use crate::memory::{self, Memory};
use std::fmt::Write;

/// Build context preamble by searching memory for relevant entries.
/// Entries with a hybrid score below `min_relevance_score` are dropped to
/// prevent unrelated memories from bleeding into the conversation.
pub(super) async fn build_context(
    mem: &dyn Memory,
    user_msg: &str,
    min_relevance_score: f64,
    session_id: Option<&str>,
) -> String {
    let mut context = String::new();

    // Pull relevant memories for this message
    if let Ok(entries) = mem.recall(user_msg, 5, session_id).await {
        let relevant: Vec<_> = entries
            .iter()
            .filter(|e| match e.score {
                Some(score) => score >= min_relevance_score,
                None => true,
            })
            .collect();

        if !relevant.is_empty() {
            context.push_str("[Memory context]\n");
            for entry in &relevant {
                if memory::is_assistant_autosave_key(&entry.key) {
                    continue;
                }
                let _ = writeln!(context, "- {}: {}", entry.key, entry.content);
            }
            if context == "[Memory context]\n" {
                context.clear();
            } else {
                context.push('\n');
            }
        }
    }

    context
}

/// Build hardware datasheet context from RAG when peripherals are enabled.
/// Includes pin-alias lookup (e.g. "red_led" → 13) when query matches, plus retrieved chunks.
pub(super) fn build_hardware_context(
    rag: &crate::rag::HardwareRag,
    user_msg: &str,
    boards: &[String],
    chunk_limit: usize,
) -> String {
    if rag.is_empty() || boards.is_empty() {
        return String::new();
    }

    let mut context = String::new();

    // Pin aliases: when user says "red led", inject "red_led: 13" for matching boards
    let pin_ctx = rag.pin_alias_context(user_msg, boards);
    if !pin_ctx.is_empty() {
        context.push_str(&pin_ctx);
    }

    let chunks = rag.retrieve(user_msg, boards, chunk_limit);
    if chunks.is_empty() && pin_ctx.is_empty() {
        return String::new();
    }

    if !chunks.is_empty() {
        context.push_str("[Hardware documentation]\n");
    }
    for chunk in chunks {
        let board_tag = chunk.board.as_deref().unwrap_or("generic");
        let _ = writeln!(
            context,
            "--- {} ({}) ---\n{}\n",
            chunk.source, board_tag, chunk.content
        );
    }
    context.push('\n');
    context
}