#!/usr/bin/env python3
# Copyright 2016 The Meson development team

# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at

#     http://www.apache.org/licenses/LICENSE-2.0

# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

# This class contains the basic functionality needed to run any interpreter
# or an interpreter-based tool.

# This tool is used to manipulate an existing Meson build definition.
#
# - add a file to a target
# - remove files from a target
# - move targets
# - reindent?

from .ast import IntrospectionInterpreter, build_target_functions, AstConditionLevel, AstIDGenerator, AstIndentationGenerator, AstPrinter
from mesonbuild.mesonlib import MesonException
from . import mlog, environment
from functools import wraps
from typing import List, Dict, Optional
from .mparser import Token, ArrayNode, ArgumentNode, AssignmentNode, BaseNode, BooleanNode, ElementaryNode, IdNode, FunctionNode, StringNode
import json, os, re, sys

class RewriterException(MesonException):
    pass

def add_arguments(parser, formatter=None):
    parser.add_argument('-s', '--sourcedir', type=str, default='.', metavar='SRCDIR', help='Path to source directory.')
    parser.add_argument('-V', '--verbose', action='store_true', default=False, help='Enable verbose output')
    parser.add_argument('-S', '--skip-errors', dest='skip', action='store_true', default=False, help='Skip errors instead of aborting')
    subparsers = parser.add_subparsers(dest='type', title='Rewriter commands', description='Rewrite command to execute')

    # Target
    tgt_parser = subparsers.add_parser('target', help='Modify a target', formatter_class=formatter)
    tgt_parser.add_argument('-s', '--subdir', default='', dest='subdir', help='Subdirectory of the new target (only for the "add_target" action)')
    tgt_parser.add_argument('--type', dest='tgt_type', choices=rewriter_keys['target']['target_type'][2], default='executable',
                            help='Type of the target to add (only for the "add_target" action)')
    tgt_parser.add_argument('target', help='Name or ID of the target')
    tgt_parser.add_argument('operation', choices=['add', 'rm', 'add_target', 'rm_target', 'info'],
                            help='Action to execute')
    tgt_parser.add_argument('sources', nargs='*', help='Sources to add/remove')

    # KWARGS
    kw_parser = subparsers.add_parser('kwargs', help='Modify keyword arguments', formatter_class=formatter)
    kw_parser.add_argument('operation', choices=rewriter_keys['kwargs']['operation'][2],
                           help='Action to execute')
    kw_parser.add_argument('function', choices=list(rewriter_func_kwargs.keys()),
                           help='Function type to modify')
    kw_parser.add_argument('id', help='ID of the function to modify (can be anything for "project")')
    kw_parser.add_argument('kwargs', nargs='*', help='Pairs of keyword and value')

    # Default options
    def_parser = subparsers.add_parser('default-options', help='Modify the project default options', formatter_class=formatter)
    def_parser.add_argument('operation', choices=rewriter_keys['default_options']['operation'][2],
                            help='Action to execute')
    def_parser.add_argument('options', nargs='*', help='Key, value pairs of configuration option')

    # JSON file/command
    cmd_parser = subparsers.add_parser('command', help='Execute a JSON array of commands', formatter_class=formatter)
    cmd_parser.add_argument('json', help='JSON string or file to execute')

class RequiredKeys:
    def __init__(self, keys):
        self.keys = keys

    def __call__(self, f):
        @wraps(f)
        def wrapped(*wrapped_args, **wrapped_kwargs):
            assert(len(wrapped_args) >= 2)
            cmd = wrapped_args[1]
            for key, val in self.keys.items():
                typ = val[0] # The type of the value
                default = val[1] # The default value -- None is required
                choices = val[2] # Valid choices -- None is for everything
                if key not in cmd:
                    if default is not None:
                        cmd[key] = default
                    else:
                        raise RewriterException('Key "{}" is missing in object for {}'
                                                .format(key, f.__name__))
                if not isinstance(cmd[key], typ):
                    raise RewriterException('Invalid type of "{}". Required is {} but provided was {}'
                                            .format(key, typ.__name__, type(cmd[key]).__name__))
                if choices is not None:
                    assert(isinstance(choices, list))
                    if cmd[key] not in choices:
                        raise RewriterException('Invalid value of "{}": Possible values are {} but provided was "{}"'
                                                .format(key, choices, cmd[key]))
            return f(*wrapped_args, **wrapped_kwargs)

