#!/usr/bin/env python
# SPDX-License-Identifier: CERN-OHL-S-2.0
"""

Copyright (c) 2025 FPGA Ninja, LLC

Authors:
- Alex Forencich

"""

import itertools
import logging
import os

import cocotb_test.simulator

import cocotb
from cocotb.clock import Clock
from cocotb.triggers import RisingEdge, Timer
from cocotb.regression import TestFactory

from cocotbext.axi import AxiLiteBus, AxiLiteMaster
from cocotbext.axi import AxiStreamBus, AxiStreamSource, AxiStreamFrame


class TB(object):
    def __init__(self, dut):
        self.dut = dut

        self.log = logging.getLogger("cocotb.tb")
        self.log.setLevel(logging.DEBUG)

        cocotb.start_soon(Clock(dut.clk, 10, units="ns").start())

        self.stat_source = AxiStreamSource(AxiStreamBus.from_entity(dut.s_axis_stat), dut.clk, dut.rst)

        self.axil_master = AxiLiteMaster(AxiLiteBus.from_entity(dut.s_axil), dut.clk, dut.rst)

    def set_idle_generator(self, generator=None):
        if generator:
            self.stat_source.set_pause_generator(generator())
            self.axil_master.write_if.aw_channel.set_pause_generator(generator())
            self.axil_master.write_if.w_channel.set_pause_generator(generator())
            self.axil_master.read_if.ar_channel.set_pause_generator(generator())

    def set_backpressure_generator(self, generator=None):
        if generator:
            self.axil_master.write_if.b_channel.set_pause_generator(generator())
            self.axil_master.read_if.r_channel.set_pause_generator(generator())

    async def cycle_reset(self):
        self.dut.rst.setimmediatevalue(0)
        await RisingEdge(self.dut.clk)
        await RisingEdge(self.dut.clk)
        self.dut.rst.value = 1
        await RisingEdge(self.dut.clk)
        await RisingEdge(self.dut.clk)
        self.dut.rst.value = 0
        await RisingEdge(self.dut.clk)
        await RisingEdge(self.dut.clk)


async def run_test_strings(dut, idle_inserter=None, backpressure_inserter=None):

    tb = TB(dut)

    await tb.cycle_reset()

    tb.set_idle_generator(idle_inserter)
    tb.set_backpressure_generator(backpressure_inserter)

    await Timer(4000, 'ns')

    for n in range(10):
        s1 = f'BLK'
        s2 = f'STR_{n}'
        s = f'{s1:8}{s2:8}'

        print(s)

        b = s.encode('ascii')
        for k in range(0, 8):
            val = k
            for m in range(2):
                c = b[k*2+m]
                c = (c & 0x1f) | (0x20 if c & 0x40 else 0)
                val |= c << (4+6*m)

            await tb.stat_source.send(AxiStreamFrame([val], tid=n, tuser=1))
            await tb.stat_source.send(AxiStreamFrame([0xdead], tid=n, tuser=0))

    await Timer(12000, 'ns')

    data = await tb.axil_master.read_words(0, 10, ws=16)

    print(data)

    for i, d in enumerate(data):
        s = d.to_bytes(16, 'little')
        print(s)

        s = (s[0:8].strip() + b"." + s[8:].strip()).decode('ascii')
        print(s)

        assert s == f'BLK.STR_{i}'

    await RisingEdge(dut.clk)
    await RisingEdge(dut.clk)


def cycle_pause():
    return itertools.cycle([1, 1, 1, 0])


if getattr(cocotb, 'top', None) is not None:

    for test in [run_test_strings]:

        factory = TestFactory(test)
        factory.add_option("idle_inserter", [None, cycle_pause])
        factory.add_option("backpressure_inserter", [None, cycle_pause])
        factory.generate_tests()


# cocotb-test

tests_dir = os.path.dirname(__file__)
rtl_dir = os.path.abspath(os.path.join(tests_dir, '..', '..', 'rtl'))
lib_dir = os.path.abspath(os.path.join(tests_dir, '..', '..', 'lib'))
taxi_src_dir = os.path.abspath(os.path.join(lib_dir, 'taxi', 'src'))


def process_f_files(files):
    lst = {}
    for f in files:
        if f[-2:].lower() == '.f':
            with open(f, 'r') as fp:
                l = fp.read().split()
            for f in process_f_files([os.path.join(os.path.dirname(f), x) for x in l]):
                lst[os.path.basename(f)] = f
        else:
            lst[os.path.basename(f)] = f
    return list(lst.values())


def test_taxi_stats_strings_full(request):
    dut = "taxi_stats_strings_full"
    module = os.path.splitext(os.path.basename(__file__))[0]
    toplevel = module

    verilog_sources = [
        os.path.join(tests_dir, f"{toplevel}.sv"),
        os.path.join(rtl_dir, f"{dut}.sv"),
        os.path.join(taxi_src_dir, "axis", "rtl", "taxi_axis_if.sv"),
        os.path.join(taxi_src_dir, "axi", "rtl", "taxi_axil_if.sv"),
    ]

    verilog_sources = process_f_files(verilog_sources)

    parameters = {}

    parameters['PIPELINE'] = 2
    parameters['STAT_INC_W'] = 16
    parameters['STAT_ID_W'] = 8
    parameters['AXIL_DATA_W'] = 32
    parameters['AXIL_ADDR_W'] = parameters['STAT_ID_W'] + 4

    extra_env = {f'PARAM_{k}': str(v) for k, v in parameters.items()}

    sim_build = os.path.join(tests_dir, "sim_build",
        request.node.name.replace('[', '-').replace(']', ''))

    cocotb_test.simulator.run(
        simulator="verilator",
        python_search=[tests_dir],
        verilog_sources=verilog_sources,
        toplevel=toplevel,
        module=module,
        parameters=parameters,
        sim_build=sim_build,
        extra_env=extra_env,
    )
