"""Tests for CodexAppServerSession — drive turns through a mock client.

The session adapter has the most complex behavior of the three new modules:
notification draining, server-request handling (approvals), interrupt,
deadline timeouts. These tests pin all of that without spawning real codex.
"""

from __future__ import annotations

import threading
import time
from typing import Any, Optional

import pytest

from agent.transports.codex_app_server_session import (
    CodexAppServerSession,
    TurnResult,
    _ServerRequestRouting,
    _approval_choice_to_codex_decision,
)


class FakeClient:
    """Stand-in for CodexAppServerClient that records calls and lets the test
    drive the notification / server-request streams synchronously."""

    def __init__(self, *, codex_bin: str = "codex", codex_home=None) -> None:
        self.codex_bin = codex_bin
        self.codex_home = codex_home
        self.requests: list[tuple[str, dict]] = []
        self.notifications_responses: list[dict] = []
        self.responses: list[tuple[Any, dict]] = []
        self.error_responses: list[tuple[Any, int, str]] = []
        self._initialized = False
        self._closed = False
        self._notifications: list[dict] = []
        self._server_requests: list[dict] = []
        self._request_handler = None  # Optional[Callable[[str, dict], dict]]

    # API matching CodexAppServerClient
    def initialize(self, **kwargs):
        self._initialized = True
        return {"userAgent": "fake/0.0.0", "codexHome": "/tmp",
                "platformOs": "linux", "platformFamily": "unix"}

    def request(self, method: str, params: Optional[dict] = None, timeout: float = 30.0):
        self.requests.append((method, params or {}))
        if self._request_handler is not None:
            return self._request_handler(method, params or {})
        # Sensible defaults for protocol methods used by the session
        if method == "thread/start":
            return {"thread": {"id": "thread-fake-001"},
                    "activePermissionProfile": {"id": "workspace-write"}}
        if method == "turn/start":
            return {"turn": {"id": "turn-fake-001"}}
        if method == "turn/interrupt":
            return {}
        return {}

    def notify(self, method: str, params=None):
        pass

    def respond(self, request_id, result):
        self.responses.append((request_id, result))

    def respond_error(self, request_id, code, message, data=None):
        self.error_responses.append((request_id, code, message))

    def take_notification(self, timeout: float = 0.0):
        if self._notifications:
            return self._notifications.pop(0)
        # Honor a tiny sleep so the loop doesn't hot-spin; the real client
        # blocks on a queue. For tests we want determinism.
        if timeout > 0:
            time.sleep(min(timeout, 0.001))
        return None

    def take_server_request(self, timeout: float = 0.0):
        if self._server_requests:
            return self._server_requests.pop(0)
        return None

    def close(self):
        self._closed = True

    # Test helpers
    def queue_notification(self, method: str, **params):
        self._notifications.append({"method": method, "params": params})

    def queue_server_request(self, method: str, request_id: Any = "srv-1", **params):
        self._server_requests.append({"id": request_id, "method": method, "params": params})


def make_session(client: FakeClient, **kwargs) -> CodexAppServerSession:
    return CodexAppServerSession(
        cwd="/tmp",
        client_factory=lambda **kw: client,
        **kwargs,
    )


# ---- choice mapping ----

class TestApprovalChoiceMapping:
    @pytest.mark.parametrize("choice,expected", [
        ("once", "accept"),
        ("session", "acceptForSession"),
        ("always", "acceptForSession"),
        ("deny", "decline"),
        ("anything-else", "decline"),
    ])
    def test_mapping(self, choice, expected):
        assert _approval_choice_to_codex_decision(choice) == expected


# ---- lifecycle ----

class TestLifecycle:
    def test_ensure_started_is_idempotent(self):
        client = FakeClient()
        s = make_session(client)
        tid_a = s.ensure_started()
        tid_b = s.ensure_started()
        assert tid_a == tid_b == "thread-fake-001"
        # thread/start should be called exactly once
        method_calls = [m for (m, _) in client.requests if m == "thread/start"]
        assert len(method_calls) == 1

    def test_thread_start_passes_cwd_only(self):
        """thread/start carries cwd. We intentionally do NOT pass `permissions`
        on this codex version (experimentalApi-gated + requires matching
        config.toml [permissions] table). Letting codex use its default
        (read-only unless user configures otherwise) is the documented path."""
        client = FakeClient()
        s = make_session(client, permission_profile="workspace-write")
        s.ensure_started()
        method, params = next(r for r in client.requests if r[0] == "thread/start")
        assert params["cwd"] == "/tmp"
        assert "permissions" not in params  # see session.ensure_started() comment

    def test_close_idempotent(self):
        client = FakeClient()
        s = make_session(client)
        s.ensure_started()
        s.close()
        s.close()
        assert client._closed is True


