#!/usr/bin/env pmpython
#
# Copyright (C) 2015-2021 Marko Myllynen <myllynen@redhat.com>
#
# This program is free software; you can redistribute it and/or modify it
# under the terms of the GNU General Public License as published by the
# Free Software Foundation; either version 2 of the License, or (at your
# option) any later version.
#
# This program 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 General Public License
# for more details.

# pylint: disable=superfluous-parens
# pylint: disable=invalid-name, line-too-long, no-self-use
# pylint: disable=too-many-boolean-expressions, too-many-statements
# pylint: disable=too-many-instance-attributes, too-many-locals
# pylint: disable=too-many-branches, too-many-nested-blocks
# pylint: disable=broad-except

""" PCP to XXX Bridge """

# Common imports
from collections import OrderedDict
import errno
import time
import sys

# Our imports
import os

# PCP Python PMAPI
from pcp import pmapi, pmconfig
from cpmapi import PM_CONTEXT_ARCHIVE, PM_IN_NULL, PM_DEBUG_APPL1, PM_TIME_SEC

# Default config
DEFAULT_CONFIG = ["./pcp2XXX.conf", "$HOME/.pcp2XXX.conf", "$HOME/.pcp/pcp2XXX.conf", "$PCP_SYSCONF_DIR/pcp2XXX.conf"]

# Defaults
CONFVER = 1
TIMEFMT = "%Y-%m-%d %H:%M:%S"

class PCP2XXX(object):
    """ PCP to XXX """
    def __init__(self):
        """ Construct object, prepare for command line handling """
        self.context = None
        self.daemonize = 0
        self.pmconfig = pmconfig.pmConfig(self)
        self.opts = self.options()

        # Configuration directives
        self.keys = ('source', 'output', 'derived', 'header', 'globals',
                     'samples', 'interval', 'type', 'precision', 'daemonize',
                     'timefmt', # XXX Custom options here, if any (see below)
                     'count_scale', 'space_scale', 'time_scale', 'version',
                     'count_scale_force', 'space_scale_force', 'time_scale_force',
                     'type_prefer', 'precision_force', 'limit_filter', 'limit_filter_force',
                     'live_filter', 'rank', 'invert_filter', 'predicate', 'names_change',
                     'speclocal', 'instances', 'ignore_incompat', 'ignore_unknown',
                     'omit_flat')

        # Ignored for pmrep(1) compatibility
        # XXX Keep in sync with self.keys in pmrep
        self.keys_ignore = (
                     'timestamp', 'unitinfo', 'colxrow', 'separate_header', 'fixed_header',
                     'delay', 'width', 'delimiter', 'extcsv', 'width_force',
                     'extheader', 'repeat_header', 'interpol',
                     'dynamic_header', 'overall_rank', 'overall_rank_alt', 'sort_metric',
                     'instinfo', 'include_labels', 'include_texts')

        # The order of preference for options (as present):
        # 1 - command line options
        # 2 - options from configuration file(s)
        # 3 - built-in defaults defined below
        self.check = 0
        self.version = CONFVER
        self.source = "local:"
        self.output = None # For pmrep conf file compat only
        self.speclocal = None
        self.derived = None
        self.header = 1
        self.globals = 1
        self.samples = None # forever
        # XXX Adjust default interval as needed
        self.interval = pmapi.timeval(10)      # 10 sec
        self.opts.pmSetOptionInterval(str(10)) # 10 sec
        self.delay = 0
        self.type = 0
        self.type_prefer = self.type
        self.ignore_incompat = 0
        self.ignore_unknown = 0
        self.names_change = 0 # ignore
        self.instances = []
        self.live_filter = 0
        self.rank = 0
        self.limit_filter = 0
        self.limit_filter_force = 0
        self.invert_filter = 0
        self.predicate = None
        self.omit_flat = 0
        self.precision = 3 # .3f
        self.precision_force = None
        self.timefmt = TIMEFMT
        self.interpol = 0
        self.count_scale = None
        self.count_scale_force = None
        self.space_scale = None
        self.space_scale_force = None
        self.time_scale = None
        self.time_scale_force = None

        # Not in pcp2XXX.conf, won't overwrite
        self.outfile = None

        # XXX Custom options here, if any (keep in sync with self.keys)

        # Internal
        self.runtime = -1

        self.writer = None

        # Performance metrics store
        # key - metric name
        # values - 0:txt label, 1:instance(s), 2:unit/scale, 3:type,
        #          4:width, 5:pmfg item, 6:precision, 7:limit
        self.metrics = OrderedDict()
        self.pmfg = None
        self.pmfg_ts = None

