//============================================================================
// SimpleWriter - 带中断功能的写寄存器外设
//============================================================================

using System;
using Antmicro.Renode.Core;
using Antmicro.Renode.Logging;
using Antmicro.Renode.Peripherals.Bus;
using Antmicro.Renode.Peripherals.IRQControllers;

namespace Antmicro.Renode.Peripherals.Timers1
{
    public class SimpleWriter : IDoubleWordPeripheral, IKnownSize
    {
        // 寄存器偏移地址
        private const uint REG0_OFFSET = 0x0000;
        private const uint REG1_OFFSET = 0x0004;
        private const uint REG2_OFFSET = 0x0008;
        private const uint REG3_OFFSET = 0x000C;
        
        private const uint SIZE = 0x1000;

        // 寄存器值
        private uint reg0;
        private uint reg1;
        private uint reg2;
        private uint reg3;
        
        // 中断输出 - 必须为public，类型为GPIO
        public GPIO Interrupt { get; private set; }

        public SimpleWriter(IMachine machine)
        {

            this.Log(LogLevel.Info, "[中断输出创建] 中断触发: REG1低8位=0x{0:X2}, 中断=高电平", currentLow8Bits);

            // 创建中断输出
            Interrupt = new GPIO();

            this.Log(LogLevel.Info, "[中断输出创建] 中断触发: REG1低8位=0x{0:X2}, 中断=高电平", currentLow8Bits);
            
            // 初始化寄存器
            InitializeRegisters();
            
            LogInitializationInfo();
        }

        public void Reset()
        {
            InitializeRegisters();
            // 复位时清除中断
            Interrupt.Set(false);
        }
        
        /// <summary>
        /// 更新中断状态
        /// </summary>
        private void UpdateInterrupt()
        {
            uint currentLow8Bits = reg1 & 0xFF;
            bool interruptActive = (currentLow8Bits != 0);
            
            // 设置中断电平
            Interrupt.Set(interruptActive);
            
            if (interruptActive)
            {
                this.Log(LogLevel.Info, "[SimpleWriter] 中断触发: REG1低8位=0x{0:X2}, 中断=高电平", currentLow8Bits);
            }
            else
            {
                this.Log(LogLevel.Info, "[SimpleWriter] 中断清除: REG1低8位=0x00, 中断=低电平");
            }
        }

        private void InitializeRegisters()
        {
            reg0 = 0xFFFE8040;
            reg1 = 0x01F90040;  // 低8位=0x40，有1存在
            reg2 = 0x00000040;
            reg3 = 0x00000000;
            
            UpdateInterrupt();
        }

        public uint ReadDoubleWord(long offset)
        {
            uint value = 0;
            
            switch ((uint)offset)
            {
                case REG0_OFFSET:
                    value = reg0;
                    this.Log(LogLevel.Info, "[SimpleWriter] REG0读取: 0x{0:X8}", value);
                    break;
                case REG1_OFFSET:
                    value = reg1;
                    this.Log(LogLevel.Info, "[SimpleWriter] REG1读取: 0x{0:X8}", value);
                    break;
                case REG2_OFFSET:
                    value = reg2;
                    this.Log(LogLevel.Info, "[SimpleWriter] REG2读取: 0x{0:X8}", value);
                    break;
                case REG3_OFFSET:
                    value = reg3;
                    this.Log(LogLevel.Info, "[SimpleWriter] REG3读取: 0x{0:X8}", value);
                    break;
                default:
                    this.Log(LogLevel.Warning, "[SimpleWriter] 读取未定义地址: 0x{0:X8}", offset);
                    break;
            }
            
            return value;
        }

        public void WriteDoubleWord(long offset, uint value)
        {
            switch ((uint)offset)
            {
                case REG0_OFFSET:
                    this.Log(LogLevel.Info, "[SimpleWriter] REG0写入: 0x{0:X8}", value);
                    reg0 = value;
                    break;
                case REG1_OFFSET:
                    this.Log(LogLevel.Info, "[SimpleWriter] REG1写入: 旧值0x{0:X8}, 新值0x{1:X8}", reg1, value);
                    reg1 = value;
                    UpdateInterrupt();  // 写入REG1后更新中断状态
                    break;
                case REG2_OFFSET:
                    this.Log(LogLevel.Info, "[SimpleWriter] REG2写入: 0x{0:X8}", value);
                    reg2 = value;
                    break;
                case REG3_OFFSET:
                    this.Log(LogLevel.Info, "[SimpleWriter] REG3写入: 0x{0:X8}", value);
                    reg3 = value;
                    break;
                default:
                    this.Log(LogLevel.Warning, "[SimpleWriter] 写入未定义地址: 0x{0:X8} = 0x{1:X8}", offset, value);
                    break;
            }
        }

        public long Size => SIZE;

        private void LogInitializationInfo()
        {
            this.Log(LogLevel.Warning, "==========================================");
            this.Log(LogLevel.Warning, "SimpleWriter 已初始化");
            this.Log(LogLevel.Warning, "");
            this.Log(LogLevel.Warning, "寄存器初始化值：");
            this.Log(LogLevel.Warning, "  REG0: 0x{0:X8}", reg0);
            this.Log(LogLevel.Warning, "  REG1: 0x{0:X8} (低8位=0x{1:X2})", reg1, reg1 & 0xFF);
            this.Log(LogLevel.Warning, "  REG2: 0x{0:X8}", reg2);
            this.Log(LogLevel.Warning, "  REG3: 0x{0:X8}", reg3);
            this.Log(LogLevel.Warning, "");
            this.Log(LogLevel.Warning, "中断功能：当REG1低8位有任何1时，输出高电平中断");
            this.Log(LogLevel.Warning, "当前中断状态: {0}", (reg1 & 0xFF) != 0 ? "高电平" : "低电平");
            this.Log(LogLevel.Warning, "==========================================");
        }
    }
}