# ---- turn loop ----

class TestRunTurn:
    def test_simple_text_turn_returns_final_message(self):
        client = FakeClient()
        client.queue_notification("turn/started", threadId="t", turn={"id": "tu1"})
        client.queue_notification(
            "item/completed",
            item={"type": "agentMessage", "id": "m1", "text": "hello world"},
            threadId="t", turnId="tu1",
        )
        client.queue_notification(
            "turn/completed",
            threadId="t",
            turn={"id": "tu1", "status": "completed", "error": None},
        )
        s = make_session(client)
        r = s.run_turn("hi", turn_timeout=2.0)
        assert r.final_text == "hello world"
        assert r.interrupted is False
        assert r.error is None
        assert any(m["role"] == "assistant" and m.get("content") == "hello world"
                   for m in r.projected_messages)
        # turn_id propagated for downstream session-DB linkage
        assert r.turn_id == "turn-fake-001"

    def test_tool_iteration_counter_ticks(self):
        client = FakeClient()
        # Two completed exec items + one final agent message
        for i, item_id in enumerate(("ex1", "ex2"), start=1):
            client.queue_notification(
                "item/completed",
                item={
                    "type": "commandExecution", "id": item_id,
                    "command": f"cmd{i}", "cwd": "/tmp",
                    "status": "completed", "aggregatedOutput": "ok",
                    "exitCode": 0, "commandActions": [],
                },
                threadId="t", turnId="tu1",
            )
        client.queue_notification(
            "item/completed",
            item={"type": "agentMessage", "id": "m1", "text": "done"},
            threadId="t", turnId="tu1",
        )
        client.queue_notification(
            "turn/completed", threadId="t",
            turn={"id": "tu1", "status": "completed", "error": None},
        )
        s = make_session(client)
        r = s.run_turn("do stuff", turn_timeout=2.0)
        assert r.tool_iterations == 2
        # Each tool item produces (assistant, tool) — 2*2 + final assistant = 5 msgs
        assert len(r.projected_messages) == 5

    def test_turn_start_failure_returns_error(self):
        client = FakeClient()
        from agent.transports.codex_app_server import CodexAppServerError

        def boom(method, params):
            if method == "turn/start":
                raise CodexAppServerError(code=-32600, message="bad input")
            return {"thread": {"id": "t"}, "activePermissionProfile": {"id": "x"}}

        client._request_handler = boom
        s = make_session(client)
        r = s.run_turn("hi", turn_timeout=2.0)
        assert r.error is not None
        assert "bad input" in r.error
        assert r.final_text == ""

    def test_interrupt_during_turn_issues_turn_interrupt(self):
        client = FakeClient()
        # Don't queue turn/completed — the loop has to interrupt out
        client.queue_notification(
            "item/completed",
            item={"type": "commandExecution", "id": "x", "command": "sleep 60",
                  "cwd": "/", "status": "inProgress",
                  "aggregatedOutput": None, "exitCode": None,
                  "commandActions": []},
            threadId="t", turnId="tu1",
        )
        s = make_session(client)
        s.ensure_started()
        # Trip the interrupt before run_turn even consumes the notification.
        # The loop will see interrupt set on its first iteration and bail.
        s.request_interrupt()
        r = s.run_turn("loop forever", turn_timeout=2.0)
        assert r.interrupted is True
        # turn/interrupt was requested with the right turnId
        assert any(
            method == "turn/interrupt" and params.get("turnId") == "turn-fake-001"
            for (method, params) in client.requests
        )

    def test_deadline_exceeded_records_error(self):
        client = FakeClient()
        # No notifications and no completion → must hit deadline
        s = make_session(client)
        r = s.run_turn("never finishes", turn_timeout=0.05,
                       notification_poll_timeout=0.01)
        assert r.interrupted is True
        assert r.error and "timed out" in r.error

    def test_failed_turn_records_error_from_turn_completed(self):
        client = FakeClient()
        client.queue_notification(
            "turn/completed", threadId="t",
            turn={"id": "tu1", "status": "failed",
                  "error": {"message": "model error"}},
        )
        s = make_session(client)
        r = s.run_turn("x", turn_timeout=1.0)
        assert r.error and "model error" in r.error


