#!/usr/bin/env python
# ex:ts=4:sw=4:sts=4:et
# -*- tab-width: 4; c-basic-offset: 4; indent-tabs-mode: nil -*-
"""class for handling configuration data files

   Reads the file and obtains its metadata"""

import re, oe.data, os, sys
from oe import debug, fatal

#__config_regexp__  = re.compile( r"(?P<exp>export\s*)?(?P<var>[a-zA-Z0-9\-_+.${}]+)\s*(?P<colon>:)?(?P<ques>\?)?=\s*(?P<apo>['\"]?)(?P<value>.*)(?P=apo)$")
__config_regexp__  = re.compile( r"(?P<exp>export\s*)?(?P<var>[a-zA-Z0-9\-_+.${}/]+)(\[(?P<flag>[a-zA-Z0-9\-_+.]+)\])?\s*((?P<colon>:=)|(?P<ques>\?=)|(?P<append>\+=)|(?P<prepend>=\+)|=)\s*(?P<apo>['\"]?)(?P<value>.*)(?P=apo)$")
__include_regexp__ = re.compile( r"include\s+(.+)" )

def init(data):
    if not oe.data.getVar('TOPDIR', data):
        oe.data.setVar('TOPDIR', os.getcwd(), data)
    if not oe.data.getVar('OEPATH', data):
        oebuild = os.path.abspath(sys.argv[0])
        oebin = os.path.dirname(oebuild)
        oedir = os.path.dirname(oebin)
        oe.data.setVar('OEPATH', "${TOPDIR}:%s:%s:${HOME}/.oe:${OEDIR}/bin:${OEDIR}:%s/share/oe" % (oebin, oedir, sys.prefix), data)

def supports(fn, d):
    return localpath(fn, d)[-5:] == ".conf"

def localpath(fn, d):
    if os.path.exists(fn):
        return fn

    localfn = None
    try:
        localfn = oe.fetch.localpath(fn, d)
    except oe.MalformedUrl:
        pass

    if not localfn:
        localfn = fn
    return localfn

def obtain(fn, data = {}):
    import sys, oe
    fn = oe.data.expand(fn, data)
    localfn = oe.data.expand(localpath(fn, data), data)

    if localfn != fn:
        dldir = oe.data.getVar('DL_DIR', data, 1)
        if not dldir:
            debug(1, "obtain: DL_DIR not defined")
            return localfn
        oe.mkdirhier(dldir)
        try:
            oe.fetch.init([fn])
        except oe.fetch.NoMethodError:
            (type, value, traceback) = sys.exc_info()
            debug(1, "obtain: no method: %s" % value)
            return localfn

        try:
            oe.fetch.go(data)
        except oe.fetch.MissingParameterError:
            (type, value, traceback) = sys.exc_info()
            debug(1, "obtain: missing parameters: %s" % value)
            return localfn
        except oe.fetch.FetchError:
            (type, value, traceback) = sys.exc_info()
            debug(1, "obtain: failed: %s" % value)
            return localfn
    return localfn


def include(oldfn, fn, data = {}):
    if oldfn == fn: # prevent infinate recursion
        return None

    import oe
    fn = oe.data.expand(fn, data)
    oldfn = oe.data.expand(oldfn, data)

    from oe.parse import handle
    try:
        ret = handle(fn, data, 1)
    except IOError:
        debug(2, "CONF file '%s' not found" % fn)

def handle(fn, data = {}, include = 0):
    if include:
        inc_string = "including"
    else:
        inc_string = "reading"
    init(data)

    if include == 0:
        oe.data.inheritFromOS(data)
        oldfile = None
    else:
        oldfile = oe.data.getVar('FILE', data)

    fn = obtain(fn, data)
    oepath = ['.']
    if not os.path.isabs(fn):
        f = None
        voepath = oe.data.getVar("OEPATH", data)
        if voepath:
            oepath += voepath.split(":")
        for p in oepath:
            currname = os.path.join(oe.data.expand(p, data), fn)
            if os.access(currname, os.R_OK):
                f = open(currname, 'r')
                abs_fn = currname
                debug(1, "CONF %s %s" % (inc_string, currname))
                break
        if f is None:
            raise IOError("file not found")
    else:
        f = open(fn,'r')
        debug(1, "CONF %s %s" % (inc_string,fn))
        abs_fn = fn

    if include:
        oe.parse.mark_dependency(data, abs_fn)

    lineno = 0
    oe.data.setVar('FILE', fn, data)
    while 1:
        lineno = lineno + 1
        s = f.readline()
        if not s: break
        w = s.strip()
        if not w: continue          # skip empty lines
        s = s.rstrip()
        if s[0] == '#': continue    # skip comments
        while s[-1] == '\\':
            s2 = f.readline()[:-1].strip()
            lineno = lineno + 1
            s = s[:-1] + s2
        feeder(lineno, s, fn, data)

    if oldfile:
        oe.data.setVar('FILE', oldfile, data)

    if oe.data.getVar('OEDIR', data, 1):
        oe.note("OEDIR is deprecated, please switch to OEPATH.")
    return data

def feeder(lineno, s, fn, data = {}):
    m = __config_regexp__.match(s)
    if m:
        groupd = m.groupdict()
        key = groupd["var"]
        if "exp" in groupd and groupd["exp"] != None:
            oe.data.setVarFlag(key, "export", 1, data)
        if "ques" in groupd and groupd["ques"] != None:
            val = oe.data.getVar(key, data)
            if val == None:
                val = groupd["value"]
        elif "colon" in groupd and groupd["colon"] != None:
            val = oe.data.expand(groupd["value"], data)
        elif "append" in groupd and groupd["append"] != None:
            val = "%s %s" % ((oe.data.getVar(key, data) or ""), groupd["value"])
        elif "prepend" in groupd and groupd["prepend"] != None:
            val = "%s %s" % (groupd["value"], (oe.data.getVar(key, data) or ""))
        else:
            val = groupd["value"]
        if 'flag' in groupd and groupd['flag'] != None:
#           oe.note("setVarFlag(%s, %s, %s, data)" % (key, groupd['flag'], val))
            oe.data.setVarFlag(key, groupd['flag'], val, data)
        else:
            oe.data.setVar(key, val, data)
        return

    m = __include_regexp__.match(s)
    if m:
        s = oe.data.expand(m.group(1), data)
#       debug(2, "CONF %s:%d: including %s" % (fn, lineno, s))
        include(fn, s, data)
        return

    raise ParseError("%s:%d: unparsed line: '%s'" % (fn, lineno, s));

# Add us to the handlers list
from oe.parse import handlers
handlers.append({'supports': supports, 'handle': handle, 'init': init})
del handlers