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%% Copyright Ericsson AB 1996-2018. All Rights Reserved.
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%% Licensed under the Apache License, Version 2.0 (the "License");
%% you may not use this file except in compliance with the License.
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%%     http://www.apache.org/licenses/LICENSE-2.0
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%% distributed under the License is distributed on an "AS IS" BASIS,
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-module(gradualizer_type).

-export_type([abstract_expr/0,
              abstract_clause/0,
              abstract_type/0]).

%% Export the additional types that gradualizer uses
-export_type([abstract_pattern/0]).

%% Start of Abstract Format

-type anno() :: erl_anno:anno().

-type abstract_expr() :: af_literal()
                       | af_match(abstract_expr())
                       | af_variable()
                       | af_tuple(abstract_expr())
                       | af_nil()
                       | af_cons(abstract_expr())
                       | af_bin(abstract_expr())
                       | af_binary_op(abstract_expr())
                       | af_unary_op(abstract_expr())
                       | af_record_creation(abstract_expr())
                       | af_record_update(abstract_expr())
                       | af_record_index()
                       | af_record_field_access(abstract_expr())
                       | af_map_creation(abstract_expr())
                       | af_map_update(abstract_expr())
                       | af_catch()
                       | af_local_call()
                       | af_remote_call()
                       | af_list_comprehension()
                       | af_binary_comprehension()
                       | af_block()
                       | af_if()
                       | af_case()
                       | af_try()
                       | af_receive()
                       | af_local_fun()
                       | af_remote_fun()
                       | af_fun()
                       | af_named_fun().

-type abstract_clause() :: af_clause().
-type abstract_pattern() :: af_pattern().

-type af_record_update(T) :: {'record',
                              anno(),
                              abstract_expr(),
                              record_name(),
                              [af_record_field(T)]}.

-type af_catch() :: {'catch', anno(), abstract_expr()}.

-type af_local_call() :: {'call', anno(), af_local_function(), af_args()}.

-type af_remote_call() :: {'call', anno(), af_remote_function(), af_args()}.

-type af_args() :: [abstract_expr()].

-type af_local_function() :: abstract_expr().

-type af_remote_function() ::
        {'remote', anno(), abstract_expr(), abstract_expr()}.

-type af_list_comprehension() ::
        {'lc', anno(), af_template(), af_qualifier_seq()}.

-type af_binary_comprehension() ::
        {'bc', anno(), af_template(), af_qualifier_seq()}.

-type af_template() :: abstract_expr().

-type af_qualifier_seq() :: [af_qualifier()].

-type af_qualifier() :: af_generator() | af_filter().

-type af_generator() :: {'generate', anno(), af_pattern(), abstract_expr()}
                      | {'b_generate', anno(), af_pattern(), abstract_expr()}.

-type af_filter() :: abstract_expr().

-type af_block() :: {'block', anno(), af_body()}.

-type af_if() :: {'if', anno(), af_clause_seq()}.

-type af_case() :: {'case', anno(), abstract_expr(), af_clause_seq()}.

-type af_try() :: {'try',
                   anno(),
                   af_body() | [],
                   af_clause_seq() | [],
                   af_clause_seq() | [],
                   af_body() | []}.

-type af_clause_seq() :: [af_clause(), ...].

-type af_receive() ::
        {'receive', anno(), af_clause_seq()}
      | {'receive', anno(), af_clause_seq(), abstract_expr(), af_body()}.

-type af_local_fun() ::
        {'fun', anno(), {'function', function_name(), arity()}}.

-type af_remote_fun() ::
        {'fun', anno(), {'function', module(), function_name(), arity()}}
      | {'fun', anno(), {'function', af_atom(), af_atom(), af_integer()}}.

-type af_fun() :: {'fun', anno(), {'clauses', af_clause_seq()}}.

-type af_named_fun() :: {'named_fun', anno(), fun_name(), af_clause_seq()}.

-type fun_name() :: atom().

