wxID_FINDNEXT = wx.wxID_HIGHEST + 20
wxID_FINDPREV = wx.wxID_HIGHEST + 30
wxID_REPLACE = wx.wxID_HIGHEST + 40
wxID_GOTOLINE = wx.wxID_HIGHEST + 50

editor           = nil

function createEditor(parent)
    editor = wxstc.wxStyledTextCtrl(parent, wx.wxID_ANY, wx.wxDefaultPosition, gui.EditFile:GetClientSize(), wx.wxSUNKEN_BORDER)

    local font
    local fontItalic
    if wx.wxPlatformWindows then
        font       = wx.wxFont(10, wx.wxNORMAL, wx.wxNORMAL, wx.wxNORMAL, false, "Andale Mono")
        fontItalic = wx.wxFont(10, wx.wxNORMAL, wx.wxFONTSTYLE_ITALIC, wx.wxNORMAL, false, "Andale Mono")
    else
        font       = wx.wxFont(12, wx.wxNORMAL, wx.wxNORMAL, wx.wxNORMAL, false, "lucidatypewriter")
        fontItalic = wx.wxFont(12, wx.wxNORMAL, wx.wxFONTSTYLE_ITALIC, wx.wxNORMAL, false, "lucidatypewriter")
    end
    editor:SetAutoLayout(true)
    editor:SetBufferedDraw(true)
    editor:SetFont(font)
    editor:StyleSetFont(wxstc.wxSTC_STYLE_DEFAULT, font)
    editor:StyleClearAll()
    editor:StyleSetForeground(0,  wx.wxColour(128, 128, 128))          -- White space
    editor:StyleSetForeground(1,  wx.wxColour(0, 127, 0))              -- Comment
    editor:StyleSetFont(1, fontItalic)
    editor:StyleSetUnderline(1, false)
    editor:StyleSetForeground(2,  wx.wxColour(0, 127, 0))              -- Line Comment
    editor:StyleSetFont(2, fontItalic)                                 -- Doc. Comment
    editor:StyleSetUnderline(2, false)
    editor:StyleSetForeground(3,  wx.wxColour(127, 127, 127))          -- Number
    editor:StyleSetForeground(4,  wx.wxColour(0, 127, 127))            -- Keyword
    editor:StyleSetForeground(5,  wx.wxColour(0, 0, 127))              -- Double quoted string
    editor:StyleSetBold(5,  true)
    editor:StyleSetUnderline(5, false)
    editor:StyleSetForeground(6,  wx.wxColour(127, 0, 127))            -- Single quoted string
    editor:StyleSetForeground(7,  wx.wxColour(127, 0, 127))            -- not used
    editor:StyleSetForeground(8,  wx.wxColour(0, 127, 127))            -- Literal strings
    editor:StyleSetForeground(9,  wx.wxColour(127, 127, 0))            -- Preprocessor
    editor:StyleSetForeground(10, wx.wxColour(0, 0, 0))                -- Operators
    editor:StyleSetBold(10, true)
    editor:StyleSetForeground(11, wx.wxColour(0, 0, 0))                -- Identifiers
    editor:StyleSetForeground(12, wx.wxColour(0, 0, 0))                -- Unterminated strings
    editor:StyleSetBackground(12, wx.wxColour(224, 192, 224))
    editor:StyleSetBold(12, true)
    editor:StyleSetEOLFilled(12, true)

    editor:StyleSetForeground(13, wx.wxColour(0, 0, 95))               -- Keyword highlighting styles
    editor:StyleSetForeground(14, wx.wxColour(0, 95, 0))
    editor:StyleSetForeground(15, wx.wxColour(127, 0, 0))
    editor:StyleSetForeground(16, wx.wxColour(127, 0, 95))
    editor:StyleSetForeground(17, wx.wxColour(63, 95, 95))

