_tasks[i];
        switch (atp->task_state()) {
        case PROCESS_EXECUTING:
            atp->cpu_time_left -= diff;
            RESULT* rp = atp->result;

            double cpu_time_used = rp->final_cpu_time - atp->cpu_time_left;
            atp->fraction_done = cpu_time_used/rp->final_cpu_time;
            atp->checkpoint_wall_time = gstate.now;

            if (atp->cpu_time_left <= 0) {
                atp->set_task_state(PROCESS_EXITED, "poll");
                rp->exit_status = 0;
                rp->ready_to_report = true;
                gstate.request_schedule_cpus("ATP poll");
                gstate.request_work_fetch("ATP poll");
                sprintf(buf, "result %s finished<br>", rp->name);
                gstate.html_msg += buf;
            }
            ((SIM_PROJECT*)rp->project)->idle = false;
            n++;
        }
    }
    if (n < gstate.ncpus) {
        sim_results.cpu_idle += diff*(gstate.ncpus-n);
    }
    if (n > gstate.ncpus) {
        sprintf(buf, "TOO MANY JOBS RUNNING");
        gstate.html_msg += buf;
    }

    for (i=0; i<gstate.projects.size(); i++) {
        p = (SIM_PROJECT*) gstate.projects[i];
        if (p->idle) {
            p->idle_period_duration += diff;
        } else {
            p->idle_period_duration = 0;
        }
        double ipd = p->idle_period_duration;
        p->idle_period_sumsq += ipd*ipd;
        p->nidle_periods++;
    }

    return action;
}

//////////////// FUNCTIONS WE NEED TO IMPLEMENT /////////////

ACTIVE_TASK::ACTIVE_TASK() {
}

int ACTIVE_TASK::suspend() {
    if (task_state() != PROCESS_EXECUTING) {
        msg_printf(0, MSG_INFO, "Internal error: expected process to be executing");
    }
    set_task_state(PROCESS_SUSPENDED, "suspend");
    return 0;
}

int ACTIVE_TASK::request_exit() {
    set_task_state(PROCESS_UNINITIALIZED, "request_exit");
    return 0;
}

int ACTIVE_TASK::resume_or_start(bool first_time) {
    if (log_flags.task) {
        msg_printf(result->project, MSG_INFO,
            "[task] %s task %s",
            first_time?"Starting":"Resuming", result->name
        );
    }
    set_task_state(PROCESS_EXECUTING, "start");
    char buf[256];
    sprintf(buf, "Starting %s: %f<br>", result->name, cpu_time_left);
    gstate.html_msg += buf;
    return 0;
}

int ACTIVE_TASK_SET::get_free_slot(){
    return 0;
}
int ACTIVE_TASK::init(RESULT* rp) {
    result = rp;
    wup = rp->wup;
    app_version = wup->avp;
    max_cpu_time = rp->wup->rsc_fpops_bound/gstate.host_info.p_fpops;
    max_disk_usage = rp->wup->rsc_disk_bound;
    max_mem_usage = rp->wup->rsc_memory_bound;
    cpu_time_left = rp->final_cpu_time;
    _task_state = PROCESS_UNINITIALIZED;
    scheduler_state = CPU_SCHED_UNINITIALIZED;
    return 0;
}

void CLIENT_STATE::print_project_results(FILE* f) {
    for (unsigned int i=0; i<projects.size(); i++) {
        SIM_PROJECT* p = (SIM_PROJECT*) projects[i];
        p->print_results(f, sim_results);
    }
}


//////////////// OTHER

PROJECT::PROJECT() {
}

// http://www.cs.wm.edu/~va/software/park/rvgs.c
double NORMAL_DIST::sample() {
  const double p0 = 0.322232431088;     const double q0 = 0.099348462606;
  const double p1 = 1.0;                const double q1 = 0.588581570495;
  const double p2 = 0.342242088547;     const double q2 = 0.531103462366;
  const double p3 = 0.204231210245e-1;  const double q3 = 0.103537752850;
  const double p4 = 0.453642210148e-4;  const double q4 = 0.385607006340e-2;
  double u, t, p, q, z;

  u   = drand();
  if (u < 0.5)
    t = sqrt(-2.0 * log(u));
  else
    t = sqrt(-2.0 * log(1.0 - u));
  p   = p0 + t * (p1 + t * (p2 + t * (p3 + t * p4)));
  q   = q0 + t * (q1 + t * (q2 + t * (q3 + t * q4)));
  if (u < 0.5)
    z = (p / q) - t;
  else
    z = t - (p / q);
  return (mean + stdev * z);

