app.py

import streamlit as st
import json
import random

# Initialize session state
if 'camera_offset' not in st.session_state:
    st.session_state.camera_offset = {"x": 0, "y": 0}
if 'objects' not in st.session_state:
    st.session_state.objects = []

def update_canvas(direction=None, new_x=None, new_y=None, add_object=False, drag_x=0, drag_y=0):
    if direction:
        speed = 5
        if direction == "up":
            st.session_state.camera_offset["y"] -= speed
        elif direction == "down":
            st.session_state.camera_offset["y"] += speed
        elif direction == "left":
            st.session_state.camera_offset["x"] -= speed
        elif direction == "right":
            st.session_state.camera_offset["x"] += speed
    
    if new_x is not None and new_y is not None:
        st.session_state.camera_offset["x"] = int(new_x) - 300
        st.session_state.camera_offset["y"] = int(new_y) - 200
    
    if add_object:
        new_object = {
            "x": st.session_state.camera_offset["x"] + 300,
            "y": st.session_state.camera_offset["y"] + 200,
            "size": 10,
            "color": f"rgb({random.randint(0,255)},{random.randint(0,255)},{random.randint(0,255)})"
        }
        st.session_state.objects.append(new_object)
    
    st.session_state.camera_offset["x"] += int(drag_x)
    st.session_state.camera_offset["y"] += int(drag_y)

def render_canvas():
    state = json.dumps({
        "cameraOffset": st.session_state.camera_offset,
        "objects": st.session_state.objects
    })
    
    return f"""
    <div id="canvasContainer">
        <canvas id="infiniteCanvas" width="600" height="400" style="border: 1px solid black; cursor: grab;"></canvas>
        <p id="coordinates">Player coordinates: X: {300 + st.session_state.camera_offset['x']}, Y: {200 + st.session_state.camera_offset['y']}</p>
    </div>
    <script>
    let cameraOffset = {st.session_state.camera_offset};
    let objects = {json.dumps(st.session_state.objects)};
    const playerSize = 20;
    const gridSize = 50;
    const canvas = document.getElementById('infiniteCanvas');
    const ctx = canvas.getContext('2d');
    const coordsDisplay = document.getElementById('coordinates');

    function drawGrid() {{
        ctx.strokeStyle = '#ddd';
        ctx.lineWidth = 0.5;
        for (let x = -cameraOffset.x % gridSize; x < canvas.width; x += gridSize) {{
            ctx.beginPath();
            ctx.moveTo(x, 0);
            ctx.lineTo(x, canvas.height);
            ctx.stroke();
        }}
        for (let y = -cameraOffset.y % gridSize; y < canvas.height; y += gridSize) {{
            ctx.beginPath();
            ctx.moveTo(0, y);
            ctx.lineTo(canvas.width, y);
            ctx.stroke();
        }}
    }}

    function drawPlayer() {{
        ctx.fillStyle = 'red';
        ctx.fillRect(canvas.width / 2 - playerSize / 2, canvas.height / 2 - playerSize / 2, playerSize, playerSize);
    }}

    function drawObjects() {{
        objects.forEach(obj => {{
            ctx.fillStyle = obj.color;
            ctx.fillRect(
                obj.x - cameraOffset.x,
                obj.y - cameraOffset.y,
                obj.size,
                obj.size
            );
        }});
    }}

    function draw() {{
        ctx.clearRect(0, 0, canvas.width, canvas.height);
        drawGrid();
        drawObjects();
        drawPlayer();
    }}

    draw();
    </script>
    """

st.title("Infinite Canvas")

# Render canvas
st.components.v1.html(render_canvas(), height=450)

# Control buttons
col1, col2, col3, col4 = st.columns(4)
with col1:
    if st.button("↑"):
        update_canvas(direction="up")
with col2:
    if st.button("↓"):
        update_canvas(direction="down")
with col3:
    if st.button("←"):
        update_canvas(direction="left")
with col4:
    if st.button("→"):
        update_canvas(direction="right")

# Go to coordinates
col1, col2, col3 = st.columns(3)
with col1:
    new_x = st.number_input("X Coordinate", value=300 + st.session_state.camera_offset['x'])
with col2:
    new_y = st.number_input("Y Coordinate", value=200 + st.session_state.camera_offset['y'])
with col3:
    if st.button("Go to Coordinates"):
        update_canvas(new_x=new_x, new_y=new_y)

# Add object button
if st.button("Add Object"):
    update_canvas(add_object=True)

# Drag sliders
drag_x = st.slider("Drag X", -50, 50, 0)
drag_y = st.slider("Drag Y", -50, 50, 0)

if drag_x != 0 or drag_y != 0:
    update_canvas(drag_x=drag_x, drag_y=drag_y)
    st.experimental_rerun()

# Force rerun to update canvas
if st.button("Update Canvas"):
    st.experimental_rerun()