from tclint.syntax_tree import Visitor, Command, BareWord, List
import lsprotocol.types as lsp
from common.load_data import standard_items

BUILTIN_VAR_LABELS = {ci.label for ci in standard_items.nx_variables}


class CompletionItems:
    def __init__(self):
        self._custom_functions: list[lsp.CompletionItem] = []

    @property
    def custom_functions(self) -> list[lsp.CompletionItem]:
        return self._custom_functions

    @custom_functions.setter
    def custom_functions(self, value: lsp.CompletionItem):
        self._custom_functions.append(value)


class _Completion(Visitor):
    def __init__(self):
        super().__init__()
        self._custom_functions: list[lsp.CompletionItem] = []
        self._proc_signatures = {}

    @property
    def custom_functions(self) -> list[lsp.CompletionItem]:
        return self._custom_functions

    @property
    def proc_signatures(self):
        return self._proc_signatures

    def reset(self):
        self._custom_functions = []
        self._proc_signatures = {}

    def _append_unique(self, item: lsp.CompletionItem):
        # Avoid duplicate labels within the same file scan
        if not any(ci.label == item.label for ci in self._custom_functions):
            # For functions, attach a command to trigger signature help after completion
            if item.kind == lsp.CompletionItemKind.Function and item.command is None:
                item.command = lsp.Command(title="Trigger Signature Help", command="editor.action.triggerParameterHints")
            self._custom_functions.append(item)

    def visit_command(self, command: Command):
        routine = command.routine

        # Collect custom proc names and their signatures
        if routine.contents == "proc" and command.args:
            first_arg = command.args[0]
            if not getattr(first_arg, "value", None):
                return

            if any(item.label == first_arg.value for item in standard_items.nx_procs):
                return

            # Record proc name as a completion item
            self._append_unique(lsp.CompletionItem(label=first_arg.value, kind=lsp.CompletionItemKind.Function))
            if len(command.args) < 2:
                return

            param_list_node = command.args[1]
            if not hasattr(param_list_node, "children"):
                return

            param_names = []
            for arg in param_list_node.children:
                if isinstance(arg, BareWord):
                    param_names.append(arg.value)
                elif isinstance(arg, List) and len(arg.children) >= 1:
                    first = arg.children[0]
                    if isinstance(first, BareWord):
                        param_names.append(first.value)

            self._proc_signatures[first_arg.value] = param_names

        # Collect global variables declared with: global var1 var2 ...
        elif routine.contents == "global" and command.args:
            for arg in command.args:
                if isinstance(arg, BareWord) and getattr(arg, "value", None):
                    if arg.value not in BUILTIN_VAR_LABELS:
                        self._append_unique(lsp.CompletionItem(label=arg.value, kind=lsp.CompletionItemKind.Variable))

        # Collect variables set with explicit global namespace: set ::var_name ...
        elif routine.contents == "set" and command.args:
            first = command.args[0]
            if isinstance(first, BareWord) and getattr(first, "value", None):
                var_name = first.value
                if var_name.startswith("::"):
                    base_name = var_name.split("(", 1)[0]
                    clean_name = base_name[2:]  # remove leading '::' for completion display
                    if clean_name not in BUILTIN_VAR_LABELS:
                        self._append_unique(lsp.CompletionItem(label=clean_name, kind=lsp.CompletionItemKind.Variable))


def remove_existing_items(items: list[lsp.CompletionItem], store: dict) -> None:
    """
    Entfernt alle CompletionItems aus dem store, deren label in der items-Liste vorkommt.
    Änderungen erfolgen in-place.
    """
    labels_to_remove = {item.label for item in items}

    for key in list(store.keys()):
        filtered = [ci for ci in store[key] if ci.label not in labels_to_remove]
        if filtered:
            store[key] = filtered
        else:
            del store[key]


def remove_shared_keys(nested_dict: dict[str, dict[str, list]], flat_dict: dict[str, list]) -> None:
    """
    Entfernt alle Keys aus nested_dict[file][func], wenn func auch in flat_dict vorhanden ist.
    Änderungen erfolgen in-place.
    """
    for file_path, func_dict in list(nested_dict.items()):
        for func_name in list(func_dict.keys()):
            if func_name in flat_dict:
                del nested_dict[file_path][func_name]

        if not nested_dict[file_path]:
            del nested_dict[file_path]


completion = _Completion()