        return wrapped

class MTypeBase:
    def __init__(self, node: Optional[BaseNode] = None):
        if node is None:
            self.node = self._new_node()  # lgtm [py/init-calls-subclass] (node creation does not depend on base class state)
        else:
            self.node = node
        self.node_type = None
        for i in self.supported_nodes():  # lgtm [py/init-calls-subclass] (listing nodes does not depend on base class state)
            if isinstance(self.node, i):
                self.node_type = i

    def _new_node(self):
        # Overwrite in derived class
        return BaseNode()

    def can_modify(self):
        return self.node_type is not None

    def get_node(self):
        return self.node

    def supported_nodes(self):
        # Overwrite in derived class
        return []

    def set_value(self, value):
        # Overwrite in derived class
        mlog.warning('Cannot set the value of type', mlog.bold(type(self).__name__), '--> skipping')

    def add_value(self, value):
        # Overwrite in derived class
        mlog.warning('Cannot add a value of type', mlog.bold(type(self).__name__), '--> skipping')

    def remove_value(self, value):
        # Overwrite in derived class
        mlog.warning('Cannot remove a value of type', mlog.bold(type(self).__name__), '--> skipping')

    def remove_regex(self, value):
        # Overwrite in derived class
        mlog.warning('Cannot remove a regex in type', mlog.bold(type(self).__name__), '--> skipping')

class MTypeStr(MTypeBase):
    def __init__(self, node: Optional[BaseNode] = None):
        super().__init__(node)

    def _new_node(self):
        return StringNode(Token('', '', 0, 0, 0, None, ''))

    def supported_nodes(self):
        return [StringNode]

    def set_value(self, value):
        self.node.value = str(value)

class MTypeBool(MTypeBase):
    def __init__(self, node: Optional[BaseNode] = None):
        super().__init__(node)

    def _new_node(self):
        return StringNode(Token('', '', 0, 0, 0, None, False))

    def supported_nodes(self):
        return [BooleanNode]

    def set_value(self, value):
        self.node.value = bool(value)

class MTypeID(MTypeBase):
    def __init__(self, node: Optional[BaseNode] = None):
        super().__init__(node)

    def _new_node(self):
        return StringNode(Token('', '', 0, 0, 0, None, ''))

    def supported_nodes(self):
        return [IdNode]

    def set_value(self, value):
        self.node.value = str(value)

class MTypeList(MTypeBase):
    def __init__(self, node: Optional[BaseNode] = None):
        super().__init__(node)

    def _new_node(self):
        return ArrayNode(ArgumentNode(Token('', '', 0, 0, 0, None, '')), 0, 0, 0, 0)

    def _new_element_node(self, value):
        # Overwrite in derived class
        return BaseNode()

    def _ensure_array_node(self):
        if not isinstance(self.node, ArrayNode):
            tmp = self.node
            self.node = self._new_node()
            self.node.args.arguments += [tmp]

    def _check_is_equal(self, node, value) -> bool:
        # Overwrite in derived class
        return False

    def _check_regex_matches(self, node, regex: str) -> bool:
        # Overwrite in derived class
        return False

    def get_node(self):
        if isinstance(self.node, ArrayNode):
            if len(self.node.args.arguments) == 1:
                return self.node.args.arguments[0]
        return self.node

    def supported_element_nodes(self):
        # Overwrite in derived class
        return []

    def supported_nodes(self):
        return [ArrayNode] + self.supported_element_nodes()

    def set_value(self, value):
        if not isinstance(value, list):
            value = [value]
        self._ensure_array_node()
        self.node.args.arguments = [] # Remove all current nodes
        for i in value:
            self.node.args.arguments += [self._new_element_node(i)]

    def add_value(self, value):
        if not isinstance(value, list):
            value = [value]
        self._ensure_array_node()
        for i in value:
            self.node.args.arguments += [self._new_element_node(i)]

    def _remove_helper(self, value, equal_func):
        def check_remove_node(node):
            for j in value:
                if equal_func(i, j):
                    return True
            return False

        if not isinstance(value, list):
            value = [value]
        self._ensure_array_node()
        removed_list = []
        for i in self.node.args.arguments:
            if not check_remove_node(i):
                removed_list += [i]
        self.node.args.arguments = removed_list

