cadcraft/crates/mcp/src/tools.rs

//! MCP tool definitions and dispatch.

use serde_json::{Value, json};

use crate::backend::Backend;

pub fn tool_definitions(has_ui: bool) -> Value {
    let mut tools = vec![
        json!({"name": "command_line", "description": "Type one line at the CADCraft command line, exactly as a user would at an AutoCAD-style prompt. Starts commands by name or alias (LINE, L, CIRCLE, C, PLINE, RECTANG, MOVE, TRIM, OFFSET, ZOOM…) and answers the active prompt: points `x,y`, relative `@dx,dy`, polar `@dist<angle`, distances, keywords (e.g. `c` for Close), empty text = Enter. Spaces act as Enter, so `circle 0,0 5` works in one call. Returns the new prompt and command-line output.",
            "inputSchema": {"type": "object", "properties": {"text": {"type": "string"}}, "required": ["text"]}}),
        json!({"name": "script", "description": "Run a multi-line script (like an AutoCAD .scr file): one or more inputs per line, blank line = Enter.",
            "inputSchema": {"type": "object", "properties": {"text": {"type": "string"}}, "required": ["text"]}}),
        json!({"name": "execute", "description": "Run any command with JSON parameters (no prompts or dialogs). Use list_commands to find ids and parameter docs. Examples: line {points:[[0,0],[10,0]]}, circle {center:[0,0], radius:5}, layer.new {name:\"Walls\", color:\"red\", current:true}, move {handles:[\"10A\"], delta:[5,0]}, zoom {mode:\"extents\"}.",
            "inputSchema": {"type": "object", "properties": {"command": {"type": "string"}, "params": {"type": "object"}}, "required": ["command"]}}),
        json!({"name": "list_commands", "description": "List commands with ids, labels, menu paths, aliases and parameter docs. Optional substring filter.",
            "inputSchema": {"type": "object", "properties": {"filter": {"type": "string"}}}}),
        json!({"name": "inspect_drawing", "description": "Summary of the active drawing: entity counts, extents, layers, styles, blocks, layouts, selection, undo history and (optionally) entities with handles and geometry.",
            "inputSchema": {"type": "object", "properties": {"entities": {"type": "boolean"}, "limit": {"type": "integer"}}}}),
        json!({"name": "query_entities", "description": "Entities filtered by type (Line, Circle, Polyline…), layer and/or a window [[x0,y0],[x1,y1]].",
            "inputSchema": {"type": "object", "properties": {"type": {"type": "string"}, "layer": {"type": "string"}, "window": {"type": "array"}, "limit": {"type": "integer"}}}}),
        json!({"name": "render", "description": "Render the active drawing to a PNG (fitted to extents by default) and return it as an image.",
            "inputSchema": {"type": "object", "properties": {"width": {"type": "integer"}, "height": {"type": "integer"}, "fit": {"type": "boolean"}, "path": {"type": "string"}}}}),
        json!({"name": "new_drawing", "description": "Create a new drawing (imperial by default, or metric).",
            "inputSchema": {"type": "object", "properties": {"metric": {"type": "boolean"}}}}),
        json!({"name": "open", "description": "Open a DXF file.", "inputSchema": {"type": "object", "properties": {"path": {"type": "string"}}, "required": ["path"]}}),
        json!({"name": "save", "description": "Save the drawing (DXF; .svg/.png export by extension).", "inputSchema": {"type": "object", "properties": {"path": {"type": "string"}}}}),
        json!({"name": "cancel", "description": "Press Escape: cancel the running command (or clear the selection).", "inputSchema": {"type": "object", "properties": {}}}),
    ];
    if has_ui {
        tools.push(json!({"name": "screenshot", "description": "Screenshot the CADCraft window (PNG).", "inputSchema": {"type": "object", "properties": {"path": {"type": "string"}}}}));
        tools.push(json!({"name": "ui_inspect", "description": "UI state: panels, canvas rect, view, cursor and snap, performance.", "inputSchema": {"type": "object", "properties": {}}}));
        tools.push(json!({"name": "ui_click", "description": "Click in the drawing area at world coordinates (or screen with space:\"screen\"). Right button = Enter.", "inputSchema": {"type": "object", "properties": {"x": {"type": "number"}, "y": {"type": "number"}, "space": {"type": "string"}, "button": {"type": "string"}}, "required": ["x", "y"]}}));
    }
    json!({ "tools": tools })
}

fn text(v: &Value) -> Value {
    json!({"content": [{"type": "text", "text": serde_json::to_string_pretty(v).unwrap_or_default()}]})
}

fn err_text(e: &str) -> Value {
    json!({"content": [{"type": "text", "text": e}], "isError": true})
}

pub fn call_tool(b: &mut dyn Backend, name: &str, args: &Value) -> Value {
    let a = if args.is_object() { args.clone() } else { json!({}) };
    let r = match name {
        "command_line" => b.call("cmdline.input", a),
        "script" => b.call("cmdline.script", a),
        "execute" => b.call(
            "engine.execute",
            json!({"command": a.get("command").cloned().unwrap_or(Value::Null), "params": a.get("params").cloned().unwrap_or(json!({}))}),
        ),
        "list_commands" => b.call("engine.commands", json!({})).map(|v| {
            let f = a.get("filter").and_then(Value::as_str).map(str::to_ascii_lowercase);
            match (v, f) {
                (Value::Array(items), Some(f)) => {
                    Value::Array(items.into_iter().filter(|c| c.to_string().to_ascii_lowercase().contains(&f)).collect())
                }
                (v, _) => v,
            }
        }),
        "inspect_drawing" => b.call("drawing.inspect", a),
        "query_entities" => b.call("engine.execute", json!({"command": "entities", "params": a})),
        "new_drawing" => b.call("engine.execute", json!({"command": "new", "params": a})),
        "open" => b.call("app.open", a),
        "save" => b.call("app.save", a),
        "cancel" => b.call("cmdline.key", json!({"key": "escape"})),
        "screenshot" => b.call("ui.screenshot", a),
        "ui_inspect" => b.call("ui.inspect", json!({})),
        "ui_click" => b.call("ui.pointer", a),
        "render" => {
            return match b.call("ui.render", a) {
                Ok(v) => match v.get("pngBase64").and_then(Value::as_str) {
                    Some(data) => json!({"content": [{"type": "image", "data": data, "mimeType": "image/png"}]}),
                    None => text(&v),
                },
                Err(e) => err_text(&e),
            };
        }
        other => return err_text(&format!("unknown tool `{other}`")),
    };
    match r {
        Ok(v) => text(&v),
        Err(e) => err_text(&e),
    }
}