package helps import (	"bytes" 	"github.com/tidwall/gjson"	"github.com/tidwall/sjson") // EnsureResponsesUsageDetails ensures that Responses usage objects contain output_tokens_details// (defaulting reasoning_tokens to 0) and input_tokens_details (defaulting cached_tokens to 0).// It supports plain JSON payloads, single-line SSE data: lines, and multi-line SSE frames (e.g. event: ...\ndata: ...).func EnsureResponsesUsageDetails(payload []byte) []byte {	if len(payload) == 0 {		return payload	} 	trimmed := bytes.TrimSpace(payload)	if len(trimmed) == 0 {		return payload	} 	// 1. JSON-first: If trimmed payload starts with '{', process as a plain JSON object.	if trimmed[0] == '{' {		if gjson.GetBytes(trimmed, "object").String() == "response.compaction" {			return payload		}		updated := trimmed		updated = ensureUsageDetailsAt(updated, "response.usage")		updated = ensureUsageDetailsAt(updated, "usage")		if bytes.Equal(updated, trimmed) {			return payload		}		return updated	} 	// 2. SSE frames: Scan lines for data: prefixed lines and patch their JSON payloads.	if bytes.Contains(payload, []byte("data:")) {		lines := bytes.Split(payload, []byte("\n"))		modified := false		for i, line := range lines {			trimmedLine := bytes.TrimSpace(line)			if !bytes.HasPrefix(trimmedLine, []byte("data:")) {				continue			}			prefixLen := len("data:")			if bytes.HasPrefix(line, []byte("data: ")) {				prefixLen = len("data: ")			} else if bytes.HasPrefix(line, []byte("data:")) {				prefixLen = len("data:")			}			dataPayload := bytes.TrimSpace(line[prefixLen:])			if len(dataPayload) == 0 || dataPayload[0] != '{' {				continue			}			if gjson.GetBytes(dataPayload, "object").String() == "response.compaction" {				continue			}			updated := dataPayload			updated = ensureUsageDetailsAt(updated, "response.usage")			updated = ensureUsageDetailsAt(updated, "usage")			if !bytes.Equal(updated, dataPayload) {				newPrefix := bytes.Clone(line[:prefixLen])				lines[i] = append(newPrefix, updated...)				modified = true			}		}		if modified {			return bytes.Join(lines, []byte("\n"))		}		return payload	} 	return payload} func ensureUsageDetailsAt(jsonBody []byte, path string) []byte {	usageNode := gjson.GetBytes(jsonBody, path)	if !usageNode.Exists() || !usageNode.IsObject() {		return jsonBody	} 	outputDetails := usageNode.Get("output_tokens_details")	if !outputDetails.Exists() {		jsonBody, _ = sjson.SetBytes(jsonBody, path+".output_tokens_details.reasoning_tokens", 0)	} else if outputDetails.Type == gjson.Null || !outputDetails.IsObject() {		jsonBody, _ = sjson.SetRawBytes(jsonBody, path+".output_tokens_details", []byte(`{"reasoning_tokens":0}`))	} else {		reasoning := outputDetails.Get("reasoning_tokens")		if !reasoning.Exists() || reasoning.Type == gjson.Null {			jsonBody, _ = sjson.SetBytes(jsonBody, path+".output_tokens_details.reasoning_tokens", 0)		}	} 	inputDetails := usageNode.Get("input_tokens_details")	if !inputDetails.Exists() {		jsonBody, _ = sjson.SetBytes(jsonBody, path+".input_tokens_details.cached_tokens", 0)	} else if inputDetails.Type == gjson.Null || !inputDetails.IsObject() {		jsonBody, _ = sjson.SetRawBytes(jsonBody, path+".input_tokens_details", []byte(`{"cached_tokens":0}`))	} else {		cached := inputDetails.Get("cached_tokens")		if !cached.Exists() || cached.Type == gjson.Null {			jsonBody, _ = sjson.SetBytes(jsonBody, path+".input_tokens_details.cached_tokens", 0)		}	} 	return jsonBody}