}

inline double exponential(double mean) {
    return -mean*log(1-drand());
}

bool RANDOM_PROCESS::sample(double t) {
    if (frac==1) return true;
    double diff = t-last_time;
    last_time = t;
    time_left -= diff;
    if (time_left < 0) {
        if (value) {
            time_left += exponential(off_lambda);
            value = false;
        } else {
            time_left += exponential(lambda);
            value = true;
        }
    }
    return value;
}

RANDOM_PROCESS::RANDOM_PROCESS() {
    frac = 1;
}

void RANDOM_PROCESS::init() {
    value = true;
    time_left = exponential(lambda);
    off_lambda = lambda/frac - lambda;
}

int NORMAL_DIST::parse(XML_PARSER& xp, char* end_tag) {
    char tag[256];
    bool is_tag;
    while(!xp.get(tag, sizeof(tag), is_tag)) {
        if (!is_tag) return ERR_XML_PARSE;
        if (xp.parse_double(tag, "mean", mean)) continue;
        else if (xp.parse_double(tag, "stdev", stdev)) continue;
        else if (!strcmp(tag, end_tag)) return 0;
        else {
            printf("unrecognized: %s\n", tag);
            return ERR_XML_PARSE;
        }
    }
    return ERR_XML_PARSE;
}

int UNIFORM_DIST::parse(XML_PARSER& xp, char* end_tag) {
    char tag[256];
    bool is_tag;
    while(!xp.get(tag, sizeof(tag), is_tag)) {
        if (!is_tag) return ERR_XML_PARSE;
        if (xp.parse_double(tag, "lo", lo)) continue;
        else if (xp.parse_double(tag, "hi", hi)) continue;
        else if (!strcmp(tag, end_tag)) return 0;
        else {
            printf("unrecognized: %s\n", tag);
            return ERR_XML_PARSE;
        }
    }
    return ERR_XML_PARSE;
}

int RANDOM_PROCESS::parse(XML_PARSER& xp, char* end_tag) {
    char tag[256];
    bool is_tag;
    while(!xp.get(tag, sizeof(tag), is_tag)) {
        if (!is_tag) return ERR_XML_PARSE;
        if (xp.parse_double(tag, "frac", frac)) continue;
        else if (xp.parse_double(tag, "lambda", lambda)) continue;
        else if (!strcmp(tag, end_tag)) return 0;
        else {
            printf("unrecognized: %s\n", tag);
            return ERR_XML_PARSE;
        }
    }
    return ERR_XML_PARSE;
}

int SIM_APP::parse(XML_PARSER& xp) {
    char tag[256];
    bool is_tag;
    int retval;

    weight = 1;
    while(!xp.get(tag, sizeof(tag), is_tag)) {
        if (!is_tag) return ERR_XML_PARSE;
        if (!strcmp(tag, "/app")) {
            return 0;
        }
        else if (xp.parse_double(tag, "latency_bound", latency_bound)) continue;
        else if (xp.parse_double(tag, "fpops_est", fpops_est)) continue;
        else if (xp.parse_double(tag, "weight", weight)) continue;
        else if (!strcmp(tag, "fpops")) {
            retval = fpops.parse(xp, "/fpops");
            if (retval) return retval;
        } else if (!strcmp(tag, "checkpoint_period")) {
            retval = checkpoint_period.parse(xp, "/checkpoint_period");
            if (retval) return retval;
        } else if (xp.parse_double(tag, "working_set", working_set)) continue;
        else {
            printf("unrecognized: %s\n", tag);
            return ERR_XML_PARSE;
        }
    }
    return ERR_XML_PARSE;
}

