ql.rs/src/macros.rs

use paste;

#[doc(hidden)]
#[macro_export]
macro_rules! query_def_type {
    (@ ($type:ty)) => {
        $type
    };
    (@ 'dyn ($type:ty)) => {
        $type
    };
    (@ 'vec ($type:ty)) => {
        ::std::vec::Vec<$type>
    };
    (@ 'map ($key:ty, $value:ty)) => {
        ::std::collections::HashMap<$key, $value>
    };
}

#[doc(hidden)]
#[macro_export]
macro_rules! query_def_field {
    (@dyn $type:ty) => {
        Option<<$type as $crate::DynamicQuery>::Definition>
    };
    (@ ($type:ty)) => {
        bool
    };
    (@ 'dyn ($type:ty)) => {
        $crate::query_def_field!(@dyn $type)
    };
    (@ 'vec ($type:ty)) => {
        $crate::query_def_field!(@dyn $type)
    };
    (@ 'map ($key:ty, $value:ty)) => {
        $crate::query_def_field!(@dyn $value)
    };
}

#[doc(hidden)]
#[macro_export]
macro_rules! query_def_filter {
    // note about this: 'dyn is implied for 'vec and 'map because if the type is not 'dyn, then the
    // special handling is not necessary in the first place.
    (@ $query:expr, $value:ident, 'vec ($_type:path)) => {
        match $query {
            Some(query) => {
                if let Some(ref mut value) = $value {
                    for value in value.iter_mut() {
                        value.filter_ref(&query);
                    }
                }
            }
            None => {
                *$value = None;
            }
        }
    };
    (@ $query:expr, $value:ident, 'map ($_key:path, $_value:path)) => {
        match $query {
            Some(query) => {
                if let Some(ref mut value) = $value {
                    for (_, value) in value.iter_mut() {
                        value.filter_ref(&query);
                    }
                }
            }
            None => {
                *$value = None;
            }
        }
    };
    (@ $query:expr, $value:ident, 'dyn ($($_type:tt)+)) => {
        if let Some(ref mut value) = $value {
            if let Some(ref query) = $query {
                value.filter_ref(&query);
            }
        }
    };
    (@ $query:expr, $value:ident, ($($_type:tt)+)) => {
        if !*$query {
            *$value = None;
        }
    };
}

#[doc(hidden)]
#[macro_export]
macro_rules! query_def_internal_struct {
    (@
        $(
            $(#[$meta:meta])
            *
            $vis:vis $data:ident$((
                $(#[$def_meta:meta])
                +
            ))? {
                $(
                    $(#[$field_meta:meta])
                    *
                    $field:ident: $($qualifier:lifetime)? ($($type:tt)+),
                )+
            }
        )
        *
    ) => {
        $(
            #[derive(Debug, Clone)]
            $(#[$meta])
            *
            $vis struct $data {
                $(
                    $(#[$field_meta])
                    *
                    pub $field: Option<$crate::query_def_type!(@ $($qualifier)? ($($type)+))>,
                )+
            }

            $crate::paste::paste! {
                #[derive(Debug, Clone, Copy, Default)]
                $( $( #[$def_meta] )+ )?
                $vis struct [<$data Def>] {
                    $(
                        pub $field: $crate::query_def_field!(@ $($qualifier)? ($($type)+)),
                    )+
                }
            }

            impl $crate::DynamicQuery for $data {
                type Definition = $crate::paste::paste! { [<$data Def>] };

                fn filter_ref(&mut self, def: &Self::Definition) {
                    $(
                        let query = &def.$field;
                        let value = &mut self.$field;
                        $crate::query_def_filter!(@ query, value, $($qualifier)? ($($type)+));
                    )
                    +
                }
            }
        )
        *
    };
}

#[doc(hidden)]
#[macro_export]
macro_rules! query_def_internal_enum {
    (@
        $(
            $(#[$meta:meta])
            *
            $vis:vis $data:ident$((
                $(#[$def_meta:meta])
                +
            ))? {
                $(
                    $( #[$variant_meta:meta] )*
                    $variant:ident$((
                        $(#[$variant_def_meta:meta])
                        +
                    ))? {
                        $(
                            $(#[$field_meta:meta])
                            *
                            $field:ident: $($qualifier:lifetime)? ($($type:tt)+),
                        )+
                    }
                ),+
            }
        )
        *
    ) => {
        $(
            #[derive(Debug, Clone)]
            $(#[$meta])
            *
            $vis enum $data {
                $(
                    $( #[$variant_meta] )*
                    $variant {
                        $(
                            $(#[$field_meta])
                            *
                            $field: Option<$crate::query_def_type!(@ $($qualifier)? ($($type)+))>,
                        )+
                    }
                ),+
            }

            $crate::paste::paste! {
                #[derive(Debug, Clone, Copy, Default)]
                $( $( #[$def_meta] )+ )?
                $vis struct [<$data Def>] {
                    $(
                        pub [<$variant:snake:lower>]: [<$data Def Variant $variant>],
                    )+
                }
            }

            $crate::paste::paste! {
//                impl [<$data Def>] {
//                    $(
//                        pub type $variant = [<$data Def Variant $variant>];
//                    )+
//                }