    def remove_value(self, value):
        self._remove_helper(value, self._check_is_equal)

    def remove_regex(self, regex: str):
        self._remove_helper(regex, self._check_regex_matches)

class MTypeStrList(MTypeList):
    def __init__(self, node: Optional[BaseNode] = None):
        super().__init__(node)

    def _new_element_node(self, value):
        return StringNode(Token('', '', 0, 0, 0, None, str(value)))

    def _check_is_equal(self, node, value) -> bool:
        if isinstance(node, StringNode):
            return node.value == value
        return False

    def _check_regex_matches(self, node, regex: str) -> bool:
        if isinstance(node, StringNode):
            return re.match(regex, node.value) is not None
        return False

    def supported_element_nodes(self):
        return [StringNode]

class MTypeIDList(MTypeList):
    def __init__(self, node: Optional[BaseNode] = None):
        super().__init__(node)

    def _new_element_node(self, value):
        return IdNode(Token('', '', 0, 0, 0, None, str(value)))

    def _check_is_equal(self, node, value) -> bool:
        if isinstance(node, IdNode):
            return node.value == value
        return False

    def _check_regex_matches(self, node, regex: str) -> bool:
        if isinstance(node, StringNode):
            return re.match(regex, node.value) is not None
        return False

    def supported_element_nodes(self):
        return [IdNode]

rewriter_keys = {
    'default_options': {
        'operation': (str, None, ['set', 'delete']),
        'options': (dict, {}, None)
    },
    'kwargs': {
        'function': (str, None, None),
        'id': (str, None, None),
        'operation': (str, None, ['set', 'delete', 'add', 'remove', 'remove_regex', 'info']),
        'kwargs': (dict, {}, None)
    },
    'target': {
        'target': (str, None, None),
        'operation': (str, None, ['src_add', 'src_rm', 'target_rm', 'target_add', 'info']),
        'sources': (list, [], None),
        'subdir': (str, '', None),
        'target_type': (str, 'executable', ['both_libraries', 'executable', 'jar', 'library', 'shared_library', 'shared_module', 'static_library']),
    }
}

rewriter_func_kwargs = {
    'dependency': {
        'language': MTypeStr,
        'method': MTypeStr,
        'native': MTypeBool,
        'not_found_message': MTypeStr,
        'required': MTypeBool,
        'static': MTypeBool,
        'version': MTypeStrList,
        'modules': MTypeStrList
    },
    'target': {
        'build_by_default': MTypeBool,
        'build_rpath': MTypeStr,
        'dependencies': MTypeIDList,
        'gui_app': MTypeBool,
        'link_with': MTypeIDList,
        'export_dynamic': MTypeBool,
        'implib': MTypeBool,
        'install': MTypeBool,
        'install_dir': MTypeStr,
        'install_rpath': MTypeStr,
        'pie': MTypeBool
    },
    'project': {
        'default_options': MTypeStrList,
        'meson_version': MTypeStr,
        'license': MTypeStrList,
        'subproject_dir': MTypeStr,
        'version': MTypeStr
    }
}

class Rewriter:
    def __init__(self, sourcedir: str, generator: str = 'ninja', skip_errors: bool = False):
        self.sourcedir = sourcedir
        self.interpreter = IntrospectionInterpreter(sourcedir, '', generator, visitors = [AstIDGenerator(), AstIndentationGenerator(), AstConditionLevel()])
        self.skip_errors = skip_errors
        self.modefied_nodes = []
        self.to_remove_nodes = []
        self.to_add_nodes = []
        self.functions = {
            'default_options': self.process_default_options,
            'kwargs': self.process_kwargs,
            'target': self.process_target,
        }
        self.info_dump = None

    def analyze_meson(self):
        mlog.log('Analyzing meson file:', mlog.bold(os.path.join(self.sourcedir, environment.build_filename)))
        self.interpreter.analyze()
        mlog.log('  -- Project:', mlog.bold(self.interpreter.project_data['descriptive_name']))
        mlog.log('  -- Version:', mlog.cyan(self.interpreter.project_data['version']))

