fn try_into_generate()

in router/src/lib.rs [941:1036]
89 lines of code
4 McCabe index (conditional complexity)

    fn try_into_generate(self, infer: &Infer) -> Result<(GenerateRequest, bool), InferError> {
        let ChatRequest {
            model,
            max_tokens,
            messages,
            seed,
            stop,
            tools,
            tool_choice,
            tool_prompt,
            temperature,
            response_format,
            presence_penalty,
            frequency_penalty,
            top_p,
            top_logprobs,
            ..
        } = self;

        let repetition_penalty = presence_penalty.map(|x| x + 2.0);
        let max_new_tokens = max_tokens;
        let tool_prompt = tool_prompt
            .filter(|s| !s.is_empty())
            .unwrap_or_else(default_tool_prompt);
        let stop = stop.unwrap_or_default();
        // enable greedy only when temperature is 0
        let (do_sample, temperature) = match temperature {
            Some(0.0) => (false, None),
            other => (true, other),
        };

        if response_format.is_some() && tools.is_some() {
            return Err(InferError::ToolError(
                "Grammar and tools are mutually exclusive".into(),
            ));
        }

        let (inputs, grammar, using_tools) = match response_format {
            Some(format) => {
                let inputs = infer.apply_chat_template(messages, None)?;
                (inputs, Some(format), false)
            }
            None => {
                if let Some(tools) = tools {
                    match ToolGrammar::apply(tools, tool_choice)? {
                        Some((updated_tools, tool_schema)) => {
                            let grammar = GrammarType::Json(serde_json::json!(tool_schema));
                            let inputs: String = infer.apply_chat_template(
                                messages,
                                Some((updated_tools, tool_prompt)),
                            )?;
                            (inputs, Some(grammar), true)
                        }
                        None => {
                            // same as if no response_format or tools are set
                            let inputs = infer.apply_chat_template(messages, None)?;
                            (inputs, None, false)
                        }
                    }
                } else {
                    // if no response_format or tools are set simply apply the chat template to generate inputs
                    let inputs = infer.apply_chat_template(messages, None)?;
                    (inputs, None, false)
                }
            }
        };

        Ok((
            GenerateRequest {
                inputs: inputs.to_string(),
                add_special_tokens: false,
                parameters: GenerateParameters {
                    best_of: None,
                    temperature,
                    repetition_penalty,
                    frequency_penalty,
                    top_k: None,
                    top_p,
                    typical_p: None,
                    do_sample,
                    max_new_tokens,
                    return_full_text: None,
                    stop,
                    truncate: None,
                    watermark: false,
                    details: true,
                    decoder_input_details: false,
                    seed,
                    top_n_tokens: top_logprobs,
                    grammar,
                    adapter_id: model.filter(|m| *m != "tgi"),
                },
            },
            using_tools,
        ))
    }