use strum::FromRepr;

use crate::{
    clock::{RtcClock, RtcFastClock, RtcSlowClock},
    peripherals::LPWR,
    rtc_cntl::RtcCalSel,
};

pub(crate) fn init() {
    RtcClock::set_fast_freq(RtcFastClock::RcFast);
    RtcClock::set_slow_freq(RtcSlowClock::RcSlow);
}

pub(crate) fn configure_clock() {
    let cal_val = loop {
        let res = RtcClock::calibrate(RtcCalSel::RtcMux, 1024);
        if res != 0 {
            break res;
        }
    };

    LPWR::regs().store1().write(|w| unsafe { w.bits(cal_val) });
}

// Terminology:
//
// CPU Reset:    Reset CPU core only, once reset done, CPU will execute from
//               reset vector
// Core Reset:   Reset the whole digital system except RTC sub-system
// System Reset: Reset the whole digital system, including RTC sub-system
// Chip Reset:   Reset the whole chip, including the analog part

/// SOC Reset Reason.
#[derive(Debug, Clone, Copy, PartialEq, Eq, FromRepr)]
pub enum SocResetReason {
    /// Power on reset
    ///
    /// In ESP-IDF this value (0x01) can *also* be `ChipBrownOut` or
    /// `ChipSuperWdt`, however that is not really compatible with Rust-style
    /// enums.
    ChipPowerOn   = 0x01,
    /// Software resets the digital core by RTC_CNTL_SW_SYS_RST
    CoreSw        = 0x03,
    /// Deep sleep reset the digital core
    CoreDeepSleep = 0x05,
    /// Main watch dog 0 resets digital core
    CoreMwdt0     = 0x07,
    /// Main watch dog 1 resets digital core
    CoreMwdt1     = 0x08,
    /// RTC watch dog resets digital core
    CoreRtcWdt    = 0x09,
    /// Main watch dog 0 resets CPU
    ///
    /// In ESP-IDF there are `Cpu0Mwdt0` and `Cpu1Mwdt0`, however they have the
    /// same values.
    CpuMwdt0      = 0x0B,
    /// Software resets CPU by RTC_CNTL_SW_(PRO|APP)CPU_RST
    ///
    /// In ESP-IDF there are `Cpu0Sw` and `Cpu1Sw`, however they have the same
    /// values.
    CpuSw         = 0x0C,
    /// RTC watch dog resets CPU
    ///
    /// In ESP-IDF there are `Cpu0RtcWdt` and `Cpu1RtcWdt`, however they have
    /// the same values.
    CpuRtcWdt     = 0x0D,
    /// VDD voltage is not stable and resets the digital core
    SysBrownOut   = 0x0F,
    /// RTC watch dog resets digital core and rtc module
    SysRtcWdt     = 0x10,
    /// Main watch dog 1 resets CPU
    ///
    /// In ESP-IDF there are `Cpu0Mwdt1` and `Cpu1Mwdt1`, however they have the
    /// same values.
    CpuMwdt1      = 0x11,
    /// Super watch dog resets the digital core and rtc module
    SysSuperWdt   = 0x12,
    /// Glitch on clock resets the digital core and rtc module
    SysClkGlitch  = 0x13,
    /// eFuse CRC error resets the digital core
    CoreEfuseCrc  = 0x14,
    /// USB UART resets the digital core
    CoreUsbUart   = 0x15,
    /// USB JTAG resets the digital core
    CoreUsbJtag   = 0x16,
    /// Glitch on power resets the digital core
    CorePwrGlitch = 0x17,
}
