import { MAX_HARDWARE_IRQ } from '../irq.js';
import { Timer32, Timer32PeriodicAlarm, TimerMode } from '../utils/timer32.js';
import { BasePeripheral } from './peripheral.js';
export const CPUID = 0xd00;
export const ICSR = 0xd04;
export const VTOR = 0xd08;
export const SHPR2 = 0xd1c;
export const SHPR3 = 0xd20;
const SYST_CSR = 0x010; // SysTick Control and Status Register
const SYST_RVR = 0x014; // SysTick Reload Value Register
const SYST_CVR = 0x018; // SysTick Current Value Register
const SYST_CALIB = 0x01c; // SysTick Calibration Value Register
const NVIC_ISER = 0x100; // Interrupt Set-Enable Register
const NVIC_ICER = 0x180; // Interrupt Clear-Enable Register
const NVIC_ISPR = 0x200; // Interrupt Set-Pending Register
const NVIC_ICPR = 0x280; // Interrupt Clear-Pending Register
// Interrupt priority registers:
const NVIC_IPR0 = 0x400;
const NVIC_IPR1 = 0x404;
const NVIC_IPR2 = 0x408;
const NVIC_IPR3 = 0x40c;
const NVIC_IPR4 = 0x410;
const NVIC_IPR5 = 0x414;
const NVIC_IPR6 = 0x418;
const NVIC_IPR7 = 0x41c;
/** ICSR Bits */
const NMIPENDSET = 1 << 31;
const PENDSVSET = 1 << 28;
const PENDSVCLR = 1 << 27;
const PENDSTSET = 1 << 26;
const PENDSTCLR = 1 << 25;
const ISRPREEMPT = 1 << 23;
const ISRPENDING = 1 << 22;
const VECTPENDING_MASK = 0x1ff;
const VECTPENDING_SHIFT = 12;
const VECTACTIVE_MASK = 0x1ff;
const VECTACTIVE_SHIFT = 0;
/** PPB stands for Private Periphral Bus.
 * These are peripherals that are part of the ARM Cortex Core, and there's one copy for each processor core.
 *
 * Included peripheral: NVIC, SysTick timer
 */
export class RPPPB extends BasePeripheral {
    constructor(rp2040, name) {
        super(rp2040, name);
        // Systick
        this.systickCountFlag = false;
        this.systickClkSource = false;
        this.systickIntEnable = false;
        this.systickReload = 0;
        this.systickTimer = new Timer32(this.rp2040.clock, this.rp2040.clkSys);
        this.systickAlarm = new Timer32PeriodicAlarm(this.systickTimer, () => {
            this.systickCountFlag = true;
            if (this.systickIntEnable) {
                this.rp2040.core.pendingSystick = true;
                this.rp2040.core.interruptsUpdated = true;
            }
            this.systickTimer.set(this.systickReload);
        });
        this.systickTimer.top = 0xffffff;
        this.systickTimer.mode = TimerMode.Decrement;
        this.systickAlarm.target = 0;
        this.systickAlarm.enable = true;
        this.reset();
    }
    reset() {
        this.writeUint32(SYST_CSR, 0);
        this.writeUint32(SYST_RVR, 0xffffff);
        this.systickTimer.set(0xffffff);
    }
    readUint32(offset) {
        const { rp2040 } = this;
        const { core } = rp2040;
        switch (offset) {
            case CPUID:
                return 0x410cc601; /* Verified against actual hardware */
            case ICSR: {
                const pendingInterrupts = core.pendingInterrupts || core.pendingPendSV || core.pendingSystick || core.pendingSVCall;
                const vectPending = core.vectPending;
                return ((core.pendingNMI ? NMIPENDSET : 0) |
                    (core.pendingPendSV ? PENDSVSET : 0) |
                    (core.pendingSystick ? PENDSTSET : 0) |
                    (pendingInterrupts ? ISRPENDING : 0) |
                    (vectPending << VECTPENDING_SHIFT) |
                    ((core.IPSR & VECTACTIVE_MASK) << VECTACTIVE_SHIFT));
            }
            case VTOR:
                return core.VTOR;
            /* NVIC */
            case NVIC_ISPR:
                return core.pendingInterrupts >>> 0;
            case NVIC_ICPR:
                return core.pendingInterrupts >>> 0;
            case NVIC_ISER:
                return core.enabledInterrupts >>> 0;
            case NVIC_ICER:
                return core.enabledInterrupts >>> 0;
            case NVIC_IPR0:
            case NVIC_IPR1:
            case NVIC_IPR2:
            case NVIC_IPR3:
            case NVIC_IPR4:
            case NVIC_IPR5:
            case NVIC_IPR6:
            case NVIC_IPR7: {
                const regIndex = (offset - NVIC_IPR0) >> 2;
                let result = 0;
                for (let byteIndex = 0; byteIndex < 4; byteIndex++) {
                    const interruptNumber = regIndex * 4 + byteIndex;
                    for (let priority = 0; priority < core.interruptPriorities.length; priority++) {