    editor:StyleSetForeground(18, wx.wxColour(0, 127, 127))            -- Nested literal strings ???
    editor:StyleSetBackground(18, wx.wxColour(240,255,255))
    editor:StyleSetForeground(19, wx.wxColour(0, 127, 127))
    editor:StyleSetBackground(19, wx.wxColour(224,255,255))
    editor:StyleSetForeground(20, wx.wxColour(0, 127, 127))
    editor:StyleSetBackground(20, wx.wxColour(192,255,255))
    editor:StyleSetForeground(21, wx.wxColour(0, 127, 127))
    editor:StyleSetBackground(21, wx.wxColour(176,255,255))
    editor:StyleSetForeground(22, wx.wxColour(0, 127, 127))
    editor:StyleSetBackground(22, wx.wxColour(160,255,255))
    editor:StyleSetForeground(23, wx.wxColour(0, 127, 127))
    editor:StyleSetBackground(23, wx.wxColour(144,255,255))
    editor:StyleSetForeground(24, wx.wxColour(0, 127, 127))
    editor:StyleSetBackground(24, wx.wxColour(128,155,255))

    editor:StyleSetForeground(32, wx.wxColour(224, 192, 224))          -- Line number
    editor:StyleSetBackground(33, wx.wxColour(192, 192, 192))          -- Brace highlight
    editor:StyleSetForeground(34, wx.wxColour(0, 0, 255))
    editor:StyleSetBold(34, true)                                   -- Brace incomplete highlight
    editor:StyleSetForeground(35, wx.wxColour(255, 0, 0))
    editor:StyleSetBold(35, true)                                   -- Indentation guides
    editor:StyleSetForeground(37, wx.wxColour(192, 192, 192))
    editor:StyleSetBackground(37, wx.wxColour(255, 255, 255))
    editor:SetUseTabs(false)
    editor:SetTabWidth(4)
    editor:SetIndent(4)
    editor:SetIndentationGuides(true)
    editor:SetMarginSensitive(1, true)
    editor:SetMarginWidth(1, 30)
    editor:SetMarginType(1, wxstc.wxSTC_MARGIN_NUMBER)
    editor:SetVisiblePolicy(wxstc.wxSTC_VISIBLE_SLOP, 3)
    editor:SetXCaretPolicy(wxstc.wxSTC_CARET_SLOP, 10)
    editor:SetYCaretPolicy(wxstc.wxSTC_CARET_SLOP, 3)
    editor:SetCaretLineVisible(true)

    editor:SetLexer(wxstc.wxSTC_LEX_LUA)
    editor:SetKeyWords(0,
        [[and break do else elseif end false for function if in
        local nil not or repeat return then true until while]])
    editor:SetKeyWords(1,
        [[_PROMPT _VERSION
        _G _VERSION assert collectgarbage dofile error gcinfo getfenv getmetatable
        ipairs loadfile loadlib loadstring next pairs pcall print rawequal
        rawget rawset require setfenv setmetatable tonumber tostring type unpack xpcall]])
    local Luakeywords = {}
    for i in pairs(math) do
        table.insert(Luakeywords, "math."..i.." ")
    end
    editor:SetKeyWords(2, table.concat(Luakeywords))
    Luakeywords = {}
    for i in pairs(coroutine) do
        table.insert(Luakeywords, "coroutine."..i.." ")
    end
    for i in pairs(debug) do
        table.insert(Luakeywords, "debug."..i.." ")
    end
    for i in pairs(io) do
        table.insert(Luakeywords, "io."..i.." ")
    end
    for i in pairs(os) do
        table.insert(Luakeywords, "os."..i.." ")
    end
    for i in pairs(string) do
        table.insert(Luakeywords, "string."..i.." ")
    end
    for i in pairs(table) do
        table.insert(Luakeywords, "table."..i.." ")
    end
    editor:SetKeyWords(3, table.concat(Luakeywords))
--    editor:SetKeyWords(5, [[
--        ]])
--    editor:SetKeyWords(6, [[
--        ]])

    editor:UsePopUp(false)

    parent:Connect(wx.wxID_ANY, wx.wxEVT_SIZE , function (event) 
        editor:SetSize(parent:GetClientSize())
    end)

