<?php

namespace Illuminate\View;

use Closure;
use Countable;
use Illuminate\Support\Arr;
use Illuminate\Support\Str;
use InvalidArgumentException;
use Illuminate\Contracts\Support\Arrayable;
use Illuminate\View\Engines\EngineResolver;
use Illuminate\Contracts\Events\Dispatcher;
use Illuminate\Contracts\Container\Container;
use Illuminate\Contracts\View\View as ViewContract;
use Illuminate\Contracts\View\Factory as FactoryContract;

class Factory implements FactoryContract
{
    /**
     * The engine implementation.
     *
     * @var \Illuminate\View\Engines\EngineResolver
     */
    protected $engines;

    /**
     * The view finder implementation.
     *
     * @var \Illuminate\View\ViewFinderInterface
     */
    protected $finder;

    /**
     * The event dispatcher instance.
     *
     * @var \Illuminate\Contracts\Events\Dispatcher
     */
    protected $events;

    /**
     * The IoC container instance.
     *
     * @var \Illuminate\Contracts\Container\Container
     */
    protected $container;

    /**
     * Data that should be available to all templates.
     *
     * @var array
     */
    protected $shared = [];

    /**
     * Array of registered view name aliases.
     *
     * @var array
     */
    protected $aliases = [];

    /**
     * All of the registered view names.
     *
     * @var array
     */
    protected $names = [];

    /**
     * The extension to engine bindings.
     *
     * @var array
     */
    protected $extensions = ['blade.php' => 'blade', 'php' => 'php'];

    /**
     * The view composer events.
     *
     * @var array
     */
    protected $composers = [];

    /**
     * All of the finished, captured sections.
     *
     * @var array
     */
    protected $sections = [];

    /**
     * The stack of in-progress sections.
     *
     * @var array
     */
    protected $sectionStack = [];

    /**
     * The stack of in-progress loops.
     *
     * @var array
     */
    protected $loopsStack = [];

    /**
     * All of the finished, captured push sections.
     *
     * @var array
     */
    protected $pushes = [];

    /**
     * The stack of in-progress push sections.
     *
     * @var array
     */
    protected $pushStack = [];

    /**
     * The number of active rendering operations.
     *
     * @var int
     */
    protected $renderCount = 0;

    /**
     * Create a new view factory instance.
     *
     * @param  \Illuminate\View\Engines\EngineResolver  $engines
     * @param  \Illuminate\View\ViewFinderInterface  $finder
     * @param  \Illuminate\Contracts\Events\Dispatcher  $events
     * @return void
     */
    public function __construct(EngineResolver $engines, ViewFinderInterface $finder, Dispatcher $events)
    {
        $this->finder = $finder;
        $this->events = $events;
        $this->engines = $engines;

        $this->share('__env', $this);
    }

    /**
     * Get the evaluated view contents for the given view.
     *
     * @param  string  $path
     * @param  array   $data
     * @param  array   $mergeData
     * @return \Illuminate\Contracts\View\View
     */
    public function file($path, $data = [], $mergeData = [])
    {
        $data = array_merge($mergeData, $this->parseData($data));

        $this->callCreator($view = new View($this, $this->getEngineFromPath($path), $path, $path, $data));

        return $view;
    }

    /**
     * Get the evaluated view contents for the given view.
     *
     * @param  string  $view
     * @param  array   $data
     * @param  array   $mergeData
     * @return \Illuminate\Contracts\View\View
     */
    public function make($view, $data = [], $mergeData = [])
    {
        if (isset($this->aliases[$view])) {
            $view = $this->aliases[$view];
        }

        $view = $this->normalizeName($view);

        $path = $this->finder->find($view);

        $data = array_merge($mergeData, $this->parseData($data));

        $this->callCreator($view = new View($this, $this->getEngineFromPath($path), $view, $path, $data));

        return $view;
    }

    /**
     * Normalize a view name.
     *
     * @param  string $name
     * @return string
     */
    protected function normalizeName($name)
    {
        $delimiter = ViewFinderInterface::HINT_PATH_DELIMITER;

        if (strpos($name, $delimiter) === false) {
            return str_replace('/', '.', $name);
        }

        list($namespace, $name) = explode($delimiter, $name);

        return $namespace.$delimiter.str_replace('/', '.', $name);
    }

    /**
     * Parse the given data into a raw array.
     *
     * @param  mixed  $data
     * @return array
     */
    protected function parseData($data)
    {
        return $data instanceof Arrayable ? $data->toArray() : $data;
    }