-type af_clause() ::
        {'clause', anno(), [af_pattern()], af_guard_seq(), af_body()}.

-type af_body() :: [abstract_expr(), ...].

-type af_guard_seq() :: [af_guard()].

-type af_guard() :: [af_guard_test(), ...].

-type af_guard_test() :: af_literal()
                       | af_variable()
                       | af_tuple(af_guard_test())
                       | af_nil()
                       | af_cons(af_guard_test())
                       | af_bin(af_guard_test())
                       | af_binary_op(af_guard_test())
                       | af_unary_op(af_guard_test())
                       | af_record_creation(af_guard_test())
                       | af_record_index()
                       | af_record_field_access(af_guard_test())
                       | af_map_creation(abstract_expr())
                       | af_map_update(abstract_expr())
                       | af_guard_call()
                       | af_remote_guard_call().

-type af_record_field_access(T) ::
        {'record_field', anno(), T, record_name(), af_field_name()}.

-type af_map_creation(T) :: {'map', anno(), [af_assoc(T)]}.

-type af_map_update(T) :: {'map', anno(), T, [af_assoc(T)]}.

-type af_assoc(T) :: {'map_field_assoc', anno(), T, T}
                   | af_assoc_exact(T).

-type af_assoc_exact(T) :: {'map_field_exact', anno(), T, T}.

-type af_guard_call() :: {'call', anno(), function_name(), [af_guard_test()]}.

-type af_remote_guard_call() ::
        {'call', anno(),
         {'remote', anno(), af_lit_atom('erlang'), af_atom()},
         [af_guard_test()]}.

-type af_pattern() :: af_literal()
                    | af_match(af_pattern())
                    | af_variable()
                    | af_tuple(af_pattern())
                    | af_nil()
                    | af_cons(af_pattern())
                    | af_bin(af_pattern())
                    | af_binary_op(af_pattern())
                    | af_unary_op(af_pattern())
                    | af_record_creation(af_pattern())
                    | af_record_index()
                    | af_map_pattern().

-type af_record_index() ::
        {'record_index', anno(), record_name(), af_field_name()}.

-type af_record_creation(T) ::
        {'record', anno(), record_name(), [af_record_field(T)]}.

-type af_record_field(T) :: {'record_field', anno(), af_field_name(), T}.

-type af_map_pattern() ::
        {'map', anno(), [af_assoc_exact(abstract_expr())]}.

-type abstract_type() :: af_annotated_type()
                       | af_atom()
                       | af_bitstring_type()
                       | af_empty_list_type()
                       | af_fun_type()
                       | af_integer_range_type()
                       | af_map_type()
                       | af_predefined_type()
                       | af_record_type()
                       | af_remote_type()
                       | af_singleton_integer_type()
                       | af_tuple_type()
                       | af_type_union()
                       | af_type_variable()
                       | af_user_defined_type().

-type af_annotated_type() ::
        {'ann_type', anno(), [af_anno() | abstract_type()]}. % [Var, Type]

-type af_anno() :: af_variable().

-type af_bitstring_type() ::
        {'type', anno(), 'binary', [af_singleton_integer_type()]}.

-type af_empty_list_type() :: {'type', anno(), 'nil', []}.

-type af_fun_type() :: {'type', anno(), 'fun', []}
                     | {'type', anno(), 'fun', [{'type', anno(), 'any'} |
                                                abstract_type()]}
                     | af_function_type().

-type af_integer_range_type() ::
        {'type', anno(), 'range', [af_range_integer_type()]}.

-type af_map_type() :: {'type', anno(), 'map', 'any'}
                     | {'type', anno(), 'map', [af_assoc_type()]}.

-type af_assoc_type() ::
        {'type', anno(), 'map_field_assoc', [abstract_type()]}
      | {'type', anno(), 'map_field_exact', [abstract_type()]}.

-type af_predefined_type() ::
        {'type', anno(), type_name(),  [abstract_type()]}.