        # Read configuration and prepare to connect
        self.config = self.pmconfig.set_config_path(DEFAULT_CONFIG)
        self.pmconfig.read_options()
        self.pmconfig.read_cmd_line()
        self.pmconfig.prepare_metrics()
        self.pmconfig.set_signal_handler()

    def options(self):
        """ Setup default command line argument option handling """
        opts = pmapi.pmOptions()
        opts.pmSetOptionCallback(self.option)
        opts.pmSetOverrideCallback(self.option_override)
        # XXX Append custom options, if any (keep in sync with self.keys)
        opts.pmSetShortOptions("a:h:LK:c:Ce:D:V?HGA:S:T:O:s:t:rRIi:jJ:4:58:9:nN:vP:0:q:b:y:Q:B:Y:F:f:Z:z")
        opts.pmSetShortUsage("[option...] metricspec [...]")

        opts.pmSetLongOptionHeader("General options")
        opts.pmSetLongOptionArchive()      # -a/--archive
        opts.pmSetLongOptionArchiveFolio() # --archive-folio
        opts.pmSetLongOptionContainer()    # --container
        opts.pmSetLongOptionHost()         # -h/--host
        opts.pmSetLongOptionLocalPMDA()    # -L/--local-PMDA
        opts.pmSetLongOptionSpecLocal()    # -K/--spec-local
        opts.pmSetLongOption("config", 1, "c", "FILE", "config file path")
        opts.pmSetLongOption("check", 0, "C", "", "check config and metrics and exit")
        opts.pmSetLongOption("output-file", 1, "F", "OUTFILE", "output file")
        opts.pmSetLongOption("derived", 1, "e", "FILE|DFNT", "derived metrics definitions")
        opts.pmSetLongOption("daemonize", 0, "", "", "daemonize on startup")
        opts.pmSetLongOptionDebug()        # -D/--debug
        opts.pmSetLongOptionVersion()      # -V/--version
        opts.pmSetLongOptionHelp()         # -?/--help

        opts.pmSetLongOptionHeader("Reporting options")
        opts.pmSetLongOption("no-header", 0, "H", "", "omit headers")
        opts.pmSetLongOption("no-globals", 0, "G", "", "omit global metrics")
        opts.pmSetLongOptionAlign()        # -A/--align
        opts.pmSetLongOptionStart()        # -S/--start
        opts.pmSetLongOptionFinish()       # -T/--finish
        opts.pmSetLongOptionOrigin()       # -O/--origin
        opts.pmSetLongOptionSamples()      # -s/--samples
        opts.pmSetLongOptionInterval()     # -t/--interval
        opts.pmSetLongOptionTimeZone()     # -Z/--timezone
        opts.pmSetLongOptionHostZone()     # -z/--hostzone
        opts.pmSetLongOption("raw", 0, "r", "", "output raw counter values (no rate conversion)")
        opts.pmSetLongOption("raw-prefer", 0, "R", "", "prefer output raw counter values (no rate conversion)")
        opts.pmSetLongOption("ignore-incompat", 0, "I", "", "ignore incompatible instances (default: abort)")
        opts.pmSetLongOption("ignore-unknown", 0, "5", "", "ignore unknown metrics (default: abort)")
        opts.pmSetLongOption("names-change", 1, "4", "ACTION", "update/ignore/abort on PMNS change (default: ignore)")
        opts.pmSetLongOption("instances", 1, "i", "STR", "instances to report (default: all current)")
        opts.pmSetLongOption("live-filter", 0, "j", "", "perform instance live filtering")
        opts.pmSetLongOption("rank", 1, "J", "COUNT", "limit results to COUNT highest/lowest valued instances")
        opts.pmSetLongOption("limit-filter", 1, "8", "LIMIT", "default limit for value filtering")
        opts.pmSetLongOption("limit-filter-force", 1, "9", "LIMIT", "forced limit for value filtering")
        opts.pmSetLongOption("invert-filter", 0, "n", "", "perform ranking before live filtering")
        opts.pmSetLongOption("predicate", 1, "N", "METRIC", "set predicate filter reference metric")
        opts.pmSetLongOption("omit-flat", 0, "v", "", "omit single-valued metrics")
        opts.pmSetLongOption("precision", 1, "P", "N", "prefer N digits after decimal separator (default: 3)")
        opts.pmSetLongOption("precision-force", 1, "0", "N", "force N digits after decimal separator")
        opts.pmSetLongOption("timestamp-format", 1, "f", "STR", "strftime string for timestamp format")
        opts.pmSetLongOption("count-scale", 1, "q", "SCALE", "default count unit")
        opts.pmSetLongOption("count-scale-force", 1, "Q", "SCALE", "forced count unit")
        opts.pmSetLongOption("space-scale", 1, "b", "SCALE", "default space unit")
        opts.pmSetLongOption("space-scale-force", 1, "B", "SCALE", "forced space unit")
        opts.pmSetLongOption("time-scale", 1, "y", "SCALE", "default time unit")
        opts.pmSetLongOption("time-scale-force", 1, "Y", "SCALE", "forced time unit")

