nms-copilot 0.1.0

//! Context-aware REPL prompt.
//!
//! Displays current galaxy, active biome filter, and model size.
//! Format: `[Euclid | Lush | 644 planets] 🚀 `

use std::borrow::Cow;

use reedline::{Prompt, PromptEditMode, PromptHistorySearch, PromptHistorySearchStatus};

use crate::session::SessionState;

/// A snapshot of session state used to render the prompt.
///
/// We take a snapshot rather than holding a reference to SessionState
/// because reedline's Prompt trait requires `&self` (not mutable),
/// and the session state changes between prompts.
#[derive(Debug, Clone)]
pub struct PromptState {
    pub galaxy_name: String,
    pub biome_filter: Option<String>,
    pub planet_count: usize,
}

impl PromptState {
    /// Build a prompt state snapshot from the current session.
    pub fn from_session(session: &SessionState) -> Self {
        Self {
            galaxy_name: session.galaxy.name.to_string(),
            biome_filter: session.biome_filter.map(|b| format!("{b:?}")),
            planet_count: session.planet_count,
        }
    }
}

/// Custom REPL prompt.
pub struct CopilotPrompt {
    state: PromptState,
}

impl CopilotPrompt {
    pub fn new(state: PromptState) -> Self {
        Self { state }
    }

    /// Update the prompt state (called before each read_line).
    pub fn update(&mut self, state: PromptState) {
        self.state = state;
    }

    fn render_left(&self) -> String {
        let mut parts = vec![self.state.galaxy_name.clone()];

        if let Some(ref biome) = self.state.biome_filter {
            parts.push(biome.clone());
        }

        parts.push(format!("{} planets", self.state.planet_count));

        format!("[{}] 🚀", parts.join(" | "))
    }
}

impl Prompt for CopilotPrompt {
    fn render_prompt_left(&self) -> Cow<'_, str> {
        Cow::Owned(self.render_left())
    }

    fn render_prompt_right(&self) -> Cow<'_, str> {
        Cow::Borrowed("")
    }

    fn render_prompt_indicator(&self, _edit_mode: PromptEditMode) -> Cow<'_, str> {
        Cow::Borrowed(" ")
    }

    fn render_prompt_multiline_indicator(&self) -> Cow<'_, str> {
        Cow::Borrowed("... ")
    }

    fn render_prompt_history_search_indicator(
        &self,
        history_search: PromptHistorySearch,
    ) -> Cow<'_, str> {
        let prefix = match history_search.status {
            PromptHistorySearchStatus::Passing => "",
            PromptHistorySearchStatus::Failing => "(failed) ",
        };
        Cow::Owned(format!("{prefix}(search: {}) ", history_search.term))
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_prompt_basic() {
        let state = PromptState {
            galaxy_name: "Euclid".into(),
            biome_filter: None,
            planet_count: 644,
        };
        let prompt = CopilotPrompt::new(state);
        let left = prompt.render_prompt_left();
        assert_eq!(left.as_ref(), "[Euclid | 644 planets] 🚀");
    }

    #[test]
    fn test_prompt_with_biome_filter() {
        let state = PromptState {
            galaxy_name: "Euclid".into(),
            biome_filter: Some("Lush".into()),
            planet_count: 42,
        };
        let prompt = CopilotPrompt::new(state);
        let left = prompt.render_prompt_left();
        assert_eq!(left.as_ref(), "[Euclid | Lush | 42 planets] 🚀");
    }

    #[test]
    fn test_prompt_different_galaxy() {
        let state = PromptState {
            galaxy_name: "Hilbert Dimension".into(),
            biome_filter: None,
            planet_count: 100,
        };
        let prompt = CopilotPrompt::new(state);
        let left = prompt.render_prompt_left();
        assert!(left.contains("Hilbert Dimension"));
    }

    #[test]
    fn test_prompt_indicator_is_space() {
        let state = PromptState {
            galaxy_name: "Euclid".into(),
            biome_filter: None,
            planet_count: 0,
        };
        let prompt = CopilotPrompt::new(state);
        assert_eq!(
            prompt
                .render_prompt_indicator(PromptEditMode::Default)
                .as_ref(),
            " "
        );
    }

    #[test]
    fn test_prompt_update() {
        let state1 = PromptState {
            galaxy_name: "Euclid".into(),
            biome_filter: None,
            planet_count: 100,
        };
        let mut prompt = CopilotPrompt::new(state1);
        assert!(prompt.render_prompt_left().contains("100 planets"));

        let state2 = PromptState {
            galaxy_name: "Euclid".into(),
            biome_filter: Some("Toxic".into()),
            planet_count: 200,
        };
        prompt.update(state2);
        let left = prompt.render_prompt_left();
        assert!(left.contains("200 planets"));
        assert!(left.contains("Toxic"));
    }

    #[test]
    fn test_prompt_state_from_session() {
        let json = r#"{
            "Version": 4720, "Platform": "Mac|Final", "ActiveContext": "Main",
            "CommonStateData": {"SaveName": "Test", "TotalPlayTime": 100},
            "BaseContext": {
                "GameMode": 1,
                "PlayerStateData": {
                    "UniverseAddress": {"RealityIndex": 0, "GalacticAddress": {"VoxelX": 0, "VoxelY": 0, "VoxelZ": 0, "SolarSystemIndex": 1, "PlanetIndex": 0}},
                    "Units": 0, "Nanites": 0, "Specials": 0,
                    "PersistentPlayerBases": []
                }
            },
            "ExpeditionContext": {"GameMode": 6, "PlayerStateData": {"UniverseAddress": {"RealityIndex": 0, "GalacticAddress": {"VoxelX": 0, "VoxelY": 0, "VoxelZ": 0, "SolarSystemIndex": 0, "PlanetIndex": 0}}, "Units": 0, "Nanites": 0, "Specials": 0, "PersistentPlayerBases": []}},
            "DiscoveryManagerData": {"DiscoveryData-v1": {"ReserveStore": 0, "ReserveManaged": 0, "Store": {"Record": [
                {"DD": {"UA": "0x050003AB8C07", "DT": "SolarSystem", "VP": []}, "DM": {}, "OWS": {"LID":"","UID":"1","USN":"","PTK":"ST","TS":0}, "FL": {"U": 1}}
            ]}}}
        }"#;
        let save = nms_save::parse_save(json.as_bytes()).unwrap();
        let model = nms_graph::GalaxyModel::from_save(&save);
        let session = crate::session::SessionState::from_model(&model);
        let ps = PromptState::from_session(&session);
        assert_eq!(ps.galaxy_name, "Euclid");
        assert!(ps.biome_filter.is_none());
    }
}