Interpret the Pig series

Question

Given an input of a Pig, SickPig, DeadPig, QuinePig, or DeafPig program, choose one of those "languages" randomly and interpret the input as that "language."

First, randomly choose between one of the five members of the "Pig series":

• Pig

  If the choice was Pig, mimic the reference interpreter by doing the following:

  • Find the first occurrence of the word PIG in the input (case-sensitive).

  • If the word PIG does not appear in the input, output the message File must contain the string 'PIG'. and exit.

  • Otherwise, split the input string on the first occurrence of PIG. Output the text after the first occurrence of PIG to a file with a filename of the text before PIG.

    PIG may be contained in the text to be output (so, an input of fooPIGbarPIGbaz should output barPIGbaz to a file called foo).

  Note that the reference interpreter takes input via a command line argument that specifies a filename to read from. However, your submission may take input in any of the standard methods accepted on PPCG.

• SickPig

  If the choice was SickPig, follow the same instructions as Pig. However, instead of writing the text after PIG to the file, choose randomly from the following list

  GRUNT
  MOAN
  OINK
  BURP
  GROAN
  WHINE
  

  and output that to the file instead. This random choice must be independent of the previous choice (so, an output of GRUNT should have a 1/5 * 1/6 = 1/30 chance overall).

• DeadPig

  DeadPig is like SickPig, but it always outputs the following string instead of randomly choosing a string:

  Your pig has unfortunately died. Please try again.
  

• QuinePig

  QuinePig is like Pig, but instead of writing the text after PIG to the file, it instead writes the entire input to the file (so, an input of fooPIGbarPIGbaz should output fooPIGbarPIGbaz to a file called foo).

• DeafPig

  If the choice was DeafPig, do nothing. (The pig is deaf... what do you expect?)

Miscellaneous rules:

• "Random" means each choice should be roughly equally likely (so, choosing Pig 90% of the time and the other variants only 2.5% of the time is invalid).

• You may assume that the requested filenames will always be valid for your file system (but they may contain spaces, etc.).

• For all the variants of Pig, your code may optionally output a single trailing newline to the file as well.

• Since this is code-golf, the shortest code in bytes will win.

Answer 1

Bash, 251 246 bytes

r=$RANDOM
((r%5<4))||exit
[[ $1 =~ PIG ]]||(echo "File must contain the string 'PIG'.";exit)
s=(GRUNT MOAN OINK BURP GROAN WHINE)
m=("${1#*PIG}" ${s[r%6]}
"Your pig has unfortunately died. Please try again." "$1")
echo -n "${m[r%5]}">"${1%%PIG*}"

This would be a lot shorter if deaf pigs could at least read...

Answer 2

Python 2, 296 286 278 bytes

def g(p):
 import random;f=random.randint;r=f(0,4);i=p.find("PIG")
 if r:
    if i+1:open(p[:i],"w").write([0,p[i+3:],["GRUNT","MOAN","OINK","BURP","GROAN","WHINE"][f(0,5)],"Your pig has unfortunately died. Please try again.",p][r])
    else:print"File must contain the string 'PIG'."

The last two lines start with a tab, instead of the rendered 4 spaces.

Takes input program as function argument.

Answer 3

Batch, 409 406 405 bytes

@echo off
set/ar=%random%%%5
if 0==%r% exit/b
set p=x%1
set q=%p:*PIG=%
if %q%==%p% echo File must contain the string 'PIG'.&exit/b
set p=%1
call set p=%%p:PIG%q%=%%
goto %r%
:1
echo %q%>%p%
exit/b
:2
for %%a in (GRUNT.0 MOAN.1 OINK.2 BURP.3 GROAN.4 WHINE.5)do if %%~xa==.%time:~6,1% echo %%~na
exit/b
:3
echo Your pig has unfortunately died. Please try again.>%p%
exit/b
:4
echo %1>%p%

Sadly %p:*PIG=% fails if p is blank, thus the x%1 hack. call set is a nice way to avoid enabledelayedexpansion that I found on Stack Overflow; while the %%~xa==. was a flash of inspiration on my part.

Edit: Saved 3 bytes thanks to @CᴏɴᴏʀO'Bʀɪᴇɴ. Saved 1 byte thanks to @EʀɪᴋᴛʜᴇGᴏʟғᴇʀ.

Answer 4

Pyth - 157 bytes

Will be doing string compression.

?}J"PIG"z?=GO[jJtKczJOc"GRUNT MOAN OINK BURP GROAN WHINE"d"Your pig has unfortunately died. Please try again."z0).wGhK.q"File must contain the string 'PIG'."

Doesn't work online cuz of file I/O, but try it outputting [content, filename] to stdio here.