                $(
                    #[derive(Debug, Clone, Copy, Default)]
                    $( $( #[$variant_def_meta] )+ )?
                    $vis struct [<$data Def Variant $variant>] {
                        $(
                            pub $field: $crate::query_def_field!(@ $($qualifier)? ($($type)+)),
                        )+
                    }
                )+
            }

            impl $crate::DynamicQuery for $data {
                type Definition = $crate::paste::paste! { [<$data Def>] };

                fn filter_ref(&mut self, def: &Self::Definition) {
                    match self {
                        $(
                            Self::$variant { $( ref mut $field ),+ } => {
                                let def = $crate::paste::paste! { &def.[<$variant:snake:lower>] };
                                $(
                                    let query = &def.$field;
                                    $crate::query_def_filter!(@ query, $field, $($qualifier)? ($($type)+));
                                )
                                +
                            }
                        )+
                    }
                }
            }
        )
        *
    };
}

/// Defines a dynamic query structure.
#[cfg(not(feature = "serde"))]
#[macro_export]
macro_rules! query_def_struct {
    (
        $(
            $(#[$meta:meta])
            *
            $vis:vis $data:ident$((
                $(#[$def_meta:meta])
                +
            ))? {
                $(
                    $(#[$field_meta:meta])
                    *
                    $field:ident: $($qualifier:lifetime)? ($($type:tt)+),
                )+
            }
        )
        *
    ) => {
        $crate::query_def_internal_struct!(@
        $(
            $(#[$meta])
            *
            $vis $data$((
                $(#[$def_meta])
                +
            ))? {
                $(
                    $(#[$field_meta])
                    *
                    $field: $($qualifier)? ($($type)+),
                )+
            }
        )
        *
        );
    };
}

/// Defines a dynamic enumerated query structure.
#[cfg(not(feature = "serde"))]
#[macro_export]
macro_rules! query_def_enum {
    (
        $(
            $(#[$meta:meta])
            *
            $vis:vis $data:ident$((
                $(#[$def_meta:meta])
                +
            ))? {
                $(
                    $(#[$variant_meta:meta])
                    *
                    $variant:ident$((
                        $(#[$variant_def_meta:meta])
                        +
                    ))? {
                        $(
                            $(#[$field_meta:meta])
                            *
                            $field:ident: $($qualifier:lifetime)? ($($type:tt)+),
                        )+
                    }
                ),+
            }
        )
        *
    ) => {
        $crate::query_def_internal_enum!(@
        $(
            $(#[$meta])
            *
            $vis $data$((
                $(#[$def_meta])
                +
            ))? {
                $(
                    $(#[$variant_meta])
                    *
                    $variant$((
                        $(#[$variant_def_meta])
                        ?
                    ))? {
                        $(
                            $(#[$field_meta])
                            *
                            $field: $($qualifier)? ($($type)+),
                        )+
                    }
                ),+
            }
        )
        *
        );
    };
}

/// Defines a dynamic query structure.
#[cfg(feature = "serde")]
#[macro_export]
macro_rules! query_def_struct {
    (
        $(
            $(#[$meta:meta])
            *
            $vis:vis $data:ident$((
                $(#[$def_meta:meta])
                +
            ))? {
                $(
                    $(#[$field_meta:meta])
                    *
                    $field:ident: $($qualifier:lifetime)? ($($type:tt)+),
                )+
            }
        )
        *
    ) => {
        $crate::query_def_internal_struct!(@
        $(
            #[derive(Serialize, Deserialize)]
            $(#[$meta])
            *
            $vis $data(
                #[derive(Serialize, Deserialize)]
                #[serde(default)]
                $(
                $(#[$def_meta])
                +
                )?
            ) {
                $(
                    #[serde(skip_serializing_if = "Option::is_none")]
                    $(#[$field_meta])
                    *
                    $field: $($qualifier)? ($($type)+),
                )+
            }
        )
        *
        );
    };
}

/// Defines a dynamic enumerated query structure.
#[cfg(feature = "serde")]
#[macro_export]
macro_rules! query_def_enum {
    (
        $(
            $(#[$meta:meta])
            *
            $vis:vis $data:ident$((
                $(#[$def_meta:meta])
                +
            ))? {
                $(
                    $(#[$variant_meta:meta])
                    *
                    $variant:ident$((
                        $(#[$variant_def_meta:meta])
                        +
                    ))? {
                        $(
                            $(#[$field_meta:meta])
                            *
                            $field:ident: $($qualifier:lifetime)? ($($type:tt)+),
                        )+
                    }
                ),+
            }
        )
        *
    ) => {
        $crate::query_def_internal_enum!(@
        $(
            #[derive(Serialize, Deserialize)]
            $(#[$meta])
            *
            $vis $data(
                #[derive(Serialize, Deserialize)]
                #[serde(default)]
                $(
                $(#[$def_meta])
                +
                )?
            ) {
                $(
                    $(#[$variant_meta])
                    *
                    $variant(
                        #[derive(Serialize, Deserialize)]
                        #[serde(default)]
                        $(
                        $(#[$variant_def_meta])
                        +
                        )?
                    ) {
                        $(
                            #[serde(skip_serializing_if = "Option::is_none")]
                            $(#[$field_meta])
                            *
                            $field: $($qualifier)? ($($type)+),
                        )+
                    }
                ),+
            }
        )
        *
        );
    };
}