// dcode - Gcode visualization and generation

class GcodeViewer {
    constructor(canvas) {
        this.canvas = canvas;
        this.ctx = canvas.getContext('2d');
        this.paths = [];
        this.zoom = 1;
        this.panX = 0;
        this.panY = 0;
        this.isDragging = false;
        this.lastMouse = { x: 0, y: 0 };
        
        // Work area bounds (from machine config)
        this.bounds = {
            left: -420.5,
            right: 420.5,
            top: 594.5,
            bottom: -594.5
        };
        
        this.resize();
        this.setupEvents();
        this.draw();
    }
    
    resize() {
        const rect = this.canvas.getBoundingClientRect();
        this.canvas.width = rect.width * window.devicePixelRatio;
        this.canvas.height = rect.height * window.devicePixelRatio;
        this.ctx.scale(window.devicePixelRatio, window.devicePixelRatio);
    }
    
    setupEvents() {
        this.canvas.addEventListener('wheel', (e) => {
            e.preventDefault();
            const delta = e.deltaY > 0 ? 0.9 : 1.1;
            this.zoom *= delta;
            this.zoom = Math.max(0.1, Math.min(10, this.zoom));
            this.draw();
        });
        
        this.canvas.addEventListener('mousedown', (e) => {
            this.isDragging = true;
            this.lastMouse = { x: e.clientX, y: e.clientY };
        });
        
        this.canvas.addEventListener('mousemove', (e) => {
            if (this.isDragging) {
                this.panX += e.clientX - this.lastMouse.x;
                this.panY += e.clientY - this.lastMouse.y;
                this.lastMouse = { x: e.clientX, y: e.clientY };
                this.draw();
            }
        });
        
        this.canvas.addEventListener('mouseup', () => this.isDragging = false);
        this.canvas.addEventListener('mouseleave', () => this.isDragging = false);
        
        window.addEventListener('resize', () => {
            this.resize();
            this.draw();
        });
    }
    
    parseGcode(gcode) {
        this.paths = [];
        let currentPath = [];
        let x = 0, y = 0;
        let penDown = false;
        
        const lines = gcode.split('\n');
        for (const line of lines) {
            const trimmed = line.trim();
            if (!trimmed || trimmed.startsWith(';')) continue;
            
            // Pen up/down
            if (trimmed.includes('M280')) {
                const match = trimmed.match(/S(\d+)/);
                if (match) {
                    const angle = parseInt(match[1]);
                    const wasDown = penDown;
                    penDown = angle < 50; // Down if angle < 50
                    
                    if (wasDown && !penDown && currentPath.length > 1) {
                        this.paths.push([...currentPath]);
                        currentPath = [];
                    }
                }
            }
            
            // Movement
            const xMatch = trimmed.match(/X([-\d.]+)/i);
            const yMatch = trimmed.match(/Y([-\d.]+)/i);
            
            if (xMatch) x = parseFloat(xMatch[1]);
            if (yMatch) y = parseFloat(yMatch[1]);
            
            if ((xMatch || yMatch) && penDown) {
                currentPath.push({ x, y });
            }
        }
        
        if (currentPath.length > 1) {
            this.paths.push(currentPath);
        }
        
        this.resetView();
        this.draw();
    }
    
    resetView() {
        this.zoom = 1;
        this.panX = 0;
        this.panY = 0;
    }
    
    draw() {
        const w = this.canvas.width / window.devicePixelRatio;
        const h = this.canvas.height / window.devicePixelRatio;
        
        this.ctx.fillStyle = '#111';
        this.ctx.fillRect(0, 0, w, h);
        
        this.ctx.save();
        this.ctx.translate(w / 2 + this.panX, h / 2 + this.panY);
        