// return the fraction of CPU time that was spent in violation of shares
// i.e., if a project got X and it should have got Y,
// add up |X-Y| over all projects, and divide by total CPU
//
double CLIENT_STATE::share_violation() {
    double x = 0;
    unsigned int i;

    double tot = 0, trs=0;
    for (i=0; i<projects.size(); i++) {
        SIM_PROJECT* p = (SIM_PROJECT*) projects[i];
        tot += p->project_results.cpu_used + p->project_results.cpu_wasted;
        trs += p->resource_share;
    }
    double sum = 0;
    for (i=0; i<projects.size(); i++) {
        SIM_PROJECT* p = (SIM_PROJECT*) projects[i];
        double t = p->project_results.cpu_used + p->project_results.cpu_wasted;
        double rs = p->resource_share/trs;
        double rt = tot*rs;
        sum += fabs(t - rt);
    }
    return sum/tot;

}

// "variety" is defined as the RMS of the duration of idle periods
// across all projects
//
double CLIENT_STATE::variety() {
    double sum = 0;
    int n = 0;
    unsigned int i;
    for (i=0; i<projects.size(); i++) {
        SIM_PROJECT* p = (SIM_PROJECT*) projects[i];
        sum += p->idle_period_sumsq;
        n += p->nidle_periods;
    }
    return sqrt(sum/n);
}

void SIM_RESULTS::compute() {
    double total = cpu_used + cpu_wasted + cpu_idle;
    cpu_wasted_frac = cpu_wasted/total;
    cpu_idle_frac = cpu_idle/total;
    share_violation = gstate.share_violation();
    variety = gstate.variety();
}

// top-level results (for aggregating multiple simulations)
//
void SIM_RESULTS::print(FILE* f, const char* title) {
    if (title) {
        fprintf(f, title);
    }
    fprintf(f, "wasted %f idle %f share_violation %f variety %f\n",
        cpu_wasted_frac, cpu_idle_frac, share_violation, variety
    );
}

void SIM_RESULTS::parse(FILE* f) {
    fscanf(f, "wasted %lf idle %lf share_violation %lf variety %lf",
        &cpu_wasted, &cpu_idle, &share_violation, &variety
    );
}
void SIM_RESULTS::add(SIM_RESULTS& r) {
    cpu_used += r.cpu_used;
    cpu_wasted += r.cpu_wasted;
    cpu_idle += r.cpu_idle;
    nresults_met_deadline += r.nresults_met_deadline;
    nresults_missed_deadline += r.nresults_missed_deadline;
}

SIM_RESULTS::SIM_RESULTS() {
    cpu_used = 0; cpu_wasted=0; cpu_idle=0;
    nresults_met_deadline = 0; nresults_missed_deadline = 0;
}

void SIM_PROJECT::print_results(FILE* f, SIM_RESULTS& sr) {
    double t = project_results.cpu_used + project_results.cpu_wasted;
    double gt = sr.cpu_used + sr.cpu_wasted;
    fprintf(f, "%s: share %.2f total CPU %2f (%.2f%%)\n"
        "   used %.2f wasted %.2f\n"
        "   met %d missed %d\n",
        project_name, resource_share,
        t, (t/gt)*100,
        project_results.cpu_used,
        project_results.cpu_wasted,
        project_results.nresults_met_deadline,
        project_results.nresults_missed_deadline
    );
}

int SIM_PROJECT::parse(XML_PARSER& xp) {
    char tag[256];
    bool is_tag;
    int retval;

    while(!xp.get(tag, sizeof(tag), is_tag)) {
        if (!is_tag) return ERR_XML_PARSE;
        if (!strcmp(tag, "/project")) return 0;
        else if (xp.parse_str(tag, "project_name", project_name, sizeof(project_name))) continue;
        else if (!strcmp(tag, "app")) {
            SIM_APP* sap = new SIM_APP;
            retval = sap->parse(xp);
            if (retval) return retval;
            sap->project = this;
            gstate.apps.push_back(sap);
        } else if (!strcmp(tag, "available")) {
            retval = available.parse(xp, "/available");
            if (retval) return retval;
        } else if (xp.parse_double(tag, "resource_share", resource_share)) {
            continue;
        } else {
            printf("unrecognized: %s\n", tag);
            return ERR_XML_PARSE;
        }
    }
    return ERR_XML_PARSE;
}

