# This file is Copyright (c) 2013 Florent Kermarrec <florent@enjoy-digital.fr>
# License: BSD

import os
import subprocess

from migen.fhdl.structure import _Fragment
from mibuild.generic_platform import *

from mibuild import tools
from mibuild.xilinx import common


def _format_constraint(c):
    if isinstance(c, Pins):
        return "set_location_assignment PIN_" + c.identifiers[0]
    elif isinstance(c, IOStandard):
        return "set_instance_assignment -name IO_STANDARD " + "\"" + c.name + "\""
    elif isinstance(c, Misc):
        return c.misc


def _format_qsf(signame, pin, others, resname):
    fmt_c = [_format_constraint(c) for c in ([Pins(pin)] + others)]
    fmt_r = resname[0] + ":" + str(resname[1])
    if resname[2] is not None:
        fmt_r += "." + resname[2]
    r = ""
    for c in fmt_c:
        r += c + " -to " + signame + " # " + fmt_r + "\n"
    return r


def _build_qsf(named_sc, named_pc):
    r = ""
    for sig, pins, others, resname in named_sc:
        if len(pins) > 1:
            for i, p in enumerate(pins):
                r += _format_qsf(sig + "[" + str(i) + "]", p, others, resname)
        else:
            r += _format_qsf(sig, pins[0], others, resname)
    if named_pc:
        r += "\n" + "\n\n".join(named_pc)
    r += "set_global_assignment -name top_level_entity top\n"
    return r


def _build_files(device, sources, vincpaths, named_sc, named_pc, build_name):
    qsf_contents = ""
    for filename, language, library in sources:
        # Enforce use of SystemVerilog (Quartus does not support global parameters in Verilog)
        if language == "verilog":
            language = "systemverilog"
        qsf_contents += "set_global_assignment -name " + language.upper() + "_FILE " + filename + " -library " + library + " \n"

    for path in vincpaths:
        qsf_contents += "set_global_assignment -name SEARCH_PATH " + path + "\n"

    qsf_contents += _build_qsf(named_sc, named_pc)
    qsf_contents += "set_global_assignment -name DEVICE " + device
    tools.write_to_file(build_name + ".qsf", qsf_contents)


def _run_quartus(build_name, quartus_path):
    build_script_contents = """# Autogenerated by mibuild

quartus_map --read_settings_files=on --write_settings_files=off {build_name} -c {build_name}
quartus_fit --read_settings_files=off --write_settings_files=off {build_name} -c {build_name}
quartus_asm --read_settings_files=off --write_settings_files=off {build_name} -c {build_name}
quartus_sta {build_name} -c {build_name}

""".format(build_name=build_name)
    build_script_file = "build_" + build_name + ".sh"
    tools.write_to_file(build_script_file, build_script_contents, force_unix=True)

    r = subprocess.call(["bash", build_script_file])
    if r != 0:
        raise OSError("Subprocess failed")


class AlteraQuartusToolchain:
    def build(self, platform, fragment, build_dir="build", build_name="top",
            quartus_path="/opt/Altera", run=True):
        tools.mkdir_noerror(build_dir)
        os.chdir(build_dir)

        if not isinstance(fragment, _Fragment):
            fragment = fragment.get_fragment()
        platform.finalize(fragment)

        v_output = platform.get_verilog(fragment)
        named_sc, named_pc = platform.resolve_signals(v_output.ns)
        v_file = build_name + ".v"
        v_output.write(v_file)
        sources = platform.sources | {(v_file, "verilog", "work")}
        _build_files(platform.device, sources, platform.verilog_include_paths, named_sc, named_pc, build_name)
        if run:
            _run_quartus(build_name, quartus_path)

        os.chdir("..")

        return v_output.ns

    def add_period_constraint(self, platform, clk, period):
        # TODO: handle differential clk
        platform.add_platform_command("""set_global_assignment -name DUTY_CYCLE 50 -section_id {clk}""", clk=clk)
        platform.add_platform_command("""set_global_assignment -name FMAX_REQUIREMENT "{freq} MHz" -section_id {clk}\n""".format(freq=str(float(1/period)*1000), clk="{clk}"), clk=clk)