        // Scale to fit work area
        const boundsW = this.bounds.right - this.bounds.left;
        const boundsH = this.bounds.top - this.bounds.bottom;
        const scale = Math.min(w / boundsW, h / boundsH) * 0.9 * this.zoom;
        
        this.ctx.scale(scale, -scale); // Flip Y
        
        // Draw work area
        this.ctx.strokeStyle = '#333';
        this.ctx.lineWidth = 1 / scale;
        this.ctx.strokeRect(
            this.bounds.left,
            this.bounds.bottom,
            boundsW,
            boundsH
        );
        
        // Draw paths
        this.ctx.strokeStyle = '#4ade80';
        this.ctx.lineWidth = 1 / scale;
        this.ctx.lineCap = 'round';
        this.ctx.lineJoin = 'round';
        
        for (const path of this.paths) {
            if (path.length < 2) continue;
            this.ctx.beginPath();
            this.ctx.moveTo(path[0].x, path[0].y);
            for (let i = 1; i < path.length; i++) {
                this.ctx.lineTo(path[i].x, path[i].y);
            }
            this.ctx.stroke();
        }
        
        this.ctx.restore();
    }
    
    toSVG() {
        const boundsW = this.bounds.right - this.bounds.left;
        const boundsH = this.bounds.top - this.bounds.bottom;
        
        let svg = `<svg xmlns="http://www.w3.org/2000/svg" viewBox="${this.bounds.left} ${-this.bounds.top} ${boundsW} ${boundsH}">`;
        svg += `<rect x="${this.bounds.left}" y="${-this.bounds.top}" width="${boundsW}" height="${boundsH}" fill="none" stroke="#333"/>`;
        
        for (const path of this.paths) {
            if (path.length < 2) continue;
            const d = path.map((p, i) => `${i === 0 ? 'M' : 'L'}${p.x},${-p.y}`).join(' ');
            svg += `<path d="${d}" fill="none" stroke="#4ade80" stroke-width="1"/>`;
        }
        
        svg += '</svg>';
        return svg;
    }
}

// Main app
let viewer;
let currentGcode = '';

document.addEventListener('DOMContentLoaded', () => {
    const canvas = document.getElementById('workplane');
    viewer = new GcodeViewer(canvas);
    
    document.getElementById('zoom-in').onclick = () => {
        viewer.zoom *= 1.2;
        viewer.draw();
    };
    
    document.getElementById('zoom-out').onclick = () => {
        viewer.zoom *= 0.8;
        viewer.draw();
    };
    
    document.getElementById('reset-view').onclick = () => {
        viewer.resetView();
        viewer.draw();
    };
    
    document.getElementById('generate').onclick = async () => {
        const prompt = document.getElementById('prompt').value;
        if (!prompt) return;
        
        document.getElementById('status').textContent = 'Generating...';
        document.getElementById('validation').textContent = '';
        
        // TODO: Call actual inference API
        // For now, show placeholder
        document.getElementById('status').textContent = 'API endpoint not configured. Deploy with Gradio backend.';
    };
    
    document.getElementById('download-gcode').onclick = () => {
        if (!currentGcode) return;
        const blob = new Blob([currentGcode], { type: 'text/plain' });
        const url = URL.createObjectURL(blob);
        const a = document.createElement('a');
        a.href = url;
        a.download = 'output.gcode';
        a.click();
        URL.revokeObjectURL(url);
    };
    
    document.getElementById('download-svg').onclick = () => {
        if (!viewer.paths.length) return;
        const svg = viewer.toSVG();
        const blob = new Blob([svg], { type: 'image/svg+xml' });
        const url = URL.createObjectURL(blob);
        const a = document.createElement('a');
        a.href = url;
        a.download = 'output.svg';
        a.click();
        URL.revokeObjectURL(url);
    };
});

// Expose for testing
window.loadGcode = (gcode) => {
    currentGcode = gcode;
    viewer.parseGcode(gcode);
    document.getElementById('download-gcode').disabled = false;
    document.getElementById('download-svg').disabled = false;
    document.getElementById('status').textContent = `Loaded ${viewer.paths.length} paths`;
    document.getElementById('validation').textContent = 'Machine compatible';
    document.getElementById('validation').className = 'valid';
};