/** @file
  Main file for Comp shell Debug1 function.

  (C) Copyright 2015 Hewlett-Packard Development Company, L.P.<BR>
  Copyright (c) 2010 - 2017, Intel Corporation. All rights reserved.<BR>
  This program and the accompanying materials
  are licensed and made available under the terms and conditions of the BSD License
  which accompanies this distribution.  The full text of the license may be found at
  http://opensource.org/licenses/bsd-license.php

  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

**/

#include "UefiShellDebug1CommandsLib.h"

STATIC CONST SHELL_PARAM_ITEM ParamList[] = {
  {L"-n", TypeValue},
  {L"-s", TypeValue},
  {NULL,  TypeMax}
  };

typedef enum {
  OutOfDiffPoint,
  InDiffPoint,
  InPrevDiffPoint
} READ_STATUS;

/**
  Function to print differnt point data.

  @param[in]  FileName        File name
  @param[in]  Buffer          Data buffer to be printed.
  @param[in]  BufferSize      Size of the data to be printed.
  @param[in]  Address         Address of the differnt point.
  @param[in]  DifferentBytes  Total size of the buffer.

**/
VOID
PrintDifferentPoint(
  CONST CHAR16  *FileName,
  UINT8         *Buffer,
  UINT64        BufferSize,
  UINTN         Address,
  UINT64        DifferentBytes
  )
{
  UINTN Index;

  ShellPrintEx (-1, -1, L"%s: %s\r\n  %08x:", L"File1", FileName, Address);

  //
  // Print data in hex-format.
  //
  for (Index = 0; Index < BufferSize; Index++) {
    ShellPrintEx (-1, -1, L" %02x", Buffer[Index]);
  }

  if (BufferSize < DifferentBytes) {
    ShellPrintHiiEx (-1, -1, NULL, STRING_TOKEN (STR_COMP_END_OF_FILE), gShellDebug1HiiHandle);
  }

  ShellPrintEx (-1, -1, L"    *");

  //
  // Print data in char-format.
  //
  for (Index = 0; Index < BufferSize; Index++) {
    if (Buffer[Index] >= 0x20 && Buffer[Index] <= 0x7E) {
      ShellPrintEx (-1, -1, L"%c", Buffer[Index]);
    } else {
      //
      // Print dots for control characters
      //
      ShellPrintEx (-1, -1, L".");
    }
  }

  ShellPrintEx (-1, -1, L"*\r\n");
}

/**
  Function for 'comp' command.

  @param[in] ImageHandle  Handle to the Image (NULL if Internal).
  @param[in] SystemTable  Pointer to the System Table (NULL if Internal).
**/
SHELL_STATUS
EFIAPI
ShellCommandRunComp (
  IN EFI_HANDLE        ImageHandle,
  IN EFI_SYSTEM_TABLE  *SystemTable
  )
{
  EFI_STATUS          Status;
  LIST_ENTRY          *Package;
  CHAR16              *ProblemParam;
  CHAR16              *FileName1;
  CHAR16              *FileName2;
  CONST CHAR16        *TempParam;
  SHELL_STATUS        ShellStatus;
  SHELL_FILE_HANDLE   FileHandle1;
  SHELL_FILE_HANDLE   FileHandle2;
  UINT64              Size1;
  UINT64              Size2;
  UINT64              DifferentBytes;
  UINT64              DifferentCount;
  UINT8               DiffPointNumber;
  UINT8               OneByteFromFile1;
  UINT8               OneByteFromFile2;
  UINT8               *DataFromFile1;
  UINT8               *DataFromFile2;
  UINTN               InsertPosition1;
  UINTN               InsertPosition2;
  UINTN               DataSizeFromFile1;
  UINTN               DataSizeFromFile2;
  UINTN               TempAddress;
  UINTN               Index;
  UINTN               DiffPointAddress;
  READ_STATUS         ReadStatus;

