"""Tests for PluginRegistry aggregation and singleton behavior."""
import json
from pathlib import Path

import pytest

from pyra.plugins.base import BasePlugin, Tool
from pyra.plugins.registry import PluginRegistry


def _make_plugin_dir(plugins_dir: Path, name: str, plugin_code: str) -> None:
    d = plugins_dir / name
    d.mkdir(parents=True)
    (d / "manifest.json").write_text(json.dumps({"name": name, "version": "1.0.0"}))
    (d / "plugin.py").write_text(plugin_code)


_ALPHA_PLUGIN = """\
from pyra.plugins.base import BasePlugin, Tool

class _P(BasePlugin):
    name = "alpha"
    description = "Alpha plugin"
    version = "1.0.0"

    def tools(self):
        return [
            Tool("alpha_tool", "An alpha tool",
                 {"type": "object", "properties": {}},
                 lambda: "alpha result", requires_approval=False)
        ]

    def slash_commands(self):
        return {"/alpha": lambda: None}

    def system_prompt_addition(self):
        return "Alpha is active."

def get_plugin():
    return _P()
"""

_BETA_PLUGIN = """\
from pyra.plugins.base import BasePlugin, Tool

class _P(BasePlugin):
    name = "beta"
    description = "Beta plugin"
    version = "1.0.0"

    def tools(self):
        return [
            Tool("beta_tool", "A beta tool",
                 {"type": "object", "properties": {}},
                 lambda: "beta result", requires_approval=True)
        ]

    def system_prompt_addition(self):
        return "Beta is active."

def get_plugin():
    return _P()
"""


def test_singleton_returns_same_instance(tmp_pyra_home):
    r1 = PluginRegistry.instance()
    r2 = PluginRegistry.instance()
    assert r1 is r2


def test_load_all_only_loads_enabled(tmp_pyra_home, tmp_path):
    plugins_dir = tmp_path / "plugins"
    plugins_dir.mkdir()
    _make_plugin_dir(plugins_dir, "alpha", _ALPHA_PLUGIN)
    _make_plugin_dir(plugins_dir, "beta", _BETA_PLUGIN)

    registry = PluginRegistry.instance()
    registry.load_all(plugins_dir, enabled_names=["alpha"])

    names = {p.name for p in registry.get_active_plugins()}
    assert "alpha" in names
    assert "beta" not in names


def test_get_all_tools_aggregates(tmp_pyra_home, tmp_path):
    plugins_dir = tmp_path / "plugins"
    plugins_dir.mkdir()
    _make_plugin_dir(plugins_dir, "alpha", _ALPHA_PLUGIN)
    _make_plugin_dir(plugins_dir, "beta", _BETA_PLUGIN)

    registry = PluginRegistry.instance()
    registry.load_all(plugins_dir, enabled_names=["alpha", "beta"])

    tool_names = {t.name for t in registry.get_all_tools()}
    assert "alpha_tool" in tool_names
    assert "beta_tool" in tool_names


def test_get_slash_commands_aggregates(tmp_pyra_home, tmp_path):
    plugins_dir = tmp_path / "plugins"
    plugins_dir.mkdir()
    _make_plugin_dir(plugins_dir, "alpha", _ALPHA_PLUGIN)

    registry = PluginRegistry.instance()
    registry.load_all(plugins_dir, enabled_names=["alpha"])

    cmds = registry.get_slash_commands()
    assert "/alpha" in cmds


def test_get_system_prompt_additions(tmp_pyra_home, tmp_path):
    plugins_dir = tmp_path / "plugins"
    plugins_dir.mkdir()
    _make_plugin_dir(plugins_dir, "alpha", _ALPHA_PLUGIN)
    _make_plugin_dir(plugins_dir, "beta", _BETA_PLUGIN)

    registry = PluginRegistry.instance()
    registry.load_all(plugins_dir, enabled_names=["alpha", "beta"])

    additions = registry.get_system_prompt_additions()
    assert "Alpha is active." in additions
    assert "Beta is active." in additions


def test_find_tool_returns_correct_tool(tmp_pyra_home, tmp_path):
    plugins_dir = tmp_path / "plugins"
    plugins_dir.mkdir()
    _make_plugin_dir(plugins_dir, "alpha", _ALPHA_PLUGIN)

    registry = PluginRegistry.instance()
    registry.load_all(plugins_dir, enabled_names=["alpha"])

    tool = registry.find_tool("alpha_tool")
    assert tool is not None
    assert tool.name == "alpha_tool"


def test_find_tool_unknown_returns_none(tmp_pyra_home):
    registry = PluginRegistry.instance()
    registry.load_all(Path("/nonexistent"), enabled_names=[])
    assert registry.find_tool("no_such_tool") is None


def test_empty_registry_returns_empty_collections(tmp_pyra_home):
    registry = PluginRegistry.instance()
    registry.load_all(Path("/nonexistent"), enabled_names=[])
    assert registry.get_all_tools() == []
    assert registry.get_slash_commands() == {}
    assert registry.get_system_prompt_additions() == ""
    assert registry.get_active_plugins() == []