# ---- approval bridge ----

class TestServerRequestRouting:
    def test_exec_approval_with_callback_approves_once(self):
        client = FakeClient()
        client.queue_server_request(
            "item/commandExecution/requestApproval", request_id="req-1",
            command="ls /tmp", cwd="/tmp",
        )
        client.queue_notification(
            "turn/completed", threadId="t",
            turn={"id": "tu1", "status": "completed", "error": None},
        )

        captured: dict = {}

        def cb(command, description, *, allow_permanent=True):
            captured["command"] = command
            captured["description"] = description
            return "once"

        s = make_session(client, approval_callback=cb)
        s.run_turn("hi", turn_timeout=1.0)
        assert captured["command"] == "ls /tmp"
        # The session must have responded to the server request with "accept"
        assert ("req-1", {"decision": "accept"}) in client.responses

    def test_exec_approval_no_callback_denies(self):
        client = FakeClient()
        client.queue_server_request("item/commandExecution/requestApproval", request_id="req-1",
                                    command="rm -rf /", cwd="/")
        client.queue_notification(
            "turn/completed", threadId="t",
            turn={"id": "tu1", "status": "completed", "error": None},
        )
        s = make_session(client)  # no approval_callback wired
        s.run_turn("hi", turn_timeout=1.0)
        assert ("req-1", {"decision": "decline"}) in client.responses

    def test_apply_patch_approval_session_maps_to_session_decision(self):
        client = FakeClient()
        client.queue_server_request(
            "item/fileChange/requestApproval", request_id="req-2",
            itemId="fc-1",
            turnId="t1",
            threadId="th",
            startedAtMs=1234567890,
            reason="create new file with hello() function",
        )
        client.queue_notification(
            "turn/completed", threadId="t",
            turn={"id": "tu1", "status": "completed", "error": None},
        )

        def cb(command, description, *, allow_permanent=True):
            return "session"

        s = make_session(client, approval_callback=cb)
        s.run_turn("hi", turn_timeout=1.0)
        assert ("req-2", {"decision": "acceptForSession"}) in client.responses

    def test_unknown_server_request_replied_with_error(self):
        client = FakeClient()
        client.queue_server_request("totally/unknown", request_id="req-3")
        client.queue_notification(
            "turn/completed", threadId="t",
            turn={"id": "tu1", "status": "completed", "error": None},
        )
        s = make_session(client)
        s.run_turn("hi", turn_timeout=1.0)
        assert any(
            rid == "req-3" and code == -32601
            for (rid, code, _msg) in client.error_responses
        )

    def test_mcp_elicitation_for_hermes_tools_auto_accepts(self):
        """When codex elicits on behalf of hermes-tools (our own callback),
        accept automatically — the user already opted in by enabling the
        runtime."""
        client = FakeClient()
        client.queue_server_request(
            "mcpServer/elicitation/request", request_id="elic-1",
            threadId="t", turnId="tu1",
            serverName="hermes-tools",
            mode="form",
            message="confirm",
            requestedSchema={"type": "object", "properties": {}},
        )
        client.queue_notification(
            "turn/completed", threadId="t",
            turn={"id": "tu1", "status": "completed", "error": None},
        )
        s = make_session(client)
        s.run_turn("hi", turn_timeout=1.0)
        assert ("elic-1", {"action": "accept", "content": None, "_meta": None}) in client.responses

    def test_mcp_elicitation_for_other_servers_declines(self):
        """For third-party MCP servers we decline by default so users
        explicitly opt in through codex's own UI."""
        client = FakeClient()
        client.queue_server_request(
            "mcpServer/elicitation/request", request_id="elic-2",
            threadId="t", turnId="tu1",
            serverName="some-third-party",
            mode="url",
            message="please log in",
            url="https://example.com/oauth",
        )
        client.queue_notification(
            "turn/completed", threadId="t",
            turn={"id": "tu1", "status": "completed", "error": None},
        )
        s = make_session(client)
        s.run_turn("hi", turn_timeout=1.0)
        assert ("elic-2", {"action": "decline", "content": None, "_meta": None}) in client.responses

