//! Hardware configuration and timing constants for the CMDR Keyboard 42.

/// External crystal frequency (Hz).
pub const XTAL_FREQ_HZ: u32 = 12_000_000;

/// Debounce scans required before a key state toggles.
pub const MATRIX_DEBOUNCE_SCANS_PRESS: u8 = 2;
pub const MATRIX_DEBOUNCE_SCANS_RELEASE: u8 = 3;

/// Initial scan iterations before trusting key state.
pub const INITIAL_SCAN_PASSES: usize = 50;

/// Button matrix geometry.
pub const KEY_ROWS: usize = 4;
pub const KEY_COLS: usize = 12;
pub const NUMBER_OF_KEYS: usize = KEY_ROWS * KEY_COLS;

/// USB identification constants.
pub mod usb {
    pub const VID: u16 = 0x1209;
    pub const PID: u16 = 0x0001;
    pub const MANUFACTURER: &str = "CMtec";
    pub const PRODUCT: &str = "CMDR Keyboard 42";
    pub const SERIAL_NUMBER: &str = "0001";
}

/// Timing cadence helpers used throughout the firmware.
pub mod timers {
    pub const USB_REPORT_INTERVAL_MS: u32 = 10;
    pub const USB_TICK_INTERVAL_US: u32 = 250;
    pub const STATUS_LED_INTERVAL_MS: u32 = 4;
    pub const IDLE_TIMEOUT_MS: u32 = 5_000;
}

/// Physical GPIO assignments for the RP2040.
pub mod pins {
    pub const BUTTON_ROW_0: u8 = 0;
    pub const BUTTON_ROW_1: u8 = 1;
    pub const BUTTON_ROW_2: u8 = 29;
    pub const BUTTON_ROW_3: u8 = 28;

    pub const BUTTON_COL_0: u8 = 12;
    pub const BUTTON_COL_1: u8 = 13;
    pub const BUTTON_COL_2: u8 = 14;
    pub const BUTTON_COL_3: u8 = 15;
    pub const BUTTON_COL_4: u8 = 26;
    pub const BUTTON_COL_5: u8 = 27;
    pub const BUTTON_COL_6: u8 = 7;
    pub const BUTTON_COL_7: u8 = 8;
    pub const BUTTON_COL_8: u8 = 6;
    pub const BUTTON_COL_9: u8 = 9;
    pub const BUTTON_COL_10: u8 = 10;
    pub const BUTTON_COL_11: u8 = 11;

    pub const STATUS_LED: u8 = 16;
}

/// Convenience macro mirroring the joystick repository for fetching typed pins.
#[macro_export]
macro_rules! get_pin {
    ($pins:expr, button_row_0) => {{
        const _: u8 = $crate::hardware::pins::BUTTON_ROW_0;
        $pins.gpio0
    }};
    ($pins:expr, button_row_1) => {{
        const _: u8 = $crate::hardware::pins::BUTTON_ROW_1;
        $pins.gpio1
    }};
    ($pins:expr, button_row_2) => {{
        const _: u8 = $crate::hardware::pins::BUTTON_ROW_2;
        $pins.gpio29
    }};
    ($pins:expr, button_row_3) => {{
        const _: u8 = $crate::hardware::pins::BUTTON_ROW_3;
        $pins.gpio28
    }};
    ($pins:expr, button_col_0) => {{
        const _: u8 = $crate::hardware::pins::BUTTON_COL_0;
        $pins.gpio12
    }};
    ($pins:expr, button_col_1) => {{
        const _: u8 = $crate::hardware::pins::BUTTON_COL_1;
        $pins.gpio13
    }};
    ($pins:expr, button_col_2) => {{
        const _: u8 = $crate::hardware::pins::BUTTON_COL_2;
        $pins.gpio14
    }};
    ($pins:expr, button_col_3) => {{
        const _: u8 = $crate::hardware::pins::BUTTON_COL_3;
        $pins.gpio15
    }};
    ($pins:expr, button_col_4) => {{
        const _: u8 = $crate::hardware::pins::BUTTON_COL_4;
        $pins.gpio26
    }};
    ($pins:expr, button_col_5) => {{
        const _: u8 = $crate::hardware::pins::BUTTON_COL_5;
        $pins.gpio27
    }};
    ($pins:expr, button_col_6) => {{
        const _: u8 = $crate::hardware::pins::BUTTON_COL_6;
        $pins.gpio7
    }};
    ($pins:expr, button_col_7) => {{
        const _: u8 = $crate::hardware::pins::BUTTON_COL_7;
        $pins.gpio8
    }};
    ($pins:expr, button_col_8) => {{
        const _: u8 = $crate::hardware::pins::BUTTON_COL_8;
        $pins.gpio6
    }};
    ($pins:expr, button_col_9) => {{
        const _: u8 = $crate::hardware::pins::BUTTON_COL_9;
        $pins.gpio9
    }};
    ($pins:expr, button_col_10) => {{
        const _: u8 = $crate::hardware::pins::BUTTON_COL_10;
        $pins.gpio10
    }};
    ($pins:expr, button_col_11) => {{
        const _: u8 = $crate::hardware::pins::BUTTON_COL_11;
        $pins.gpio11
    }};
    ($pins:expr, status_led) => {{
        const _: u8 = $crate::hardware::pins::STATUS_LED;
        $pins.gpio16
    }};
}

#[cfg(all(test, feature = "std"))]
mod tests {
    use super::*;

    #[test]
    fn number_of_keys_matches_rows_and_cols() {
        assert_eq!(NUMBER_OF_KEYS, KEY_ROWS * KEY_COLS);
    }

    #[test]
    fn usb_metadata_is_consistent() {
        assert_ne!(usb::VID, 0);
        assert_ne!(usb::PID, 0);
        assert!(!usb::MANUFACTURER.is_empty());
        assert!(!usb::PRODUCT.is_empty());
    }
}