from argparse import ArgumentParser
from pdb import pm
import json

from miasm2.analysis.machine import Machine
from miasm2.analysis.binary import Container
from miasm2.analysis.depgraph import DependencyGraph
from miasm2.expression.expression import ExprMem, ExprId, ExprInt

parser = ArgumentParser("Dependency grapher")
parser.add_argument("filename", help="Binary to analyse")
parser.add_argument("func_addr", help="Function address")
parser.add_argument("target_addr", help="Address to start")
parser.add_argument("element", nargs="+", help="Elements to track")
parser.add_argument("-m", "--architecture",
                    help="Architecture (%s)" % Machine.available_machine())
parser.add_argument("-i", "--implicit", help="Use implicit tracking",
                    action="store_true")
parser.add_argument("--unfollow-mem", help="Stop on memory statements",
                    action="store_true")
parser.add_argument("--unfollow-call", help="Stop on call statements",
                    action="store_true")
parser.add_argument("--do-not-simplify", help="Do not simplify expressions",
                    action="store_true")
parser.add_argument("--rename-args",
                    help="Rename common arguments (@32[ESP_init] -> Arg1)",
                    action="store_true")
parser.add_argument("--json",
                    help="Output solution in JSON",
                    action="store_true")
args = parser.parse_args()

# Get architecture
with open(args.filename, "rb") as fstream:
    cont = Container.from_stream(fstream)

arch = args.architecture if args.architecture else cont.arch
machine = Machine(arch)

# Check elements
elements = set()
regs = machine.mn.regs.all_regs_ids_byname
for element in args.element:
    try:
        elements.add(regs[element])
    except KeyError:
        raise ValueError("Unknown element '%s'" % element)

mdis = machine.dis_engine(cont.bin_stream, dont_dis_nulstart_bloc=True)
ir_arch = machine.ira(mdis.loc_db)

# Common argument forms
init_ctx = {}
if args.rename_args:
    if arch == "x86_32":
        # StdCall example
        for i in xrange(4):
            e_mem = ExprMem(ExprId("ESP_init", 32) + ExprInt(4 * (i + 1), 32), 32)
            init_ctx[e_mem] = ExprId("arg%d" % i, 32)

# Disassemble the targeted function
asmcfg = mdis.dis_multiblock(int(args.func_addr, 0))

# Generate IR
ircfg = ir_arch.new_ircfg_from_asmcfg(asmcfg)

# Get the instance
dg = DependencyGraph(
    ircfg, implicit=args.implicit,
    apply_simp=not args.do_not_simplify,
    follow_mem=not args.unfollow_mem,
    follow_call=not args.unfollow_call
)

# Build information
target_addr = int(args.target_addr, 0)
current_block = list(ircfg.getby_offset(target_addr))[0]
assignblk_index = 0
for assignblk_index, assignblk in enumerate(current_block):
    if assignblk.instr.offset == target_addr:
        break

# Enumerate solutions
json_solutions = []
for sol_nb, sol in enumerate(dg.get(current_block.loc_key, elements, assignblk_index, set())):
    fname = "sol_%d.dot" % sol_nb
    with open(fname, "w") as fdesc:
            fdesc.write(sol.graph.dot())

    results = sol.emul(ir_arch, ctx=init_ctx)
    tokens = {str(k): str(v) for k, v in results.iteritems()}
    if not args.json:
        result = ", ".join("=".join(x) for x in tokens.iteritems())
        print "Solution %d: %s -> %s" % (sol_nb,
                                         result,
                                         fname)
        if sol.has_loop:
            print '\tLoop involved'

    if args.implicit:
        sat = sol.is_satisfiable
        constraints = {}
        if sat:
            for element in sol.constraints:
                try:
                    result = '0x%x' % sol.constraints[element].as_long()
                except AttributeError:
                    result = str(sol.constraints[element])
                constraints[element] = result
        if args.json:
            tokens["satisfiability"] = sat
            tokens["constraints"] = {str(k): str(v)
                                     for k, v in constraints.iteritems()}
        else:
            print "\tSatisfiability: %s %s" % (sat, constraints)

    if args.json:
        tokens["has_loop"] = sol.has_loop
        json_solutions.append(tokens)


if args.json:
    print json.dumps(json_solutions)
