/*-
 * Copyright (c) 2015--2018 Taylor R. Campbell
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <errno.h>
#include <inttypes.h>
#include <pb.h>
#include <stdio.h>

#include "pb_dump.h"

#define	PB_ABI_VERSION	0x00000000

static int	pb_dump_by_hdr(FILE *, unsigned, const struct pb_msg_hdr *);
static int	pb_dump_field(FILE *, unsigned, const struct pb_field *,
		    const unsigned char *);
static int	pb_dump_field_value(FILE *, unsigned, const struct pb_field *,
		    const unsigned char *);

int
pb_dump(FILE *out, struct pb_msg msg)
{
	const struct pb_msg_hdr *const msg_hdr =
	    (const struct pb_msg_hdr *)msg.pbm_ptr;

	if (msg_hdr->pbmh_msgdesc != msg.pbm_msgdesc)
		/* XXX pb_bug */
		return EINVAL;
	if (!pb_abi_compatible(msg.pbm_msgdesc->pbmd_abi_version,
		PB_ABI_VERSION))
		/* XXX pb_bug */
		return EINVAL;

	return pb_dump_by_hdr(out, 0, msg_hdr);
}

static int
pb_dump_by_hdr(FILE *out, unsigned indent, const struct pb_msg_hdr *msg_hdr)
{
	const unsigned char *const addr = (const void *)msg_hdr;
	const struct pb_msgdesc *const msgdesc = msg_hdr->pbmh_msgdesc;
	size_t i;
	int error;

	for (i = 0; i < msgdesc->pbmd_nfields; i++) {
		error = pb_dump_field(out, indent, &msgdesc->pbmd_fields[i],
		    addr);
		if (error)
			return error;
	}

	return 0;
}

static int
pb_dump_field(FILE *out, unsigned indent, const struct pb_field *field,
    const unsigned char *addr)
{
	int error;

	switch (field->pbf_quant) {
	case PBQ_REQUIRED:
		return pb_dump_field_value(out, indent, field,
		    (addr + field->pbf_qu.required.offset));
	case PBQ_OPTIONAL:
		if (*(const bool *)(addr +
			field->pbf_qu.optional.present_offset))
			return pb_dump_field_value(out, indent, field,
			    (addr + field->pbf_qu.optional.value_offset));
		return 0;
	case PBQ_REPEATED: {
		const struct pb_repeated *const repeated =
		    (const struct pb_repeated *)(addr +
			field->pbf_qu.repeated.hdr_offset);
		const unsigned char *const ptr =
		    /* XXX Sketchy pointer cast.  */
		    *(const void *const *)(addr +
			field->pbf_qu.repeated.ptr_offset);
		const size_t elemsize = pb_type_size(&field->pbf_type);
		size_t i;

		/* XXX Handle packed repeated fields.  */
		for (i = 0; i < pb_repeated_count(repeated); i++) {
			error = pb_dump_field_value(out, indent, field,
			    (ptr + (i * elemsize)));
			if (error)
				return error;
		}

		return 0;
	}
	default:
		pb_bug("field %s: invalid quantifier: %d", field->pbf_name,
		    (int)field->pbf_quant);
	}
}

static int
pb_dump_field_value(FILE *out, unsigned indent, const struct pb_field *field,
    const unsigned char *v)
{
	int error;

	if (fprintf(out, "%*s%s", indent, "", field->pbf_name) < 0)
		return errno;