    def add_info(self, cmd_type: str, cmd_id: str, data: dict):
        if self.info_dump is None:
            self.info_dump = {}
        if cmd_type not in self.info_dump:
            self.info_dump[cmd_type] = {}
        self.info_dump[cmd_type][cmd_id] = data

    def print_info(self):
        if self.info_dump is None:
            return
        sys.stderr.write(json.dumps(self.info_dump, indent=2))

    def on_error(self):
        if self.skip_errors:
            return mlog.cyan('-->'), mlog.yellow('skipping')
        return mlog.cyan('-->'), mlog.red('aborting')

    def handle_error(self):
        if self.skip_errors:
            return None
        raise MesonException('Rewriting the meson.build failed')

    def find_target(self, target: str):
        def check_list(name: str) -> List[BaseNode]:
            result = []
            for i in self.interpreter.targets:
                if name == i['name'] or name == i['id']:
                    result += [i]
            return result

        targets = check_list(target)
        if targets:
            if len(targets) == 1:
                return targets[0]
            else:
                mlog.error('There are multiple targets matching', mlog.bold(target))
                for i in targets:
                    mlog.error('  -- Target name', mlog.bold(i['name']), 'with ID', mlog.bold(i['id']))
                mlog.error('Please try again with the unique ID of the target', *self.on_error())
                self.handle_error()
                return None

        # Check the assignments
        tgt = None
        if target in self.interpreter.assignments:
            node = self.interpreter.assignments[target][0]
            if isinstance(node, FunctionNode):
                if node.func_name in ['executable', 'jar', 'library', 'shared_library', 'shared_module', 'static_library', 'both_libraries']:
                    tgt = self.interpreter.assign_vals[target][0]

        return tgt

    def find_dependency(self, dependency: str):
        def check_list(name: str):
            for i in self.interpreter.dependencies:
                if name == i['name']:
                    return i
            return None

        dep = check_list(dependency)
        if dep is not None:
            return dep

        # Check the assignments
        if dependency in self.interpreter.assignments:
            node = self.interpreter.assignments[dependency][0]
            if isinstance(node, FunctionNode):
                if node.func_name in ['dependency']:
                    name = self.interpreter.flatten_args(node.args)[0]
                    dep = check_list(name)

        return dep

    @RequiredKeys(rewriter_keys['default_options'])
    def process_default_options(self, cmd):
        # First, remove the old values
        kwargs_cmd = {
            'function': 'project',
            'id': "/",
            'operation': 'remove_regex',
            'kwargs': {
                'default_options': ['{}=.*'.format(x) for x in cmd['options'].keys()]
            }
        }
        self.process_kwargs(kwargs_cmd)

        # Then add the new values
        if cmd['operation'] != 'set':
            return

        kwargs_cmd['operation'] = 'add'
        kwargs_cmd['kwargs']['default_options'] = []

        cdata = self.interpreter.coredata
        options = {
            **cdata.builtins,
            **cdata.builtins_per_machine.host,
            **{'build.' + k: o for k, o in cdata.builtins_per_machine.build.items()},
            **cdata.backend_options,
            **cdata.base_options,
            **cdata.compiler_options.host,
            **{'build.' + k: o for k, o in cdata.compiler_options.build.items()},
            **cdata.user_options,
        }

        for key, val in sorted(cmd['options'].items()):
            if key not in options:
                mlog.error('Unknown options', mlog.bold(key), *self.on_error())
                self.handle_error()
                continue

            try:
                val = options[key].validate_value(val)
            except MesonException as e:
                mlog.error('Unable to set', mlog.bold(key), mlog.red(str(e)), *self.on_error())
                self.handle_error()
                continue

            kwargs_cmd['kwargs']['default_options'] += ['{}={}'.format(key, val)]

        self.process_kwargs(kwargs_cmd)

    @RequiredKeys(rewriter_keys['kwargs'])
    def process_kwargs(self, cmd):
        mlog.log('Processing function type', mlog.bold(cmd['function']), 'with id', mlog.cyan("'" + cmd['id'] + "'"))
        if cmd['function'] not in rewriter_func_kwargs:
            mlog.error('Unknown function type', cmd['function'], *self.on_error())
            return self.handle_error()
        kwargs_def = rewriter_func_kwargs[cmd['function']]

