package service

import (
	"context"
	"net/http"
	"testing"

	"github.com/Wei-Shaw/sub2api/internal/pkg/apicompat"
	"github.com/stretchr/testify/require"
	"github.com/tidwall/gjson"
)

// codexNamespaceRequestBody 模拟 Codex 多智能体请求：collaboration 命名空间声明 +
// 历史里的命名空间调用项 + 带残留 namespace 的普通消息项。
const codexNamespaceRequestBody = `{
	"model":"gpt-5.6-terra",
	"stream":false,
	"instructions":"test",
	"tools":[
		{"type":"namespace","name":"collaboration","description":"Tools for spawning and managing sub-agents.","tools":[
			{"type":"function","name":"spawn_agent","description":"Call as to=functions.collaboration.spawn_agent","parameters":{"type":"object"}},
			{"type":"function","name":"wait_agent","parameters":{"type":"object"}}
		]},
		{"type":"function","name":"exec","parameters":{"type":"object"}}
	],
	"input":[
		{"type":"function_call","namespace":"collaboration","name":"spawn_agent","call_id":"call_1","arguments":"{}"},
		{"type":"message","role":"user","namespace":"leftover","content":[{"type":"input_text","text":"hello"}]}
	]
}`

const namespaceForwardOKResponse = `{"id":"resp_ns","output":[],"usage":{"input_tokens":1,"output_tokens":1,"input_tokens_details":{"cached_tokens":0}}}`

// OAuth 出口即 namespace 扩展的定义方：声明必须原样送达，历史调用项必须保留
// namespace（缺字段上游会 400 "Missing namespace for function_call"），而非调用项上的
// 残留 namespace 仍要清掉。回归 issue #4978。
func TestOpenAIGatewayService_OAuthPreservesCodexNamespaceTools(t *testing.T) {
	body := []byte(codexNamespaceRequestBody)
	upstream := &httpUpstreamRecorder{responses: []*http.Response{
		newOpenAIRejectedFieldTestResponse(http.StatusOK, namespaceForwardOKResponse),
	}}
	c := newOpenAIRejectedFieldTestContext(body)

	result, err := newOpenAIRejectedFieldTestService(upstream).Forward(
		context.Background(), c, newOpenAIOAuthNamespaceTestAccount(), body,
	)

	require.NoError(t, err)
	require.NotNil(t, result)
	require.Len(t, upstream.bodies, 1)
	forwarded := upstream.bodies[0]

	namespaceTool := gjson.GetBytes(forwarded, `tools.#(type=="namespace")`)
	require.True(t, namespaceTool.Exists(), "namespace 声明必须原样转发")
	require.Equal(t, "collaboration", namespaceTool.Get("name").String())
	require.Equal(t, "spawn_agent", namespaceTool.Get("tools.0.name").String())
	require.Equal(t, "wait_agent", namespaceTool.Get("tools.1.name").String())
	// 摊平名一旦出现，模型就无法按工具描述里的 to=functions.collaboration.spawn_agent 寻址。
	require.NotContains(t, string(forwarded), "collaboration__spawn_agent")

	require.Equal(t, "collaboration", gjson.GetBytes(forwarded, "input.0.namespace").String())
	require.Equal(t, "spawn_agent", gjson.GetBytes(forwarded, "input.0.name").String())
	require.False(t, gjson.GetBytes(forwarded, "input.1.namespace").Exists())

	// 未摊平即无需回程还原，不得登记映射。
	require.Empty(t, openAIResponsesNamespaceNames(c))
}

// compact 端点 schema 更窄：input[].namespace 会 400 Unknown parameter（issue #4761），
// 且没有证据表明它接受 namespace 工具声明。compact 只做历史摘要、不需要模型寻址工具，
// 因此保持既有的摊平 + 全量清理行为，不随默认值翻转扩大风险面。
func TestOpenAIGatewayService_OAuthCompactKeepsFlattening(t *testing.T) {
	body := []byte(codexNamespaceRequestBody)
	upstream := &httpUpstreamRecorder{responses: []*http.Response{
		newOpenAIRejectedFieldTestResponse(http.StatusOK, namespaceForwardOKResponse),
	}}
	c := newOpenAIRejectedFieldTestContext(body)
	c.Request.URL.Path = "/v1/responses/compact"