    /**
     * Get the evaluated view contents for a named view.
     *
     * @param  string  $view
     * @param  mixed   $data
     * @return \Illuminate\Contracts\View\View
     */
    public function of($view, $data = [])
    {
        return $this->make($this->names[$view], $data);
    }

    /**
     * Register a named view.
     *
     * @param  string  $view
     * @param  string  $name
     * @return void
     */
    public function name($view, $name)
    {
        $this->names[$name] = $view;
    }

    /**
     * Add an alias for a view.
     *
     * @param  string  $view
     * @param  string  $alias
     * @return void
     */
    public function alias($view, $alias)
    {
        $this->aliases[$alias] = $view;
    }

    /**
     * Determine if a given view exists.
     *
     * @param  string  $view
     * @return bool
     */
    public function exists($view)
    {
        try {
            $this->finder->find($view);
        } catch (InvalidArgumentException $e) {
            return false;
        }

        return true;
    }

    /**
     * Get the rendered contents of a partial from a loop.
     *
     * @param  string  $view
     * @param  array   $data
     * @param  string  $iterator
     * @param  string  $empty
     * @return string
     */
    public function renderEach($view, $data, $iterator, $empty = 'raw|')
    {
        $result = '';

        // If is actually data in the array, we will loop through the data and append
        // an instance of the partial view to the final result HTML passing in the
        // iterated value of this data array, allowing the views to access them.
        if (count($data) > 0) {
            foreach ($data as $key => $value) {
                $data = ['key' => $key, $iterator => $value];

                $result .= $this->make($view, $data)->render();
            }
        }

        // If there is no data in the array, we will render the contents of the empty
        // view. Alternatively, the "empty view" could be a raw string that begins
        // with "raw|" for convenience and to let this know that it is a string.
        else {
            if (Str::startsWith($empty, 'raw|')) {
                $result = substr($empty, 4);
            } else {
                $result = $this->make($empty)->render();
            }
        }

        return $result;
    }

    /**
     * Get the appropriate view engine for the given path.
     *
     * @param  string  $path
     * @return \Illuminate\View\Engines\EngineInterface
     *
     * @throws \InvalidArgumentException
     */
    public function getEngineFromPath($path)
    {
        if (! $extension = $this->getExtension($path)) {
            throw new InvalidArgumentException("Unrecognized extension in file: $path");
        }

        $engine = $this->extensions[$extension];

        return $this->engines->resolve($engine);
    }

    /**
     * Get the extension used by the view file.
     *
     * @param  string  $path
     * @return string
     */
    protected function getExtension($path)
    {
        $extensions = array_keys($this->extensions);

        return Arr::first($extensions, function ($value) use ($path) {
            return Str::endsWith($path, '.'.$value);
        });
    }

    /**
     * Add a piece of shared data to the environment.
     *
     * @param  array|string  $key
     * @param  mixed  $value
     * @return mixed
     */
    public function share($key, $value = null)
    {
        $keys = is_array($key) ? $key : [$key => $value];

        foreach ($keys as $key => $value) {
            $this->shared[$key] = $value;
        }

        return $value;
    }

    /**
     * Register a view creator event.
     *
     * @param  array|string     $views
     * @param  \Closure|string  $callback
     * @return array
     */
    public function creator($views, $callback)
    {
        $creators = [];

        foreach ((array) $views as $view) {
            $creators[] = $this->addViewEvent($view, $callback, 'creating: ');
        }

        return $creators;
    }

    /**
     * Register multiple view composers via an array.
     *
     * @param  array  $composers
     * @return array
     */
    public function composers(array $composers)
    {
        $registered = [];

        foreach ($composers as $callback => $views) {
            $registered = array_merge($registered, $this->composer($views, $callback));
        }

        return $registered;
    }

    /**
     * Register a view composer event.
     *
     * @param  array|string  $views
     * @param  \Closure|string  $callback
     * @param  int|null  $priority
     * @return array
     */
    public function composer($views, $callback, $priority = null)
    {
        $composers = [];

        foreach ((array) $views as $view) {
            $composers[] = $this->addViewEvent($view, $callback, 'composing: ', $priority);
        }

        return $composers;
    }

    /**
     * Add an event for a given view.
     *
     * @param  string  $view
     * @param  \Closure|string  $callback
     * @param  string  $prefix
     * @param  int|null  $priority
     * @return \Closure|null
     */
    protected function addViewEvent($view, $callback, $prefix = 'composing: ', $priority = null)
    {
        $view = $this->normalizeName($view);

        if ($callback instanceof Closure) {
            $this->addEventListener($prefix.$view, $callback, $priority);

            return $callback;
        } elseif (is_string($callback)) {
            return $this->addClassEvent($view, $callback, $prefix, $priority);
        }
    }

