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+/*
+ * richard-atp-engine: A saturation-based automated theorem prover for first-order logic.
+ * Copyright (C) 2026 Richard Qin
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+/// @file tptp_parser.h
+/// @brief TPTP format parser — converts .p files to internal representations.
+///
+/// The parser interns all symbols (predicates, functions, variables) into the
+/// SymbolTable and builds terms in the TermBank during parsing. This is the
+/// E Prover approach: parse and intern simultaneously, avoiding a separate
+/// resolution pass.
+///
+/// V1: Hand-written recursive descent for TPTP CNF/FOF subset.
+///     (ANTLR4 integration deferred — avoids build complexity for V1.)
+
+#include "atp/core/clause.h"
+#include "atp/core/symbol_table.h"
+#include "atp/core/term_bank.h"
+#include "atp/normalize/formula.h"
+
+#include <string>
+#include <vector>
+
+namespace atp {
+
+/// Role of a TPTP formula.
+/// See TPTP spec: https://www.tptp.org/TPTP/SyntaxBNF.html
+enum class FormulaRole : uint8_t {
+    kAxiom,              ///< Background truth
+    kHypothesis,         ///< Problem-specific assumption
+    kDefinition,         ///< Symbol definition (can be unfolded)
+    kAssumption,         ///< Assumed for this proof attempt
+    kLemma,              ///< Derived intermediate result
+    kTheorem,            ///< Previously proved statement (used as axiom)
+    kConjecture,         ///< The statement to prove
+    kNegatedConjecture,  ///< Already negated conjecture (input was cnf)
+    kPlain,              ///< No semantic role specified
+};
+
+/// Map a TPTP role string to enum. Returns kPlain for unknown roles.
+FormulaRole parseRole(std::string_view role_str);
+
+/// A parsed TPTP formula with its name and role.
+struct AnnotatedFormula {
+    std::string name_;                  ///< Formula name (e.g., "axiom1")
+    FormulaRole role_ = FormulaRole::kPlain;  ///< Semantic role
+    std::unique_ptr<Formula> formula_;  ///< The FOL formula (for fof(...))
+    std::vector<Clause> clauses_;       ///< Direct clauses (for cnf(...))
+    bool is_cnf_ = false;               ///< true if input was cnf(), false if fof()
+};
+
+/// A complete parsed TPTP problem.
+struct ParsedProblem {
+    std::vector<AnnotatedFormula> formulas_;
+
+    /// Does any formula contain an equality predicate?
+    bool has_equality_ = false;
+
+    /// Original file path (for error messages).
+    std::string source_file_;
+};
+
+/// Parse a TPTP file.
+///
+/// For `cnf(...)` entries: clauses are built directly (no clausification needed).
+/// For `fof(...)` entries: Formula AST is built (clausification happens later).
+///
+/// All symbols are interned into `symbols` and terms into `bank` during parsing.
+ParsedProblem parseTptpFile(const std::string& filename, TermBank& bank, SymbolTable& symbols);
+
+/// Parse a TPTP string (for testing).
+ParsedProblem parseTptpString(const std::string& input, TermBank& bank, SymbolTable& symbols);
+
+/// Prepare a parsed problem for proving:
+///   1. Negate conjecture formulas.
+///   2. Clausify all fof() formulas.
+///   3. Collect all cnf() clauses directly.
+///   4. Assign ClauseIds and set provenance to kInput.
+///
+/// Returns the final clause set ready for the Prover.
+std::vector<Clause> prepareForProving(ParsedProblem& problem, TermBank& bank, SymbolTable& symbols);
+
+}  // namespace atp