--------------------------------------------------------------------------------
-- Title:               MIME.lua
-- Description:         Like a square peg in a round hole
-- Author:              Raphaël Szwarc http://alt.textdrive.com/lua/
-- Creation Date:       February 1, 2005
-- Legal:               Copyright (C) 2005 Raphaël Szwarc
--------------------------------------------------------------------------------

-- import dependencies
local LUObject = require( "LUObject" )
local LUClass = require( "LUClass" )
local LUString = require( "LUString" )
local MIMEHeaders = require( "MIMEHeaders" )
local MIMEBase64 = require( "MIMEBase64" )
local MIMEQuotedPrintable = require( "MIMEQuotedPrintable" )

-- define the class
local super = LUObject
local self = super()

function self:init( aRawContent, aStartIndex, anEndIndex, aParent )
        self = super.init( self )

        self._rawContent = aRawContent
        self._startIndex = aStartIndex
        self._endIndex = anEndIndex
        self._parent = aParent

        return self
end

function self:rawContent()
        return self._rawContent
end

function self:startIndex()
        if self._startIndex == nil then
                self._startIndex = 1
        end

        return self._startIndex
end

function self:endIndex()
        if self._endIndex == nil then
                self._endIndex = self:rawContent():len()
        end

        return self._endIndex
end

function self:parent()
        return self._parent
end

function self:headers()
        if self._headers == nil then
                self._headers = MIMEHeaders( self:rawContent(), self:startIndex(), self:endIndex() )
        end
        
        return self._headers
end

function self:version()
        return ( self:headers():getValue( "mime-version" ) or "1.0" ):lower()
end

function self:type()
        return ( self:headers():getValue( "content-type" ) or "text/plain" ):lower()
end

function self:transferEncoding()
        return ( self:headers():getValue( "content-transfer-encoding" ) or "7bit" ):lower()
end

function self:id()
        return self:headers():getValue( "content-id" )
end

function self:description()
        return self:headers():getValue( "content-description" )
end

function self:disposition()
        return self:headers():getValue( "content-disposition" )
end

function self:entityWithType( aType )
        local aName = "MIME" .. LUString:capitalize( aType ):gsub( "[^%w]", "" )
        local aClass = LUClass:classWithName( aName )
        
        if aClass == nil then
                local anIndex = aType:find( "/", 1, true )
                
                if anIndex ~= nil then
                        aType = aType:sub( 1, anIndex - 1 )
                        aName = "MIME" .. LUString:capitalize( aType )
                        aClass = LUClass:classWithName( aName )
                end
        end
        
        if aClass ~= nil then
                return aClass:entity()
        end
        
        return nil
end

function self:content()
        if self._content == nil then
                local aType = self:type()
                local anEntity = self:entityWithType( aType )
                local aRawContent = self:rawContent()
                local aStart = self:headers():endIndex()
                local anEnd = self:endIndex()
                
                if anEntity == nil then
                        local aContent = aRawContent:sub( aStart, anEnd )
                        local anEncoding = self:transferEncoding()
                                                
                        if anEncoding == "quoted-printable" then
                                aContent = MIMEQuotedPrintable:decode( aContent )
                        elseif anEncoding == "base64" then
                                aContent = MIMEBase64:decode( aContent )
                        end
                        
                        self._content = aContent
                else
                        self._content = anEntity( aRawContent, aStart, anEnd, self )
                end
        end
        
        return self._content
end

return self