-type af_record_type() ::
        {'type', anno(), 'record', [(Name :: af_atom()) % [Name, T1, ... Tk]
                                    | af_record_field_type()]}.

-type af_record_field_type() ::
        {'type', anno(), 'field_type', [(Name :: af_atom()) |
                                        abstract_type()]}. % [Name, Type]

-type af_remote_type() ::
        {'remote_type', anno(), [(Module :: af_atom()) |
                                 (TypeName :: af_atom()) |
                                 [abstract_type()]]}. % [Module, Name, [T]]

-type af_tuple_type() :: {'type', anno(), 'tuple', 'any'}
                       | {'type', anno(), 'tuple', [abstract_type()]}.

-type af_type_union() :: {'type', anno(), 'union', [abstract_type()]}.

-type af_type_variable() :: {'var', anno(), atom()}. % except '_'

-type af_user_defined_type() ::
        {'user_type', anno(), type_name(),  [abstract_type()]}.

-type af_function_type() ::
        {'type', anno(), 'fun',
         [{'type', anno(), 'product', [abstract_type()]} | abstract_type()]}.

-type af_range_integer_type() :: 'pos_inf' | 'neg_inf'
                               | af_singleton_integer_type().

-type af_singleton_integer_type() :: af_integer()
                                   | af_character()
                                   | af_unary_op(af_singleton_integer_type())
                                   | af_binary_op(af_singleton_integer_type()).

-type af_literal() :: af_atom()
                    | af_character()
                    | af_float()
                    | af_integer()
                    | af_string().

-type af_atom() :: af_lit_atom(atom()).

-type af_lit_atom(A) :: {'atom', anno(), A}.

-type af_character() :: {'char', anno(), char()}.

-type af_float() :: {'float', anno(), float()}.

-type af_integer() :: {'integer', anno(), non_neg_integer()}.

-type af_string() :: {'string', anno(), string()}.

-type af_match(T) :: {'match', anno(), af_pattern(), T}.

-type af_variable() :: {'var', anno(), atom()}. % | af_anon_variable()

%-type af_anon_variable() :: {'var', anno(), '_'}.

-type af_tuple(T) :: {'tuple', anno(), [T]}.

-type af_nil() :: {'nil', anno()}.

-type af_cons(T) :: {'cons', anno(), T, T}.

-type af_bin(T) :: {'bin', anno(), [af_binelement(T)]}.

-type af_binelement(T) :: {'bin_element',
                           anno(),
                           T,
                           af_binelement_size(),
                           type_specifier_list()}.

-type af_binelement_size() :: 'default' | abstract_expr().

-type af_binary_op(T) :: {'op', anno(), binary_op(), T, T}.

-type binary_op() :: '/' | '*' | 'div' | 'rem' | 'band' | 'and' | '+' | '-'
                   | 'bor' | 'bxor' | 'bsl' | 'bsr' | 'or' | 'xor' | '++'
                   | '--' | '==' | '/=' | '=<' | '<'  | '>=' | '>' | '=:='
                   | '=/='.

-type af_unary_op(T) :: {'op', anno(), unary_op(), T}.

-type unary_op() :: '+' | '-' | 'bnot' | 'not'.

%% See also lib/stdlib/{src/erl_bits.erl,include/erl_bits.hrl}.
-type type_specifier_list() :: 'default' | [type_specifier(), ...].

-type type_specifier() :: type()
                        | signedness()
                        | endianness()
                        | unit().

-type type() :: 'integer'
              | 'float'
              | 'binary'
              | 'bytes'
              | 'bitstring'
              | 'bits'
              | 'utf8'
              | 'utf16'
              | 'utf32'.

-type signedness() :: 'signed' | 'unsigned'.

-type endianness() :: 'big' | 'little' | 'native'.

-type unit() :: {'unit', 1..256}.

-type record_name() :: atom().

-type af_field_name() :: af_atom().

-type function_name() :: atom().

-type type_name() :: atom().

%% End of Abstract Format