guise-ui 1.5.0

//! `AIMessage` — one turn in a conversation.
//!
//! A message is a role, a markdown body, and whatever the model attached to
//! it: reasoning, tool calls, sources, an error. Rather than model all of that
//! as fields, the body is what this draws and everything else arrives as
//! children — so a host that has some other thing to show under a reply
//! (a diff, an image, a rating widget) just adds it.
//!
//! The shape follows what people expect from a chat: the user's turn is a
//! contained bubble, the assistant's runs full width, and system and tool
//! turns are quiet marginalia.
//!
//! ```ignore
//! AIMessage::new(AIRole::Assistant, reply)
//!     .streaming(true)
//!     .child(AIToolCall::new("search").status(AIToolStatus::Running))
//! ```

use gpui::prelude::*;
use gpui::{div, px, AnyElement, App, IntoElement, SharedString, Window};

use super::AIStreamingText;
use crate::devtools::Probed;
use crate::icon::{Icon, IconName};
use crate::markdown::Markdown;
use crate::theme::{theme, ColorName, Size};

/// Who produced a turn.
#[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
pub enum AIRole {
    /// The person typing.
    #[default]
    User,
    /// The model.
    Assistant,
    /// Instructions the conversation runs under.
    System,
    /// The result handed back from a tool.
    Tool,
}

impl AIRole {
    /// The name shown above the turn.
    pub fn label(self) -> &'static str {
        match self {
            AIRole::User => "You",
            AIRole::Assistant => "Assistant",
            AIRole::System => "System",
            AIRole::Tool => "Tool",
        }
    }

    /// The glyph in the turn's gutter.
    pub fn icon(self) -> IconName {
        match self {
            AIRole::User => IconName::User,
            AIRole::Assistant => IconName::Sparkles,
            AIRole::System => IconName::Info,
            AIRole::Tool => IconName::Wrench,
        }
    }
}

/// One turn, rendered.
#[derive(IntoElement)]
pub struct AIMessage {
    role: AIRole,
    body: SharedString,
    /// Draw the body with a trailing caret, for a reply still arriving.
    streaming: bool,
    /// Shown instead of the body when the turn failed.
    error: Option<SharedString>,
    name: Option<SharedString>,
    meta: Option<SharedString>,
    avatar: bool,
    size: Size,
    /// Attachments — tool cards, sources, actions — drawn under the body.
    children: Vec<AnyElement>,
}

impl AIMessage {
    pub fn new(role: AIRole, body: impl Into<SharedString>) -> Self {
        AIMessage {
            role,
            body: body.into(),
            streaming: false,
            error: None,
            name: None,
            meta: None,
            avatar: true,
            size: Size::Sm,
            children: Vec::new(),
        }
    }

    /// The reply is still arriving: draw a caret after the last character.
    pub fn streaming(mut self, streaming: bool) -> Self {
        self.streaming = streaming;
        self
    }

    /// Replace the body with a failure notice. Whatever text had already
    /// arrived stays above it.
    pub fn error(mut self, error: impl Into<SharedString>) -> Self {
        self.error = Some(error.into());
        self
    }

    /// Override the role's default name — a model id, a person's name.
    pub fn name(mut self, name: impl Into<SharedString>) -> Self {
        self.name = Some(name.into());
        self
    }

    /// Trailing detail on the header row: a timestamp, a token count.
    pub fn meta(mut self, meta: impl Into<SharedString>) -> Self {
        self.meta = Some(meta.into());
        self
    }

    /// Hide the gutter icon and pull the body out to the full width.
    pub fn avatar(mut self, avatar: bool) -> Self {
        self.avatar = avatar;
        self
    }

    pub fn size(mut self, size: Size) -> Self {
        self.size = size;
        self
    }
}

impl ParentElement for AIMessage {
    fn extend(&mut self, elements: impl IntoIterator<Item = AnyElement>) {
        self.children.extend(elements);
    }
}

impl RenderOnce for AIMessage {
    fn render(self, _window: &mut Window, cx: &mut App) -> impl IntoElement {
        let t = theme(cx);
        let font = t.font_size(self.size);
        let radius = t.radius(Size::Md);
        let dimmed = t.dimmed().hsla();
        let border = t.border().hsla();
        let danger = t.danger().hsla();
        let bubble = t.surface_hover().hsla();
        let quiet = self.role == AIRole::System || self.role == AIRole::Tool;

        let header = div()
            .flex()
            .items_center()
            .gap(px(6.0))
            .text_size(px(t.font_size(Size::Xs)))
            .text_color(dimmed)
            // The role's label is already `&'static str`, so the default
            // costs nothing and the override is a refcount bump.
            .child(
                self.name
                    .unwrap_or_else(|| SharedString::new_static(self.role.label())),
            )
            .when_some(self.meta, |row, meta| {
                row.child(div().child(SharedString::new_static("\u{00b7}")))
                    .child(meta)
            });

        let body = div()
            .w_full()
            .when(!self.body.is_empty(), |column| {
                column.child(if self.streaming {
                    AIStreamingText::new(self.body.clone())
                        .size(self.size)
                        .into_any_element()
                } else {
                    Markdown::new(self.body.clone())
                        .size(self.size)
                        .into_any_element()
                })
            })
            .when_some(self.error, |column, error| {
                column.child(
                    div()
                        .mt(px(6.0))
                        .flex()
                        .items_start()
                        .gap(px(6.0))
                        .text_size(px(t.font_size(Size::Xs)))
                        .text_color(danger)
                        .child(Icon::new(IconName::TriangleAlert).size(Size::Xs))
                        .child(error),
                )
            })
            .children(self.children);

        // The user's turn is a contained bubble; the assistant's is the page.
        // Anything else is marginalia, dimmed and small.
        let content = match self.role {
            AIRole::User => div()
                .max_w(px(560.0))
                .px(px(12.0))
                .py(px(8.0))
                .rounded(px(radius))
                .bg(bubble)
                .child(body),
            _ if quiet => div()
                .w_full()
                .px(px(10.0))
                .py(px(6.0))
                .rounded(px(radius))
                .border_1()
                .border_color(border)
                .text_color(dimmed)
                .child(body),
            _ => div().w_full().child(body),
        };

        let gutter = self.avatar.then(|| {
            div()
                .flex_none()
                .flex()
                .items_center()
                .justify_center()
                .w(px(24.0))
                .h(px(24.0))
                .rounded(px(12.0))
                .bg(bubble)
                .text_color(dimmed)
                .child(
                    Icon::new(self.role.icon())
                        .size(Size::Xs)
                        .color(ColorName::Gray),
                )
        });

        div()
            .flex()
            .flex_row()
            .items_start()
            .gap(px(10.0))
            .w_full()
            .text_size(px(font))
            .when(self.role == AIRole::User, |row| row.justify_end())
            .children(gutter.filter(|_| self.role != AIRole::User))
            .child(
                div()
                    .flex()
                    .flex_col()
                    .gap(px(2.0))
                    .flex_1()
                    .min_w(px(0.0))
                    .when(self.role == AIRole::User, |column| column.items_end())
                    .child(header)
                    .child(content),
            )
            .probe("AIMessage")
    }
}