1 files changed, 154 insertions, 0 deletions
diff --git a/intl/l10n/rust/fluent-ffi/src/ffi.rs b/intl/l10n/rust/fluent-ffi/src/ffi.rs
new file mode 100644
index 0000000000..a264ad11b7
--- /dev/null
+++ b/intl/l10n/rust/fluent-ffi/src/ffi.rs
@@ -0,0 +1,154 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+use crate::builtins::FluentDateTimeOptions;
+use fluent::types::FluentNumberCurrencyDisplayStyle;
+use fluent::types::FluentNumberOptions;
+use fluent::types::FluentNumberStyle;
+use nsstring::nsCString;
+
+pub enum RawNumberFormatter {}
+
+#[repr(C)]
+pub enum FluentNumberStyleRaw {
+    Decimal,
+    Currency,
+    Percent,
+}
+
+impl From<FluentNumberStyle> for FluentNumberStyleRaw {
+    fn from(input: FluentNumberStyle) -> Self {
+        match input {
+            FluentNumberStyle::Decimal => Self::Decimal,
+            FluentNumberStyle::Currency => Self::Currency,
+            FluentNumberStyle::Percent => Self::Percent,
+        }
+    }
+}
+
+#[repr(C)]
+#[derive(Clone, Copy)]
+pub enum FluentNumberCurrencyDisplayStyleRaw {
+    Symbol,
+    Code,
+    Name,
+}
+
+impl From<FluentNumberCurrencyDisplayStyle> for FluentNumberCurrencyDisplayStyleRaw {
+    fn from(input: FluentNumberCurrencyDisplayStyle) -> Self {
+        match input {
+            FluentNumberCurrencyDisplayStyle::Symbol => Self::Symbol,
+            FluentNumberCurrencyDisplayStyle::Code => Self::Code,
+            FluentNumberCurrencyDisplayStyle::Name => Self::Name,
+        }
+    }
+}
+
+#[repr(C)]
+pub struct FluentNumberOptionsRaw {
+    pub style: FluentNumberStyleRaw,
+    pub currency: nsCString,
+    pub currency_display: FluentNumberCurrencyDisplayStyleRaw,
+    pub use_grouping: bool,
+    pub minimum_integer_digits: usize,
+    pub minimum_fraction_digits: usize,
+    pub maximum_fraction_digits: usize,
+    pub minimum_significant_digits: isize,
+    pub maximum_significant_digits: isize,
+}
+
+fn get_number_option(val: Option<usize>, min: usize, max: usize, default: usize) -> usize {
+    if let Some(val) = val {
+        if val >= min && val <= max {
+            val
+        } else {
+            default
+        }
+    } else {
+        default
+    }
+}
+
+impl From<&FluentNumberOptions> for FluentNumberOptionsRaw {
+    fn from(input: &FluentNumberOptions) -> Self {
+        let currency: nsCString = if let Some(ref currency) = input.currency {
+            currency.into()
+        } else {
+            nsCString::new()
+        };
+
+        //XXX: This should be fetched from currency table.
+        let currency_digits = 2;
+
+        // Keep it aligned with ECMA402 NumberFormat logic.
+        let minfd_default = if input.style == FluentNumberStyle::Currency {
+            currency_digits
+        } else {
+            0
+        };
+        let maxfd_default = match input.style {
+            FluentNumberStyle::Decimal => 3,
+            FluentNumberStyle::Currency => currency_digits,
+            FluentNumberStyle::Percent => 0,
+        };
+        let minid = get_number_option(input.minimum_integer_digits, 1, 21, 1);
+        let minfd = get_number_option(input.minimum_fraction_digits, 0, 20, minfd_default);
+        let maxfd_actual_default = std::cmp::max(minfd, maxfd_default);
+        let maxfd = get_number_option(
+            input.maximum_fraction_digits,
+            minfd,
+            20,
+            maxfd_actual_default,
+        );
+
+        let (minsd, maxsd) = if input.minimum_significant_digits.is_some()
+            || input.maximum_significant_digits.is_some()
+        {
+            let minsd = get_number_option(input.minimum_significant_digits, 1, 21, 1);
+            let maxsd = get_number_option(input.maximum_significant_digits, minsd, 21, 21);
+            (minsd as isize, maxsd as isize)
+        } else {
+            (-1, -1)
+        };
+
+        Self {
+            style: input.style.into(),
+            currency,
+            currency_display: input.currency_display.into(),
+            use_grouping: input.use_grouping,
+            minimum_integer_digits: minid,
+            minimum_fraction_digits: minfd,
+            maximum_fraction_digits: maxfd,
+            minimum_significant_digits: minsd,
+            maximum_significant_digits: maxsd,
+        }
+    }
+}
+
+pub enum RawDateTimeFormatter {}
+
+extern "C" {
+    pub fn FluentBuiltInNumberFormatterCreate(
+        locale: &nsCString,
+        options: &FluentNumberOptionsRaw,
+    ) -> *mut RawNumberFormatter;
+    pub fn FluentBuiltInNumberFormatterFormat(
+        formatter: *const RawNumberFormatter,
+        input: f64,
+        out_count: &mut usize,
+        out_capacity: &mut usize,
+    ) -> *mut u8;
+    pub fn FluentBuiltInNumberFormatterDestroy(formatter: *mut RawNumberFormatter);
+
+    pub fn FluentBuiltInDateTimeFormatterCreate(
+        locale: &nsCString,
+        options: FluentDateTimeOptions,
+    ) -> *mut RawDateTimeFormatter;
+    pub fn FluentBuiltInDateTimeFormatterFormat(
+        formatter: *const RawDateTimeFormatter,
+        input: f64,
+        out_count: &mut u32,
+    ) -> *mut u8;
+    pub fn FluentBuiltInDateTimeFormatterDestroy(formatter: *mut RawDateTimeFormatter);
+}