	result, err := newOpenAIRejectedFieldTestService(upstream).Forward(
		context.Background(), c, newOpenAIOAuthNamespaceTestAccount(), body,
	)

	require.NoError(t, err)
	require.NotNil(t, result)
	require.Len(t, upstream.bodies, 1)
	forwarded := upstream.bodies[0]

	require.False(t, gjson.GetBytes(forwarded, "input.0.namespace").Exists())
	require.False(t, gjson.GetBytes(forwarded, "input.1.namespace").Exists())
	require.False(t, gjson.GetBytes(forwarded, `tools.#(type=="namespace")`).Exists())
	require.Equal(t, "collaboration__spawn_agent", gjson.GetBytes(forwarded, "input.0.name").String())
}

// 账号开关为不认识 namespace 的兼容上游保留退路：打开后恢复 0.1.166 的摊平行为。
func TestOpenAIGatewayService_OAuthFlattenFlagRestoresLegacyBehavior(t *testing.T) {
	body := []byte(codexNamespaceRequestBody)
	upstream := &httpUpstreamRecorder{responses: []*http.Response{
		newOpenAIRejectedFieldTestResponse(http.StatusOK, namespaceForwardOKResponse),
	}}
	c := newOpenAIRejectedFieldTestContext(body)
	account := newOpenAIOAuthNamespaceTestAccount()
	account.Extra = map[string]any{"openai_responses_flatten_namespaces": true}

	result, err := newOpenAIRejectedFieldTestService(upstream).Forward(
		context.Background(), c, account, body,
	)

	require.NoError(t, err)
	require.NotNil(t, result)
	require.Len(t, upstream.bodies, 1)
	forwarded := upstream.bodies[0]

	require.False(t, gjson.GetBytes(forwarded, `tools.#(type=="namespace")`).Exists())
	require.True(t, gjson.GetBytes(forwarded, `tools.#(name=="collaboration__spawn_agent")`).Exists())
	require.True(t, gjson.GetBytes(forwarded, `tools.#(name=="collaboration__wait_agent")`).Exists())
	// 摊平后调用项已改写成平名，不得再带 namespace。
	require.Equal(t, "collaboration__spawn_agent", gjson.GetBytes(forwarded, "input.0.name").String())
	require.False(t, gjson.GetBytes(forwarded, "input.0.namespace").Exists())
	require.False(t, gjson.GetBytes(forwarded, "input.1.namespace").Exists())

	names := openAIResponsesNamespaceNames(c)
	require.Equal(t,
		apicompat.ResponsesNamespaceName{Namespace: "collaboration", Name: "spawn_agent"},
		names["collaboration__spawn_agent"],
	)
}

// handler 的 failover 在同一个 *gin.Context 上重试下一个账号；保留 namespace 的账号
// 不得沿用上一个账号登记的摊平名映射做回程还原。
func TestOpenAIGatewayService_ForwardClearsStaleNamespaceNames(t *testing.T) {
	body := []byte(codexNamespaceRequestBody)
	upstream := &httpUpstreamRecorder{responses: []*http.Response{
		newOpenAIRejectedFieldTestResponse(http.StatusOK, namespaceForwardOKResponse),
	}}
	c := newOpenAIRejectedFieldTestContext(body)
	setOpenAIResponsesNamespaceNames(c, map[string]apicompat.ResponsesNamespaceName{
		"stale__tool": {Namespace: "stale", Name: "tool"},
	})

	_, err := newOpenAIRejectedFieldTestService(upstream).Forward(
		context.Background(), c, newOpenAIOAuthNamespaceTestAccount(), body,
	)

	require.NoError(t, err)
	require.Empty(t, openAIResponsesNamespaceNames(c))
}