  ShellStatus         = SHELL_SUCCESS;
  Status              = EFI_SUCCESS;
  FileName1           = NULL;
  FileName2           = NULL;
  FileHandle1         = NULL;
  FileHandle2         = NULL;
  DataFromFile1       = NULL;
  DataFromFile2       = NULL;
  ReadStatus          = OutOfDiffPoint;
  DifferentCount      = 10;
  DifferentBytes      = 4;
  DiffPointNumber     = 0;
  InsertPosition1     = 0;
  InsertPosition2     = 0;
  TempAddress         = 0;
  DiffPointAddress    = 0;

  //
  // initialize the shell lib (we must be in non-auto-init...)
  //
  Status = ShellInitialize();
  ASSERT_EFI_ERROR(Status);

  Status = CommandInit();
  ASSERT_EFI_ERROR(Status);

  //
  // parse the command line
  //
  Status = ShellCommandLineParse (ParamList, &Package, &ProblemParam, TRUE);
  if (EFI_ERROR(Status)) {
    if (Status == EFI_VOLUME_CORRUPTED && ProblemParam != NULL) {
      ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_GEN_PROBLEM), gShellDebug1HiiHandle, L"comp", ProblemParam);  
      FreePool(ProblemParam);
      ShellStatus = SHELL_INVALID_PARAMETER;
    } else {
      ASSERT(FALSE);
    }
  } else {
    if (ShellCommandLineGetCount(Package) > 3) {
      ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_GEN_TOO_MANY), gShellDebug1HiiHandle, L"comp");  
      ShellStatus = SHELL_INVALID_PARAMETER;
    } else if (ShellCommandLineGetCount(Package) < 3) {
      ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_GEN_TOO_FEW), gShellDebug1HiiHandle, L"comp");  
      ShellStatus = SHELL_INVALID_PARAMETER;
    } else {
      TempParam = ShellCommandLineGetRawValue(Package, 1);
      ASSERT(TempParam != NULL);
      FileName1 = ShellFindFilePath(TempParam);
      if (FileName1 == NULL) {
        ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_FILE_FIND_FAIL), gShellDebug1HiiHandle, L"comp", TempParam);  
        ShellStatus = SHELL_NOT_FOUND;
      } else {
        Status = ShellOpenFileByName(FileName1, &FileHandle1, EFI_FILE_MODE_READ, 0);
        if (EFI_ERROR(Status)) {
          ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_GEN_FILE_OPEN_FAIL), gShellDebug1HiiHandle, L"comp", TempParam);  
          ShellStatus = SHELL_NOT_FOUND;
        }
      }
      TempParam = ShellCommandLineGetRawValue(Package, 2);
      ASSERT(TempParam != NULL);
      FileName2 = ShellFindFilePath(TempParam);
      if (FileName2 == NULL) {
        ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_FILE_FIND_FAIL), gShellDebug1HiiHandle, L"comp", TempParam);  
        ShellStatus = SHELL_NOT_FOUND;
      } else {
        Status = ShellOpenFileByName(FileName2, &FileHandle2, EFI_FILE_MODE_READ, 0);
        if (EFI_ERROR(Status)) {
          ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_GEN_FILE_OPEN_FAIL), gShellDebug1HiiHandle, L"comp", TempParam);  
          ShellStatus = SHELL_NOT_FOUND;
        }
      }
      if (ShellStatus == SHELL_SUCCESS) {
        Status = gEfiShellProtocol->GetFileSize(FileHandle1, &Size1);
        ASSERT_EFI_ERROR(Status);
        Status = gEfiShellProtocol->GetFileSize(FileHandle2, &Size2);
        ASSERT_EFI_ERROR(Status);