        # Find the function node to modify
        node = None
        arg_node = None
        if cmd['function'] == 'project':
            if cmd['id'] != '/':
                mlog.error('The ID for the function type project must be "/"', *self.on_error())
                return self.handle_error()
            node = self.interpreter.project_node
            arg_node = node.args
        elif cmd['function'] == 'target':
            tmp = self.find_target(cmd['id'])
            if tmp:
                node = tmp['node']
                arg_node = node.args
        elif cmd['function'] == 'dependency':
            tmp = self.find_dependency(cmd['id'])
            if tmp:
                node = tmp['node']
                arg_node = node.args
        if not node:
            mlog.error('Unable to find the function node')
        assert(isinstance(node, FunctionNode))
        assert(isinstance(arg_node, ArgumentNode))

        # Print kwargs info
        if cmd['operation'] == 'info':
            info_data = {}
            for key, val in sorted(arg_node.kwargs.items()):
                info_data[key] = None
                if isinstance(val, ElementaryNode):
                    info_data[key] = val.value
                elif isinstance(val, ArrayNode):
                    data_list = []
                    for i in val.args.arguments:
                        element = None
                        if isinstance(i, ElementaryNode):
                            element = i.value
                        data_list += [element]
                    info_data[key] = data_list

            self.add_info('kwargs', '{}#{}'.format(cmd['function'], cmd['id']), info_data)
            return # Nothing else to do

        # Modify the kwargs
        num_changed = 0
        for key, val in sorted(cmd['kwargs'].items()):
            if key not in kwargs_def:
                mlog.error('Cannot modify unknown kwarg', mlog.bold(key), *self.on_error())
                self.handle_error()
                continue

            # Remove the key from the kwargs
            if cmd['operation'] == 'delete':
                if key in arg_node.kwargs:
                    mlog.log('  -- Deleting', mlog.bold(key), 'from the kwargs')
                    del arg_node.kwargs[key]
                    num_changed += 1
                else:
                    mlog.log('  -- Key', mlog.bold(key), 'is already deleted')
                continue

            if key not in arg_node.kwargs:
                arg_node.kwargs[key] = None
            modifyer = kwargs_def[key](arg_node.kwargs[key])
            if not modifyer.can_modify():
                mlog.log('  -- Skipping', mlog.bold(key), 'because it is to complex to modify')

            # Apply the operation
            val_str = str(val)
            if cmd['operation'] == 'set':
                mlog.log('  -- Setting', mlog.bold(key), 'to', mlog.yellow(val_str))
                modifyer.set_value(val)
            elif cmd['operation'] == 'add':
                mlog.log('  -- Adding', mlog.yellow(val_str), 'to', mlog.bold(key))
                modifyer.add_value(val)
            elif cmd['operation'] == 'remove':
                mlog.log('  -- Removing', mlog.yellow(val_str), 'from', mlog.bold(key))
                modifyer.remove_value(val)
            elif cmd['operation'] == 'remove_regex':
                mlog.log('  -- Removing all values matching', mlog.yellow(val_str), 'from', mlog.bold(key))
                modifyer.remove_regex(val)

            # Write back the result
            arg_node.kwargs[key] = modifyer.get_node()
            num_changed += 1

        if num_changed > 0 and node not in self.modefied_nodes:
            self.modefied_nodes += [node]

    def find_assignment_node(self, node: BaseNode) -> AssignmentNode:
        if hasattr(node, 'ast_id') and node.ast_id in self.interpreter.reverse_assignment:
            return self.interpreter.reverse_assignment[node.ast_id]
        return None

    @RequiredKeys(rewriter_keys['target'])
    def process_target(self, cmd):
        mlog.log('Processing target', mlog.bold(cmd['target']), 'operation', mlog.cyan(cmd['operation']))
        target = self.find_target(cmd['target'])
        if target is None and cmd['operation'] != 'target_add':
            mlog.error('Unknown target', mlog.bold(cmd['target']), *self.on_error())
            return self.handle_error()

        # Make source paths relative to the current subdir
        def rel_source(src: str) -> str:
            subdir = os.path.abspath(os.path.join(self.sourcedir, target['subdir']))
            if os.path.isabs(src):
                return os.path.relpath(src, subdir)
            elif not os.path.exists(src):
                return src # Trust the user when the source doesn't exist
            # Make sure that the path is relative to the subdir
            return os.path.relpath(os.path.abspath(src), subdir)

        if target is not None:
            cmd['sources'] = [rel_source(x) for x in cmd['sources']]