    def test_routing_auto_approve_bypass(self):
        client = FakeClient()
        client.queue_server_request("item/commandExecution/requestApproval", request_id="r1",
                                    command="ls", cwd="/")
        client.queue_notification(
            "turn/completed", threadId="t",
            turn={"id": "tu1", "status": "completed", "error": None},
        )
        # No callback, but routing says auto-approve. Should approve.
        s = make_session(client, request_routing=_ServerRequestRouting(
            auto_approve_exec=True))
        s.run_turn("hi", turn_timeout=1.0)
        assert ("r1", {"decision": "accept"}) in client.responses

    def test_callback_raises_falls_back_to_decline(self):
        client = FakeClient()
        client.queue_server_request("item/commandExecution/requestApproval", request_id="r1",
                                    command="ls", cwd="/")
        client.queue_notification(
            "turn/completed", threadId="t",
            turn={"id": "tu1", "status": "completed", "error": None},
        )

        def boom(*a, **kw):
            raise RuntimeError("ui crashed")

        s = make_session(client, approval_callback=boom)
        s.run_turn("hi", turn_timeout=1.0)
        # Fail-closed: deny on callback exception
        assert ("r1", {"decision": "decline"}) in client.responses


# ---- enriched approval prompts ----

class TestApprovalPromptEnrichment:
    """Quirk #4: apply_patch prompt should show what's changing.
    Quirk #10: exec prompt should never show empty cwd."""

    def test_exec_falls_back_to_session_cwd(self):
        """When codex omits cwd from the approval params, the prompt shows
        the session cwd, not an empty string."""
        client = FakeClient()
        client.queue_server_request(
            "item/commandExecution/requestApproval", request_id="r1",
            command="ls",  # no cwd
        )
        client.queue_notification(
            "turn/completed", threadId="t",
            turn={"id": "tu1", "status": "completed", "error": None},
        )
        captured = {}
        def cb(command, description, *, allow_permanent=True):
            captured["description"] = description
            return "once"
        s = make_session(client, approval_callback=cb)
        s.run_turn("hi", turn_timeout=1.0)
        # Session cwd is /tmp by default in make_session()
        assert "/tmp" in captured["description"]
        assert "Codex requests exec in <unknown>" not in captured["description"]

    def test_apply_patch_prompt_summarizes_pending_changes(self):
        """When the projector has cached the fileChange item from item/started,
        the approval prompt surfaces the change summary."""
        client = FakeClient()
        # item/started fires first (carries the changes), then approval request
        client.queue_notification(
            "item/started",
            item={"type": "fileChange", "id": "fc-1",
                  "changes": [
                      {"kind": {"type": "add"}, "path": "/tmp/new.py"},
                      {"kind": {"type": "update"}, "path": "/tmp/old.py"},
                  ]},
            threadId="t", turnId="tu1",
        )
        client.queue_server_request(
            "item/fileChange/requestApproval", request_id="req-2",
            itemId="fc-1", turnId="tu1", threadId="t",
            startedAtMs=1234567890,
            reason="add and update files",
        )
        client.queue_notification(
            "turn/completed", threadId="t",
            turn={"id": "tu1", "status": "completed", "error": None},
        )
        captured = {}
        def cb(command, description, *, allow_permanent=True):
            captured["command"] = command
            captured["description"] = description
            return "once"
        s = make_session(client, approval_callback=cb)
        s.run_turn("hi", turn_timeout=1.0)
        # Both add and update kinds should be in the summary
        assert "1 add" in captured["command"] or "1 add" in captured["description"]
        assert "1 update" in captured["command"] or "1 update" in captured["description"]
        # And at least one of the paths
        joined = captured["command"] + " " + captured["description"]
        assert "/tmp/new.py" in joined or "/tmp/old.py" in joined

    def test_apply_patch_prompt_works_without_cached_summary(self):
        """When approval arrives before item/started (or without changes
        info), prompt falls back to whatever codex provided."""
        client = FakeClient()
        client.queue_server_request(
            "item/fileChange/requestApproval", request_id="req-2",
            itemId="fc-orphan", turnId="tu1", threadId="t",
            startedAtMs=1234567890,
            reason="apply some changes",
        )
        client.queue_notification(
            "turn/completed", threadId="t",
            turn={"id": "tu1", "status": "completed", "error": None},
        )
        captured = {}
        def cb(command, description, *, allow_permanent=True):
            captured["command"] = command
            return "once"
        s = make_session(client, approval_callback=cb)
        s.run_turn("hi", turn_timeout=1.0)
        # Falls back to the reason
        assert "apply some changes" in captured["command"]