package executor

import (
	"bytes"
	"context"
	"fmt"
	"io"
	"net/http"
	"strings"
	"testing"

	"github.com/google/uuid"
	claudeauth "github.com/router-for-me/CLIProxyAPI/v7/internal/auth/claude"
	"github.com/router-for-me/CLIProxyAPI/v7/internal/config"
	cliproxyauth "github.com/router-for-me/CLIProxyAPI/v7/sdk/cliproxy/auth"
	cliproxyexecutor "github.com/router-for-me/CLIProxyAPI/v7/sdk/cliproxy/executor"
	sdktranslator "github.com/router-for-me/CLIProxyAPI/v7/sdk/translator"
	"github.com/tidwall/gjson"
)

func TestInjectClaudeDiagnosticsMatchesNativeFieldOrderAndContinuity(t *testing.T) {
	t.Parallel()

	body := []byte(`{"context_management":{"edits":[{"type":"clear_thinking_20251015","keep":"all"}]},"max_tokens":1,"messages":[]}`)
	testID := uuid.NewString()
	auth := &cliproxyauth.Auth{ID: "credential-diagnostics-order-" + testID}
	first, state := injectClaudeDiagnostics(body, auth, "session-diagnostics-order-"+testID)
	wantOrder := `"context_management":{"edits":[{"type":"clear_thinking_20251015","keep":"all"}]},"diagnostics":{"previous_message_id":null},"max_tokens"`
	if !bytes.Contains(first, []byte(wantOrder)) {
		t.Fatalf("diagnostics field order differs from native: %s", first)
	}
	if got := gjson.GetBytes(first, "diagnostics.previous_message_id"); got.Type != gjson.Null {
		t.Fatalf("first previous_message_id = %s, want null", got.Raw)
	}

	commitClaudeDiagnostics(state, "msg_01ABCDEF0123456789ABCDEFG")
	second, _ := injectClaudeDiagnostics(body, auth, "session-diagnostics-order-"+testID)
	if got := gjson.GetBytes(second, "diagnostics.previous_message_id").String(); got != "msg_01ABCDEF0123456789ABCDEFG" {
		t.Fatalf("second previous_message_id = %q, want committed upstream ID", got)
	}
}

func TestClaudeExecutorDiagnosticsAdvancesAfterSuccessfulResponse(t *testing.T) {
	var previousValues []gjson.Result
	var betaValues []string
	call := 0
	transport := roundTripperFunc(func(req *http.Request) (*http.Response, error) {
		body, errRead := io.ReadAll(req.Body)
		if errRead != nil {
			t.Fatal(errRead)
		}
		previousValues = append(previousValues, gjson.GetBytes(body, "diagnostics.previous_message_id"))
		betas := req.Header.Get("Anthropic-Beta")
		if betas == "" {
			betas = strings.Join(req.Header["anthropic-beta"], ",")
		}
		betaValues = append(betaValues, betas)
		call++
		response := `{"id":"msg_diagnostics_` + string(rune('0'+call)) + `","type":"message","model":"claude-opus-5","role":"assistant","content":[{"type":"text","text":"ok"}],"usage":{"input_tokens":1,"output_tokens":1}}`
		return &http.Response{StatusCode: http.StatusOK, Header: http.Header{"Content-Type": []string{"application/json"}}, Body: io.NopCloser(strings.NewReader(response)), Request: req}, nil
	})
	ctx := context.WithValue(context.Background(), "cliproxy.roundtripper", http.RoundTripper(transport))
	deviceIDs := []string{"0000000000000000000000000000000000000000000000000000000000000000"}
	testID := uuid.NewString()
	auth := &cliproxyauth.Auth{
		ID:         "diagnostics-live-path-" + testID,
		Attributes: map[string]string{"api_key": "sk-ant-oat-diagnostics-live-path"},
		Metadata: map[string]any{
			"account_uuid":                        "aaaaaaaa-aaaa-4aaa-8aaa-aaaaaaaaaaaa",
			claudeauth.ClaudeDeviceIDsMetadataKey: deviceIDs,
		},
	}
	executor := NewClaudeExecutor(&config.Config{})
	request := cliproxyexecutor.Request{Model: "claude-opus-5", Payload: []byte(`{"model":"claude-opus-5","messages":[{"role":"user","content":"x"}],"max_tokens":16}`)}
	options := cliproxyexecutor.Options{
		SourceFormat: sdktranslator.FormatClaude,
		Metadata:     map[string]any{cliproxyexecutor.ExecutionSessionMetadataKey: "diagnostics-conversation-" + testID},
	}
	for turn := range 2 {
		if _, errExecute := executor.Execute(ctx, auth, request, options); errExecute != nil {
			t.Fatalf("Execute() error = %v", errExecute)
		}
		if turn == 0 {
			auth.Attributes["api_key"] = "sk-ant-oat-diagnostics-live-path-rotated"
		}
	}
	if len(previousValues) != 2 || previousValues[0].Type != gjson.Null || previousValues[0].Raw != "null" {
		t.Fatalf("first diagnostics value = %#v, want explicit null", previousValues)
	}
	if got := previousValues[1].String(); got != "msg_diagnostics_1" {
		t.Fatalf("second diagnostics previous_message_id = %q, want first upstream response ID", got)
	}
	wantTrailer := claudeExtendedCacheTTLBeta + "," + claudeCacheDiagnosisBeta
	for turn, betas := range betaValues {
		if !strings.HasSuffix(betas, wantTrailer) {
			t.Fatalf("turn %d Anthropic-Beta = %q, want native diagnostics trailer %q", turn+1, betas, wantTrailer)
		}
	}
}

