mod traits;

use core::marker::PhantomData;

use embassy_hal_internal::{into_ref, PeripheralRef};

#[allow(unused_imports)]
use crate::gpio::sealed::{AFType, Pin};
use crate::gpio::AnyPin;
use crate::hrtim::traits::Instance;
use crate::time::Hertz;
use crate::Peripheral;

pub enum Source {
    Master,
    ChA,
    ChB,
    ChC,
    ChD,
    ChE,
}

pub struct BurstController<T: Instance> {
    phantom: PhantomData<T>,
}
pub struct Master<T: Instance> {
    phantom: PhantomData<T>,
}
pub struct ChA<T: Instance> {
    phantom: PhantomData<T>,
}
pub struct ChB<T: Instance> {
    phantom: PhantomData<T>,
}
pub struct ChC<T: Instance> {
    phantom: PhantomData<T>,
}
pub struct ChD<T: Instance> {
    phantom: PhantomData<T>,
}
pub struct ChE<T: Instance> {
    phantom: PhantomData<T>,
}

mod sealed {
    use super::Instance;

    pub trait AdvancedChannel<T: Instance> {
        fn raw() -> usize;
    }
}

pub trait AdvancedChannel<T: Instance>: sealed::AdvancedChannel<T> {}

pub struct PwmPin<'d, Perip, Channel> {
    _pin: PeripheralRef<'d, AnyPin>,
    phantom: PhantomData<(Perip, Channel)>,
}

pub struct ComplementaryPwmPin<'d, Perip, Channel> {
    _pin: PeripheralRef<'d, AnyPin>,
    phantom: PhantomData<(Perip, Channel)>,
}

macro_rules! advanced_channel_impl {
    ($new_chx:ident, $channel:tt, $ch_num:expr, $pin_trait:ident, $complementary_pin_trait:ident) => {
        impl<'d, Perip: Instance> PwmPin<'d, Perip, $channel<Perip>> {
            pub fn $new_chx(pin: impl Peripheral<P = impl $pin_trait<Perip>> + 'd) -> Self {
                into_ref!(pin);
                critical_section::with(|_| {
                    pin.set_low();
                    pin.set_as_af(pin.af_num(), AFType::OutputPushPull);
                    #[cfg(gpio_v2)]
                    pin.set_speed(crate::gpio::Speed::VeryHigh);
                });
                PwmPin {
                    _pin: pin.map_into(),
                    phantom: PhantomData,
                }
            }
        }

        impl<'d, Perip: Instance> ComplementaryPwmPin<'d, Perip, $channel<Perip>> {
            pub fn $new_chx(pin: impl Peripheral<P = impl $complementary_pin_trait<Perip>> + 'd) -> Self {
                into_ref!(pin);
                critical_section::with(|_| {
                    pin.set_low();
                    pin.set_as_af(pin.af_num(), AFType::OutputPushPull);
                    #[cfg(gpio_v2)]
                    pin.set_speed(crate::gpio::Speed::VeryHigh);
                });
                ComplementaryPwmPin {
                    _pin: pin.map_into(),
                    phantom: PhantomData,
                }
            }
        }

        impl<T: Instance> sealed::AdvancedChannel<T> for $channel<T> {
            fn raw() -> usize {
                $ch_num
            }
        }
        impl<T: Instance> AdvancedChannel<T> for $channel<T> {}
    };
}

advanced_channel_impl!(new_cha, ChA, 0, ChannelAPin, ChannelAComplementaryPin);
advanced_channel_impl!(new_chb, ChB, 1, ChannelBPin, ChannelBComplementaryPin);
advanced_channel_impl!(new_chc, ChC, 2, ChannelCPin, ChannelCComplementaryPin);
advanced_channel_impl!(new_chd, ChD, 3, ChannelDPin, ChannelDComplementaryPin);
advanced_channel_impl!(new_che, ChE, 4, ChannelEPin, ChannelEComplementaryPin);

/// Struct used to divide a high resolution timer into multiple channels
pub struct AdvancedPwm<'d, T: Instance> {
    _inner: PeripheralRef<'d, T>,
    pub master: Master<T>,
    pub burst_controller: BurstController<T>,
    pub ch_a: ChA<T>,
    pub ch_b: ChB<T>,
    pub ch_c: ChC<T>,
    pub ch_d: ChD<T>,
    pub ch_e: ChE<T>,
}

impl<'d, T: Instance> AdvancedPwm<'d, T> {
    pub fn new(
        tim: impl Peripheral<P = T> + 'd,
        _cha: Option<PwmPin<'d, T, ChA<T>>>,
        _chan: Option<ComplementaryPwmPin<'d, T, ChA<T>>>,
        _chb: Option<PwmPin<'d, T, ChB<T>>>,
        _chbn: Option<ComplementaryPwmPin<'d, T, ChB<T>>>,
        _chc: Option<PwmPin<'d, T, ChC<T>>>,
        _chcn: Option<ComplementaryPwmPin<'d, T, ChC<T>>>,
        _chd: Option<PwmPin<'d, T, ChD<T>>>,
        _chdn: Option<ComplementaryPwmPin<'d, T, ChD<T>>>,
        _che: Option<PwmPin<'d, T, ChE<T>>>,
        _chen: Option<ComplementaryPwmPin<'d, T, ChE<T>>>,
    ) -> Self {
        Self::new_inner(tim)
    }

    fn new_inner(tim: impl Peripheral<P = T> + 'd) -> Self {
        into_ref!(tim);

