# plastiq-router

* incredibly simple
* generate links from routes
* route parameters can be bound to the model

## rewrite + API simplication

Documentation for the 1.x API, can be found [here](https://github.com/featurist/plastiq-router/tree/v1).

## install

```bash
npm install plastiq-router
```

## example

You can see this example in action [here](http://www.featurist.co.uk/plastiq-router/example/)

* On the search page, notice how the URL changes as you type the search query.

```js
var plastiq = require('plastiq');
var h = plastiq.html;
var router = require('plastiq-router');

var routes = {
  root: router.route('/'),
  document: router.route('/document/:documentId'),
  search: router.route('/search')
};

router.start();

function render(model) {
  return h('div',
    renderLinks(),

    routes.root(function () {
      return h('ol.documents',
        model.documents.map(function (d, index) {
          return h('li', routes.document({documentId: index}).a(d.title));
        })
      );
    }),

    routes.document(function (params) {
      return renderDocument(model.documents[params.documentId]);
    }),

    routes.search({q: [model, 'query']}, function () {
      return h('div',
        h('h1', 'search'),
        h('input', {type: 'text', binding: [model, 'query']}),
        h('ol.results',
          model.searchDocuments(model.query).map(function (d) {
            return h('li', routes.document({documentId: d.id}).a(d.title));
          })
        )
      );
    })
  );
}

var model = {
  documents: [
    {id: 0, title: 'One', content: 'With just one polka dot, nothing can be achieved...'},
    {id: 1, title: 'Two', content: 'Sometimes I am two people. Johnny is the nice one...'},
    {id: 2, title: 'Three', content: 'To be stupid, selfish, and have good health are three requirements for happiness...'}
  ],
  searchDocuments: function (q) {
    var query = q? q.toLowerCase(): undefined;

    return this.documents.filter(function (d) {
      return query && d.title.toLowerCase().indexOf(query) >= 0 || d.content.toLowerCase().indexOf(query) >= 0;
    });
  }
};

function renderLinks() {
  return [
    routes.root().a('Home'),
    ' | ',
    routes.search().a('Search')
    ' | ',
    h('a', {href: 'https://github.com/featurist/plastiq-router'}, 'Github')
  ];
}

function renderDocument(d) {
  return h('.document',
    h('h1', d.title),
    h('.content', d.content)
  );
}

plastiq.append(document.body, render, model);
```

# API

## start

```js
router.start([options]);
```

Starts the router, adding event handlers for navigation.

* `options.history` - a history driver, currently two supported: `router.historyApi` (the default) and `router.hash`.

## stop

```js
router.stop();
```

Stops the router, removing event handlers for navigation. However does not remove existing routes, for that see `router.clear()`. This is particularly useful in test teardown.

## clear

```js
router.clear();
```

Clears all routes, removes event handlers. This is a complete teardown of the router, unlike `router.stop()`.

## create a route

```js
var route = router.route(pattern);
```

* `pattern` - the path pattern: `/` or `/path`, or `/path/:id`, or `/path/:id/:path*`
* `route` - the route, to be used in rendering, see below

## render a route

Routes can be rendered in two forms, passive and active. Passive routes do not modify the route parameters, active routes bind the model to the route parameters, effectively allowing the URL to change as the model changes.

### passive routes

```js
route(function (params) {
  return vdom;
});
```

If the route is active, returns the `vdom` passing the `params` taken from the route to the function. If the route is not active, `undefined` is returned.

* `params` - the params taken from the route, these can be from `:param` elements in the route pattern or query string parameters.

### active routes

```js
route(bindings, function () {
  return vdom;
});
```

* `bindings` - how the model binds on to the route parameters, takes the form:

    ```js
    {
      param1: [model, 'param1'],
      param2: [model, 'param2']
    }
    ```

    Where the object keys are the parameter names, and the values are the bindings onto the model.

### onarrival, ondeparture

You can setup or cleanup your model on the events `onarrival` and `ondeparture`:

```js
route(
  {
    onarrival: function () {
      // setup model
    },

    ondeparture: function () {
      // cleanup model
    }
  },
  functon () {
    return vdom;
  }
);
```

### under

Hierarchies of routes can be made by using `route.under(render)`, which executes the **render function** if the current location is on or under the route.

Let's say we have a route:

```js
var posts = router('/posts');
```

You can use `posts.under()` to match on URLs like `/posts` or `/posts/1` or `/posts/1/comments`, etc.

```js
function render() {
  return h('div',
    posts.under(function () {
      return h('div',
        posts(function () {
          // show all posts
        }),
        post(function (params) {
          // show just one post
        })
      });
    })
  );
}
```

If you don't pass a function to `route.under()` it will return an object with an `active` field, set to `true` if the current URL is on or under the route, or `false` otherwise.

## route instances

```js
var routeInstance = route([params]);
```

* `params` - an optional object containing the parameters of the form:

    ```js
    {param1: 'param1 value', param2: 'param2 value'}
    ```

Routes can be used from the server-side too! Although really only `href` works or makes any sense.

### href

```js
routeInstance.href
```

The root-relative HREF of the route - of the form `/path`.

### active

```js
routeInstance.active
```

Whether the route is currently active.

### push, replace

```js
routeInstance.push()
routeInstance.replace()
```

Either push the route onto the history stack (using history.pushState) or replace the current URL (using history.replaceState). Replace only works with the router.historyApi driver, which is the default.

### a, anchor, link

```js
routeInstance.link([options], contents, ...)
routeInstance.a([options], contents, ...)
```

Generates virtual DOM for an anchor for the route, passing the arguments to `h('a', options, contents, ...)`, but with the correct `href` and `onclick` properties set.