{"version":3,"file":"estimate.d.ts","sourceRoot":"","sources":["../../src/utils/estimate.ts"],"names":[],"mappings":"AAAA,OAAO,KAAK,EAAoB,OAAO,EAAE,YAAY,EAAE,OAAO,EAAE,WAAW,EAAQ,KAAK,EAAE,MAAM,aAAa,CAAC;AAE9G,MAAM,WAAW,oBAAoB;IACpC,sCAAsC;IACtC,MAAM,EAAE,MAAM,CAAC;IACf,2EAA2E;IAC3E,WAAW,EAAE,MAAM,CAAC;IACpB,+EAA+E;IAC/E,cAAc,EAAE,MAAM,CAAC;IACvB,qFAAqF;IACrF,cAAc,EAAE,MAAM,GAAG,IAAI,CAAC;CAC9B;AAKD,wBAAgB,sBAAsB,CAAC,KAAK,EAAE,KAAK,GAAG,MAAM,CAE3D;AAkBD,wBAAgB,kBAAkB,CAAC,IAAI,EAAE,MAAM,GAAG,MAAM,CAEvD;AAED,wBAAgB,iCAAiC,CAAC,OAAO,EAAE,MAAM,GAAG,KAAK,CAAC,WAAW,GAAG,YAAY,CAAC,GAAG,MAAM,CAE7G;AAED,wBAAgB,qBAAqB,CAAC,OAAO,EAAE,OAAO,GAAG,MAAM,CAgB9D;AAqDD,wBAAgB,qBAAqB,CAAC,OAAO,EAAE,OAAO,GAAG,SAAS,OAAO,EAAE,GAAG,oBAAoB,CA6BjG","sourcesContent":["import type { AssistantMessage, Context, ImageContent, Message, TextContent, Tool, Usage } from \"../types.ts\";\n\nexport interface ContextUsageEstimate {\n\t/** Estimated total context tokens. */\n\ttokens: number;\n\t/** Tokens reported by the most recent applicable assistant usage block. */\n\tusageTokens: number;\n\t/** Estimated tokens after the most recent applicable assistant usage block. */\n\ttrailingTokens: number;\n\t/** Index of the applicable message that provided usage, or null when none exists. */\n\tlastUsageIndex: number | null;\n}\n\nconst CHARS_PER_TOKEN = 4;\nconst ESTIMATED_IMAGE_CHARS = 4800;\n\nexport function calculateContextTokens(usage: Usage): number {\n\treturn usage.totalTokens || usage.input + usage.output + usage.cacheRead + usage.cacheWrite;\n}\n\nfunction safeJsonStringify(value: unknown): string {\n\ttry {\n\t\treturn JSON.stringify(value) ?? \"undefined\";\n\t} catch {\n\t\treturn \"[unserializable]\";\n\t}\n}\n\nfunction estimateTextAndImageContentChars(content: string | Array<TextContent | ImageContent>): number {\n\tif (typeof content === \"string\") return content.length;\n\n\tlet chars = 0;\n\tfor (const block of content) chars += block.type === \"text\" ? block.text.length : ESTIMATED_IMAGE_CHARS;\n\treturn chars;\n}\n\nexport function estimateTextTokens(text: string): number {\n\treturn Math.ceil(text.length / CHARS_PER_TOKEN);\n}\n\nexport function estimateTextAndImageContentTokens(content: string | Array<TextContent | ImageContent>): number {\n\treturn Math.ceil(estimateTextAndImageContentChars(content) / CHARS_PER_TOKEN);\n}\n\nexport function estimateMessageTokens(message: Message): number {\n\tlet chars = 0;\n\n\tif (message.role === \"user\") return estimateTextAndImageContentTokens(message.content);\n\tif (message.role === \"toolResult\") return estimateTextAndImageContentTokens(message.content);\n\n\tfor (const block of message.content) {\n\t\tif (block.type === \"text\") {\n\t\t\tchars += block.text.length;\n\t\t} else if (block.type === \"thinking\") {\n\t\t\tchars += block.thinking.length;\n\t\t} else {\n\t\t\tchars += block.name.length + safeJsonStringify(block.arguments).length;\n\t\t}\n\t}\n\treturn Math.ceil(chars / CHARS_PER_TOKEN);\n}\n\nfunction getLastAssistantUsageInfo(messages: readonly Message[]): { usage: Usage; index: number } | undefined {\n\tlet latestPrefixTimestamp = Number.NEGATIVE_INFINITY;\n\tlet usageInfo: { usage: Usage; index: number } | undefined;\n\n\tfor (let i = 0; i < messages.length; i++) {\n\t\tconst message = messages[i];\n\t\tif (message.role === \"assistant\") {\n\t\t\tconst assistant = message as AssistantMessage;\n\t\t\t// A newer prefix message was inserted after this response (for example, a\n\t\t\t// compaction summary), so its usage cannot describe the current prefix.