        T::enable();
        <T as crate::rcc::sealed::RccPeripheral>::reset();

        //        // Enable and and stabilize the DLL
        //        T::regs().dllcr().modify(|w| {
        //            // w.set_calen(true);
        //            // w.set_calrte(11);
        //            w.set_cal(true);
        //        });
        //
        //        debug!("wait for dll calibration");
        //        while !T::regs().isr().read().dllrdy() {}
        //
        //        debug!("dll calibration complete");

        Self {
            _inner: tim,
            master: Master { phantom: PhantomData },
            burst_controller: BurstController { phantom: PhantomData },
            ch_a: ChA { phantom: PhantomData },
            ch_b: ChB { phantom: PhantomData },
            ch_c: ChC { phantom: PhantomData },
            ch_d: ChD { phantom: PhantomData },
            ch_e: ChE { phantom: PhantomData },
        }
    }
}

impl<T: Instance> BurstController<T> {
    pub fn set_source(&mut self, _source: Source) {
        todo!("burst mode control registers not implemented")
    }
}

/// Represents a fixed-frequency bridge converter
///
/// Our implementation of the bridge converter uses a single channel and three compare registers,
/// allowing implementation of a synchronous buck or boost converter in continuous or discontinuous
/// conduction mode.
///
/// It is important to remember that in synchronous topologies, energy can flow in reverse during
/// light loading conditions, and that the low-side switch must be active for a short time to drive
/// a bootstrapped high-side switch.
pub struct BridgeConverter<T: Instance, C: AdvancedChannel<T>> {
    timer: PhantomData<T>,
    channel: PhantomData<C>,
    dead_time: u16,
    primary_duty: u16,
    min_secondary_duty: u16,
    max_secondary_duty: u16,
}

impl<T: Instance, C: AdvancedChannel<T>> BridgeConverter<T, C> {
    pub fn new(_channel: C, frequency: Hertz) -> Self {
        use crate::pac::hrtim::vals::{Activeeffect, Inactiveeffect};

        T::set_channel_frequency(C::raw(), frequency);

        // Always enable preload
        T::regs().tim(C::raw()).cr().modify(|w| {
            w.set_preen(true);
            w.set_repu(true);
            w.set_cont(true);
        });

        // Enable timer outputs
        T::regs().oenr().modify(|w| {
            w.set_t1oen(C::raw(), true);
            w.set_t2oen(C::raw(), true);
        });

        // The dead-time generation unit cannot be used because it forces the other output
        // to be completely complementary to the first output, which restricts certain waveforms
        // Therefore, software-implemented dead time must be used when setting the duty cycles

        // Set output 1 to active on a period event
        T::regs()
            .tim(C::raw())
            .setr(0)
            .modify(|w| w.set_per(Activeeffect::SETACTIVE));

        // Set output 1 to inactive on a compare 1 event
        T::regs()
            .tim(C::raw())
            .rstr(0)
            .modify(|w| w.set_cmp(0, Inactiveeffect::SETINACTIVE));

        // Set output 2 to active on a compare 2 event
        T::regs()
            .tim(C::raw())
            .setr(1)
            .modify(|w| w.set_cmp(1, Activeeffect::SETACTIVE));

        // Set output 2 to inactive on a compare 3 event
        T::regs()
            .tim(C::raw())
            .rstr(1)
            .modify(|w| w.set_cmp(2, Inactiveeffect::SETINACTIVE));

        Self {
            timer: PhantomData,
            channel: PhantomData,
            dead_time: 0,
            primary_duty: 0,
            min_secondary_duty: 0,
            max_secondary_duty: 0,
        }
    }

    pub fn start(&mut self) {
        T::regs().mcr().modify(|w| w.set_tcen(C::raw(), true));
    }

    pub fn stop(&mut self) {
        T::regs().mcr().modify(|w| w.set_tcen(C::raw(), false));
    }

    pub fn enable_burst_mode(&mut self) {
        T::regs().tim(C::raw()).outr().modify(|w| {
            // Enable Burst Mode
            w.set_idlem(0, true);
            w.set_idlem(1, true);

