import datetime
import json
import os
import sys
from threading import Thread, Lock
import blf
import bpy
from bpy.types import Panel
from bpy.props import EnumProperty, IntProperty, FloatProperty
from ..foundation import (benchrunner,
                          buildbot,
                          config,
                          logger,
                          progress,
                          system_info,
                          util)
from ..foundation import context as benchmark_context

################################################################################
# Global state.

QUICK_SCENES = ["bmw27",
                "classroom"]

COMPLETE_SCENES = ["barbershop_interior",
                   "bmw27",
                   "classroom",
                   "fishy_cat",
                   "koro",
                   "pavillon_barcelona",
                   "victor"]

global_result_platform = None
global_progress_status = None
global_result_stats = None
global_result_dict = None
global_background_image_path = ""
global_scene_status = {}
images = {}
current_progress = 0.0
progress_lock = Lock()

################################################################################
# Draw Utilities.

font_id = 0

def viewport_size():
    import bgl
    viewport = bgl.Buffer(bgl.GL_INT, 4)
    bgl.glGetIntegerv(bgl.GL_VIEWPORT, viewport)
    return viewport[2], viewport[3]

def draw_text_center(text, x, y):
    dim = blf.dimensions(font_id, text)
    cx = x - int(dim[0]/2)
    cy = y - int(dim[1]/2)
    blf.position(font_id, cx, cy, 0)

    blf.draw(font_id, text)

def draw_text_multiline(text, x, y):
    ui_scale = bpy.context.user_preferences.system.ui_scale
    height = int(blf.dimensions(font_id, "Dummy Text")[1])
    space = int(8 * ui_scale)

    for line in text.split('\n'):
        blf.position(font_id, x, y - height, 0)
        blf.draw(font_id, line)
        y -= height + space

def draw_rect(x, y, w, h, color):
    import gpu
    gpu.draw.rect(x, y, x + w, y + h, color[0], color[1], color[2], color[3])

def draw_image(filepath, x, y, w, h):
    global images
    if filepath not in images:
        ima = bpy.data.images.load(filepath)
        images[filepath] = ima

    import gpu
    gpu.draw.image(images[filepath], x, y, x + w, y + h)


################################################################################
# Draw.

def benchmark_draw_post_pixel(arg1, arg2):
    global progress_lock
    progress_lock.acquire()
    progress_status = global_progress_status
    result_platform = global_result_platform
    result_stats = global_result_stats
    result_dict = global_result_dict
    progress_lock.release()

    ui_scale = bpy.context.user_preferences.system.ui_scale
    blf.color(font_id, 1.0, 1.0, 1.0, 1.0)

    window_width, window_height = viewport_size()

    # Image
    image_h = 370 * ui_scale
    image_y = window_height - image_h

    if global_background_image_path:
        draw_image(global_background_image_path, 0, image_y, window_width, image_h)
    else:
        splash_dir = os.path.dirname(os.path.abspath(__file__))
        splash_filepath = os.path.join(splash_dir, 'splash.png')
        draw_image(splash_filepath, 0, image_y, window_width, image_h)

    if result_dict:
        x = 0.5 * window_width
        y = 0.70 * window_height

        score = 0
        for stat in global_result_dict["stats"]:
            if stat["result"] == "OK":
                score += stat["total_render_time"]
            else:
                score = -1

        blf.size(font_id, int(32 * ui_scale), 72)
        if score >= 0:
            draw_text_center("Render time is: {}" . format(
                util.humanReadableTimeDifference(score)), x, y)
        else:
            # TODO(sergey): What is the score?
            draw_text_center("CRASH :(", x, y)

    elif result_stats or result_platform or progress_status:
        blf.size(font_id, int(12 * ui_scale), 72)

        x = 50.0 * ui_scale
        y = image_y - 20 * ui_scale

        # Stats
        if result_platform:
            draw_text_multiline(result_platform, 0.5 * window_width + x, y)
        if result_stats:
            draw_text_multiline(result_stats, x, y)

        # Progress
        progress_x = 0.0
        progress_y = image_y + 1
        progress_w = window_width * current_progress
        progress_h = 15.0 * ui_scale
        progress_color = [0.8, 1.0, 1.0, 0.2]

        draw_rect(progress_x, progress_y, progress_w, progress_h, progress_color)

        # Current status
        if global_progress_status:
            blf.size(font_id, int(18 * ui_scale), 72)
            draw_text_multiline(global_progress_status,
                                progress_x + 8.0 * ui_scale,
                                progress_y + progress_h + int(22 * ui_scale))

    else:
        # Title
        x = 0.5 * window_width
        y = 0.70 * window_height

        blf.size(font_id, int(32 * ui_scale), 72)
        draw_text_center("Blender Benchmark 1.0", x, y)

        y -= 32 * ui_scale

        blf.size(font_id, int(12 * ui_scale), 72)
        draw_text_center("Explore the results on opendata.blender.org", x, y)