                        if (core.interruptPriorities[priority] & (1 << interruptNumber)) {
                            result |= priority << (8 * byteIndex + 6);
                        }
                    }
                }
                return result;
            }
            case SHPR2:
                return core.SHPR2;
            case SHPR3:
                return core.SHPR3;
            /* SysTick */
            case SYST_CSR: {
                const countFlagValue = this.systickCountFlag ? 1 << 16 : 0;
                const clkSourceValue = this.systickClkSource ? 1 << 2 : 0;
                const tickIntValue = this.systickIntEnable ? 1 << 1 : 0;
                const enableFlagValue = this.systickTimer.enable ? 1 << 0 : 0;
                this.systickCountFlag = false;
                return countFlagValue | clkSourceValue | tickIntValue | enableFlagValue;
            }
            case SYST_CVR:
                return this.systickTimer.counter;
            case SYST_RVR:
                return this.systickReload;
            case SYST_CALIB:
                return 0x0000270f;
        }
        return super.readUint32(offset);
    }
    writeUint32(offset, value) {
        const { rp2040 } = this;
        const { core } = rp2040;
        const hardwareInterruptMask = (1 << MAX_HARDWARE_IRQ) - 1;
        switch (offset) {
            case ICSR:
                if (value & NMIPENDSET) {
                    core.pendingNMI = true;
                    core.interruptsUpdated = true;
                }
                if (value & PENDSVSET) {
                    core.pendingPendSV = true;
                    core.interruptsUpdated = true;
                }
                if (value & PENDSVCLR) {
                    core.pendingPendSV = false;
                }
                if (value & PENDSTSET) {
                    core.pendingSystick = true;
                    core.interruptsUpdated = true;
                }
                if (value & PENDSTCLR) {
                    core.pendingSystick = false;
                }
                return;
            case VTOR:
                core.VTOR = value;
                return;
            /* NVIC */
            case NVIC_ISPR:
                core.pendingInterrupts |= value;
                core.interruptsUpdated = true;
                return;
            case NVIC_ICPR:
                core.pendingInterrupts &= ~value | hardwareInterruptMask;
                return;
            case NVIC_ISER:
                core.enabledInterrupts |= value;
                core.interruptsUpdated = true;
                return;
            case NVIC_ICER:
                core.enabledInterrupts &= ~value;
                return;
            case NVIC_IPR0:
            case NVIC_IPR1:
            case NVIC_IPR2:
            case NVIC_IPR3:
            case NVIC_IPR4:
            case NVIC_IPR5:
            case NVIC_IPR6:
            case NVIC_IPR7: {
                const regIndex = (offset - NVIC_IPR0) >> 2;
                for (let byteIndex = 0; byteIndex < 4; byteIndex++) {
                    const interruptNumber = regIndex * 4 + byteIndex;
                    const newPriority = (value >> (8 * byteIndex + 6)) & 0x3;
                    for (let priority = 0; priority < core.interruptPriorities.length; priority++) {
                        core.interruptPriorities[priority] &= ~(1 << interruptNumber);
                    }
                    core.interruptPriorities[newPriority] |= 1 << interruptNumber;
                }
                core.interruptsUpdated = true;
                return;
            }
            case SHPR2:
                core.SHPR2 = value;
                return;
            case SHPR3:
                core.SHPR3 = value;
                return;
            // SysTick
            case SYST_CSR:
                this.systickClkSource = value & (1 << 2) ? true : false;
                this.systickIntEnable = value & (1 << 1) ? true : false;
                this.systickTimer.enable = value & (1 << 0) ? true : false;
                return;
            case SYST_CVR:
                this.systickTimer.set(0);
                return;
            case SYST_RVR:
                this.systickReload = value;
                return;
            default:
                super.writeUint32(offset, value);
        }
    }
}