        # XXX Custom options here, if any (keep in sync with self.keys)

        return opts

    def option_override(self, opt):
        """ Override standard PCP options """
        if opt in ('g', 'H', 'K', 'n', 'N', 'p'):
            return 1
        return 0

    def option(self, opt, optarg, _index):
        """ Perform setup for individual command line option """
        if opt == 'daemonize':
            self.daemonize = 1
        elif opt == 'K':
            if not self.speclocal or not self.speclocal.startswith(";"):
                self.speclocal = ";" + optarg
            else:
                self.speclocal = self.speclocal + ";" + optarg
        elif opt == 'c':
            self.config = optarg
        elif opt == 'C':
            self.check = 1
        elif opt == 'F':
            if os.path.exists(optarg):
                sys.stderr.write("File %s already exists.\n" % optarg)
                sys.exit(1)
            self.outfile = optarg
        elif opt == 'e':
            if not self.derived or not self.derived.startswith(";"):
                self.derived = ";" + optarg
            else:
                self.derived = self.derived + ";" + optarg
        elif opt == 'H':
            self.header = 0
        elif opt == 'G':
            self.globals = 0
        elif opt == 'r':
            self.type = 1
        elif opt == 'R':
            self.type_prefer = 1
        elif opt == 'I':
            self.ignore_incompat = 1
        elif opt == '5':
            self.ignore_unknown = 1
        elif opt == '4':
            if optarg == 'ignore':
                self.names_change = 0
            elif optarg == 'abort':
                self.names_change = 1
            elif optarg == 'update':
                self.names_change = 2
            else:
                sys.stderr.write("Unknown names-change action '%s' specified.\n" % optarg)
                sys.exit(1)
        elif opt == 'i':
            self.instances = self.instances + self.pmconfig.parse_instances(optarg)
        elif opt == 'j':
            self.live_filter = 1
        elif opt == 'J':
            self.rank = optarg
        elif opt == '8':
            self.limit_filter = optarg
        elif opt == '9':
            self.limit_filter_force = optarg
        elif opt == 'n':
            self.invert_filter = 1
        elif opt == 'N':
            self.predicate = optarg
        elif opt == 'v':
            self.omit_flat = 1
        elif opt == 'P':
            self.precision = optarg
        elif opt == '0':
            self.precision_force = optarg
        elif opt == 'f':
            self.timefmt = optarg
        elif opt == 'q':
            self.count_scale = optarg
        elif opt == 'Q':
            self.count_scale_force = optarg
        elif opt == 'b':
            self.space_scale = optarg
        elif opt == 'B':
            self.space_scale_force = optarg
        elif opt == 'y':
            self.time_scale = optarg
        elif opt == 'Y':
            self.time_scale_force = optarg
        # XXX Custom options here, if any (keep in sync with self.keys)
        else:
            raise pmapi.pmUsageErr()

    def connect(self):
        """ Establish PMAPI context """
        context, self.source = pmapi.pmContext.set_connect_options(self.opts, self.source, self.speclocal)

        self.pmfg = pmapi.fetchgroup(context, self.source)
        self.pmfg_ts = self.pmfg.extend_timestamp()
        self.context = self.pmfg.get_context()

        if pmapi.c_api.pmSetContextOptions(self.context.ctx, self.opts.mode, self.opts.delta):
            raise pmapi.pmUsageErr()

    def validate_config(self):
        """ Validate configuration options """
        if self.version != CONFVER:
            sys.stderr.write("Incompatible configuration file version (read v%s, need v%d).\n" % (self.version, CONFVER))
            sys.exit(1)

        self.pmconfig.validate_common_options()

        # XXX Custom options handling here, if needed

        self.pmconfig.validate_metrics(curr_insts=not self.live_filter)
        self.pmconfig.finalize_options()

    def execute(self):
        """ Fetch and report """
        # Debug
        if self.context.pmDebug(PM_DEBUG_APPL1):
            sys.stdout.write("Known config file keywords: " + str(self.keys) + "\n")
            sys.stdout.write("Known metric spec keywords: " + str(self.pmconfig.metricspec) + "\n")

        # Set delay mode, interpolation
        if self.context.type != PM_CONTEXT_ARCHIVE:
            self.delay = 1
            self.interpol = 1

        # Common preparations
        self.context.prepare_execute(self.opts, False, self.interpol, self.interval)

        # Headers
        if self.header == 1:
            self.header = 0
            self.write_header()

        # Just checking
        if self.check == 1:
            return

        # Daemonize when requested
        if self.daemonize == 1:
            self.opts.daemonize()

        # Align poll interval to host clock
        if self.context.type != PM_CONTEXT_ARCHIVE and self.opts.pmGetOptionAlignment():
            align = float(self.opts.pmGetOptionAlignment()) - (time.time() % float(self.opts.pmGetOptionAlignment()))
            time.sleep(align)

