/** @file
  Main file for Help shell level 3 function.

  Copyright (c) 2009 - 2013, 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 "UefiShellLevel3CommandsLib.h"

#include <Library/ShellLib.h>

STATIC CONST SHELL_PARAM_ITEM ParamList[] = {
  {L"-usage", TypeFlag},
  {L"-section", TypeMaxValue},
  {L"-verbose", TypeFlag},
  {L"-v", TypeFlag},
  {NULL, TypeMax}
  };

/**
  Function for 'help' 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
ShellCommandRunHelp (
  IN EFI_HANDLE        ImageHandle,
  IN EFI_SYSTEM_TABLE  *SystemTable
  )
{
  EFI_STATUS          Status;
  LIST_ENTRY          *Package;
  CHAR16              *ProblemParam;
  SHELL_STATUS        ShellStatus;
  CONST COMMAND_LIST  *CommandList;
  CONST COMMAND_LIST  *Node;
  CHAR16              *CommandToGetHelpOn;
  CHAR16              *SectionToGetHelpOn;
  CHAR16              *HiiString;
  BOOLEAN             Found;
  BOOLEAN             PrintCommandText;

  PrintCommandText    = TRUE;
  ProblemParam        = NULL;
  ShellStatus         = SHELL_SUCCESS;
  CommandToGetHelpOn  = NULL;
  SectionToGetHelpOn  = NULL;
  Found               = FALSE;

  //
  // 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), gShellLevel3HiiHandle, ProblemParam);
      FreePool(ProblemParam);
      ShellStatus = SHELL_INVALID_PARAMETER;
    } else {
      ASSERT(FALSE);
    }
  } else {
    //
    // Check for conflicting parameters.
    //
    if (ShellCommandLineGetFlag(Package, L"-usage")
      &&ShellCommandLineGetFlag(Package, L"-section")
      &&(ShellCommandLineGetFlag(Package, L"-verbose") || ShellCommandLineGetFlag(Package, L"-v"))
     ){
      ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_GEN_PARAM_CON), gShellLevel3HiiHandle);
      ShellStatus = SHELL_INVALID_PARAMETER;
    } else if (ShellCommandLineGetRawValue(Package, 2) != NULL) {
      ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_GEN_TOO_MANY), gShellLevel3HiiHandle);
      ShellStatus = SHELL_INVALID_PARAMETER;
    } else {
      //
      // Get the command name we are getting help on
      //
      ASSERT(CommandToGetHelpOn == NULL);
      StrnCatGrow(&CommandToGetHelpOn, NULL, ShellCommandLineGetRawValue(Package, 1), 0);
      if (CommandToGetHelpOn == NULL && ShellCommandLineGetFlag(Package, L"-?")) {
        //
        // If we dont have a command and we got a simple -?
        // we are looking for help on help command.
        //
        StrnCatGrow(&CommandToGetHelpOn, NULL, L"help", 0);
      }

      if (CommandToGetHelpOn == NULL) {
        StrnCatGrow(&CommandToGetHelpOn, NULL, L"*", 0);
        ASSERT(SectionToGetHelpOn == NULL);
        StrnCatGrow(&SectionToGetHelpOn, NULL, L"NAME", 0);
      } else {
        PrintCommandText = FALSE;
        ASSERT(SectionToGetHelpOn == NULL);
        //
        // Get the section name for the given command name
        //
        if (ShellCommandLineGetFlag(Package, L"-section")) {
          StrnCatGrow(&SectionToGetHelpOn, NULL, ShellCommandLineGetValue(Package, L"-section"), 0);
        } else if (ShellCommandLineGetFlag(Package, L"-usage")) {
          StrnCatGrow(&SectionToGetHelpOn, NULL, L"NAME,SYNOPSIS", 0);
        } else if (ShellCommandLineGetFlag(Package, L"-verbose") || ShellCommandLineGetFlag(Package, L"-v")) {
        } else {
          //
          // The output of help <command> will display NAME, SYNOPSIS, OPTIONS, DESCRIPTION, and EXAMPLES sections.
          //
          StrnCatGrow (&SectionToGetHelpOn, NULL, L"NAME,SYNOPSIS,OPTIONS,DESCRIPTION,EXAMPLES", 0);
        }
      }

      if (gUnicodeCollation->StriColl(gUnicodeCollation, CommandToGetHelpOn, L"special") == 0) {
        //
        // we need info on the special characters
        //
        ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_HELP_SC_HEADER), gShellLevel3HiiHandle);
        HiiString = HiiGetString(gShellLevel3HiiHandle, STRING_TOKEN(STR_HELP_SC_DATA), NULL);
        ShellPrintEx(-1, -1, L"%s", HiiString);
        FreePool(HiiString);
        Found = TRUE;
      } else {
        CommandList = ShellCommandGetCommandList(TRUE);
        ASSERT(CommandList != NULL);
        for ( Node = (COMMAND_LIST*)GetFirstNode(&CommandList->Link)
            ; CommandList != NULL && !IsListEmpty(&CommandList->Link) && !IsNull(&CommandList->Link, &Node->Link)
            ; Node = (COMMAND_LIST*)GetNextNode(&CommandList->Link, &Node->Link)
           ){
          //
          // Checking execution break flag when print multiple command help information.
          //
          if (ShellGetExecutionBreakFlag ()) {
            break;
          } 
          if ((gUnicodeCollation->MetaiMatch(gUnicodeCollation, Node->CommandString, CommandToGetHelpOn)) ||
             (gEfiShellProtocol->GetAlias(CommandToGetHelpOn, NULL) != NULL && (gUnicodeCollation->MetaiMatch(gUnicodeCollation, Node->CommandString, (CHAR16*)(gEfiShellProtocol->GetAlias(CommandToGetHelpOn, NULL)))))) {
            //
            // We have a command to look for help on.
            //
            Status = ShellPrintHelp(Node->CommandString, SectionToGetHelpOn, PrintCommandText);
            if (Status == EFI_DEVICE_ERROR) {
                ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_HELP_INV), gShellLevel3HiiHandle, Node->CommandString);
            } else if (EFI_ERROR(Status)) {
                ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_HELP_NF), gShellLevel3HiiHandle, Node->CommandString);
            } else {
                Found = TRUE;
            }
          }
        }
        //
        // Search the .man file for Shell applications (Shell external commands).
        //
        if (!Found) {
            Status = ShellPrintHelp(CommandToGetHelpOn, SectionToGetHelpOn, FALSE);
            if (Status == EFI_DEVICE_ERROR) {
               ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_HELP_INV), gShellLevel3HiiHandle, CommandToGetHelpOn);
            } else if (EFI_ERROR(Status)) {
               ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_HELP_NF), gShellLevel3HiiHandle, CommandToGetHelpOn);
            } else {
              Found = TRUE;
            }
        }
      }

      if (!Found) {
        ShellStatus = SHELL_NOT_FOUND;
      }

      //
      // free the command line package
      //
      ShellCommandLineFreeVarList (Package);
    }
  }

  if (CommandToGetHelpOn != NULL && StrCmp(CommandToGetHelpOn, L"*") == 0){
    //
    // If '*' then the command entered was 'Help' without qualifiers, This footer
    // provides additional info on help switches
    //
    ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_HELP_FOOTER), gShellLevel3HiiHandle);
  }
  if (CommandToGetHelpOn != NULL) {
    FreePool(CommandToGetHelpOn);
  }
  if (SectionToGetHelpOn != NULL) {
    FreePool(SectionToGetHelpOn);
  }

  return (ShellStatus);
}