package loop

import (
	"context"
	"testing"

	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/agent"
	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/model"
)

// nativeDatetimeCall is a provider-native tool call response: the adapters put
// the call in Response.ToolCalls (not in Content), which is exactly the shape a
// thinking model returns for "what time is it" when the datetime tool is
// advertised. Content is empty, so a loop that ignores ToolCalls produces a
// silent empty reply.
func nativeDatetimeCall() model.Response {
	return model.Response{
		Model:   "m",
		Content: "",
		ToolCalls: []model.ToolCall{{
			ID:   "call_native_1",
			Name: "datetime",
			Args: map[string]any{"timezone": "Asia/Shanghai"},
		}},
	}
}

// assertNativeFeedBack checks that req carries the assistant tool_use turn and a
// correlated tool result for toolCallID.
func assertNativeFeedBack(t *testing.T, req model.Request, toolCallID string) {
	t.Helper()
	for i := 0; i < len(req.Messages)-1; i++ {
		m := req.Messages[i]
		if m.Role != model.RoleAssistant || len(m.Content) == 0 {
			continue
		}
		if m.Content[0].Type != model.ContentTypeToolCall || m.Content[0].ToolCallID != toolCallID {
			continue
		}
		next := req.Messages[i+1]
		if next.Role != model.RoleTool {
			t.Fatalf("message after assistant tool_use has role %q, want tool", next.Role)
		}
		if next.ToolCallID != toolCallID {
			t.Fatalf("tool result ToolCallID = %q, want %q", next.ToolCallID, toolCallID)
		}
		if len(next.Content) == 0 || next.Content[0].Type != model.ContentTypeToolResult {
			t.Fatalf("tool result content = %+v, want a tool_result part", next.Content)
		}
		return
	}
	t.Fatalf("no native assistant tool_use + tool_result pair for %q in %+v", toolCallID, req.Messages)
}

// TestRun_NativeToolCall_Streaming covers the real chat path (the loop drives
// ChatStream when OnStream is set): a native provider tool call with empty
// Content must be executed and fed back as native tool_use + tool_result, and
// the run must finish with the model's follow-up text instead of an empty reply.
func TestRun_NativeToolCall_Streaming(t *testing.T) {
	t.Parallel()
	ad := &mockAdapter{stream: []mgResp{
		{resp: nativeDatetimeCall()},
		{resp: model.Response{Model: "m", Content: "现在是 10:34。"}},
	}}
	td := dispatcherWith(t, &mockTool{name: "datetime", result: map[string]any{"now": "2026-09-08 22:34:00"}})
	a := newTestAgent(t, ad, td)
	l := New(Options{Agent: a, MaxRounds: 8, OnStream: func(model.StreamEvent) {}})

	res, err := l.Run(context.Background(), "sess", []model.Message{model.TextMessage(model.RoleUser, "瞅瞅当前系统时间是多少")})
	if err != nil {
		t.Fatalf("Run: %v", err)
	}
	if res.Text != "现在是 10:34。" {
		t.Fatalf("Text = %q, want the follow-up answer (empty means the native call was dropped)", res.Text)
	}
	if res.Steps != 2 {
		t.Fatalf("Steps = %d, want 2", res.Steps)
	}
	if res.ToolCallsExecuted != 1 {
		t.Fatalf("ToolCallsExecuted = %d, want 1", res.ToolCallsExecuted)
	}
	if len(ad.streamReqs) < 2 {
		t.Fatalf("stream requests = %d, want >= 2", len(ad.streamReqs))
	}
	assertNativeFeedBack(t, ad.streamReqs[1], "call_native_1")
}

// TestRun_NativeToolCall_NonStreaming covers the muted/internal path where the
// loop delegates to agent.RunStep (adapter.Chat), which must decode the same
// native tool call.
func TestRun_NativeToolCall_NonStreaming(t *testing.T) {
	t.Parallel()
	ad := &mockAdapter{chat: []mgResp{
		{resp: nativeDatetimeCall()},
		{resp: model.Response{Model: "m", Content: "现在是 10:34。"}},
	}}
	td := dispatcherWith(t, &mockTool{name: "datetime", result: map[string]any{"now": "2026-09-08 22:34:00"}})
	a := newTestAgent(t, ad, td)
	l := New(Options{Agent: a, MaxRounds: 8})

	res, err := l.Run(context.Background(), "sess", []model.Message{model.TextMessage(model.RoleUser, "几点了")})
	if err != nil {
		t.Fatalf("Run: %v", err)
	}
	if res.Text != "现在是 10:34。" || res.ToolCallsExecuted != 1 {
		t.Fatalf("Text = %q, ToolCallsExecuted = %d; want follow-up text + 1 call", res.Text, res.ToolCallsExecuted)
	}
	if len(ad.reqs) < 2 {
		t.Fatalf("chat requests = %d, want >= 2", len(ad.reqs))
	}
	assertNativeFeedBack(t, ad.reqs[1], "call_native_1")
}

// TestExtractToolCalls_PrefersNative pins the decoder contract: provider-native
// ToolCalls win over a Content envelope and preserve the provider id, so the
// feed-back can correlate the result.
func TestExtractToolCalls_PrefersNative(t *testing.T) {
	t.Parallel()
	resp := nativeDatetimeCall()
	resp.Content = `{"tool_calls":[{"name":"legacy","args":{}}]}`
	calls, ok := agent.ExtractToolCalls(resp)
	if !ok || len(calls) != 1 {
		t.Fatalf("ExtractToolCalls = (%+v, %v), want 1 native call", calls, ok)
	}
	if calls[0].ID != "call_native_1" || calls[0].Name != "datetime" {
		t.Fatalf("native call = %+v, want id=call_native_1 name=datetime", calls[0])
	}
	if calls[0].Args["timezone"] != "Asia/Shanghai" {
		t.Fatalf("native args = %+v, want timezone=Asia/Shanghai", calls[0].Args)
	}
}