    editor:Connect(wx.wxEVT_RIGHT_UP , function ( event )
        editMenu = wx.wxMenu{
                               { wx.wxID_UNDO,      "&Undo\tCtrl-Z",       "Undo the last action" },
                               { wx.wxID_REDO,      "&Redo\tCtrl-Y",       "Redo the last action undone" },
                               { },
                               { wx.wxID_CUT,       "Cu&t\tCtrl-X",        "Deletes selected text and copies it to clipboard" },
                               { wx.wxID_COPY,      "&Copy\tCtrl-C",       "Copies selected text to the clipboard" },
                               { wx.wxID_PASTE,     "&Paste\tCtrl-V",      "Inserts clipboard contents at the current location" },
                               { wx.wxID_CLEAR,     "D&elete\tDel",        "Deletes selected text without copying to the clipboard" },
                               { wx.wxID_SELECTALL, "Select &All\tCtrl-A", "Select all text in the editor" },
                               { },
                               { wx.wxID_FIND,    "&Find\tCtrl-F",            "Find the specified text" },
                               { wxID_FINDNEXT,   "Find &Next\tF3",           "Find the next occurrence of the specified text" },
                               { wxID_FINDPREV,   "Find &Previous\tShift-F3", "Repeat the search backwards in the file" },
                               { wxID_REPLACE,    "&Replace\tCtrl-H",         "Replaces the specified text with different text" },
                               { },
                               { wxID_GOTOLINE,   "&Goto line\tCtrl-G",       "Go to a selected line" }
                             }
        editor:PopupMenu(editMenu, event:GetPosition())
    end)

    editor:Connect(wx.wxEVT_KEY_DOWN, function(event) 
        local keycode = event:GetKeyCode()
        local ctrl = event:ControlDown()
        local shift = event:ShiftDown()
        if shift and keycode==wx.WXK_F3 then
            local commandEvent = wx.wxCommandEvent(wx.wxEVT_COMMAND_MENU_SELECTED, wxID_FINDPREV)
            wx.wxPostEvent(editor, commandEvent)
        elseif keycode==wx.WXK_F3 then
            local commandEvent = wx.wxCommandEvent(wx.wxEVT_COMMAND_MENU_SELECTED, wxID_FINDNEXT)
            wx.wxPostEvent(editor, commandEvent)
        elseif ctrl and keycode==72 then
            local commandEvent = wx.wxCommandEvent(wx.wxEVT_COMMAND_MENU_SELECTED, wxID_REPLACE)
            wx.wxPostEvent(editor, commandEvent)
        elseif ctrl and keycode==70 then
            local commandEvent = wx.wxCommandEvent(wx.wxEVT_COMMAND_MENU_SELECTED, wx.wxID_FIND)
            wx.wxPostEvent(editor, commandEvent)
        elseif ctrl and keycode==71 then
            local commandEvent = wx.wxCommandEvent(wx.wxEVT_COMMAND_MENU_SELECTED, wxID_GOTOLINE)
            wx.wxPostEvent(editor, commandEvent)
        end
        event:Skip()
    end)

editor:Connect(wx.wxID_UNDO,
                   wx.wxEVT_COMMAND_MENU_SELECTED,
                   function ( event )
                        editor:Undo()
                   end)

editor:Connect(wx.wxID_REDO,
                   wx.wxEVT_COMMAND_MENU_SELECTED,
                   function ( event )
                        editor:Redo()
                   end)

editor:Connect(wx.wxID_CUT,
                   wx.wxEVT_COMMAND_MENU_SELECTED,
                   function ( event )
                        editor:Cut()
                   end)

editor:Connect(wx.wxID_COPY,
                   wx.wxEVT_COMMAND_MENU_SELECTED,
                   function ( event )
                        editor:Copy()
                   end)

editor:Connect(wx.wxID_PASTE,
                   wx.wxEVT_COMMAND_MENU_SELECTED,
                   function ( event )
                        editor:Paste()
                   end)

editor:Connect(wx.wxID_CLEAR,
                   wx.wxEVT_COMMAND_MENU_SELECTED,
                   function ( event )
                        editor:Clear()
                   end)

editor:Connect(wx.wxID_SELECTALL,
                   wx.wxEVT_COMMAND_MENU_SELECTED,
                   function ( event )
                        editor:SelectAll()
                   end)                   

editor:Connect(wx.wxID_FIND,
                   wx.wxEVT_COMMAND_MENU_SELECTED,
                   function ( event )
                        findReplace(editor,false)
                   end)

editor:Connect(wxID_FINDNEXT,
                   wx.wxEVT_COMMAND_MENU_SELECTED,
                   function ( event )
                        if findData then
                            findText(1,
                                     findData:GetFindString(),
                                     findData:GetFlags())
                        end
                   end)