    /**
     * Register a class based view composer.
     *
     * @param  string    $view
     * @param  string    $class
     * @param  string    $prefix
     * @param  int|null  $priority
     * @return \Closure
     */
    protected function addClassEvent($view, $class, $prefix, $priority = null)
    {
        $name = $prefix.$view;

        // When registering a class based view "composer", we will simply resolve the
        // classes from the application IoC container then call the compose method
        // on the instance. This allows for convenient, testable view composers.
        $callback = $this->buildClassEventCallback($class, $prefix);

        $this->addEventListener($name, $callback, $priority);

        return $callback;
    }

    /**
     * Add a listener to the event dispatcher.
     *
     * @param  string    $name
     * @param  \Closure  $callback
     * @param  int|null  $priority
     * @return void
     */
    protected function addEventListener($name, $callback, $priority = null)
    {
        if (is_null($priority)) {
            $this->events->listen($name, $callback);
        } else {
            $this->events->listen($name, $callback, $priority);
        }
    }

    /**
     * Build a class based container callback Closure.
     *
     * @param  string  $class
     * @param  string  $prefix
     * @return \Closure
     */
    protected function buildClassEventCallback($class, $prefix)
    {
        list($class, $method) = $this->parseClassEvent($class, $prefix);

        // Once we have the class and method name, we can build the Closure to resolve
        // the instance out of the IoC container and call the method on it with the
        // given arguments that are passed to the Closure as the composer's data.
        return function () use ($class, $method) {
            $callable = [$this->container->make($class), $method];

            return call_user_func_array($callable, func_get_args());
        };
    }

    /**
     * Parse a class based composer name.
     *
     * @param  string  $class
     * @param  string  $prefix
     * @return array
     */
    protected function parseClassEvent($class, $prefix)
    {
        if (Str::contains($class, '@')) {
            return explode('@', $class);
        }

        $method = Str::contains($prefix, 'composing') ? 'compose' : 'create';

        return [$class, $method];
    }

    /**
     * Call the composer for a given view.
     *
     * @param  \Illuminate\Contracts\View\View  $view
     * @return void
     */
    public function callComposer(ViewContract $view)
    {
        $this->events->fire('composing: '.$view->name(), [$view]);
    }

    /**
     * Call the creator for a given view.
     *
     * @param  \Illuminate\Contracts\View\View  $view
     * @return void
     */
    public function callCreator(ViewContract $view)
    {
        $this->events->fire('creating: '.$view->name(), [$view]);
    }

    /**
     * Start injecting content into a section.
     *
     * @param  string  $section
     * @param  string  $content
     * @return void
     */
    public function startSection($section, $content = '')
    {
        if ($content === '') {
            if (ob_start()) {
                $this->sectionStack[] = $section;
            }
        } else {
            $this->extendSection($section, $content);
        }
    }

    /**
     * Inject inline content into a section.
     *
     * @param  string  $section
     * @param  string  $content
     * @return void
     */
    public function inject($section, $content)
    {
        return $this->startSection($section, $content);
    }

    /**
     * Stop injecting content into a section and return its contents.
     *
     * @return string
     */
    public function yieldSection()
    {
        if (empty($this->sectionStack)) {
            return '';
        }

        return $this->yieldContent($this->stopSection());
    }

    /**
     * Stop injecting content into a section.
     *
     * @param  bool  $overwrite
     * @return string
     * @throws \InvalidArgumentException
     */
    public function stopSection($overwrite = false)
    {
        if (empty($this->sectionStack)) {
            throw new InvalidArgumentException('Cannot end a section without first starting one.');
        }

        $last = array_pop($this->sectionStack);

        if ($overwrite) {
            $this->sections[$last] = ob_get_clean();
        } else {
            $this->extendSection($last, ob_get_clean());
        }

        return $last;
    }

    /**
     * Stop injecting content into a section and append it.
     *
     * @return string
     * @throws \InvalidArgumentException
     */
    public function appendSection()
    {
        if (empty($this->sectionStack)) {
            throw new InvalidArgumentException('Cannot end a section without first starting one.');
        }

