ChatCompletionSystemMessageParam,

ChatCompletionToolMessageParam,

} from "openai/resources/chat/completions.js";

import {

splitSystemPromptCacheBoundary,

stripSystemPromptCacheBoundary,

} from "../../agents/system-prompt-cache-boundary.js";

import { createReasoningTagTextPartitioner } from "../../shared/text/reasoning-tag-text-partitioner.js";

import { getEnvApiKey } from "../env-api-keys.js";

import { calculateCost, clampThinkingLevel } from "../model-utils.js";

compat: ResolvedOpenAICompletionsCompat = getCompat(model),

cacheRetention: CacheRetention = resolveCacheRetention(options?.cacheRetention),

) {

const messages = convertMessages(model, context, compat);

const cacheControl = getCompatCacheControl(compat, cacheRetention);

const messages = convertMessages(model, context, compat, {

preserveSystemPromptCacheBoundary: cacheControl !== undefined,

});

type ChatCompletionRequestParams = Omit<

OpenAI.Chat.Completions.ChatCompletionCreateParamsStreaming,

if (content.length === 0) {

return false;

}

message.content = [

{

type: "text",

text: content,

cache_control: cacheControl,

},

] as ChatCompletionTextPartWithCacheControl[];

message.content = buildCacheControlledTextParts(content, cacheControl);

return true;

}

for (let i = content.length - 1; i >= 0; i--) {

const part = content[i];

if (part?.type === "text") {

const textPart = part as ChatCompletionTextPartWithCacheControl;

textPart.cache_control = cacheControl;

const text = (part as ChatCompletionTextPartWithCacheControl).text;

content.splice(i, 1, ...buildCacheControlledTextParts(text, cacheControl));

return true;

}

}

return false;

}

function buildCacheControlledTextParts(

text: string,

cacheControl: OpenAICompatCacheControl,

): ChatCompletionTextPartWithCacheControl[] {

const split = splitSystemPromptCacheBoundary(text);

if (!split) {

return [{ type: "text", text, cache_control: cacheControl }];

}

const parts: ChatCompletionTextPartWithCacheControl[] = [];

if (split.stablePrefix) {

parts.push({

type: "text",

text: split.stablePrefix,

cache_control: cacheControl,

});

}

if (split.dynamicSuffix) {

parts.push({ type: "text", text: split.dynamicSuffix });

}

return parts.length > 0 ? parts : [{ type: "text", text: "" }];

}

export function convertMessages(

model: Model<"openai-completions">,

context: Context,

compat: ResolvedOpenAICompletionsCompat,

options: { preserveSystemPromptCacheBoundary?: boolean } = {},

): ChatCompletionMessageParam[] {

const params: ChatCompletionMessageParam[] = [];

if (context.systemPrompt) {

const useDeveloperRole = model.reasoning && compat.supportsDeveloperRole;

const role = useDeveloperRole ? "developer" : "system";

params.push({ role, content: sanitizeSurrogates(context.systemPrompt) });

const systemPrompt = options.preserveSystemPromptCacheBoundary

? context.systemPrompt

: stripSystemPromptCacheBoundary(context.systemPrompt);

params.push({

role,

content: sanitizeSurrogates(systemPrompt),

});

}

let lastRole: string | null = null;