int SIM_HOST::parse(XML_PARSER& xp) {
    char tag[256];
    bool is_tag;
    int retval;

    p_ncpus = 1;
    connection_interval = 0;
    while(!xp.get(tag, sizeof(tag), is_tag)) {
        if (!is_tag) return ERR_XML_PARSE;
        if (!strcmp(tag, "/host")) return 0;
        else if (xp.parse_double(tag, "p_fpops", p_fpops)) continue;
        else if (xp.parse_double(tag, "m_nbytes", m_nbytes)) continue;
        else if (xp.parse_double(tag, "connection_interval", connection_interval)) continue;
        else if (xp.parse_int(tag, "p_ncpus", p_ncpus)) continue;
        else if (!strcmp(tag, "available")) {
            retval = available.parse(xp, "/available");
            if (retval) return retval;
            available.init();
        } else if (!strcmp(tag, "idle")) {
            retval = idle.parse(xp, "/idle");
            if (retval) return retval;
            idle.init();
        } else {
            printf("unrecognized: %s\n", tag);
            return ERR_XML_PARSE;
        }
    }       
    return ERR_XML_PARSE;
}

int CLIENT_STATE::parse_projects(char* name) {
    char tag[256];
    bool is_tag;
    MIOFILE mf;
    int retval, index=0;

    FILE* f = fopen(name, "r");
    if (!f) return ERR_FOPEN;
    mf.init_file(f);
    XML_PARSER xp(&mf);
    if (!xp.parse_start("projects")) return ERR_XML_PARSE;
    while(!xp.get(tag, sizeof(tag), is_tag)) {
        if (!is_tag) return ERR_XML_PARSE;
        if (!strcmp(tag, "project")) {
            SIM_PROJECT *p = new SIM_PROJECT;
            p->init();
            retval = p->parse(xp);
            if (retval) return retval;
            p->index = index++;
            p->result_index = 0;
            projects.push_back(p);
        } else if (!strcmp(tag, "/projects")) {
            return 0;
        } else {
            printf("unrecognized: %s\n", tag);
            return ERR_XML_PARSE;
        }
    }
    return ERR_XML_PARSE;
}

int CLIENT_STATE::parse_host(char* name) {
    MIOFILE mf;

    FILE* f = fopen(name, "r");
    if (!f) return ERR_FOPEN;
    mf.init_file(f);
    XML_PARSER xp(&mf);
    if (!xp.parse_start("host")) return ERR_XML_PARSE;
    return host_info.parse(xp);
}

char* colors[] = {
    "#ffffdd",
    "#ffddff",
    "#ddffff",
    "#ddffdd",
    "#ddddff",
    "#ffdddd",
};

void CLIENT_STATE::html_start() {
    html_out = fopen("sim_out.html", "w");
    fprintf(html_out, "<h2>Simulator output</h2>"
        "<a href=sim_log.txt>message log</a><p>"
        "<table border=1>\n"
    );
}

void CLIENT_STATE::html_rec() {
    fprintf(html_out, "<tr><td>%s</td>", time_to_string(now));

    if (!running) {
        for (int j=0; j<ncpus; j++) {
            fprintf(html_out, "<td bgcolor=#888888><br></td>");
        }
    } else {
        int n=0;
        for (unsigned int i=0; i<active_tasks.active_tasks.size(); i++) {
            ACTIVE_TASK* atp = active_tasks.active_tasks[i];
            if (atp->task_state() == PROCESS_EXECUTING) {
                SIM_PROJECT* p = (SIM_PROJECT*)atp->result->project;
                fprintf(html_out, "<td bgcolor=%s>%s: %.2f</td>",
                colors[p->index], atp->result->name, atp->cpu_time_left);
                n++;
            }
        }
        while (n<ncpus) {
            fprintf(html_out, "<td><br></td>");
            n++;
        }
    }
    fprintf(html_out, "<td><font size=-2>%s</font></td></tr>\n", html_msg.c_str());
    html_msg = "";
}