        $last = array_pop($this->sectionStack);

        if (isset($this->sections[$last])) {
            $this->sections[$last] .= ob_get_clean();
        } else {
            $this->sections[$last] = ob_get_clean();
        }

        return $last;
    }

    /**
     * Append content to a given section.
     *
     * @param  string  $section
     * @param  string  $content
     * @return void
     */
    protected function extendSection($section, $content)
    {
        if (isset($this->sections[$section])) {
            $content = str_replace('@parent', $content, $this->sections[$section]);
        }

        $this->sections[$section] = $content;
    }

    /**
     * Get the string contents of a section.
     *
     * @param  string  $section
     * @param  string  $default
     * @return string
     */
    public function yieldContent($section, $default = '')
    {
        $sectionContent = $default;

        if (isset($this->sections[$section])) {
            $sectionContent = $this->sections[$section];
        }

        $sectionContent = str_replace('@@parent', '--parent--holder--', $sectionContent);

        return str_replace(
            '--parent--holder--', '@parent', str_replace('@parent', '', $sectionContent)
        );
    }

    /**
     * Start injecting content into a push section.
     *
     * @param  string  $section
     * @param  string  $content
     * @return void
     */
    public function startPush($section, $content = '')
    {
        if ($content === '') {
            if (ob_start()) {
                $this->pushStack[] = $section;
            }
        } else {
            $this->extendPush($section, $content);
        }
    }

    /**
     * Stop injecting content into a push section.
     *
     * @return string
     * @throws \InvalidArgumentException
     */
    public function stopPush()
    {
        if (empty($this->pushStack)) {
            throw new InvalidArgumentException('Cannot end a section without first starting one.');
        }

        $last = array_pop($this->pushStack);

        $this->extendPush($last, ob_get_clean());

        return $last;
    }

    /**
     * Append content to a given push section.
     *
     * @param  string  $section
     * @param  string  $content
     * @return void
     */
    protected function extendPush($section, $content)
    {
        if (! isset($this->pushes[$section])) {
            $this->pushes[$section] = [];
        }
        if (! isset($this->pushes[$section][$this->renderCount])) {
            $this->pushes[$section][$this->renderCount] = $content;
        } else {
            $this->pushes[$section][$this->renderCount] .= $content;
        }
    }

    /**
     * Get the string contents of a push section.
     *
     * @param  string  $section
     * @param  string  $default
     * @return string
     */
    public function yieldPushContent($section, $default = '')
    {
        if (! isset($this->pushes[$section])) {
            return $default;
        }

        return implode(array_reverse($this->pushes[$section]));
    }

    /**
     * Flush all of the section contents.
     *
     * @return void
     */
    public function flushSections()
    {
        $this->renderCount = 0;

        $this->sections = [];
        $this->sectionStack = [];

        $this->pushes = [];
        $this->pushStack = [];
    }

    /**
     * Flush all of the section contents if done rendering.
     *
     * @return void
     */
    public function flushSectionsIfDoneRendering()
    {
        if ($this->doneRendering()) {
            $this->flushSections();
        }
    }

    /**
     * Increment the rendering counter.
     *
     * @return void
     */
    public function incrementRender()
    {
        $this->renderCount++;
    }

    /**
     * Decrement the rendering counter.
     *
     * @return void
     */
    public function decrementRender()
    {
        $this->renderCount--;
    }

    /**
     * Check if there are no active render operations.
     *
     * @return bool
     */
    public function doneRendering()
    {
        return $this->renderCount == 0;
    }

    /**
     * Add new loop to the stack.
     *
     * @param  \Countable|array  $data
     * @return void
     */
    public function addLoop($data)
    {
        $length = is_array($data) || $data instanceof Countable ? count($data) : null;

        $parent = Arr::last($this->loopsStack);

        $this->loopsStack[] = [
            'iteration' => 0,
            'index' => 0,
            'remaining' => isset($length) ? $length : null,
            'count' => $length,
            'first' => true,
            'last' => isset($length) ? $length == 1 : null,
            'depth' => count($this->loopsStack) + 1,
            'parent' => $parent ? (object) $parent : null,
        ];
    }

    /**
     * Increment the top loop's indices.
     *
     * @return void
     */
    public function incrementLoopIndices()
    {
        $loop = &$this->loopsStack[count($this->loopsStack) - 1];