        # Utility function to get a list of the sources from a node
        def arg_list_from_node(n):
            args = []
            if isinstance(n, FunctionNode):
                args = list(n.args.arguments)
                if n.func_name in build_target_functions:
                    args.pop(0)
            elif isinstance(n, ArrayNode):
                args = n.args.arguments
            elif isinstance(n, ArgumentNode):
                args = n.arguments
            return args

        to_sort_nodes = []

        if cmd['operation'] == 'src_add':
            node = None
            if target['sources']:
                node = target['sources'][0]
            else:
                node = target['node']
            assert(node is not None)

            # Generate the current source list
            src_list = []
            for i in target['sources']:
                for j in arg_list_from_node(i):
                    if isinstance(j, StringNode):
                        src_list += [j.value]

            # Generate the new String nodes
            to_append = []
            for i in sorted(set(cmd['sources'])):
                if i in src_list:
                    mlog.log('  -- Source', mlog.green(i), 'is already defined for the target --> skipping')
                    continue
                mlog.log('  -- Adding source', mlog.green(i), 'at',
                         mlog.yellow('{}:{}'.format(os.path.join(node.subdir, environment.build_filename), node.lineno)))
                token = Token('string', node.subdir, 0, 0, 0, None, i)
                to_append += [StringNode(token)]

            # Append to the AST at the right place
            arg_node = None
            if isinstance(node, (FunctionNode, ArrayNode)):
                arg_node = node.args
            elif isinstance(node, ArgumentNode):
                arg_node = node
            assert(arg_node is not None)
            arg_node.arguments += to_append

            # Mark the node as modified
            if arg_node not in to_sort_nodes and not isinstance(node, FunctionNode):
                to_sort_nodes += [arg_node]
            if node not in self.modefied_nodes:
                self.modefied_nodes += [node]

        elif cmd['operation'] == 'src_rm':
            # Helper to find the exact string node and its parent
            def find_node(src):
                for i in target['sources']:
                    for j in arg_list_from_node(i):
                        if isinstance(j, StringNode):
                            if j.value == src:
                                return i, j
                return None, None

            for i in cmd['sources']:
                # Try to find the node with the source string
                root, string_node = find_node(i)
                if root is None:
                    mlog.warning('  -- Unable to find source', mlog.green(i), 'in the target')
                    continue

                # Remove the found string node from the argument list
                arg_node = None
                if isinstance(root, (FunctionNode, ArrayNode)):
                    arg_node = root.args
                elif isinstance(root, ArgumentNode):
                    arg_node = root
                assert(arg_node is not None)
                mlog.log('  -- Removing source', mlog.green(i), 'from',
                         mlog.yellow('{}:{}'.format(os.path.join(string_node.subdir, environment.build_filename), string_node.lineno)))
                arg_node.arguments.remove(string_node)

                # Mark the node as modified
                if arg_node not in to_sort_nodes and not isinstance(root, FunctionNode):
                    to_sort_nodes += [arg_node]
                if root not in self.modefied_nodes:
                    self.modefied_nodes += [root]

        elif cmd['operation'] == 'target_add':
            if target is not None:
                mlog.error('Can not add target', mlog.bold(cmd['target']), 'because it already exists', *self.on_error())
                return self.handle_error()

            id_base = re.sub(r'[- ]', '_', cmd['target'])
            target_id = id_base + '_exe' if cmd['target_type'] == 'executable' else '_lib'
            source_id = id_base + '_sources'

            # Build src list
            src_arg_node = ArgumentNode(Token('string', cmd['subdir'], 0, 0, 0, None, ''))
            src_arr_node = ArrayNode(src_arg_node, 0, 0, 0, 0)
            src_far_node = ArgumentNode(Token('string', cmd['subdir'], 0, 0, 0, None, ''))
            src_fun_node = FunctionNode(cmd['subdir'], 0, 0, 0, 0, 'files', src_far_node)
            src_ass_node = AssignmentNode(cmd['subdir'], 0, 0, source_id, src_fun_node)
            src_arg_node.arguments = [StringNode(Token('string', cmd['subdir'], 0, 0, 0, None, x)) for x in cmd['sources']]
            src_far_node.arguments = [src_arr_node]

