from __future__ import annotations

from dataclasses import dataclass, field
from typing import Any


@dataclass
class ConfigAdapterResult:
    config: dict[str, Any]
    warnings: list[str] = field(default_factory=list)
    migrated_fields: list[str] = field(default_factory=list)


def adapt_config(config: dict[str, Any] | None) -> ConfigAdapterResult:
    if not config:
        return ConfigAdapterResult(config={})

    result = ConfigAdapterResult(config=dict(config))

    _adapt_streaming(result)
    _adapt_security(result)
    _adapt_capabilities(result)
    _adapt_dm_scope(result)

    return result


def _adapt_streaming(result: ConfigAdapterResult) -> None:
    streaming = result.config.get("streaming", {})
    if isinstance(streaming, str):
        result.config["streaming"] = {"mode": streaming}
        result.warnings.append("streaming config was a string, converted to {mode: ...}")
        result.migrated_fields.append("streaming")

    legacy_stream = result.config.pop("streamMode_ENABLED", None)
    if legacy_stream is not None:
        result.config.setdefault("streaming", {})
        if isinstance(result.config["streaming"], str):
            result.config["streaming"] = {"mode": result.config["streaming"]}
        result.config["streaming"]["mode"] = "auto"
        result.warnings.append("Legacy streamMode_ENABLED migrated to streaming.mode=auto")
        result.migrated_fields.append("streamMode_ENABLED")


def _adapt_security(result: ConfigAdapterResult) -> None:
    security = result.config.get("security", {})
    if isinstance(security, str):
        result.config["security"] = {"mode": security}
        result.warnings.append("security config was a string, converted to object")
        result.migrated_fields.append("security")


def _adapt_capabilities(result: ConfigAdapterResult) -> None:
    legacy_exec_approvals = result.config.pop("execApprovalsEnabled", None)
    if legacy_exec_approvals is not None:
        caps = result.config.setdefault("capabilities", {})
        caps["execApprovals"] = bool(legacy_exec_approvals)
        result.warnings.append("Legacy execApprovalsEnabled migrated to capabilities.execApprovals")
        result.migrated_fields.append("execApprovalsEnabled")


def _adapt_dm_scope(result: ConfigAdapterResult) -> None:
    legacy_dm = result.config.pop("dm_chat", None)
    if legacy_dm is not None:
        result.config["dm_scope"] = legacy_dm
        result.warnings.append("Legacy dm_chat migrated to dm_scope")
        result.migrated_fields.append("dm_chat")