        $loop['iteration']++;
        $loop['index'] = $loop['iteration'] - 1;

        $loop['first'] = $loop['iteration'] == 1;

        if (isset($loop['count'])) {
            $loop['remaining']--;

            $loop['last'] = $loop['iteration'] == $loop['count'];
        }
    }

    /**
     * Pop a loop from the top of the loop stack.
     *
     * @return void
     */
    public function popLoop()
    {
        array_pop($this->loopsStack);
    }

    /**
     * Get an instance of the first loop in the stack.
     *
     * @return array
     */
    public function getFirstLoop()
    {
        return ($last = Arr::last($this->loopsStack)) ? (object) $last : null;
    }

    /**
     * Get the entire loop stack.
     *
     * @return array
     */
    public function getLoopStack()
    {
        return $this->loopsStack;
    }

    /**
     * Add a location to the array of view locations.
     *
     * @param  string  $location
     * @return void
     */
    public function addLocation($location)
    {
        $this->finder->addLocation($location);
    }

    /**
     * Add a new namespace to the loader.
     *
     * @param  string  $namespace
     * @param  string|array  $hints
     * @return void
     */
    public function addNamespace($namespace, $hints)
    {
        $this->finder->addNamespace($namespace, $hints);
    }

    /**
     * Prepend a new namespace to the loader.
     *
     * @param  string  $namespace
     * @param  string|array  $hints
     * @return void
     */
    public function prependNamespace($namespace, $hints)
    {
        $this->finder->prependNamespace($namespace, $hints);
    }

    /**
     * Register a valid view extension and its engine.
     *
     * @param  string    $extension
     * @param  string    $engine
     * @param  \Closure  $resolver
     * @return void
     */
    public function addExtension($extension, $engine, $resolver = null)
    {
        $this->finder->addExtension($extension);

        if (isset($resolver)) {
            $this->engines->register($engine, $resolver);
        }

        unset($this->extensions[$extension]);

        $this->extensions = array_merge([$extension => $engine], $this->extensions);
    }

    /**
     * Get the extension to engine bindings.
     *
     * @return array
     */
    public function getExtensions()
    {
        return $this->extensions;
    }

    /**
     * Get the engine resolver instance.
     *
     * @return \Illuminate\View\Engines\EngineResolver
     */
    public function getEngineResolver()
    {
        return $this->engines;
    }

    /**
     * Get the view finder instance.
     *
     * @return \Illuminate\View\ViewFinderInterface
     */
    public function getFinder()
    {
        return $this->finder;
    }

    /**
     * Set the view finder instance.
     *
     * @param  \Illuminate\View\ViewFinderInterface  $finder
     * @return void
     */
    public function setFinder(ViewFinderInterface $finder)
    {
        $this->finder = $finder;
    }

    /**
     * Get the event dispatcher instance.
     *
     * @return \Illuminate\Contracts\Events\Dispatcher
     */
    public function getDispatcher()
    {
        return $this->events;
    }

    /**
     * Set the event dispatcher instance.
     *
     * @param  \Illuminate\Contracts\Events\Dispatcher  $events
     * @return void
     */
    public function setDispatcher(Dispatcher $events)
    {
        $this->events = $events;
    }

    /**
     * Get the IoC container instance.
     *
     * @return \Illuminate\Contracts\Container\Container
     */
    public function getContainer()
    {
        return $this->container;
    }

    /**
     * Set the IoC container instance.
     *
     * @param  \Illuminate\Contracts\Container\Container  $container
     * @return void
     */
    public function setContainer(Container $container)
    {
        $this->container = $container;
    }

    /**
     * Get an item from the shared data.
     *
     * @param  string  $key
     * @param  mixed   $default
     * @return mixed
     */
    public function shared($key, $default = null)
    {
        return Arr::get($this->shared, $key, $default);
    }

    /**
     * Get all of the shared data for the environment.
     *
     * @return array
     */
    public function getShared()
    {
        return $this->shared;
    }

    /**
     * Check if section exists.
     *
     * @param  string  $name
     * @return bool
     */
    public function hasSection($name)
    {
        return array_key_exists($name, $this->sections);
    }

    /**
     * Get the entire array of sections.
     *
     * @return array
     */
    public function getSections()
    {
        return $this->sections;
    }

    /**
     * Get all of the registered named views in environment.
     *
     * @return array
     */
    public function getNames()
    {
        return $this->names;
    }
}