            // Set output to active during the burst
            w.set_idles(0, true);
            w.set_idles(1, true);
        })
    }

    pub fn disable_burst_mode(&mut self) {
        T::regs().tim(C::raw()).outr().modify(|w| {
            // Disable Burst Mode
            w.set_idlem(0, false);
            w.set_idlem(1, false);
        })
    }

    fn update_primary_duty_or_dead_time(&mut self) {
        self.min_secondary_duty = self.primary_duty + self.dead_time;

        T::regs().tim(C::raw()).cmp(0).modify(|w| w.set_cmp(self.primary_duty));
        T::regs()
            .tim(C::raw())
            .cmp(1)
            .modify(|w| w.set_cmp(self.min_secondary_duty));
    }

    /// Set the dead time as a proportion of the maximum compare value
    pub fn set_dead_time(&mut self, dead_time: u16) {
        self.dead_time = dead_time;
        self.max_secondary_duty = self.get_max_compare_value() - dead_time;
        self.update_primary_duty_or_dead_time();
    }

    /// Get the maximum compare value of a duty cycle
    pub fn get_max_compare_value(&mut self) -> u16 {
        T::regs().tim(C::raw()).per().read().per()
    }

    /// The primary duty is the period in which the primary switch is active
    ///
    /// In the case of a buck converter, this is the high-side switch
    /// In the case of a boost converter, this is the low-side switch
    pub fn set_primary_duty(&mut self, primary_duty: u16) {
        self.primary_duty = primary_duty;
        self.update_primary_duty_or_dead_time();
    }

    /// The secondary duty is the period in any switch is active
    ///
    /// If less than or equal to the primary duty, the secondary switch will be active for one tick
    /// If a fully complementary output is desired, the secondary duty can be set to the max compare
    pub fn set_secondary_duty(&mut self, secondary_duty: u16) {
        let secondary_duty = if secondary_duty > self.max_secondary_duty {
            self.max_secondary_duty
        } else if secondary_duty <= self.min_secondary_duty {
            self.min_secondary_duty + 1
        } else {
            secondary_duty
        };

        T::regs().tim(C::raw()).cmp(2).modify(|w| w.set_cmp(secondary_duty));
    }
}

/// Represents a variable-frequency resonant converter
///
/// This implementation of a resonsant converter is appropriate for a half or full bridge,
/// but does not include secondary rectification, which is appropriate for applications
/// with a low-voltage on the secondary side.
pub struct ResonantConverter<T: Instance, C: AdvancedChannel<T>> {
    timer: PhantomData<T>,
    channel: PhantomData<C>,
    min_period: u16,
    max_period: u16,
}

impl<T: Instance, C: AdvancedChannel<T>> ResonantConverter<T, C> {
    pub fn new(_channel: C, min_frequency: Hertz, max_frequency: Hertz) -> Self {
        T::set_channel_frequency(C::raw(), min_frequency);

        // Always enable preload
        T::regs().tim(C::raw()).cr().modify(|w| {
            w.set_preen(true);
            w.set_repu(true);

            w.set_cont(true);
            w.set_half(true);
        });

        // Enable timer outputs
        T::regs().oenr().modify(|w| {
            w.set_t1oen(C::raw(), true);
            w.set_t2oen(C::raw(), true);
        });

        // Dead-time generator can be used in this case because the primary fets
        // of a resonant converter are always complementary
        T::regs().tim(C::raw()).outr().modify(|w| w.set_dten(true));

        let max_period = T::regs().tim(C::raw()).per().read().per();
        let min_period = max_period * (min_frequency.0 / max_frequency.0) as u16;

        Self {
            timer: PhantomData,
            channel: PhantomData,
            min_period: min_period,
            max_period: max_period,
        }
    }

    /// Set the dead time as a proportion of the maximum compare value
    pub fn set_dead_time(&mut self, value: u16) {
        T::set_channel_dead_time(C::raw(), value);
    }

    pub fn set_period(&mut self, period: u16) {
        assert!(period < self.max_period);
        assert!(period > self.min_period);

        T::regs().tim(C::raw()).per().modify(|w| w.set_per(period));
    }

    /// Get the minimum compare value of a duty cycle
    pub fn get_min_period(&mut self) -> u16 {
        self.min_period
    }

    /// Get the maximum compare value of a duty cycle
    pub fn get_max_period(&mut self) -> u16 {
        self.max_period
    }
}

pin_trait!(ChannelAPin, Instance);
pin_trait!(ChannelAComplementaryPin, Instance);
pin_trait!(ChannelBPin, Instance);
pin_trait!(ChannelBComplementaryPin, Instance);
pin_trait!(ChannelCPin, Instance);
pin_trait!(ChannelCComplementaryPin, Instance);
pin_trait!(ChannelDPin, Instance);
pin_trait!(ChannelDComplementaryPin, Instance);
pin_trait!(ChannelEPin, Instance);
pin_trait!(ChannelEComplementaryPin, Instance);