        if (ShellCommandLineGetFlag (Package, L"-n")) {
          TempParam = ShellCommandLineGetValue (Package, L"-n");
          if (TempParam == NULL) {
            ShellPrintHiiEx (-1, -1, NULL, STRING_TOKEN (STR_GEN_NO_VALUE), gShellDebug1HiiHandle, L"comp", L"-n");
            ShellStatus = SHELL_INVALID_PARAMETER;
          } else {
            if (gUnicodeCollation->StriColl (gUnicodeCollation, (CHAR16 *)TempParam, L"all") == 0) {
              DifferentCount = MAX_UINTN;
            } else {
              Status = ShellConvertStringToUint64 (TempParam, &DifferentCount, FALSE, TRUE);
              if (EFI_ERROR(Status) || DifferentCount == 0) {
                ShellPrintHiiEx (-1, -1, NULL, STRING_TOKEN (STR_GEN_PROBLEM_VAL), gShellDebug1HiiHandle, L"comp", TempParam, L"-n");
                ShellStatus = SHELL_INVALID_PARAMETER;
              }
            }
          }
        }

        if (ShellCommandLineGetFlag (Package, L"-s")) {
          TempParam = ShellCommandLineGetValue (Package, L"-s");
          if (TempParam == NULL) {
            ShellPrintHiiEx (-1, -1, NULL, STRING_TOKEN (STR_GEN_NO_VALUE), gShellDebug1HiiHandle, L"comp", L"-s");
            ShellStatus = SHELL_INVALID_PARAMETER;
          } else {
            Status = ShellConvertStringToUint64 (TempParam, &DifferentBytes, FALSE, TRUE);
            if (EFI_ERROR(Status) || DifferentBytes == 0) {
              ShellPrintHiiEx (-1, -1, NULL, STRING_TOKEN (STR_GEN_PROBLEM_VAL), gShellDebug1HiiHandle, L"comp", TempParam, L"-s");
              ShellStatus = SHELL_INVALID_PARAMETER;
            } else {
              if (DifferentBytes > MAX (Size1, Size2)) {
                DifferentBytes = MAX (Size1, Size2);
              }
            }
          }
        }
      }

      if (ShellStatus == SHELL_SUCCESS) {
        DataFromFile1 = AllocateZeroPool ((UINTN)DifferentBytes);
        DataFromFile2 = AllocateZeroPool ((UINTN)DifferentBytes);
        if (DataFromFile1 == NULL || DataFromFile2 == NULL) {
          ShellStatus = SHELL_OUT_OF_RESOURCES;
          SHELL_FREE_NON_NULL (DataFromFile1);
          SHELL_FREE_NON_NULL (DataFromFile2);
        }
      }

      if (ShellStatus == SHELL_SUCCESS) {
        while (DiffPointNumber < DifferentCount) {
          DataSizeFromFile1 = 1;
          DataSizeFromFile2 = 1;
          OneByteFromFile1 = 0;
          OneByteFromFile2 = 0;
          Status = gEfiShellProtocol->ReadFile (FileHandle1, &DataSizeFromFile1, &OneByteFromFile1);
          ASSERT_EFI_ERROR (Status);
          Status = gEfiShellProtocol->ReadFile (FileHandle2, &DataSizeFromFile2, &OneByteFromFile2);
          ASSERT_EFI_ERROR (Status);

          TempAddress++;

          //
          // 1.When end of file and no chars in DataFromFile buffer, then break while.
          // 2.If no more char in File1 or File2, The ReadStatus is InPrevDiffPoint forever.
          //   So the previous different point is the last one, then break the while block.
          //
          if ( (DataSizeFromFile1 == 0 && InsertPosition1 == 0 && DataSizeFromFile2 == 0 && InsertPosition2 == 0) ||
               (ReadStatus == InPrevDiffPoint && (DataSizeFromFile1 == 0 || DataSizeFromFile2 == 0))
             ) {
            break;
          }

