#include <stdint.h>
#include <stdio.h>
#include "riscv-traps.h"
#include "riscv-csr.h"

// Expect this to increment one time per second - inside exception handler, after each return of MTI handler.
static volatile uint64_t ecall_count = 0;

void exception(uintptr_t mcause, uintptr_t mepc, uintptr_t mtval) {
    switch(mcause) {
        case RISCV_EXCP_INSTRUCTION_ADDRESS_MISALIGNED: {
            puts("[EXCEPTION] : Instruction address misaligned\n");
            break;
        }
        case RISCV_EXCP_INSTRUCTION_ACCESS_FAULT: {
            puts("[EXCEPTION] : Instruction access fault\n");
            break;
        }
        case RISCV_EXCP_ILLEGAL_INSTRUCTION: {
            puts("[EXCEPTION] : Illegal Instruction\n");
            break;
        }
        case RISCV_EXCP_BREAKPOINT: {
            puts("[EXCEPTION] : Breakpoint\n");
            break;
        }
        case RISCV_EXCP_LOAD_ADDRESS_MISALIGNED: {
            puts("[EXCEPTION] : Load address misaligned");
            printf("[EXCEPTION] : PC: 0x%x\n", mepc);
            printf("[EXCEPTION] : Addr: 0x%x\n", mtval);
            break;
        }
        case RISCV_EXCP_LOAD_ACCESS_FAULT: {
            puts("[EXCEPTION] : Load access fault\n");
            break;
        }
        case RISCV_EXCP_STORE_AMO_ADDRESS_MISALIGNED: {
            puts("[EXCEPTION] : Store/AMO address misaligned");
            printf("[EXCEPTION] : PC: 0x%x\n", mepc);
            printf("[EXCEPTION] : Addr: 0x%x\n", mtval);
            break;
        }
        case RISCV_EXCP_STORE_AMO_ACCESS_FAULT: {
            puts("[EXCEPTION] : Store/AMO access fault\n");
            break;
        }
        case RISCV_EXCP_ENVIRONMENT_CALL_FROM_U_MODE: {
            puts("[EXCEPTION] : Environment call from U-mode\n");
            break;
        }
        case RISCV_EXCP_ENVIRONMENT_CALL_FROM_S_MODE: {
            puts("[EXCEPTION] : Environment call from S-mode\n");
            break;
        }
        case RISCV_EXCP_ENVIRONMENT_CALL_FROM_M_MODE: {
            puts("[EXCEPTION] : Environment call from M-mode\n");
            ecall_count++;
            csr_write_mepc(mepc+4);
            break;
        }
        case RISCV_EXCP_INSTRUCTION_PAGE_FAULT: {
            puts("[EXCEPTION] : Instruction page fault\n");
            break;
        }
        case RISCV_EXCP_LOAD_PAGE_FAULT: {
            puts("[EXCEPTION] : Load page fault\n");
            break;
        }
        case RISCV_EXCP_STORE_AMO_PAGE_FAULT: {
            puts("[EXCEPTION] : Store/AMO page fault\n");
            break;
        }
        default: {
            printf("[EXCEPTION] : Unknown trap cause: %lu\n", mcause);
        }
    }
    while(1)
        ;
}