func TestClaudeMessageIDFromSSECommitsOnlyCompletedMessage(t *testing.T) {
	t.Parallel()

	complete := []byte("event: message_start\ndata: {\"type\":\"message_start\",\"message\":{\"id\":\"msg_complete\"}}\n\nevent: message_stop\ndata: {\"type\":\"message_stop\"}\n\n")
	if got := claudeMessageIDFromSSE(complete); got != "msg_complete" {
		t.Fatalf("completed SSE message ID = %q, want msg_complete", got)
	}
	incomplete := []byte(strings.Replace(string(complete), "event: message_stop\ndata: {\"type\":\"message_stop\"}\n\n", "", 1))
	if got := claudeMessageIDFromSSE(incomplete); got != "" {
		t.Fatalf("incomplete SSE message ID = %q, want empty", got)
	}
}

func TestClaudeExecutorContinuityAdvancesRequestIDAndPromptIDInBillingHeader(t *testing.T) {
	var capturedBillingHeaders []string
	call := 0
	transport := roundTripperFunc(func(req *http.Request) (*http.Response, error) {
		body, errRead := io.ReadAll(req.Body)
		if errRead != nil {
			t.Fatal(errRead)
		}
		billing := gjson.GetBytes(body, "system.0.text").String()
		capturedBillingHeaders = append(capturedBillingHeaders, billing)
		call++
		response := `{"id":"msg_turn_` + string(rune('0'+call)) + `","type":"message","model":"claude-sonnet-5","role":"assistant","content":[{"type":"text","text":"ok"}],"usage":{"input_tokens":1,"output_tokens":1}}`
		header := http.Header{
			"Content-Type": []string{"application/json"},
			"request-id":   []string{fmt.Sprintf("req_upstream_turn_%d", call)},
		}
		return &http.Response{StatusCode: http.StatusOK, Header: header, Body: io.NopCloser(strings.NewReader(response)), Request: req}, nil
	})
	ctx := context.WithValue(context.Background(), "cliproxy.roundtripper", http.RoundTripper(transport))
	deviceIDs := []string{"0000000000000000000000000000000000000000000000000000000000000000"}
	testID := uuid.NewString()
	auth := &cliproxyauth.Auth{
		ID:         "continuity-test-" + testID,
		Attributes: map[string]string{"api_key": "sk-ant-oat-continuity-test"},
		Metadata: map[string]any{
			"account_uuid":                        "aaaaaaaa-aaaa-4aaa-8aaa-aaaaaaaaaaaa",
			claudeauth.ClaudeDeviceIDsMetadataKey: deviceIDs,
		},
	}
	executor := NewClaudeExecutor(&config.Config{})
	options := cliproxyexecutor.Options{
		SourceFormat: sdktranslator.FormatClaude,
		Metadata:     map[string]any{cliproxyexecutor.ExecutionSessionMetadataKey: "continuity-conv-" + testID},
	}