void CLIENT_STATE::html_end() {
    double cpu_total=sim_results.cpu_used + sim_results.cpu_wasted + sim_results.cpu_idle;
    fprintf(html_out, "</table><pre>\n");
    sim_results.compute();
    sim_results.print(html_out);
    print_project_results(html_out);
    fprintf(html_out, "</pre>\n");
    fclose(html_out);
}

void CLIENT_STATE::simulate() {
    bool action;
    now = 0;
    html_start();
    while (1) {
        running = host_info.available.sample(now);
        while (1) {
            action = active_tasks.poll();
            if (running) {
                action |= handle_finished_apps();
                action |= possibly_schedule_cpus();
                action |= enforce_schedule();
                action |= compute_work_requests();
                action |= scheduler_rpc_poll();
            }
            if (!action) break;
        }
        now += delta;
        html_rec();
        if (now > duration) break;
    }
    html_end();
}

void parse_error(char* file, int retval) {
    printf("can't parse %s: %d\n", file, retval);
    exit(1);
}

void help(char* prog) {
    fprintf(stderr, "usage: %s [--duration X] [--delta X]\n", prog);
    exit(1);
}

char* next_arg(int argc, char** argv, int& i) {
    if (i >= argc) {
        fprintf(stderr, "Missing command-line argument\n");
        help(argv[0]);
    }
    return argv[i++];
}

#define PROJECTS_FILE "sim_projects.xml"
#define HOST_FILE "sim_host.xml"
#define PREFS_FILE "sim_prefs.xml"
#define SUMMARY_FILE "sim_summary.txt"
#define LOG_FILE "sim_log.txt"

int main(int argc, char** argv) {
    int i, retval;
    vector<std::string> dirs;

    logfile = fopen("sim_log.txt", "w");

    for (i=1; i<argc;) {
        char* opt = argv[i++];
        if (!strcmp(opt, "--duration")) {
            duration = atof(next_arg(argc, argv, i));
        } else if (!strcmp(opt, "--delta")) {
            delta = atof(next_arg(argc, argv, i));
        } else if (!strcmp(opt, "--dirs")) {
            while (i<argc) {
                dirs.push_back(argv[i++]);
            }
        } else {
            help(argv[0]);
        }
    }

    if (duration <= 0) {
        printf("non-pos duration\n");
        exit(1);
    }
    if (delta <= 0) {
        printf("non-pos delta\n");
        exit(1);
    }

    if (dirs.size()) {
        // If we need to do several simulations,
        // use system() to do each one in a separate process,
        // because there are lots of static variables and we need to ensure
        // that they start off with the right initial values
        //
        unsigned int i;
        SIM_RESULTS total_results;
        for (i=0; i<dirs.size(); i++) {
            std::string dir = dirs[i];
            retval = chdir(dir.c_str());
            if (retval) {
                fprintf(stderr, "can't chdir into %s: ", dir.c_str());
                perror("chdir");
                continue;
            }
            char buf[256];
            sprintf(
                buf, "../sim --duration %f --delta %f > %s",
                duration, delta, SUMMARY_FILE
            );
            system(buf);
            FILE* f = fopen(SUMMARY_FILE, "r");
            sim_results.parse(f);
            fclose(f);
            sim_results.print(stdout, dir.c_str());
            total_results.add(sim_results);
            chdir("..");
        }
        total_results.print(stdout, "Total");
    } else {
        read_config_file();
        int retval;
        bool flag;

        retval = gstate.parse_projects(PROJECTS_FILE);
        if (retval) parse_error(PROJECTS_FILE, retval);
        retval = gstate.parse_host(HOST_FILE);
        if (retval) parse_error(HOST_FILE, retval);
        retval = gstate.global_prefs.parse_file(PREFS_FILE, "", flag);
        if (retval) parse_error(PREFS_FILE, retval);

        gstate.set_ncpus();
        gstate.request_work_fetch("init");
        gstate.simulate();

        sim_results.compute();

        // print machine-readable first
        sim_results.print(stdout);

        // then other
        gstate.print_project_results(stdout);
    }
}