editor:Connect(wxID_FINDPREV,
                   wx.wxEVT_COMMAND_MENU_SELECTED,
                   function ( event )
                        if findData then
                           findText(2,
                                    findData:GetFindString(),
                                    findData:GetFlags())
                        end
                   end)

editor:Connect(wxID_REPLACE,
                   wx.wxEVT_COMMAND_MENU_SELECTED,
                   function ( event )
                        findReplace(editor,true)
                   end)

editor:Connect(wxID_GOTOLINE,
                   wx.wxEVT_COMMAND_MENU_SELECTED,
                   function ( event )
                        local linemax = editor:LineFromPosition(editor:GetLength()) + 1
                        local linenum = wx.wxGetNumberFromUser( "Enter line number",
                                                                "1 .. "..tostring(linemax),
                                                                "Goto Line",
                                                                1,
                                                                1,
                                                                linemax,
                                                                editor)
                        if linenum > 0 then
                            editor:GotoLine(linenum-1)
                        end
                   end)
end

function ensureRangeVisible(posStart, posEnd)
    if posStart > posEnd then
        posStart, posEnd = posEnd, posStart
    end

    local lineStart = editor:LineFromPosition(posStart)
    local lineEnd   = editor:LineFromPosition(posEnd)
    for line = lineStart, lineEnd do
        editor:EnsureVisibleEnforcePolicy(line)
    end
end

function setSearchFlags(editor, fWholeWord, fMatchCase)
    local flags = 0
    if fWholeWord then
        flags = wxstc.wxSTC_FIND_WHOLEWORD
    end
    if fMatchCase then
        flags = flags + wxstc.wxSTC_FIND_MATCHCASE
    end
    editor:SetSearchFlags(flags)
end

function findstring(strFind, fDown, fWholeWord, fMatchCase)
    local lenFind = string.len(strFind)
    if lenFind == 0 then
        return
    end
    local startSel      = editor:GetSelectionStart()
    local endSel        = editor:GetSelectionEnd()
    local startPosition = endSel
    local endPosition   = editor:GetLength()
    if not fDown then
        startPosition = startSel - 1
        endPosition   = 0
    end
    editor:SetTargetStart(startPosition)
    editor:SetTargetEnd(endPosition)
    setSearchFlags(editor, fWholeWord, fMatchCase)
    local posFind = editor:SearchInTarget(strFind)
    if posFind == -1 then
        if not fDown then
            startPosition = editor:GetLength()
            endPosition   = 0
        else
            startPosition = 0
            endPosition   = editor:GetLength()
        end
        editor:SetTargetStart(startPosition)
        editor:SetTargetEnd(endPosition)
        posFind = editor:SearchInTarget(strFind)
    end
    if posFind == -1 then
        fHaveFound = nil
    else
        fHaveFound = 1
        local start  = editor:GetTargetStart()
        local finish = editor:GetTargetEnd()
        ensureRangeVisible(start, finish)
        editor:SetSelection(start, finish)
    end
end

function replace(strFind, strReplace, fDown, fWholeWord, fMatchCase, fReplaceAll)
    local findLen = string.len(strFind)
    if findLen == 0 then
        return
    end

    if fReplaceAll then
        local startPosition = editor:GetSelectionStart()
        local endPosition   = editor:GetLength()
        local replaceLen    = string.len(strReplace)

        editor:SetTargetStart(startPosition)
        editor:SetTargetEnd(endPosition)
        setSearchFlags(editor, fWholeWord, fMatchCase)
        local posFind = editor:SearchInTarget(strFind)
        if (posFind ~= -1) and (posFind <= endPosition) then
            local lastMatch = posFind
            editor:BeginUndoAction()
            while posFind ~= -1 do
                local lenTarget = editor:GetTargetEnd() - editor:GetTargetStart()
                editor:ReplaceTarget(strReplace)

                endPosition = endPosition + replaceLen - lenTarget
                lastMatch = posFind + replaceLen

                if lenTarget <= 0 then
                    lastMatch = lastMatch + 1
                end

