// Copyright 2016 PDFium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com

#include "xfa/fde/css/fde_cssstyleselector.h"

#include <algorithm>
#include <memory>

#include "xfa/fde/css/fde_csscache.h"
#include "xfa/fde/css/fde_cssdeclaration.h"
#include "xfa/fde/css/fde_cssstylesheet.h"
#include "xfa/fde/css/fde_csssyntax.h"
#include "xfa/fxfa/app/xfa_textlayout.h"

#define FDE_CSSUNIVERSALHASH ('*')

void CFDE_CSSRuleCollection::Clear() {
  m_IDRules.RemoveAll();
  m_TagRules.RemoveAll();
  m_ClassRules.RemoveAll();
  m_pUniversalRules = nullptr;
  m_pStaticStore = nullptr;
  m_iSelectors = 0;
}

CFDE_CSSRuleCollection::CFDE_CSSRuleCollection()
    : m_pStaticStore(nullptr),
      m_pUniversalRules(nullptr),
      m_pPersudoRules(nullptr),
      m_iSelectors(0) {}

CFDE_CSSRuleCollection::~CFDE_CSSRuleCollection() {
  Clear();
}

void CFDE_CSSRuleCollection::AddRulesFrom(const CFDE_CSSStyleSheetArray& sheets,
                                          uint32_t dwMediaList,
                                          CFGAS_FontMgr* pFontMgr) {
  int32_t iSheets = sheets.GetSize();
  for (int32_t i = 0; i < iSheets; ++i) {
    IFDE_CSSStyleSheet* pSheet = sheets.GetAt(i);
    if (uint32_t dwMatchMedia = pSheet->GetMediaList() & dwMediaList) {
      int32_t iRules = pSheet->CountRules();
      for (int32_t j = 0; j < iRules; j++) {
        AddRulesFrom(pSheet, pSheet->GetRule(j), dwMatchMedia, pFontMgr);
      }
    }
  }
}

void CFDE_CSSRuleCollection::AddRulesFrom(IFDE_CSSStyleSheet* pStyleSheet,
                                          IFDE_CSSRule* pRule,
                                          uint32_t dwMediaList,
                                          CFGAS_FontMgr* pFontMgr) {
  switch (pRule->GetType()) {
    case FDE_CSSRULETYPE_Style: {
      IFDE_CSSStyleRule* pStyleRule = static_cast<IFDE_CSSStyleRule*>(pRule);
      CFDE_CSSDeclaration* pDeclaration = pStyleRule->GetDeclaration();
      int32_t iSelectors = pStyleRule->CountSelectorLists();
      for (int32_t i = 0; i < iSelectors; ++i) {
        CFDE_CSSSelector* pSelector = pStyleRule->GetSelectorList(i);
        if (pSelector->GetType() == FDE_CSSSELECTORTYPE_Persudo) {
          FDE_CSSRuleData* pData = NewRuleData(pSelector, pDeclaration);
          AddRuleTo(m_pPersudoRules, pData);
          continue;
        }
        if (pSelector->GetNameHash() != FDE_CSSUNIVERSALHASH) {
          AddRuleTo(m_TagRules, pSelector->GetNameHash(), pSelector,
                    pDeclaration);
          continue;
        }
        CFDE_CSSSelector* pNext = pSelector->GetNextSelector();
        if (!pNext) {
          FDE_CSSRuleData* pData = NewRuleData(pSelector, pDeclaration);
          AddRuleTo(m_pUniversalRules, pData);
          continue;
        }
        switch (pNext->GetType()) {
          case FDE_CSSSELECTORTYPE_ID:
            AddRuleTo(m_IDRules, pNext->GetNameHash(), pSelector, pDeclaration);
            break;
          case FDE_CSSSELECTORTYPE_Class:
            AddRuleTo(m_ClassRules, pNext->GetNameHash(), pSelector,
                      pDeclaration);
            break;
          case FDE_CSSSELECTORTYPE_Descendant:
          case FDE_CSSSELECTORTYPE_Element:
            AddRuleTo(m_pUniversalRules, NewRuleData(pSelector, pDeclaration));
            break;
          default:
            ASSERT(false);
            break;
        }
      }
    } break;
    case FDE_CSSRULETYPE_Media: {
      IFDE_CSSMediaRule* pMediaRule = static_cast<IFDE_CSSMediaRule*>(pRule);
      if (pMediaRule->GetMediaList() & dwMediaList) {
        int32_t iRules = pMediaRule->CountRules();
        for (int32_t i = 0; i < iRules; ++i) {
          AddRulesFrom(pStyleSheet, pMediaRule->GetRule(i), dwMediaList,
                       pFontMgr);
        }
      }
    } break;
    default:
      break;
  }
}

void CFDE_CSSRuleCollection::AddRuleTo(CFX_MapPtrToPtr& map,
                                       uint32_t dwKey,
                                       CFDE_CSSSelector* pSel,
                                       CFDE_CSSDeclaration* pDecl) {
  void* pKey = (void*)(uintptr_t)dwKey;
  FDE_CSSRuleData* pData = NewRuleData(pSel, pDecl);
  FDE_CSSRuleData* pList = nullptr;
  if (!map.Lookup(pKey, (void*&)pList)) {
    map.SetAt(pKey, pData);
  } else if (AddRuleTo(pList, pData)) {
    map.SetAt(pKey, pList);
  }
}

bool CFDE_CSSRuleCollection::AddRuleTo(FDE_CSSRuleData*& pList,
                                       FDE_CSSRuleData* pData) {
  if (pList) {
    pData->pNext = pList->pNext;
    pList->pNext = pData;
    return false;
  }

  pList = pData;
  return true;
}

FDE_CSSRuleData* CFDE_CSSRuleCollection::NewRuleData(
    CFDE_CSSSelector* pSel,
    CFDE_CSSDeclaration* pDecl) {
  return FXTARGET_NewWith(m_pStaticStore)
      FDE_CSSRuleData(pSel, pDecl, ++m_iSelectors);
}