# encoding: UTF-8
# api: python
# type: handler
# category: io
# title: Plugin configuration
# description: Read meta data, pyz/package contents, module locating
# version: 0.6.8
# priority: core
# docs: http://fossil.include-once.org/streamtuner2/wiki/plugin+meta+data
# config: -
#
# Provides plugin lookup and meta data extraction utility functions.
# It's used to abstract module+option management in applications.
# For consolidating internal use and external/tool accessibility.

import sys
import os
import re
import pkgutil
import inspect
from compat2and3 import find_executable
try:
    from compat2and3 import gzip_decode
except:
    from gzip import decompress as gzip_decode  # Py3 only
import zipfile
import argparse

        for name in core:
            self.have[name] = plugin_meta(module=name, extra_base=["config"])
        # aliases
        for name, meta in self.have.items():
            if meta.get("alias"):
                for alias in re.split("\s*[,;]\s*", meta["alias"]):
                    self.have[alias] = self.have[name]














    # basic plugin pre-screening (skip __init__, filter by api:,
    # exclude installed & same-version plugins)
    def valid(self, newpl):
        id = newpl.get("$name", "__invalid")
        have_ver = self.have.get(id, {}).get("version", "0")
        if id.find("__") == 0:
            pass
        elif newpl.get("api") not in ("python", "streamtuner2"):
            pass
        elif set((newpl.get("status"), newpl.get("priority"))).intersection(set(("obsolete", "broken"))):
            pass
        elif have_ver >= newpl.get("version", "0.0"):
            pass
        else:
            return True

    # Verify depends: and breaks: against existing plugins/modules
    def depends(self, plugin):
        r = True
        if plugin.get("depends"):
            r &= self.and_or(self.split(plugin["depends"]), self.have)
        if plugin.get("breaks"):
            r &= self.neither(self.split(plugin["breaks"]), self.have)
        return r

    # Split trivial "pkg | alt, mod >= 1, uikit < 4.0" string into nested list [[dep],[alt,alt],[dep]]
    def split(self, dep_str):
        dep_cmp = []
        for alt_str in re.split(r"\s*[,;]+\s*", dep_str):
            alt_cmp = []
            # split alternatives |
            for part in re.split(r"\s*\|+\s*", alt_str):
                # skip deb:pkg-name, rpm:name, bin:name etc.
                if not len(part):
                    continue
                if part.find(":") >= 0:
                    self.have[part] = { "version": self.module_test(*part.split(":")) }
                # find comparison and version num
                part += " >= 0"
                m = re.search(r"([\w.:-]+)\s*\(?\s*([>=<!~]+)\s*([\d.]+([-~.]\w+)*)", part)
                if m and m.group(2):
                    alt_cmp.append([m.group(i) for i in (1, 2, 3)])
            if alt_cmp:
                dep_cmp.append(alt_cmp)
        return dep_cmp

    # Single comparison
    def cmp(self, d, have, absent=True):

        name, op, ver = d

        # absent=True is the relaxed check, will ignore unknown plugins // set absent=False or None for strict check (as in breaks: rule e.g.)
        if not have.get(name, {}).get("version"):
            return absent
        # curr = installed version
        curr = have[name]["version"]
        tbl = {
            ">=": curr >= ver,
            "<=": curr <= ver,
            "==": curr == ver,
            ">":  curr > ver,
            "<":  curr < ver,
            "!=": curr != ver,
        }
        r = tbl.get(op, True)
        #print "log.VERSION_COMPARE: ", name, " → (", curr, op, ver, ") == ", r
        return r

    # Compare nested structure of [[dep],[alt,alt]]
    def and_or(self, deps, have, r = True):
        #print deps
        return not False in [True in [self.cmp(d, have) for d in alternatives] for alternatives in deps]

    # Breaks/Conflicts: check [[or],[or]]
    def neither(self, deps, have):
        return not True in [self.cmp(d, have, absent=None) for cnd in deps for d in cnd]

    # Resolves/injects complex "bin:name" or "python:name" dependency URNs
    def module_test(self, type, name):
        return "1"  # disabled for now
        if "_" + type in dir(self):
            return "1" if bool(getattr(self, "_" + type)(name)) else "-1"
    # `bin:name` lookup
    def _bin(self, name):
        return find_executable(name)
    # `python:module` test
    def _python(self, name):
        return __import__("imp").find_module(name) is not None


# Add plugin defaults to conf.* store
# ‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾
# Utility function which applies plugin meta data to a config
# store. Which in the case of streamtuner2 is really just a
# dictionary `conf{}` and a plugin list in `conf.plugins{}`.
#