"""
   class for handling .bb files

   Reads a .bb file and obtains its metadata

"""


#  Copyright (C) 2003, 2004  Chris Larson
#  Copyright (C) 2003, 2004  Phil Blundell
#
# SPDX-License-Identifier: GPL-2.0-only
#

import re, bb, os
import bb.build, bb.utils, bb.data_smart

from . import ConfHandler
from .. import resolve_file, ast, logger, ParseError
from .ConfHandler import include, init

__func_start_regexp__    = re.compile(r"(((?P<py>python(?=(\s|\()))|(?P<fr>fakeroot(?=\s)))\s*)*(?P<func>[\w\.\-\+\{\}\$:]+)?\s*\(\s*\)\s*{$" )
__inherit_regexp__       = re.compile(r"inherit\s+(.+)" )
__export_func_regexp__   = re.compile(r"EXPORT_FUNCTIONS\s+(.+)" )
__addtask_regexp__       = re.compile(r"addtask\s+(?P<func>\w+)\s*((before\s*(?P<before>((.*(?=after))|(.*))))|(after\s*(?P<after>((.*(?=before))|(.*)))))*")
__deltask_regexp__       = re.compile(r"deltask\s+(.+)")
__addhandler_regexp__    = re.compile(r"addhandler\s+(.+)" )
__def_regexp__           = re.compile(r"def\s+(\w+).*:" )
__python_func_regexp__   = re.compile(r"(\s+.*)|(^$)|(^#)" )
__python_tab_regexp__    = re.compile(r" *\t")

__infunc__ = []
__inpython__ = False
__body__   = []
__classname__ = ""

cached_statements = {}

def supports(fn, d):
    """Return True if fn has a supported extension"""
    return os.path.splitext(fn)[-1] in [".bb", ".bbclass", ".inc"]

def inherit(files, fn, lineno, d):
    __inherit_cache = d.getVar('__inherit_cache', False) or []
    files = d.expand(files).split()
    for file in files:
        classtype = d.getVar("__bbclasstype", False)
        origfile = file
        for t in ["classes-" + classtype, "classes"]:
            file = origfile
            if not os.path.isabs(file) and not file.endswith(".bbclass"):
                file = os.path.join(t, '%s.bbclass' % file)

            if not os.path.isabs(file):
                bbpath = d.getVar("BBPATH")
                abs_fn, attempts = bb.utils.which(bbpath, file, history=True)
                for af in attempts:
                    if af != abs_fn:
                        bb.parse.mark_dependency(d, af)
                if abs_fn:
                    file = abs_fn

            if os.path.exists(file):
                break

        if not os.path.exists(file):
            raise ParseError("Could not inherit file %s" % (file), fn, lineno)

        if not file in __inherit_cache:
            logger.debug("Inheriting %s (from %s:%d)" % (file, fn, lineno))
            __inherit_cache.append( file )
            d.setVar('__inherit_cache', __inherit_cache)
            try:
                bb.parse.handle(file, d, True)
            except (IOError, OSError) as exc:
                raise ParseError("Could not inherit file %s: %s" % (fn, exc.strerror), fn, lineno)
            __inherit_cache = d.getVar('__inherit_cache', False) or []

def get_statements(filename, absolute_filename, base_name):
    global cached_statements

    try:
        return cached_statements[absolute_filename]
    except KeyError:
        with open(absolute_filename, 'r') as f:
            statements = ast.StatementGroup()

            lineno = 0
            while True:
                lineno = lineno + 1
                s = f.readline()
                if not s: break
                s = s.rstrip()
                feeder(lineno, s, filename, base_name, statements)

        if __inpython__:
            # add a blank line to close out any python definition
            feeder(lineno, "", filename, base_name, statements, eof=True)

        if filename.endswith(".bbclass") or filename.endswith(".inc"):
            cached_statements[absolute_filename] = statements
        return statements

def handle(fn, d, include):
    global __func_start_regexp__, __inherit_regexp__, __export_func_regexp__, __addtask_regexp__, __addhandler_regexp__, __infunc__, __body__, __residue__, __classname__
    __body__ = []
    __infunc__ = []
    __classname__ = ""
    __residue__ = []

    base_name = os.path.basename(fn)
    (root, ext) = os.path.splitext(base_name)
    init(d)

    if ext == ".bbclass":
        __classname__ = root
        __inherit_cache = d.getVar('__inherit_cache', False) or []
        if not fn in __inherit_cache:
            __inherit_cache.append(fn)
            d.setVar('__inherit_cache', __inherit_cache)

    if include != 0:
        oldfile = d.getVar('FILE', False)
    else:
        oldfile = None

    abs_fn = resolve_file(fn, d)

