{- Lazymail state, and operations on it.
 -
 - Copyright 2013 Raúl Benencia <rul@kalgan.cc>
 -
 - Licensed under the GNU GPL version 3 or higher
 -
 -}

module Lazymail.State where

import Codec.MIME.Type(MIMEValue, nullMIMEValue)
import Text.ParserCombinators.Parsec.Rfc2822(Message, GenericMessage(..))
import UI.NCurses(ColorID(..), defaultColorID)
import Network.Email.Mailbox(Flag(..), Flags)
import System.FilePath

import Lazymail.Types

initialState = LazymailState {
    mode          = MaildirMode
  , basePath      = ""
  , screenRows    = 0
  , screenColumns = 0
  , currentRow    = 0
  , columnPadding = 0
  , exitRequested = False
  , statusBar     = True
  , maildirState  = initialMaildirState
  , indexState    = initialIndexState
  , composeState  = initialComposeState
  , emailState    = initialEmailState
  , colorStyle    = initialColorStyle
}

initialMaildirState = MaildirState {
    selectedRowMD   = 0
  , selectedMD      = ""
  , detectedMDs     = []
  , scrollRowMD     = 0
  , scrollBufferMD  = []
  , triggerUpdateMD = False
}

initialIndexState = IndexState {
    selectedRowIn      = 0
  , selectedEmailPath  = ""
  , selectedEmails     = []
  , scrollRowIn        = 0
  , currentInLen       = 0
  , scrollBufferIn     = []
  , triggerUpdateIn    = False
}

initialEmailState = EmailState {
    scrollRowEm    = 0
  , bodyStartRow  = 0
  , emailLines     = []
  , currentEmail   = nullMIMEValue
}

initialComposeState = ComposeState {
    composition = Nothing
}

initialColorStyle = ColorStyle {
    baseColorID      = defaultColorID
  , selectionColorID = defaultColorID
  , statusBarColorID = defaultColorID
  , headerColorID    = defaultColorID
  , newEmailColorID  = defaultColorID
}

scrColsAsInteger st = toInteger $ screenColumns st
scrRowsAsInteger st = toInteger $ screenRows st
curRowAsInteger  st = toInteger $ currentRow st
colPadAsInteger  st = toInteger $ columnPadding st


incrementSelectedRow st | (selectedRow st) < limit =
  case (mode st) of
    MaildirMode ->
      let
        sr = (selectedRowMD . maildirState) st
        maildirState' = (maildirState st) { selectedRowMD = sr + 1 }
      in
       st { maildirState = maildirState' }
    IndexMode ->
      let
        sr = (selectedRowIn . indexState) st
        indexState' = (indexState st) { selectedRowIn = sr + 1 }
      in
       st { indexState = indexState' }
    _ -> st
                        | otherwise = st
  where
    scrRows = screenRows st
    curInLen = length $ selectedEmails . indexState $ st
    curMDLen = length $ detectedMDs . maildirState $ st
    limit' = case (mode st) of
      MaildirMode -> if curMDLen < scrRows then curMDLen - 1 else scrRows
      IndexMode   -> if curInLen < scrRows then curInLen - 1 else scrRows
    limit = if (statusBar st) && (limit' == scrRows)
            then fromIntegral $ limit' - 2
            else fromIntegral limit'

decrementSelectedRow st | (selectedRow st) > 0 =
  case (mode st) of
    MaildirMode ->
      let
        sr = (selectedRowMD . maildirState) st
        maildirState' = (maildirState st) { selectedRowMD = sr - 1 }
      in
       st { maildirState = maildirState' }
    IndexMode ->
      let
        sr = (selectedRowIn . indexState) st
        indexState' = (indexState st) { selectedRowIn = sr - 1 }
      in
       st { indexState = indexState' }
    _ -> st
                        | otherwise = st

selectedRow st = case (mode st) of
      MaildirMode -> selectedRowMD . maildirState $ st
      IndexMode   -> selectedRowIn . indexState   $ st