////
/// @group site.config
////

@use 'strings.scss' as *;
@use 'collections.scss' as *;
@use 'flatmap.scss' as *;
@use 'units.scss' as *;

// Global map that contains all config settings for the site (private)
$-config: ();

// Global map that contains all default config settings for the site (private)
$-defaults: ();

@function get-config-map() {
    @return $-config;
}

/// Retrieve a configuration setting.
///
/// @param {string or list} $paths The path (string) list of paths (list) where the setting should
/// be found. Each path is one or more keys separated by colons (e.g. 'colors:accent' would find the
/// value accent in the colors map). If a list of strings is provided, they will searched in order
/// and the first non-null value will be returned.
///
/// @param {*} $fallback [null] The value to return if the path doesn't exist.
///
/// @param {*} $throw-not-found [null] Whether to throw an errow if the value can't be retrieved
///
/// @example
/// $value: get('colors:mycolor', red);

@function get($paths, $fallback: null, $throw-not-found: true) {
    // $paths is a list
    @if (type-of($paths) == 'list') {
        @each $path in $paths {
            $result: get($path, null);
            @if ($result != null) {
                @return $result;
            }
        }
    } @else {
        $result: flat-get($-config, $paths, $fallback);
        @if ($result != null) {
            @return $result;
        }
    }

    @if ($throw-not-found) {
        $path-str: if(type-of($paths) == 'list', list-join($paths, ':'), $paths);
        @error 'Could not find required config value for path "#{$path-str}". This could mean that pxstyles wasn\'t properly configured using the init() mixin. If you are seeing this error during a call to config, then you are likely using a function that requires configuration. You can fix this by also configuring the missing value.';
    }

    @return $fallback;
}

/// Retrieve a configuration setting if and only if the provided $value is null.
///
/// @param {string or list} $paths The value to check for null
/// @param {string or list} $paths Path for the value to retrieve if $value is null (see details for get())
/// @param {*} $throw-not-found [null] Whether to throw an errow if the value can't be retrieved
///
/// @example
/// $value: if-null-get(null, 'colors:mycolor'); // => the config value for 'colors:mycolor'
///
/// @example
/// $value: if-null-get(red, 'colors:mycolor'); // => red

@function if-null-get($value, $paths, $throw-not-found: true) {
    @return if-null($value, get($paths, $throw-not-found: $throw-not));
}

/// Add a configuration setting.
///
/// @param {*} $path The path of the setting with keys separated by colons (e.g.
/// 'colors:accent' would set the value accent in the colors map).
///
/// @param {*} $val [null] The value to be added.

@mixin config($path, $val) {
    $-config: flat-set($-config, $path, $val) !global;
}

/// Add a default configuration setting (provides the same functionality as config, but will not
/// overwrite an existing setting).
///
/// @param {*} $path The path of the setting with keys separated by colons (e.g. 'colors:accent'
/// would set the value accent in the colors map).
///
/// @param {*} $val [null] The value to be added.

@mixin default($path, $val) {
    $current: get($path, $fallback: 'NOTFOUND');

    // if the value is not found, then we can just write it
    @if ($current == 'NOTFOUND') {
        @include config($path, $val);
    }

    // if the value exists and is a map then we do deep merge
    @else {
        @if (is-map($current) and is-map($val)) {
            $merge: flat-merge($val, $current);
            @include config($path, flat-merge($val, $current));
        }
    }
}