    # actual loading
    statements = get_statements(fn, abs_fn, base_name)

    # DONE WITH PARSING... time to evaluate
    if ext != ".bbclass" and abs_fn != oldfile:
        d.setVar('FILE', abs_fn)

    try:
        statements.eval(d)
    except bb.parse.SkipRecipe:
        d.setVar("__SKIPPED", True)
        if include == 0:
            return { "" : d }

    if __infunc__:
        raise ParseError("Shell function %s is never closed" % __infunc__[0], __infunc__[1], __infunc__[2])
    if __residue__:
        raise ParseError("Leftover unparsed (incomplete?) data %s from %s" % __residue__, fn)

    if ext != ".bbclass" and include == 0:
        return ast.multi_finalize(fn, d)

    if ext != ".bbclass" and oldfile and abs_fn != oldfile:
        d.setVar("FILE", oldfile)

    return d

def feeder(lineno, s, fn, root, statements, eof=False):
    global __func_start_regexp__, __inherit_regexp__, __export_func_regexp__, __addtask_regexp__, __addhandler_regexp__, __def_regexp__, __python_func_regexp__, __inpython__, __infunc__, __body__, bb, __residue__, __classname__

    # Check tabs in python functions:
    # - def py_funcname(): covered by __inpython__
    # - python(): covered by '__anonymous' == __infunc__[0]
    # - python funcname(): covered by __infunc__[3]
    if __inpython__ or (__infunc__ and ('__anonymous' == __infunc__[0] or __infunc__[3])):
        tab = __python_tab_regexp__.match(s)
        if tab:
            bb.warn('python should use 4 spaces indentation, but found tabs in %s, line %s' % (root, lineno))

    if __infunc__:
        if s == '}':
            __body__.append('')
            ast.handleMethod(statements, fn, lineno, __infunc__[0], __body__, __infunc__[3], __infunc__[4])
            __infunc__ = []
            __body__ = []
        else:
            __body__.append(s)
        return

    if __inpython__:
        m = __python_func_regexp__.match(s)
        if m and not eof:
            __body__.append(s)
            return
        else:
            ast.handlePythonMethod(statements, fn, lineno, __inpython__,
                                   root, __body__)
            __body__ = []
            __inpython__ = False

            if eof:
                return

    if s and s[0] == '#':
        if len(__residue__) != 0 and __residue__[0][0] != "#":
            bb.fatal("There is a comment on line %s of file %s:\n'''\n%s\n'''\nwhich is in the middle of a multiline expression. This syntax is invalid, please correct it." % (lineno, fn, s))

    if len(__residue__) != 0 and __residue__[0][0] == "#" and (not s or s[0] != "#"):
        bb.fatal("There is a confusing multiline partially commented expression on line %s of file %s:\n%s\nPlease clarify whether this is all a comment or should be parsed." % (lineno - len(__residue__), fn, "\n".join(__residue__)))

    if s and s[-1] == '\\':
        __residue__.append(s[:-1])
        return

    s = "".join(__residue__) + s
    __residue__ = []

    # Skip empty lines
    if s == '':
        return   

    # Skip comments
    if s[0] == '#':
        return

    m = __func_start_regexp__.match(s)
    if m:
        __infunc__ = [m.group("func") or "__anonymous", fn, lineno, m.group("py") is not None, m.group("fr") is not None]
        return

    m = __def_regexp__.match(s)
    if m:
        __body__.append(s)
        __inpython__ = m.group(1)

        return

    m = __export_func_regexp__.match(s)
    if m:
        ast.handleExportFuncs(statements, fn, lineno, m, __classname__)
        return

    m = __addtask_regexp__.match(s)
    if m:
        if len(m.group().split()) == 2:
            # Check and warn for "addtask task1 task2"
            m2 = re.match(r"addtask\s+(?P<func>\w+)(?P<ignores>.*)", s)
            if m2 and m2.group('ignores'):
                logger.warning('addtask ignored: "%s"' % m2.group('ignores'))

        # Check and warn for "addtask task1 before task2 before task3", the
        # similar to "after"
        taskexpression = s.split()
        for word in ('before', 'after'):
            if taskexpression.count(word) > 1:
                logger.warning("addtask contained multiple '%s' keywords, only one is supported" % word)

        # Check and warn for having task with exprssion as part of task name
        for te in taskexpression:
            if any( ( "%s_" % keyword ) in te for keyword in bb.data_smart.__setvar_keyword__ ):
                raise ParseError("Task name '%s' contains a keyword which is not recommended/supported.\nPlease rename the task not to include the keyword.\n%s" % (te, ("\n".join(map(str, bb.data_smart.__setvar_keyword__)))), fn)
        ast.handleAddTask(statements, fn, lineno, m)
        return

    m = __deltask_regexp__.match(s)
    if m:
        ast.handleDelTask(statements, fn, lineno, m)
        return

    m = __addhandler_regexp__.match(s)
    if m:
        ast.handleBBHandlers(statements, fn, lineno, m)
        return

    m = __inherit_regexp__.match(s)
    if m:
        ast.handleInherit(statements, fn, lineno, m)
        return

    return ConfHandler.feeder(lineno, s, fn, statements)

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