(*funkcija drugega prehoda*)
open Simtab
open SemanticAnalyzer
open Encoder
open Instruction
open OpcodeTable

let drugiPrehod (ifl : lineSemantic list) (simtab : symtab) (opcodeTab : opcodeTab) (lenProg : int) : string list = 
  let prviUkaz, ostaliUkazi = 
    match ifl with
    | [] -> failwith "empty code"
    | x :: xs -> x, xs
  in
    (*if Opcode == start then*)
  let objectCodeList, start = (*string list ki hrani vrstice objektne kode, start se uporabi še v E zapisu*) 
    if prviUkaz.opcode = START then
      getZaglavjeAndStart prviUkaz lenProg
    else
      failwith "prvi ukaz ni START"
  in
  let instructionList : string list = [] in (*instructionList shranjuje kode ukazov pretvorjene v stringe, ko se napolni se appenda k objectCodeList*)
  let rec loop (ostaliUkazi : lineSemantic list) (objectCodeList : string list) (startAddr : int) (instructionList : string list) : string list = 
    match ostaliUkazi with
    | [] -> failwith "no END mnemonic at the end of the code!"
    | x :: _ when x.opcode = END -> (*write last text record to object programm*)
      let newTextLine = instructionList_to_objectCode (List.rev instructionList) startAddr in (*naredimo novo T vrstico*)
      let endLine = getEnd start in (*naredimo End zapis*)
      let objectCodeList = List.rev (endLine :: newTextLine :: objectCodeList) in 
      objectCodeList (*vrnemo celotno objektno kodo*)
    | x :: xs -> 
      (*pridobi začeten naslov TEXT vrstice, če je le ta prazna*)
      let newStartAddress = match instructionList with
      | [] -> begin match x.loc with None -> failwith "ukaz nima lokacije!" | Some l -> l end 
      | _ -> startAddr
      in
      match x.opcode with
      | COMMENT -> loop xs objectCodeList newStartAddress instructionList 
      | RESB | RESW -> (*dodamo trenutno TEXT vrstico k objektni kodi in inicializiramo novo*)
        let newTextLine = instructionList_to_objectCode (List.rev instructionList) newStartAddress in (*naredimo novo T vrstico*)
        begin
        match instructionList with (*če je instructionList prazen, npr. 2 zaporedna RESB ukaza, ne dodamo te prazne T vrstice v obj kodo*)
        | [] -> loop xs objectCodeList newStartAddress []
        | _ -> loop xs (newTextLine :: objectCodeList) newStartAddress []
        end
      | BYTE -> 
        let operand = match x.mnem with | MnemonicSd s -> s | _ -> failwith "narobe mnemType za BYTE" in
        let opcode = create_opcode_byte operand in
        (*dodaj opcode v line, ce ni prostora dodaj line v file in naredi novega*)
        if List.length instructionList > 25 then (*če ratuje T zapis predolg dodamo še tole in nato nadaljujemo z novim*)
          let newTextLine = instructionList_to_objectCode (List.rev (opcode :: instructionList)) newStartAddress in (*naredimo novo T vrstico*)
          loop xs (newTextLine :: objectCodeList) newStartAddress []
        else
          loop xs objectCodeList newStartAddress (opcode :: instructionList)
      | WORD ->
        let operand = match x.mnem with | MnemonicSd s -> s | _ -> failwith "narobe mnemType za WORD" in
        let opcode = create_opcode_word operand in
        (*dodaj opcode v line, ce ni prostora dodaj line v file in naredi novega*)
        if List.length instructionList > 25 then (*če ratuje T zapis predolg dodamo še tole in nato nadaljujemo z novim*)
          let newTextLine = instructionList_to_objectCode (List.rev (opcode :: instructionList)) newStartAddress in (*naredimo novo T vrstico*)
          loop xs (newTextLine :: objectCodeList) newStartAddress []
        else
          loop xs objectCodeList newStartAddress (opcode :: instructionList)       
      | _ -> (*if not comment or reserve*)
          (*if simbol na mestu opeanda*)
        match operand_is_symbol x with
        | None -> loop xs objectCodeList newStartAddress instructionList (*None -> ta ukaz se ne zapiše, ga skipamo*)
        | Some (_, operand, formatLen) -> 
            let opcode = create_opcode simtab opcodeTab x.opcode operand formatLen x.loc in
            (*dodaj opcode v line, ce ni prostora dodaj line v file in naredi novega*)
            if List.length instructionList > 25 then (*če ratuje T zapis predolg dodamo še tole in nato nadaljujemo z novim*)
              let newTextLine = instructionList_to_objectCode (List.rev (opcode :: instructionList)) newStartAddress in (*naredimo novo T vrstico*)
              loop xs (newTextLine :: objectCodeList) newStartAddress []
            else
              loop xs objectCodeList newStartAddress (opcode :: instructionList)

  in loop ostaliUkazi objectCodeList start instructionList