          if (ReadStatus == OutOfDiffPoint) {
            if (OneByteFromFile1 != OneByteFromFile2) {
              ReadStatus = InDiffPoint;
              DiffPointAddress = TempAddress;
              if (DataSizeFromFile1 == 1) {
                DataFromFile1[InsertPosition1++] = OneByteFromFile1;
              }
              if (DataSizeFromFile2 == 1) {
                DataFromFile2[InsertPosition2++] = OneByteFromFile2;
              }
            }
          } else if (ReadStatus == InDiffPoint) {
            if (DataSizeFromFile1 == 1) {
              DataFromFile1[InsertPosition1++] = OneByteFromFile1;
            }
            if (DataSizeFromFile2 == 1) {
              DataFromFile2[InsertPosition2++] = OneByteFromFile2;
            }
          } else if (ReadStatus == InPrevDiffPoint) {
            if (OneByteFromFile1 == OneByteFromFile2) {
              ReadStatus = OutOfDiffPoint;
            }
          }

          //
          // ReadStatus should be always equal InDiffPoint.
          //
          if ( InsertPosition1 == DifferentBytes ||
               InsertPosition2 == DifferentBytes ||
               (DataSizeFromFile1 == 0 && DataSizeFromFile2 == 0)
             ) {

            ShellPrintHiiEx (-1, -1, NULL, STRING_TOKEN (STR_COMP_DIFFERENCE_POINT), gShellDebug1HiiHandle, ++DiffPointNumber);
            PrintDifferentPoint (FileName1, DataFromFile1, InsertPosition1, DiffPointAddress, DifferentBytes);
            PrintDifferentPoint (FileName2, DataFromFile2, InsertPosition2, DiffPointAddress, DifferentBytes);

            //
            // One of two buffuers is empty, it means this is the last different point.
            //
            if (InsertPosition1 == 0 || InsertPosition2 == 0) {
              break;
            }

            for (Index = 1; Index < InsertPosition1 && Index < InsertPosition2; Index++) {
              if (DataFromFile1[Index] == DataFromFile2[Index]) {
                ReadStatus = OutOfDiffPoint;
                break;
              }
            }

            if (ReadStatus == OutOfDiffPoint) {
              //
              // Try to find a new different point in the rest of DataFromFile.
              //
              for (; Index < MAX (InsertPosition1,InsertPosition2); Index++) {
                if (DataFromFile1[Index] != DataFromFile2[Index]) {
                  ReadStatus = InDiffPoint;
                  DiffPointAddress += Index;
                  break;
                }
              }
            } else {
              //
              // Doesn't find a new different point, still in the same different point.
              //
              ReadStatus = InPrevDiffPoint;
            }

            CopyMem (DataFromFile1, DataFromFile1 + Index, InsertPosition1 - Index);
            CopyMem (DataFromFile2, DataFromFile2 + Index, InsertPosition2 - Index);

            SetMem (DataFromFile1 + InsertPosition1 - Index, (UINTN)DifferentBytes - InsertPosition1 + Index, 0);
            SetMem (DataFromFile2 + InsertPosition2 - Index, (UINTN)DifferentBytes - InsertPosition2 + Index, 0);

            InsertPosition1 -= Index;
            InsertPosition2 -= Index;
          }
        }

        SHELL_FREE_NON_NULL (DataFromFile1);
        SHELL_FREE_NON_NULL (DataFromFile2);

        if (DiffPointNumber == 0) {
          ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_COMP_FOOTER_PASS), gShellDebug1HiiHandle);
        } else {
          ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_COMP_FOOTER_FAIL), gShellDebug1HiiHandle);
        }
      }
    }

    ShellCommandLineFreeVarList (Package);
  }
  SHELL_FREE_NON_NULL(FileName1);
  SHELL_FREE_NON_NULL(FileName2);

  if (FileHandle1 != NULL) {
    gEfiShellProtocol->CloseFile(FileHandle1);
  }
  if (FileHandle2 != NULL) {
    gEfiShellProtocol->CloseFile(FileHandle2);
  }

  return (ShellStatus);
}