	switch (field->pbf_type.pbt_type) {
	case PB_TYPE_BOOL:
		if (fprintf(out, ": %s\n", *(const bool *)v? "true" : "false")
		    < 0)
			return errno;
		return 0;
	case PB_TYPE_UINT32:
	case PB_TYPE_FIXED32:
		if (fprintf(out, ": %"PRIu32"\n", *(const uint32_t *)v) < 0)
			return errno;
		return 0;
	case PB_TYPE_UINT64:
	case PB_TYPE_FIXED64:
		if (fprintf(out, ": %"PRIu64"\n", *(const uint64_t *)v) < 0)
			return errno;
		return 0;
	case PB_TYPE_INT32:
	case PB_TYPE_SINT32:
	case PB_TYPE_SFIXED32:
		if (fprintf(out, ": %"PRId32"\n", *(const int32_t *)v) < 0)
			return errno;
		return 0;
	case PB_TYPE_INT64:
	case PB_TYPE_SINT64:
	case PB_TYPE_SFIXED64:
		if (fprintf(out, ": %"PRId64"\n", *(const int64_t *)v) < 0)
			return errno;
		return 0;
	case PB_TYPE_ENUM: {
		int32_t number = *(const int32_t *)v;
		const struct pb_enumeration *const enumeration =
		    field->pbf_type.pbt_u.enumerated.enumeration;
		const struct pb_enumerand *const enumerands =
		    enumeration->pben_enumerands;
		size_t i, start = 0, end = enumeration->pben_nenumerands;

		while (start < end) {
			i = (start + ((end - start) / 2));

			if (number < enumerands[i].pbed_number)
				end = i;
			else if (number > enumerands[i].pbed_number)
				start = (i + 1);
			else
				break;
		}
		if (start < end) {
			if (fprintf(out, ": %s\n", enumerands[i].pbed_name)
			    < 0)
				return errno;
		} else {
			if (fprintf(out, ": %"PRId32"\n", number) < 0)
				return errno;
		}

		return 0;
	}
	case PB_TYPE_FLOAT:
		if (fprintf(out, ": %a\n", (double)*(const float *)v) < 0)
			return errno;
		return 0;
	case PB_TYPE_DOUBLE:
		if (fprintf(out, ": %a\n", *(const float *)v) < 0)
			return errno;
		return 0;
	case PB_TYPE_BYTES: {
		const struct pb_bytes *const bytes =
		    (const struct pb_bytes *)v;
		const uint8_t *p;
		size_t i, n;

		if (fprintf(out, ": 0x'") < 0)
			return errno;
		p = pb_bytes_ptr(bytes, &n);
		for (i = 0; i < n; i++) {
			if (fprintf(out, "%02hhx", p[i]) < 0)
				return errno;
		}
		if (fprintf(out, "'\n") < 0)
			return errno;
		return 0;
	}
	case PB_TYPE_STRING: {
		const struct pb_string *const string =
		    (const struct pb_string *)v;
		const char *const p = pb_string_ptr(string);
		const size_t len = pb_string_len(string);
		size_t i;

		if (fprintf(out, ": \"") < 0)
			return errno;
		for (i = 0; i < len; i++) {
			const uint8_t c = (uint8_t)p[i];
			char esc = '\0';

			switch (c) {
			case '\n': esc = 'n'; break;
			case '\r': esc = 'r'; break;
			case '\t': esc = 't'; break;
			case '\"': esc = '"'; break;
			case '\'': esc = '\''; break;
			case '\\': esc = '\\'; break;
			default: break;
			}

			if (esc != '\0') {
				if (fprintf(out, "\\%c", esc) < 0)
					return errno;
			} else if (c < 32 || 127 < c) {
				if (fprintf(out, "\\%03o", c) < 0)
					return errno;
			} else {
				if (fprintf(out, "%c", c) < 0)
					return errno;
			}
		}
		if (fprintf(out, "\"\n") < 0)
			return errno;
		return 0;
	}
	case PB_TYPE_MSG: {
		const struct pb_msg_hdr *const msg_hdr =
		    (const struct pb_msg_hdr *)v;

		if (fprintf(out, " {\n") < 0)
			return errno;
		error = pb_dump_by_hdr(out, indent + 2, msg_hdr);
		if (error)
			return error;
		if (fprintf(out, "%*s}\n", indent, "") < 0)
			return errno;
		return 0;
	}
	default:
		pb_bug("field %s: invalid type: %d", field->pbf_name,
		    field->pbf_type.pbt_type);
	}
}