/*
 * SymClaw C FFI — public API header.
 *
 * Link against libsymclaw_ffi.so (dynamic) or libsymclaw_ffi.a (static).
 */

#ifndef SYMCLAW_H
#define SYMCLAW_H

#include <stdint.h>

#ifdef __cplusplus
extern "C" {
#endif

/* Opaque expression handle. */
typedef struct SymclawExpr symclaw_expr_t;

/* ── Lifecycle ──────────────────────────────────────────────── */

/* Parse a math expression string. Returns NULL on failure. */
symclaw_expr_t* symclaw_parse(const char* input);

/* Free an expression handle. Safe to call with NULL. */
void symclaw_free_expr(symclaw_expr_t* expr);

/* Free a string returned by SymClaw. Safe to call with NULL. */
void symclaw_free_string(char* s);

/* ── Conversion ─────────────────────────────────────────────── */

/* Convert expression to ASCII string. Caller frees with symclaw_free_string. */
char* symclaw_to_string(const symclaw_expr_t* expr);

/* Convert expression to LaTeX. Caller frees with symclaw_free_string. */
char* symclaw_to_latex(const symclaw_expr_t* expr);

/* ── Operations ─────────────────────────────────────────────── */

symclaw_expr_t* symclaw_simplify(const symclaw_expr_t* expr);
symclaw_expr_t* symclaw_differentiate(const symclaw_expr_t* expr, const char* var);
symclaw_expr_t* symclaw_integrate(const symclaw_expr_t* expr, const char* var);
double symclaw_eval(const symclaw_expr_t* expr, const char* var, double value);
symclaw_expr_t* symclaw_expand(const symclaw_expr_t* expr);

/* Solve expr=0 for var. Returns JSON array string. Caller frees. */
char* symclaw_solve(const symclaw_expr_t* expr, const char* var);

symclaw_expr_t* symclaw_series(const symclaw_expr_t* expr, const char* var,
                               double point, uint32_t order);
symclaw_expr_t* symclaw_limit(const symclaw_expr_t* expr, const char* var,
                              double point);

/* ── Arithmetic ─────────────────────────────────────────────── */

symclaw_expr_t* symclaw_add(const symclaw_expr_t* a, const symclaw_expr_t* b);
symclaw_expr_t* symclaw_mul(const symclaw_expr_t* a, const symclaw_expr_t* b);
symclaw_expr_t* symclaw_pow(const symclaw_expr_t* base, const symclaw_expr_t* exp);

/* ── Code Generation ────────────────────────────────────────── */

/* Generate code in target language ("python", "c", "rust", etc). Caller frees. */
char* symclaw_to_code(const symclaw_expr_t* expr, const char* language);

#ifdef __cplusplus
}
#endif

#endif /* SYMCLAW_H */