#!/usr/bin/env python3
"""Generate ts_generated.h with all indicator declarations and test registry.

Parses lib/*.c for ts_parameter_t declarations and emits:
- extern ts_parameter_t const ts_<name>_p
- uint_t ts_<name>_offset(...)
- int ts_<name>(...)
- bool ts_test_<name>(void)   [inside #ifdef TS_IMPLEMENTATION]
"""

import importlib.util
import os
import re
import sys

_spec = importlib.util.spec_from_file_location(
    "ts_parser",
    os.path.join(os.path.dirname(os.path.abspath(__file__)), "ts_parser.py"),
)
if _spec and _spec.loader:
    _ts_parser = importlib.util.module_from_spec(_spec)
    _spec.loader.exec_module(_ts_parser)
    parse_all = _ts_parser.parse_all
else:
    print("Error: could not load ts_parser", file=sys.stderr)
    sys.exit(1)

ROOT = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
TEST_DIR = os.path.join(ROOT, "test")
OUT_H = os.path.join(ROOT, "ts_generated.h")
OUT_TEST = os.path.join(TEST_DIR, "main_generated.c")


def generate_header(funcs):
    """Generate ts_generated.h."""
    lines = []
    lines.append("/* Auto-generated indicator declarations. Do not edit. */")
    lines.append("")
    lines.append("#ifndef TS_GENERATED_H")
    lines.append("#define TS_GENERATED_H")
    lines.append("")

    for fm in funcs:
        lines.append("extern ts_parameter_t const ts_" + fm.name + "_p;")
        lines.append("uint_t ts_" + fm.name + "_offset( ts_constant_t const * );")
        lines.append(
            "int ts_"
            + fm.name
            + "( fp_t * const *y, uint_t y_n, fp_t const * const *x, "
            "uint_t x_n, uint_t n, ts_constant_t const *c );"
        )

    lines.append("")
    lines.append("#ifdef TS_IMPLEMENTATION")
    lines.append("")
    for fm in funcs:
        lines.append("bool ts_test_" + fm.name + "( void );")
    lines.append("")
    lines.append("#endif /* TS_IMPLEMENTATION */")
    lines.append("")
    lines.append("#endif /* TS_GENERATED_H */")
    lines.append("")

    return "\n".join(lines)


def generate_test_main(funcs):
    """Generate test/main_generated.c with extern declarations and test array."""
    lines = []
    lines.append("/* Auto-generated test registry. Do not edit. */")
    lines.append("")
    lines.append("#define EXTERN_TEST(name) extern bool ts_test_##name(void)")
    for fm in funcs:
        lines.append("EXTERN_TEST(" + fm.name + ");")
    lines.append("#undef EXTERN_TEST")
    lines.append("")
    lines.append("typedef struct {")
    lines.append("    const char *name;")
    lines.append("    bool (*func)(void);")
    lines.append("} test_case_t;")
    lines.append("")
    lines.append("#define TEST_ENTRY(name) { #name, ts_test_##name }")
    lines.append("")
    lines.append("static test_case_t tests[] = {")
    for fm in funcs:
        lines.append("    TEST_ENTRY(" + fm.name + "),")
    lines.append("};")
    lines.append("")
    lines.append("#define NUM_TESTS (sizeof(tests) / sizeof(tests[0]))")
    lines.append("")
    lines.append("#undef TEST_ENTRY")
    lines.append("")

    return "\n".join(lines)


def _is_valid_c_identifier(name):
    return bool(re.match(r"^[a-zA-Z_][a-zA-Z0-9_]*$", name))


def main():
    funcs = parse_all(detect_x_access=False)

    if not funcs:
        print("Warning: no ts_parameter declarations found.", file=sys.stderr)
        return 1

    for fm in funcs:
        if not _is_valid_c_identifier(fm.name):
            print(f"Error: invalid C identifier '{fm.name}'", file=sys.stderr)
            return 1

    os.makedirs(TEST_DIR, exist_ok=True)

    try:
        with open(OUT_H, "w", encoding="utf-8") as f:
            f.write(generate_header(funcs))
    except OSError as e:
        print(f"Error writing {OUT_H}: {e}", file=sys.stderr)
        return 1

    try:
        with open(OUT_TEST, "w", encoding="utf-8") as f:
            f.write(generate_test_main(funcs))
    except OSError as e:
        print(f"Error writing {OUT_TEST}: {e}", file=sys.stderr)
        return 1

    print(f"Generated {len(funcs)} declarations -> {OUT_H}")
    print(f"Generated test registry -> {OUT_TEST}")
    return 0


if __name__ == "__main__":
    sys.exit(main())