	// Turn 1: User prompt
	req1 := cliproxyexecutor.Request{Model: "claude-sonnet-5", Payload: []byte(`{"model":"claude-sonnet-5","messages":[{"role":"user","content":"turn 1 prompt"}],"max_tokens":100}`)}
	if _, err := executor.Execute(ctx, auth, req1, options); err != nil {
		t.Fatalf("turn 1 failed: %v", err)
	}

	// Turn 2: User prompt in same conversation
	req2 := cliproxyexecutor.Request{Model: "claude-sonnet-5", Payload: []byte(`{"model":"claude-sonnet-5","messages":[{"role":"user","content":"turn 1 prompt"},{"role":"assistant","content":"ok"},{"role":"user","content":"turn 2 prompt"}],"max_tokens":100}`)}
	if _, err := executor.Execute(ctx, auth, req2, options); err != nil {
		t.Fatalf("turn 2 failed: %v", err)
	}

	// Turn 2.1: Tool result continuation within turn 2
	req2Tool := cliproxyexecutor.Request{Model: "claude-sonnet-5", Payload: []byte(`{"model":"claude-sonnet-5","messages":[{"role":"user","content":"turn 1 prompt"},{"role":"assistant","content":"ok"},{"role":"user","content":"turn 2 prompt"},{"role":"assistant","content":[{"type":"tool_use","id":"t1","name":"bash","input":{}}]},{"role":"user","content":[{"type":"tool_result","tool_use_id":"t1","content":"tool output"}]}],"max_tokens":100}`)}
	if _, err := executor.Execute(ctx, auth, req2Tool, options); err != nil {
		t.Fatalf("turn 2.1 tool failed: %v", err)
	}

	// Turn 3: Probe request (max_tokens: 1)
	reqProbe := cliproxyexecutor.Request{Model: "claude-sonnet-5", Payload: []byte(`{"model":"claude-sonnet-5","messages":[{"role":"user","content":"probe"}],"max_tokens":1}`)}
	if _, err := executor.Execute(ctx, auth, reqProbe, options); err != nil {
		t.Fatalf("probe failed: %v", err)
	}

	// Turn 4: Subagent request (carrying X-Claude-Code-Agent-Id)
	subagentOptions := cliproxyexecutor.Options{
		SourceFormat: sdktranslator.FormatClaude,
		Headers:      http.Header{"X-Claude-Code-Agent-Id": []string{"subagent-worker-1"}},
		Metadata:     map[string]any{cliproxyexecutor.ExecutionSessionMetadataKey: "continuity-subagent-" + testID},
	}
	reqSubagent := cliproxyexecutor.Request{Model: "claude-sonnet-5", Payload: []byte(`{"model":"claude-sonnet-5","messages":[{"role":"user","content":"subagent prompt"}],"max_tokens":100}`)}
	if _, err := executor.Execute(ctx, auth, reqSubagent, subagentOptions); err != nil {
		t.Fatalf("subagent failed: %v", err)
	}

	// Turn 5: Resumed main session user prompt after probe (must chain from turn 2.1, NOT from probe turn 3)
	req5 := cliproxyexecutor.Request{Model: "claude-sonnet-5", Payload: []byte(`{"model":"claude-sonnet-5","messages":[{"role":"user","content":"turn 5 prompt"}],"max_tokens":100}`)}
	if _, err := executor.Execute(ctx, auth, req5, options); err != nil {
		t.Fatalf("turn 5 failed: %v", err)
	}

	if len(capturedBillingHeaders) != 6 {
		t.Fatalf("captured %d billing headers, want 6", len(capturedBillingHeaders))
	}