            # Build target
            tgt_arg_node = ArgumentNode(Token('string', cmd['subdir'], 0, 0, 0, None, ''))
            tgt_fun_node = FunctionNode(cmd['subdir'], 0, 0, 0, 0, cmd['target_type'], tgt_arg_node)
            tgt_ass_node = AssignmentNode(cmd['subdir'], 0, 0, target_id, tgt_fun_node)
            tgt_arg_node.arguments = [
                StringNode(Token('string', cmd['subdir'], 0, 0, 0, None, cmd['target'])),
                IdNode(Token('string', cmd['subdir'], 0, 0, 0, None, source_id))
            ]

            src_ass_node.accept(AstIndentationGenerator())
            tgt_ass_node.accept(AstIndentationGenerator())
            self.to_add_nodes += [src_ass_node, tgt_ass_node]

        elif cmd['operation'] == 'target_rm':
            to_remove = self.find_assignment_node(target['node'])
            if to_remove is None:
                to_remove = target['node']
            self.to_remove_nodes += [to_remove]
            mlog.log('  -- Removing target', mlog.green(cmd['target']), 'at',
                     mlog.yellow('{}:{}'.format(os.path.join(to_remove.subdir, environment.build_filename), to_remove.lineno)))

        elif cmd['operation'] == 'info':
            # List all sources in the target
            src_list = []
            for i in target['sources']:
                for j in arg_list_from_node(i):
                    if isinstance(j, StringNode):
                        src_list += [j.value]
            test_data = {
                'name': target['name'],
                'sources': src_list
            }
            self.add_info('target', target['id'], test_data)

        # Sort files
        for i in to_sort_nodes:
            convert = lambda text: int(text) if text.isdigit() else text.lower()
            alphanum_key = lambda key: [convert(c) for c in re.split('([0-9]+)', key)]
            path_sorter = lambda key: ([(key.count('/') <= idx, alphanum_key(x)) for idx, x in enumerate(key.split('/'))])

            unknown = [x for x in i.arguments if not isinstance(x, StringNode)]
            sources = [x for x in i.arguments if isinstance(x, StringNode)]
            sources = sorted(sources, key=lambda x: path_sorter(x.value))
            i.arguments = unknown + sources

    def process(self, cmd):
        if 'type' not in cmd:
            raise RewriterException('Command has no key "type"')
        if cmd['type'] not in self.functions:
            raise RewriterException('Unknown command "{}". Supported commands are: {}'
                                    .format(cmd['type'], list(self.functions.keys())))
        self.functions[cmd['type']](cmd)

    def apply_changes(self):
        assert(all(hasattr(x, 'lineno') and hasattr(x, 'colno') and hasattr(x, 'subdir') for x in self.modefied_nodes))
        assert(all(hasattr(x, 'lineno') and hasattr(x, 'colno') and hasattr(x, 'subdir') for x in self.to_remove_nodes))
        assert(all(isinstance(x, (ArrayNode, FunctionNode)) for x in self.modefied_nodes))
        assert(all(isinstance(x, (ArrayNode, AssignmentNode, FunctionNode)) for x in self.to_remove_nodes))
        # Sort based on line and column in reversed order
        work_nodes = [{'node': x, 'action': 'modify'} for x in self.modefied_nodes]
        work_nodes += [{'node': x, 'action': 'rm'} for x in self.to_remove_nodes]
        work_nodes = list(sorted(work_nodes, key=lambda x: (x['node'].lineno, x['node'].colno), reverse=True))
        work_nodes += [{'node': x, 'action': 'add'} for x in self.to_add_nodes]

        # Generating the new replacement string
        str_list = []
        for i in work_nodes:
            new_data = ''
            if i['action'] == 'modify' or i['action'] == 'add':
                printer = AstPrinter()
                i['node'].accept(printer)
                printer.post_process()
                new_data = printer.result.strip()
            data = {
                'file': os.path.join(i['node'].subdir, environment.build_filename),
                'str': new_data,
                'node': i['node'],
                'action': i['action']
            }
            str_list += [data]

