from __future__ import absolute_import, division, print_function

import os
import sys
import re
import glob
import fnmatch

import seiscomp.kernel
import seiscomp.config


class Module(seiscomp.kernel.Module):
    def __init__(self, env):
        seiscomp.kernel.Module.__init__(self, env, env.moduleName(__file__))
        self.net = None
        self.sta = None
        self.journalFile = None

    def _readConfig(self):
        cfg = seiscomp.config.Config()
        cfg.readConfig(os.path.join(self.env.SEISCOMP_ROOT,
                                    "etc", "defaults", self.name + ".cfg"))
        cfg.readConfig(os.path.join(
            self.env.SEISCOMP_ROOT, "etc", self.name + ".cfg"))
        try:
            cfg.readConfig(os.path.join(
                os.environ['HOME'], ".seiscomp", self.name + ".cfg"))
        except BaseException:
            pass

        self.journalFile = None
        try:
            if not cfg.getBool("journal.syncWithBindings"):
                sys.stderr.write("! bindings synchronization disabled\n")
                return
        except BaseException:
            sys.stderr.write("! bindings synchronization disabled\n")
            return

        try:
            self.journalFile = cfg.getString("journal.file")
        except BaseException:
            self.journalFile = os.path.join(
                self.env.SEISCOMP_ROOT, "var", "run", self.name + "/journal")

    def _processStation(self, key_dir, profile):
        if profile:
            station_config_file = "profile_%s" % (profile,)
        else:
            station_config_file = "station_%s_%s" % (self.net, self.sta)

        cfg = seiscomp.config.Config()
        cfg.readConfig(os.path.join(key_dir, station_config_file))
        lines = []
        try:
            selectors = cfg.getStrings("selectors")
        except BaseException:
            selectors = ["*.*"]

        for s in selectors:
            lines.append(self.net + "." + self.sta + "." + s)

        return lines

    def requiresKernelModules(self):
        return False

    def supportsAliases(self):
        return True

    def updateConfig(self):
        self._readConfig()

        if not self.journalFile:
            return 0

        rx_binding = re.compile(
            r'(?P<module>[A-Za-z0-9_\.-]+)(:(?P<profile>[A-Za-z0-9_-]+))?$')

        bindings_dir = os.path.join(self.env.SEISCOMP_ROOT, "etc", "key")
        key_dir = os.path.join(bindings_dir, self.name)

        journalEntries = []
        requestedEntries = []
        requestedEntriesSet = set()
        requestedEntriesTree = {}

        try:
            journalFile = open(self.journalFile, "r")
            for l in journalFile:
                journalEntries.append(l.strip().split())
        except BaseException:
            pass
            #raise Exception("Error: unable to create rs2caps request file '%s'" %
            #                self.journalFile)

        files = glob.glob(os.path.join(bindings_dir, "station_*"))

        for f in files:
            try:
                (path, net, sta) = f.split('_')[-3:]
                if not path.endswith("station"):
                    print("invalid path", f)

            except ValueError:
                print("invalid path", f)
                continue

            self.net = net
            self.sta = sta

            if net not in requestedEntriesTree:
                requestedEntriesTree[net] = {}

            if sta not in requestedEntriesTree:
                requestedEntriesTree[net][sta] = []

            fd = open(f)
            line = fd.readline()
            while line:
                line = line.strip()
                if not line or line[0] == '#':
                    line = fd.readline()
                    continue

                m = rx_binding.match(line)
                if not m:
                    print("invalid binding in %s: %s" % (f, line))
                    line = fd.readline()
                    continue

                if m.group('module') != self.name:
                    line = fd.readline()
                    continue

                profile = m.group('profile')
                lines = self._processStation(key_dir, profile)
                if lines:
                    #for l in lines: journalFile.write("%s\n" % l)
                    for l in lines:
                        requestedEntries.append(l)
                        requestedEntriesSet.add(l)
                        requestedEntriesTree[net][sta].append(l)
                    break

            fd.close()

        # Intersect requests with journal
        newJournalEntries = []
        newRequests = []

        oldJournalChannels = set()

        for j in journalEntries:
            oldJournalChannels.add(j[0])
            if (j[0].find('*') >= 0) or (j[0].find('?') >= 0):
                continue

            foundMatch = False
            if j[0] in requestedEntriesSet:
                foundMatch = True
            else:
                n, s, _, _ = j[0].split('.')
                try:
                    for r in requestedEntriesTree[n][s]:
                        if fnmatch.fnmatch(j[0], r):
                            foundMatch = True
                            break
                except BaseException:
                    pass

            if foundMatch:
                newJournalEntries.append(j)
            else:
                sys.stderr.write("- %s\n" % j[0])

        for r in requestedEntries:
            foundMatch = False
            for j in newJournalEntries:
                if r == j[0]:
                    foundMatch = True
                    break

            if not foundMatch:
                newRequests.append(r)
                if r not in oldJournalChannels:
                    sys.stderr.write("+ %s\n" % r)

        try:
            journalFile = open(self.journalFile, "w")
        except BaseException:
            raise Exception(
                "Error: unable to write to rs2caps journal file '%s'" %
                self.journalFile)

        for r in newRequests:
            journalFile.write(r + "\n")
        for j in newJournalEntries:
            journalFile.write(" ".join(j) + "\n")

        return 0