	// Verify Turn 1:
	h1 := capturedBillingHeaders[0]
	if !strings.Contains(h1, "cc_version=2.1.258.") || !strings.Contains(h1, "cc_entrypoint=cli;") || !strings.Contains(h1, "cch=") {
		t.Fatalf("h1 invalid: %s", h1)
	}
	if strings.Contains(h1, "cc_prev_req=") {
		t.Fatalf("h1 must not contain cc_prev_req: %s", h1)
	}
	if !strings.Contains(h1, "cc_prompt_id=") {
		t.Fatalf("h1 must contain cc_prompt_id: %s", h1)
	}
	prompt1 := extractTag(h1, "cc_prompt_id=")

	// Verify Turn 2:
	h2 := capturedBillingHeaders[1]
	if !strings.Contains(h2, "cc_prev_req=req_upstream_turn_1;") {
		t.Fatalf("h2 must contain cc_prev_req=req_upstream_turn_1;, got: %s", h2)
	}
	if !strings.Contains(h2, "cc_prompt_id=") {
		t.Fatalf("h2 must contain cc_prompt_id: %s", h2)
	}
	prompt2 := extractTag(h2, "cc_prompt_id=")
	if prompt2 == prompt1 {
		t.Fatalf("h2 promptID (%s) must differ from h1 promptID (%s)", prompt2, prompt1)
	}

	// Verify Turn 2.1 (tool continuation):
	h2Tool := capturedBillingHeaders[2]
	if !strings.Contains(h2Tool, "cc_prev_req=req_upstream_turn_2;") {
		t.Fatalf("h2Tool must contain cc_prev_req=req_upstream_turn_2;, got: %s", h2Tool)
	}
	prompt2Tool := extractTag(h2Tool, "cc_prompt_id=")
	if prompt2Tool != prompt2 {
		t.Fatalf("h2Tool promptID (%s) must match turn 2 promptID (%s)", prompt2Tool, prompt2)
	}

	// Verify Turn 3 (probe with max_tokens: 1):
	hProbe := capturedBillingHeaders[3]
	if strings.Contains(hProbe, "cc_prev_req=") || strings.Contains(hProbe, "cc_prompt_id=") {
		t.Fatalf("probe must not contain cc_prev_req or cc_prompt_id: %s", hProbe)
	}

	// Verify Turn 4 (subagent):
	hSubagent := capturedBillingHeaders[4]
	if !strings.Contains(hSubagent, "cc_is_subagent=true;") {
		t.Fatalf("hSubagent must contain cc_is_subagent=true;, got: %s", hSubagent)
	}
	if !strings.Contains(hSubagent, "cc_prompt_id=") {
		t.Fatalf("hSubagent must contain cc_prompt_id: %s", hSubagent)
	}

	// Verify Turn 5 (main turn after probe):
	// Must chain to turn 2.1's response (req_upstream_turn_3), bypassing probe turn 3 (req_upstream_turn_4)!
	h5 := capturedBillingHeaders[5]
	if !strings.Contains(h5, "cc_prev_req=req_upstream_turn_3;") {
		t.Fatalf("h5 must contain cc_prev_req=req_upstream_turn_3; (bypassing probe turn 4), got: %s", h5)
	}
	if !strings.Contains(h5, "cc_prompt_id=") {
		t.Fatalf("h5 must contain cc_prompt_id: %s", h5)
	}
}

func extractTag(header, prefix string) string {
	idx := strings.Index(header, prefix)
	if idx < 0 {
		return ""
	}
	val := header[idx+len(prefix):]
	if end := strings.IndexByte(val, ';'); end >= 0 {
		val = val[:end]
	}
	return val
}