        # Main loop
        refresh_metrics = 0
        while self.samples != 0:
            # Refresh metrics as needed
            if refresh_metrics:
                refresh_metrics = 0
                self.pmconfig.update_metrics(curr_insts=not self.live_filter)

            # Fetch values
            refresh_metrics = self.pmconfig.fetch()
            if refresh_metrics < 0:
                break

            # Report and prepare for the next round
            self.report(self.pmfg_ts())
            if self.samples and self.samples > 0:
                self.samples -= 1
            if self.delay and self.interpol and self.samples != 0:
                self.pmconfig.pause()

        # Allow to flush buffered values / say goodbye
        self.report(None)

    def report(self, tstamp):
        """ Report metric values """
        if tstamp is not None:
            tstamp = tstamp.strftime(self.timefmt)

        self.write_XXX(tstamp)

    def write_header(self):
        """ Write info header """
        #output = self.outfile if self.outfile else "stdout"

        if not self.outfile:
            self.header = 1
            # XXX Common header here if needed
            #sys.stdout.write(XXX)

        if self.context.type == PM_CONTEXT_ARCHIVE:
            # XXX Reading from archive header here if wanted
            #sys.stdout.write(XXX "Writing %d archived metrics to %s...\n(Ctrl-C to stop)\n" % (len(self.metrics), output))
            return

        # XXX Header when reading live metrics here if needed
        #sys.stdout.write(XXX "Writing %d metrics to %s" % (len(self.metrics), output))
        #if self.runtime != -1:
        #    sys.stdout.write(":\n%s samples(s) with %.1f sec interval ~ %d sec runtime.\n" % (self.samples, float(self.interval), self.runtime))
        #elif self.samples:
        #    duration = (self.samples - 1) * float(self.interval)
        #    sys.stdout.write(":\n%s samples(s) with %.1f sec interval ~ %d sec runtime.\n" % (self.samples, float(self.interval), duration))
        #else:
        #    sys.stdout.write("...\n(Ctrl-C to stop)\n")

    def write_XXX(self, timestamp):
        """ Write results in XXX format """
        if timestamp is None:
            # Silent goodbye, close in finalize()
            return

        ts = self.context.datetime_to_secs(self.pmfg_ts(), PM_TIME_SEC)

        if not self.writer:
            if self.outfile is None:
                self.writer = sys.stdout
            else:
                self.writer = open(self.outfile, 'wt')
            # XXX Write some first round details here if needed
            #host = self.context.pmGetContextHostName()
            #timez = self.context.posix_tz_to_utc_offset(self.context.get_current_tz(self.opts))

        # XXX Only retrieve non-valid results if needed
        results = self.pmconfig.get_ranked_results(valid_only=True)

        for metric in results:
            i = list(self.metrics.keys()).index(metric)
            # XXX Do the real work here
            print("Metric %s details (last fetch: %d):" % (metric, ts))
            print("\tid: %s\ttype: %d" % (self.pmconfig.pmids[i], self.pmconfig.descs[i].contents.type))
            print("\tsem: %s\t\tindom: %d" % (self.pmconfig.descs[i].contents.sem, self.pmconfig.descs[i].contents.indom))
            fmt = "." + str(self.metrics[metric][6]) + "f"
            for inst, name, value in results[metric]:
                value = format(value, fmt) if isinstance(value, float) else str(value)
                # XXX Do the real work here
                if inst == PM_IN_NULL:
                    print("metric '%s' has value '%s'!" % (metric, value))
                else:
                    print("metric '%s' instance '%s' has value '%s'!" % (metric, name, value))

    def finalize(self):
        """ Finalize and clean up """
        if self.writer:
            try:
                #self.writer.write(XXX)
                self.writer.flush()
            except IOError as error:
                if error.errno != errno.EPIPE:
                    raise
            try:
                self.writer.close()
            except Exception:
                pass
            self.writer = None

if __name__ == '__main__':
    try:
        P = PCP2XXX()
        P.connect()
        P.validate_config()
        P.execute()
        P.finalize()
    except pmapi.pmErr as error:
        sys.stderr.write("%s: %s" % (error.progname(), error.message()))
        if error.message() == "Connection refused":
            sys.stderr.write("; is pmcd running?")
        sys.stderr.write("\n")
        sys.exit(1)
    except pmapi.pmUsageErr as usage:
        usage.message()
        sys.exit(1)
    except IOError as error:
        if error.errno != errno.EPIPE:
            sys.stderr.write("%s\n" % str(error))
            sys.exit(1)
    except KeyboardInterrupt:
        sys.stdout.write("\n")
        P.finalize()
