#include "vxBoot/loader.h"
#include "vxBoot/terminal.h"
#include "vxBoot/fs/smemfs.h"

#include <stdio.h>
#include <string.h>

/* section_get_id() : generate id string */
static char *section_get_id(int id)
{
	static char buff[6];

	snprintf(buff, 6, "[%2d]", id);
	return (buff);
}

/* section_get_name() : get the section name*/
static char *section_get_name(void const *inode, int nameoff, off_t shstroff)
{
	static char buff[10];

	smemfs_pread(inode, buff, 9, nameoff + shstroff);
	if (strlen(buff) >= 8) {
		buff[8] = '\0';
		buff[7] = '.';
	}
	return (buff);
}

/* section_get_type() : return the section type*/
static char const *section_get_type(int type)
{
	static struct {
		int type;
		char const * const name;
	} const types[] = {
		{.type = SHT_NULL,          .name = "NULL"},
		{.type = SHT_PROGBITS,      .name = "PROGBITS"},
		{.type = SHT_SYMTAB,        .name = "SYMTAB"},
		{.type = SHT_STRTAB,        .name = "STRTAB"},
		{.type = SHT_RELA,          .name = "RELA"},
		{.type = SHT_HASH,          .name = "HASH"},
		{.type = SHT_DYNAMIC,       .name = "DYNAMIC"},
		{.type = SHT_NOTE,          .name = "NOTE"},
		{.type = SHT_NOBITS,        .name = "NOBITS"},
		{.type = SHT_REL,           .name = "REL"},
		{.type = SHT_SHLIB,         .name = "SHLIB"},
		{.type = SHT_DYNSYM,        .name = "DYNSYM"},
		{.type = SHT_INIT_ARRAY,    .name = "INIT_ARRAY"},
		{.type = SHT_FINI_ARRAY,    .name = "FINI_ARRAY"},
		{.type = SHT_PREINIT_ARRAY, .name = "PREINIT_ARRAY"},
		{.type = SHT_GROUP,         .name = "GROUP"},
		{.type = SHT_SYMTAB_SHNDX,  .name = "SYMTAB SECTION INDICES"},
		{.type = -1, .name = NULL},
	};
	for (int i = 0; types[i].name != NULL; ++i) {
		if (types[i].type == type)
			return (types[i].name);
	}
	return ("UNKNOWN");
}



/* loader_info() : display ELF PIE file information */
//TODO: secure
int loader_info(struct smemfs_inode const * inode, Elf32_Ehdr *hdr)
{
	Elf32_Shdr shdr;
	off_t stroff;
	off_t shoff;

	/* find the section header table */
	shoff = hdr->e_shoff;

	/* find the section string table ".strtable" */
	smemfs_pread(
		inode,
		&shdr, sizeof(Elf32_Shdr),
		shoff + (sizeof(Elf32_Shdr) * hdr->e_shstrndx)
	);
	stroff = shdr.sh_offset;

	/* display section information */
	terminal_write(
		"There are %d section headers, startting at offset %#x\n",
		hdr->e_shnum, hdr->e_shoff
	);
	terminal_write("Section Headers:\n");
	terminal_write(
		"%4s %-8s %-8s %-8s %-8s\n",
		"[Nr]", "Name", "Type", "Address", "Offset"
	);
	for (int i = 0; i < hdr->e_shnum; ++i) {
		smemfs_pread(inode, &shdr, sizeof(Elf32_Shdr), shoff);
		terminal_write(
			"%4s %-8s %-8s %08x %08x\n",
			section_get_id(i),
			section_get_name(inode, shdr.sh_name, stroff),
			section_get_type(shdr.sh_type),
			shdr.sh_addr,
			shdr.sh_offset
		);
		shoff += sizeof(Elf32_Shdr);
	}
	return (0);
}