    # Bottom bar
    bottom_x = 0
    bottom_y = 0
    bottom_w = window_width
    bottom_h = 52 * ui_scale
    bottom_color = [0.2, 0.2, 0.2, 1.0]

    draw_rect(bottom_x, bottom_y, bottom_w, bottom_h, bottom_color)

    # Logo
    # TODO(sergey): Make it DPI aware.
    logo_dir = os.path.dirname(os.path.abspath(__file__))
    logo_filepath = os.path.join(logo_dir, 'blender.png')
    draw_image(logo_filepath, 12, (bottom_h - 24) / 2, 85, 24)


handle_draw = bpy.types.SpaceBenchmark.draw_handler_add(
    benchmark_draw_post_pixel, (None, None), 'WINDOW', 'POST_PIXEL')

################################################################################
# Benchmark foundation integration.

class ProgressProviderSink:
    current_progress = 0.0
    current_step = ''
    current_scene = ''

    def __init__(self):
        self.current_progress = 0.0
        self.current_step = ''

    def progress(self, count, total, prefix="", suffix=""):
        progress_lock.acquire()
        if total != 0:
            self.current_progress = float(count) / float(total)
        else:
            self.current_progress = 0.0
        progress_lock.release()

    def clear(self):
        progress_lock.acquire()
        self.current_progress = 0
        progress_lock.release()

    def step(self, step_name):
        progress_lock.acquire()
        if self.current_step != step_name:
            self.current_step = step_name
            self.current_progress = 0
        progress_lock.release()
           
    def scene(self, scene_name):
        progress_lock.acquire()
        self.current_scene = scene_name
        if scene_name:
            global global_scene_status
            global_scene_status[scene_name] = "Rendering..."
        progress_lock.release()

    def scene_stats(self, scene_name, stats):
        progress_lock.acquire()
        global global_scene_status
        if stats:
            global_scene_status[scene_name] = util.humanReadableTimeDifference(
                    stats.total_render_time)
        else:
            global_scene_status[scene_name] = "Crashed :("
        progress_lock.release()


class LoggerProviderSink:
    def HEADER(self, *args):
        pass

    def WARNING(self, *args):
        pass

    def ERROR(self, *args):
        pass

    def OK(self, *args):
        pass

    def BOLD(self, *args):
        pass

    def INFO(self, *args):
        pass

    def DEBUG(self, *args):
        pass

    def FATAL(self, *args):
        pass

################################################################################
# Benchmark thread.

def string_strip_trademark(name):
    return name.replace("(R)", "").replace("(TM)", "")

def correct_device_name(name):
    if (name.startswith("TITAN") or
        name.startswith("Quadro") or
        name.startswith("GeForce")):
      return "Nvidia " + name;
    if (name.startswith("Radeon")):
        return "AMD " + name;
    return name

def construct_gpu_string(system_info):
    gpu_names = []
    for device in system_info["devices"]:
        if device["type"] == "CPU":
            continue
        gpu_names.append(correct_device_name(device["name"]))
    return ", " . join(gpu_names)

def construct_platform_string(system_info):
    """
    Construct human readable platform string to show in the interface.
    """
    result = ""
    result += "Operation System: {} {} bit" . format(system_info["system"],
                                                     system_info["bitness"])
    result += "\nCPU: {}" . format(
            string_strip_trademark(system_info["cpu_brand"]))
    gpus = construct_gpu_string(system_info)
    if gpus:
        result += "\nGPU(s): {}" . format(gpus)
    return result

def convert_result_to_json_dict(ctx, results):
    # Convert custom classes to dictionaries for easier JSON dump.
    json_results = results
    stats = json_results['stats']
    json_results['stats'] = []
    for scene in ctx.scenes:
        if scene not in stats:
            continue
        stat = stats[scene]
        if stat:
            stat = stat.asDict()
            stat['result'] = 'OK'
        else:
            stat = {'result': 'CRASH'}
        stat["scene_name"] = scene
        json_results['stats'] .append(stat)
    return json_results


def benchmark_thread(ctx):
    global progress_lock, global_result_platform, global_progress_status

    progress_lock.acquire()
    global_progress_status = "Collecting system information..."
    progress_lock.release()

    # This is all system information Blender knows.
    # NOTE: We override executable since cpuinfo uses it, and it is set
    # to blender.
    old_executable = sys.executable
    sys.executable = bpy.app.binary_path_python
    blender_system_info = system_info.gatherSystemInfo(ctx)

    # This is actual device configuration which is used to render the
    # benchmark scene.
    blender_device_info = benchrunner.benchmarkGetDeviceInfo(ctx)
    if not blender_device_info['device_type']:
        # TODO(sergey): