/*---------------------------------------------------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     |
    \\  /    A nd           | Copyright (C) 2011-2016 OpenFOAM Foundation
     \\/     M anipulation  |
-------------------------------------------------------------------------------
License
    This file is part of OpenFOAM.

    OpenFOAM is free software: you can redistribute it and/or modify it
    under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
    for more details.

    You should have received a copy of the GNU General Public License
    along with OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.

Application
    changeDictionary

Description
    Utility to change dictionary entries, e.g. can be used to change the patch
    type in the field and polyMesh/boundary files.

    Reads dictionaries (fields) and entries to change from a dictionary.
    E.g. to make the \em movingWall a \em fixedValue for \em p but all other
    \em Walls a zeroGradient boundary condition, the
    \c system/changeDictionaryDict would contain the following:
    \verbatim
    p                           // field to change
    {
        boundaryField
        {
            ".*Wall"            // entry to change
            {
                type            zeroGradient;
            }
            movingWall          // entry to change
            {
                type            fixedValue;
                value           uniform 123.45;
            }
        }
    }
    \endverbatim
    Replacement entries starting with '~' will remove the entry.

Usage
    \b changeDictionary [OPTION]

    Options:
      - \par -subDict
        Specify the subDict name of the replacements dictionary.

      - \par -literalRE
        Do not interpret regular expressions or patchGroups; treat them as any
        other keyword.

      - \par -enableFunctionEntries
        Enable function entries (default: disabled)

      - \par -disablePatchGroups
        Disable the default checking for keys being patchGroups

\*---------------------------------------------------------------------------*/

#include "argList.H"
#include "IOobjectList.H"
#include "IOPtrList.H"
#include "volFields.H"
#include "stringListOps.H"
#include "timeSelector.H"

using namespace Foam;

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

namespace Foam
{
    defineTemplateTypeNameAndDebug(IOPtrList<entry>, 0);
}


// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

// Extract groupPatch info from boundary file info
HashTable<wordList, word> extractPatchGroups(const dictionary& boundaryDict)
{
    HashTable<wordList, word> groupToPatch;

    forAllConstIter(dictionary, boundaryDict, iter)
    {
        const word& patchName = iter().keyword();
        const dictionary& patchDict = iter().dict();

        wordList groups;
        if (patchDict.readIfPresent("inGroups", groups))
        {
            forAll(groups, i)
            {
                HashTable<wordList, word>::iterator fndGroup = groupToPatch.find
                (
                    groups[i]
                );
                if (fndGroup == groupToPatch.end())
                {
                    groupToPatch.insert(groups[i], wordList(1, patchName));
                }
                else
                {
                    fndGroup().append(patchName);
                }
            }
        }
    }
    return groupToPatch;
}


bool merge
(
    dictionary&,
    const dictionary&,
    const bool,
    const HashTable<wordList, word>&
);


// Add thisEntry to dictionary thisDict.
bool addEntry
(
    dictionary& thisDict,
    entry& thisEntry,
    const entry& mergeEntry,
    const bool literalRE,
    const HashTable<wordList, word>& shortcuts
)
{
    bool changed = false;

    // Recursively merge sub-dictionaries
    // TODO: merge without copying
    if (thisEntry.isDict() && mergeEntry.isDict())
    {
        if
        (
            merge
            (
                const_cast<dictionary&>(thisEntry.dict()),
                mergeEntry.dict(),
                literalRE,
                shortcuts
            )
        )
        {
            changed = true;
        }
    }
    else
    {
        // Should use in-place modification instead of adding
        thisDict.add(mergeEntry.clone(thisDict).ptr(), true);
        changed = true;
    }

    return changed;
}



// List of indices into thisKeys
labelList findMatches
(
    const HashTable<wordList, word>& shortcuts,
    const wordList& shortcutNames,
    const wordList& thisKeys,
    const keyType& key
)
{
    labelList matches;

    if (key.isPattern())
    {
        // Wildcard match
        matches = findStrings(key, thisKeys);

    }
    else if (shortcuts.size())
    {
        // See if patchGroups expand to valid thisKeys
        labelList indices = findStrings(key, shortcutNames);
        forAll(indices, i)
        {
            const word& name = shortcutNames[indices[i]];
            const wordList& keys = shortcuts[name];
            forAll(keys, j)
            {
                label index = findIndex(thisKeys, keys[j]);
                if (index != -1)
                {
                    matches.append(index);
                }
            }
        }
    }
    return matches;
}


// Dictionary merging/editing.
// literalRE:
// - true: behave like dictionary::merge, i.e. add regexps just like
//   any other key.
// - false : interpret wildcard as a rule for items to be matched.
bool merge
(
    dictionary& thisDict,
    const dictionary& mergeDict,
    const bool literalRE,
    const HashTable<wordList, word>& shortcuts
)
{
    const wordList shortcutNames(shortcuts.toc());

    bool changed = false;

    // Save current (non-wildcard) keys before adding items.
    HashSet<word> thisKeysSet;
    {
        List<keyType> keys = thisDict.keys(false);
        forAll(keys, i)
        {
            thisKeysSet.insert(keys[i]);
        }
    }

    // Pass 1. All literal matches

    forAllConstIter(IDLList<entry>, mergeDict, mergeIter)
    {
        const keyType& key = mergeIter().keyword();

        if (key[0] == '~')
        {
            word eraseKey = key(1, key.size()-1);
            if (thisDict.remove(eraseKey))
            {
                // Mark thisDict entry as having been match for wildcard
                // handling later on.
                thisKeysSet.erase(eraseKey);
            }
            changed = true;
        }
        else if (literalRE || !(key.isPattern() || shortcuts.found(key)))
        {
            entry* entryPtr = thisDict.lookupEntryPtr
            (
                key,
                false,              // recursive
                false               // patternMatch
            );

            if (entryPtr)
            {
                // Mark thisDict entry as having been match for wildcard
                // handling later on.
                thisKeysSet.erase(entryPtr->keyword());

                if
                (
                    addEntry
                    (
                        thisDict,
                       *entryPtr,
                        mergeIter(),
                        literalRE,
                        shortcuts
                    )
                )
                {
                    changed = true;
                }
            }
            else
            {
                // not found - just add
                thisDict.add(mergeIter().clone(thisDict).ptr());
                changed = true;
            }
        }
    }


    // Pass 2. Wildcard or shortcut matches (if any) on any non-match keys.

    if (!literalRE && thisKeysSet.size() > 0)
    {
        // Pick up remaining dictionary entries
        wordList thisKeys(thisKeysSet.toc());

        forAllConstIter(IDLList<entry>, mergeDict, mergeIter)
        {
            const keyType& key = mergeIter().keyword();

            if (key[0] == '~')
            {
                word eraseKey = key(1, key.size()-1);

                // List of indices into thisKeys
                labelList matches
                (
                    findMatches
                    (
                        shortcuts,
                        shortcutNames,
                        thisKeys,
                        eraseKey
                    )
                );

                // Remove all matches
                forAll(matches, i)
                {
                    const word& thisKey = thisKeys[matches[i]];
                    thisKeysSet.erase(thisKey);
                }
                changed = true;
            }
            else
            {
                // List of indices into thisKeys
                labelList matches
                (
                    findMatches
                    (
                        shortcuts,
                        shortcutNames,
                        thisKeys,
                        key
                    )
                );

                // Add all matches
                forAll(matches, i)
                {
                    const word& thisKey = thisKeys[matches[i]];

                    entry& thisEntry = const_cast<entry&>
                    (
                        thisDict.lookupEntry(thisKey, false, false)
                    );

                    if
                    (
                        addEntry
                        (
                            thisDict,
                            thisEntry,
                            mergeIter(),
                            literalRE,
                            HashTable<wordList, word>(0)    // no shortcuts
                                                            // at deeper levels
                        )
                    )
                    {
                        changed = true;
                    }
                }
            }
        }
    }

    return changed;
}



int main(int argc, char *argv[])
{
    #include "addDictOption.H"
    argList::addOption
    (
        "subDict",
        "name",
        "specify the subDict name of the replacements dictionary"
    );
    argList::addOption
    (
        "instance",
        "name",
        "override instance setting (default is the time name)"
    );

    // Add explicit time option
    timeSelector::addOptions();

    argList::addBoolOption
    (
        "literalRE",
        "treat regular expressions literally (i.e., as a keyword)"
    );
    argList::addBoolOption
    (
        "enableFunctionEntries",
        "enable expansion of dictionary directives - #include, #codeStream etc"
    );
    argList::addBoolOption
    (
        "disablePatchGroups",
        "disable matching keys to patch groups"
    );

    #include "addRegionOption.H"

    #include "setRootCase.H"
    #include "createTime.H"

    // Optionally override controlDict time with -time options
    instantList times = timeSelector::selectIfPresent(runTime, args);
    if (times.size() < 1)
    {
        FatalErrorInFunction
            << "No times selected." << exit(FatalError);
    }
    runTime.setTime(times[0], 0);
    word instance = args.optionLookupOrDefault("instance", runTime.timeName());

    #include "createNamedMesh.H"

    const bool literalRE = args.optionFound("literalRE");
    if (literalRE)
    {
        Info<< "Not interpreting any regular expressions (RE)"
            << " in the changeDictionaryDict." << endl
            << "Instead they are handled as any other entry, i.e. added if"
            << " not present." << endl;
    }

    const bool enableEntries = args.optionFound("enableFunctionEntries");
    if (enableEntries)
    {
        Info<< "Allowing dictionary preprocessing ('#include', '#codeStream')."
            << endl;
    }

    int oldFlag = entry::disableFunctionEntries;
    if (!enableEntries)
    {
        // By default disable dictionary expansion for fields
        entry::disableFunctionEntries = 1;
    }


    const bool disablePatchGroups = args.optionFound("disablePatchGroups");
    if (disablePatchGroups)
    {
        Info<< "Not interpreting any keys in the changeDictionary"
            << " as patchGroups"
            << endl;
    }


    fileName regionPrefix = "";
    if (regionName != fvMesh::defaultRegion)
    {
        regionPrefix = regionName;
    }


    // Make sure we do not use the master-only reading since we read
    // fields (different per processor) as dictionaries.
    regIOobject::fileModificationChecking = regIOobject::timeStamp;


    // Get the replacement rules from a dictionary

    const word dictName("changeDictionaryDict");
    #include "setSystemMeshDictionaryIO.H"
    IOdictionary dict(dictIO);

    const dictionary* replaceDictsPtr = &dict;

    if (args.optionFound("subDict"))
    {
        word subDictName(args.optionLookup("subDict")());
        replaceDictsPtr = &dict.subDict(subDictName);
    }

    const dictionary& replaceDicts = *replaceDictsPtr;

    Info<< "Read dictionary " << dict.name()
        << " with replacements for dictionaries "
        << replaceDicts.toc() << endl;



    // Always read boundary to get patch groups
    // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    Info<< "Reading polyMesh/boundary file to extract patch names"
        << endl;

    // Read PtrList of dictionary as dictionary.
    const word oldTypeName = IOPtrList<entry>::typeName;
    const_cast<word&>(IOPtrList<entry>::typeName) = word::null;
    IOPtrList<entry> dictList
    (
        IOobject
        (
            "boundary",
            runTime.findInstance
            (
                regionPrefix/polyMesh::meshSubDir,
                "boundary",
                IOobject::READ_IF_PRESENT
            ),
            polyMesh::meshSubDir,
            mesh,
            IOobject::READ_IF_PRESENT,
            IOobject::NO_WRITE,
            false
        )
    );
    const_cast<word&>(IOPtrList<entry>::typeName) = oldTypeName;

    // Fake type back to what was in field
    const_cast<word&>(dictList.type()) = dictList.headerClassName();

    // Temporary convert to dictionary
    dictionary fieldDict;
    forAll(dictList, i)
    {
        fieldDict.add(dictList[i].keyword(), dictList[i].dict());
    }

    if (dictList.size())
    {
        Info<< "Loaded dictionary " << dictList.name()
            << " with entries " << fieldDict.toc() << endl;
    }

    // Extract any patchGroups information (= shortcut for set of
    // patches)
    HashTable<wordList, word> patchGroups;
    if (!disablePatchGroups)
    {
        patchGroups = extractPatchGroups(fieldDict);
        if (patchGroups.size())
        {
            Info<< "Extracted patch groups:" << endl;
            wordList groups(patchGroups.sortedToc());
            forAll(groups, i)
            {
                Info<< "    group " << groups[i] << " with patches "
                    << patchGroups[groups[i]] << endl;
            }
        }
    }


    // Every replacement is a dictionary name and a keyword in this

    forAllConstIter(dictionary, replaceDicts, fieldIter)
    {
        const word& fieldName = fieldIter().keyword();
        Info<< "Replacing entries in dictionary " << fieldName << endl;

        // Handle 'boundary' specially:
        // - is PtrList of dictionaries
        // - is in polyMesh/
        if (fieldName == "boundary")
        {
            Info<< "Special handling of " << fieldName
                << " as polyMesh/boundary file." << endl;

            // Get the replacement dictionary for the field
            const dictionary& replaceDict = fieldIter().dict();
            Info<< "Merging entries from " << replaceDict.toc() << endl;

            // Merge the replacements in
            merge(fieldDict, replaceDict, literalRE, patchGroups);

            Info<< "fieldDict:" << fieldDict << endl;

            // Convert back into dictList
            wordList doneKeys(dictList.size());

            label nEntries = fieldDict.size();

            forAll(dictList, i)
            {
                doneKeys[i] = dictList[i].keyword();
                dictList.set
                (
                    i,
                    fieldDict.lookupEntry
                    (
                        doneKeys[i],
                        false,
                        true
                    ).clone()
                );
                fieldDict.remove(doneKeys[i]);
            }

            // Add remaining entries
            label sz = dictList.size();
            dictList.setSize(nEntries);
            forAllConstIter(dictionary, fieldDict, iter)
            {
                dictList.set(sz++, iter().clone());
            }

            Info<< "Writing modified " << fieldName << endl;
            dictList.writeObject
            (
                runTime.writeFormat(),
                runTime.writeFormat(),
                IOstream::UNCOMPRESSED
            );
        }
        else
        {
            // Read dictionary. (disable class type checking so we can load
            // field)
            Info<< "Loading dictionary " << fieldName << endl;
            const word oldTypeName = IOdictionary::typeName;
            const_cast<word&>(IOdictionary::typeName) = word::null;

            IOdictionary fieldDict
            (
                IOobject
                (
                    fieldName,
                    instance,
                    mesh,
                    IOobject::MUST_READ_IF_MODIFIED,
                    IOobject::NO_WRITE,
                    false
                )
            );

            const_cast<word&>(IOdictionary::typeName) = oldTypeName;

            // Fake type back to what was in field
            const_cast<word&>(fieldDict.type()) = fieldDict.headerClassName();

            Info<< "Loaded dictionary " << fieldName
                << " with entries " << fieldDict.toc() << endl;

            // Get the replacement dictionary for the field
            const dictionary& replaceDict = fieldIter().dict();
            Info<< "Merging entries from " << replaceDict.toc() << endl;

            // Merge the replacements in
            merge(fieldDict, replaceDict, literalRE, patchGroups);

            Info<< "Writing modified fieldDict " << fieldName << endl;
            fieldDict.regIOobject::write();
        }
    }

    entry::disableFunctionEntries = oldFlag;

    Info<< "\nEnd\n" << endl;

    return 0;
}


// ************************************************************************* //