\n\t\t\tconst usageAppliesToPrefix = assistant.timestamp >= latestPrefixTimestamp;\n\t\t\tif (\n\t\t\t\tusageAppliesToPrefix &&\n\t\t\t\tassistant.stopReason !== \"aborted\" &&\n\t\t\t\tassistant.stopReason !== \"error\" &&\n\t\t\t\tcalculateContextTokens(assistant.usage) > 0\n\t\t\t) {\n\t\t\t\tusageInfo = { usage: assistant.usage, index: i };\n\t\t\t}\n\t\t}\n\t\tlatestPrefixTimestamp = Math.max(latestPrefixTimestamp, message.timestamp);\n\t}\n\n\treturn usageInfo;\n}\n\nfunction estimateMessages(messages: readonly Message[]): ContextUsageEstimate {\n\tconst usageInfo = getLastAssistantUsageInfo(messages);\n\tif (usageInfo) {\n\t\tconst usageTokens = calculateContextTokens(usageInfo.usage);\n\t\tlet trailingTokens = 0;\n\t\tfor (let i = usageInfo.index + 1; i < messages.length; i++) {\n\t\t\ttrailingTokens += estimateMessageTokens(messages[i]);\n\t\t}\n\t\treturn { tokens: usageTokens + trailingTokens, usageTokens, trailingTokens, lastUsageIndex: usageInfo.index };\n\t}\n\n\tlet tokens = 0;\n\tfor (const message of messages) tokens += estimateMessageTokens(message);\n\treturn { tokens, usageTokens: 0, trailingTokens: tokens, lastUsageIndex: null };\n}\n\nfunction estimateToolsTokens(tools: readonly Tool[] | undefined): number {\n\tif (!tools || tools.length === 0) return 0;\n\treturn estimateTextTokens(safeJsonStringify(tools));\n}\n\nfunction isMessageArray(value: Context | readonly Message[]): value is readonly Message[] {\n\treturn Array.isArray(value);\n}\n\nexport function estimateContextTokens(context: Context | readonly Message[]): ContextUsageEstimate {\n\tif (isMessageArray(context)) return estimateMessages(context);\n\n\tconst estimate = estimateMessages(context.messages);\n\tif (estimate.lastUsageIndex !== null) {\n\t\tconst addedNames = new Set(\n\t\t\tcontext.messages\n\t\t\t\t.slice(estimate.lastUsageIndex + 1)\n\t\t\t\t.filter((message) => message.role === \"toolResult\")\n\t\t\t\t.flatMap((message) => message.addedToolNames ?? []),\n\t\t);\n\t\tconst addedToolTokens = estimateToolsTokens(context.tools?.filter((tool) => addedNames.has(tool.name)));\n\t\treturn {\n\t\t\ttokens: estimate.tokens + addedToolTokens,\n\t\t\tusageTokens: estimate.usageTokens,\n\t\t\ttrailingTokens: estimate.trailingTokens + addedToolTokens,\n\t\t\tlastUsageIndex: estimate.lastUsageIndex,\n\t\t};\n\t}\n\n\tconst prefixTokens =\n\t\t(context.systemPrompt ? estimateTextTokens(context.systemPrompt) : 0) + estimateToolsTokens(context.tools);\n\n\treturn {\n\t\ttokens: estimate.tokens + prefixTokens,\n\t\tusageTokens: estimate.usageTokens,\n\t\ttrailingTokens: estimate.trailingTokens + prefixTokens,\n\t\tlastUsageIndex: estimate.lastUsageIndex,\n\t};\n}\n"]}