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-module(chat).-compile(export_all).

startChat(Pong_Node) ->% Assigns to Ping_PID to process ID of ping% sends message to pong, passing Ping_PIDPing_PID = spawn(chat, ping, [Pong_Node]),{pong, Pong_Node} ! {ping, Ping_PID}.

ping(Pong_Node) ->% waits for messagereceive

{pong,Name1} ->

Name2=("someone: "),

% goes to pong's chatstart{pong, Pong_Node} ! chatstart,

% sends message to pong passing Name1,Name2, and PID ofping

{pong, Pong_Node} ! {Name1,Name2,self()},

% goes back to pingping(Pong_Node);

{Name1,Name2,Msg1} ->% prints the followingio:format("You: "),io:format("~s", [Msg1]),

Bye="bye\n",Val=Msg1=:=Bye,

% compare the message from the user with bye

case Val oftrue ->% if equal, sends message to pong passing bye, a

nd terminates chat after 5 seconds{pong, Pong_Node} ! bye,timer:sleep(3000),io:format("~n Your partner disconnected. ~n Ok~n

", []);false ->

% if not equal, gets another message from userMsg2 = io:get_line(Name2),

% sends message to pong passing Name1,Name2, new

message and PID of ping{pong, Pong_Node} ! {Name1,Name2,Msg2,self()},

% goes back to pingping(Pong_Node)

end;

bye ->% sends message to pong passing bye, and terminates ping

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after 5 seconds{pong, Pong_Node} ! bye,timer:sleep(3000),io:format("~nOk~n", [])

end.

pong()->% waits for messagereceive

{ping, Ping_PID} ->% sends message to ping, passing pongPing_PID ! pong,

% gets name, remove new line and add ">>"Name1=("You: "),

% sends message to ping, passing pong and Name1Ping_PID ! {pong,Name1},pong();

chatstart ->pong();

{Name1, Name2, Ping_PID} ->% gets the chat message from userMsg1 = io:get_line(Name1),% sends message to ping passing Name1,Name2,and message

from userPing_PID ! {Name1,Name2,Msg1},% goes back to pongpong();

{Name1, Name2, Msg2, Ping_PID} ->

% prints the followingio:format("someone: "),io:format("~s", [Msg2]),

Bye2="bye\n",Val=Msg2=:=Bye2,

% compare the message from the user with byecase Val oftrue ->

% if equal, sends message to ping passing byePing_PID ! bye,

% goes back to pongpong();

false ->% if not equal, get another message from userMsg1 = io:get_line(Name1),

% sends message to ping passing Name1,Name2 andnew message

Ping_PID ! {Name1,Name2,Msg1},

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% goes back to pongpong()

end;

bye->% waits for 3 seconds, and prints the following.timer:sleep(3000),io:format("~nok~n", [])% pong finished

end.

init_chat() ->register(pong, spawn(chat, pong, [])).

init_chat2(Pong_Node) ->spawn(chat, startChat, [Pong_Node]).