// LLM utilities: model invocation via direct API

use crate::store::Store;

use regex::Regex;
use std::fs;

/// Simple LLM call for non-agent uses (audit, digest, compare).
/// Logs to llm-logs/{caller}/ file.
pub(crate) fn call_simple(caller: &str, prompt: &str) -> Result<String, String> {
    let log_dir = crate::store::memory_dir().join("llm-logs").join(caller);
    fs::create_dir_all(&log_dir).ok();
    let log_path = log_dir.join(format!("{}.txt", crate::store::compact_timestamp()));

    use std::io::Write;
    let log = move |msg: &str| {
        if let Ok(mut f) = fs::OpenOptions::new()
            .create(true).append(true).open(&log_path)
        {
            let _ = writeln!(f, "{}", msg);
        }
    };

    let prompts = vec![prompt.to_string()];
    super::api::call_api_with_tools_sync(caller, &prompts, None, &log)
}

/// Call a model using an agent definition's configuration (multi-step).
pub(crate) fn call_for_def_multi(
    def: &super::defs::AgentDef,
    prompts: &[String],
    log: &(dyn Fn(&str) + Sync),
) -> Result<String, String> {
    super::api::call_api_with_tools_sync(&def.agent, prompts, def.temperature, log)
}

/// Parse a JSON response, handling markdown fences.
pub(crate) fn parse_json_response(response: &str) -> Result<serde_json::Value, String> {
    let cleaned = response.trim();
    let cleaned = cleaned.strip_prefix("```json").unwrap_or(cleaned);
    let cleaned = cleaned.strip_prefix("```").unwrap_or(cleaned);
    let cleaned = cleaned.strip_suffix("```").unwrap_or(cleaned);
    let cleaned = cleaned.trim();

    if let Ok(v) = serde_json::from_str(cleaned) {
        return Ok(v);
    }

    // Try to find JSON object or array
    let re_obj = Regex::new(r"\{[\s\S]*\}").unwrap();
    let re_arr = Regex::new(r"\[[\s\S]*\]").unwrap();

    if let Some(m) = re_obj.find(cleaned)
        && let Ok(v) = serde_json::from_str(m.as_str()) {
            return Ok(v);
        }
    if let Some(m) = re_arr.find(cleaned)
        && let Ok(v) = serde_json::from_str(m.as_str()) {
            return Ok(v);
        }

    let preview = crate::util::first_n_chars(cleaned, 200);
    Err(format!("no valid JSON in response: {preview}..."))
}

/// Get all keys for prompt context.
pub(crate) fn semantic_keys(store: &Store) -> Vec<String> {
    let mut keys: Vec<String> = store.nodes.keys()
        .cloned()
        .collect();
    keys.sort();
    keys.truncate(200);
    keys
}