{
  "schema_version": 1,
  "diagram_type": "architecture",
  "meta": {
    "title": "Canvas System Architecture",
    "output": "assets/diagrams/canvas-architecture.html",
    "quality_profile": "showcase",
    "views": [
      {
        "id": "production-edge",
        "label": "Production Cloudflare Edge",
        "focus": ["browser", "pages_cdn", "functions", "worker_api", "catalogue_do", "board_do"],
        "note": "Follow client requests through Pages CDN, Functions edge router, and Durable Objects."
      },
      {
        "id": "realtime-sync",
        "label": "Real-time Collaboration",
        "focus": ["browser", "worker_api", "board_do"],
        "note": "Direct live WebSocket broadcast loop between Board DO and connected browsers."
      },
      {
        "id": "local-development",
        "label": "Local Development",
        "focus": ["local_browser", "go_server", "data_files"],
        "note": "Zero-dependency local Go daemon persisting state to local disk and streaming SSE."
      }
    ]
  },
  "components": [
    {
      "id": "browser",
      "type": "frontend",
      "label": "Web Browser",
      "sublabel": "HTML5 Canvas UI",
      "tag": "Live Client",
      "pos": [40, 190],
      "size": [130, 60]
    },
    {
      "id": "pages_cdn",
      "type": "cloud",
      "label": "Cloudflare Pages",
      "sublabel": "Static Assets CDN",
      "brand": "cloudflare",
      "pos": [260, 90],
      "size": [140, 60]
    },
    {
      "id": "functions",
      "type": "backend",
      "label": "Pages Functions",
      "sublabel": "functions/[[path]].js",
      "brand": "cloudflare",
      "pos": [260, 270],
      "size": [140, 60]
    },
    {
      "id": "worker_api",
      "type": "backend",
      "label": "Worker API",
      "sublabel": "canvas-rishirajpal-api",
      "brand": "cloudflare",
      "pos": [480, 270],
      "size": [150, 60]
    },
    {
      "id": "catalogue_do",
      "type": "database",
      "label": "Catalogue DO",
      "sublabel": "Registry & TTL Alarms",
      "brand": "sqlite",
      "pos": [720, 150],
      "size": [150, 60]
    },
    {
      "id": "board_do",
      "type": "database",
      "label": "Board DO",
      "sublabel": "SQLite Grid & WS Hub",
      "brand": "sqlite",
      "pos": [720, 310],
      "size": [150, 60]
    },
    {
      "id": "local_browser",
      "type": "frontend",
      "label": "Local Browser",
      "sublabel": "localhost:8080",
      "tag": "Dev Client",
      "pos": [40, 480],
      "size": [130, 60]
    },
    {
      "id": "go_server",
      "type": "backend",
      "label": "Go Local Server",
      "sublabel": "cmd/canvas (SSE)",
      "brand": "go",
      "pos": [260, 480],
      "size": [140, 60]
    },
    {
      "id": "data_files",
      "type": "database",
      "label": "Disk Storage",
      "sublabel": "data/*.json files",
      "pos": [480, 480],
      "size": [140, 60]
    }
  ],
  "boundaries": [
    {
      "kind": "region",
      "label": "Cloudflare Global Edge Platform",
      "wraps": ["pages_cdn", "functions", "worker_api", "catalogue_do", "board_do"]
    },
    {
      "kind": "security-group",
      "label": "Local Development Sandbox",
      "wraps": ["local_browser", "go_server", "data_files"]
    }
  ],
  "connections": [
    {
      "id": "browser-static",
      "from": "browser",
      "to": "pages_cdn",
      "label": "static assets"
    },
    {
      "id": "browser-functions",
      "from": "browser",
      "to": "functions",
      "label": "HTTP & WS",
      "labelDy": 20
    },
    {
      "id": "functions-worker",
      "from": "functions",
      "to": "worker_api",
      "label": "CANVAS_API"
    },
    {
      "id": "worker-catalogue",
      "from": "worker_api",
      "to": "catalogue_do",
      "label": "lookup",
      "fromSide": "top",
      "toSide": "left"
    },
    {
      "id": "worker-board",
      "from": "worker_api",
      "to": "board_do",
      "label": "dispatch & WS",
      "fromSide": "right",
      "toSide": "left"
    },
    {
      "id": "local-http",
      "from": "local_browser",
      "to": "go_server",
      "label": "HTTP & SSE"
    },
    {
      "id": "go-disk",
      "from": "go_server",
      "to": "data_files",
      "label": "JSON state"
    }
  ],
  "cards": [
    {
      "dot": "cyan",
      "title": "Cloudflare Edge",
      "items": [
        "Static HTML5, CSS, and JS served by global Cloudflare Pages CDN",
        "Pages Functions reverse-proxy API calls and upgrade WebSocket connections"
      ]
    },
    {
      "dot": "emerald",
      "title": "Durable Objects & SQLite",
      "items": [
        "Catalogue DO handles board discovery, 168-hour expiration, and midnight IST rotation",
        "Board DO coordinates 200x200 pixel state, atomic generations, and real-time WebSocket sync"
      ]
    },
    {
      "dot": "amber",
      "title": "Local Server Mode",
      "items": [
        "Standard Go binary (cmd/canvas) reproduces full API and static UI offline",
        "Stores board state in data/ directory and streams changes via Server-Sent Events"
      ]
    }
  ]
}