        # Load build files
        files = {}
        for i in str_list:
            if i['file'] in files:
                continue
            fpath = os.path.realpath(os.path.join(self.sourcedir, i['file']))
            fdata = ''
            # Create an empty file if it does not exist
            if not os.path.exists(fpath):
                with open(fpath, 'w'):
                    pass
            with open(fpath, 'r') as fp:
                fdata = fp.read()

            # Generate line offsets numbers
            m_lines = fdata.splitlines(True)
            offset = 0
            line_offsets = []
            for j in m_lines:
                line_offsets += [offset]
                offset += len(j)

            files[i['file']] = {
                'path': fpath,
                'raw': fdata,
                'offsets': line_offsets
            }

        # Replace in source code
        def remove_node(i):
            offsets = files[i['file']]['offsets']
            raw = files[i['file']]['raw']
            node = i['node']
            line = node.lineno - 1
            col = node.colno
            start = offsets[line] + col
            end = start
            if isinstance(node, (ArrayNode, FunctionNode)):
                end = offsets[node.end_lineno - 1] + node.end_colno

            # Only removal is supported for assignments
            elif isinstance(node, AssignmentNode) and i['action'] == 'rm':
                if isinstance(node.value, (ArrayNode, FunctionNode)):
                    remove_node({'file': i['file'], 'str': '', 'node': node.value, 'action': 'rm'})
                    raw = files[i['file']]['raw']
                while raw[end] != '=':
                    end += 1
                end += 1 # Handle the '='
                while raw[end] in [' ', '\n', '\t']:
                    end += 1

            files[i['file']]['raw'] = raw[:start] + i['str'] + raw[end:]

        for i in str_list:
            if i['action'] in ['modify', 'rm']:
                remove_node(i)
            elif i['action'] in ['add']:
                files[i['file']]['raw'] += i['str'] + '\n'

        # Write the files back
        for key, val in files.items():
            mlog.log('Rewriting', mlog.yellow(key))
            with open(val['path'], 'w') as fp:
                fp.write(val['raw'])

target_operation_map = {
    'add': 'src_add',
    'rm': 'src_rm',
    'add_target': 'target_add',
    'rm_target': 'target_rm',
    'info': 'info',
}

def list_to_dict(in_list: List[str]) -> Dict[str, str]:
    result = {}
    it = iter(in_list)
    try:
        for i in it:
            # calling next(it) is not a mistake, we're taking the next element from
            # the iterator, avoiding the need to preprocess it into a sequence of
            # key value pairs.
            result[i] = next(it)
    except StopIteration:
        raise TypeError('in_list parameter of list_to_dict must have an even length.')
    return result

def generate_target(options) -> List[dict]:
    return [{
        'type': 'target',
        'target': options.target,
        'operation': target_operation_map[options.operation],
        'sources': options.sources,
        'subdir': options.subdir,
        'target_type': options.tgt_type,
    }]

def generate_kwargs(options) -> List[dict]:
    return [{
        'type': 'kwargs',
        'function': options.function,
        'id': options.id,
        'operation': options.operation,
        'kwargs': list_to_dict(options.kwargs),
    }]

def generate_def_opts(options) -> List[dict]:
    return [{
        'type': 'default_options',
        'operation': options.operation,
        'options': list_to_dict(options.options),
    }]

def genreate_cmd(options) -> List[dict]:
    if os.path.exists(options.json):
        with open(options.json, 'r') as fp:
            return json.load(fp)
    else:
        return json.loads(options.json)

# Map options.type to the actual type name
cli_type_map = {
    'target': generate_target,
    'tgt': generate_target,
    'kwargs': generate_kwargs,
    'default-options': generate_def_opts,
    'def': generate_def_opts,
    'command': genreate_cmd,
    'cmd': genreate_cmd,
}

def run(options):
    if not options.verbose:
        mlog.set_quiet()

    try:
        rewriter = Rewriter(options.sourcedir, skip_errors=options.skip)
        rewriter.analyze_meson()

        if options.type is None:
            mlog.error('No command specified')
            return 1

        commands = cli_type_map[options.type](options)

        if not isinstance(commands, list):
            raise TypeError('Command is not a list')

        for i in commands:
            if not isinstance(i, object):
                raise TypeError('Command is not an object')
            rewriter.process(i)

        rewriter.apply_changes()
        rewriter.print_info()
        return 0
    except Exception as e:
        raise e
    finally:
        mlog.set_verbose()