                editor:SetTargetStart(lastMatch)
                editor:SetTargetEnd(endPosition)
                posFind = editor:SearchInTarget(strFind)
            end
            editor:SetSelection(lastMatch, lastMatch)
            editor:EndUndoAction()
        end
    else
        if fHaveFound then
            local replaceLen = string.len(strReplace)
            local start  = editor:GetSelectionStart()
            local finish = editor:GetSelectionEnd()
            editor:SetTargetStart(start)
            editor:SetTargetEnd(finish)
            editor:ReplaceTarget(strReplace)
            editor:SetSelection(start + replaceLen, finish)
            fHaveFound = nil
        end

        findstring(strFind, fDown, fWholeWord, fMatchCase)
    end
end

function findText(where, strFind, findFlags)
    -- where == 2                  - Find previous
    -- where == 1                  - Find next
    -- where == 0 or where == nil  - Find

    local fDown, fWholeWord, fMatchCase

    if findFlags >= wx.wxFR_MATCHCASE then
        findFlags = findFlags - wx.wxFR_MATCHCASE
        fMatchCase = 1
    end
    if findFlags >= wx.wxFR_WHOLEWORD then
        findFlags = findFlags - wx.wxFR_WHOLEWORD
        fWholeWord = 1
    end
    if findFlags >= wx.wxFR_DOWN and where ~= 2 then
        fDown = 1
    end

    findstring(strFind, fDown, fWholeWord, fMatchCase)
end

function replaceText(where, strFind, strReplace, findFlags)
    -- where == 1                  - Replace all
    -- where == 0                  - Replace

    local fDown, fWholeWord, fMatchCase

    if findFlags >= wx.wxFR_MATCHCASE then
        findFlags = findFlags - wx.wxFR_MATCHCASE
        fMatchCase = 1
    end
    if findFlags >= wx.wxFR_WHOLEWORD then
        findFlags = findFlags - wx.wxFR_WHOLEWORD
        fWholeWord = 1
    end
    if findFlags >= wx.wxFR_DOWN and where ~= 2 then
        fDown = 1
    end

    replace(strFind, strReplace, fDown, fWholeWord, fMatchCase, where == 1)
end

function findReplace(editor,replace)
    if not findData then
        findData = wx.wxFindReplaceData(wx.wxFR_DOWN)
    end

    local flag
    local title

    if replace then
        flag  = wx.wxFR_REPLACEDIALOG
        title = "Replace"
    else
        flag  = 0
        title = "Find"
    end

    if not finddlg then
        finddlg = wx.wxFindReplaceDialog(editor,
                                           findData,
                                           title,
                                           flag)

        finddlg:Connect(wx.wxEVT_COMMAND_FIND,
                         function ( event )
                           findText(0,
                                    event:GetFindString(),
                                    event:GetFlags())
                         end)

        finddlg:Connect(wx.wxEVT_COMMAND_FIND_NEXT,
                         function ( event )
                           findText(1,
                                    event:GetFindString(),
                                    event:GetFlags())
                         end)

        finddlg:Connect(wx.wxEVT_COMMAND_FIND_REPLACE,
                         function ( event )
                            replaceText(0,
                                        event:GetFindString(),
                                        event:GetReplaceString(),
                                        event:GetFlags())
                         end)

        finddlg:Connect(wx.wxEVT_COMMAND_FIND_REPLACE_ALL,
                         function ( event )
                            replaceText(1,
                                        event:GetFindString(),
                                        event:GetReplaceString(),
                                        event:GetFlags())
                         end)

        finddlg:Connect(wx.wxEVT_COMMAND_FIND_CLOSE,
                         function ( event )
                           finddlg:Destroy()
                           finddlg = nil
                         end)

        finddlg:Show(true)
    end
end

function loadEditor(parent,filePath)
    if editor ~= nil then
        editor:Destroy()
        editor = nil
    end
    createEditor(parent)
    local handle = io.open(filePath, "rb")
    if handle then
        local st = handle:read("*a")
        handle:close()
        editor:Clear()
        editor:ClearAll()
        editor:InsertText(0, st)
        editor:EmptyUndoBuffer()
    end
    return editor
end

function saveEditor(filePath)
    local saved = false
    local st    = editor:GetText()
    local handle = io.open(filePath, "wb")
    if handle then
        handle:write(st)
        handle:close()
        editor:EmptyUndoBuffer()
        saved = true
    end
    return saved
end

function getTextEditor()
    local st    = ""
    if editor then
        st    = editor:GetText()
    end
    return st
end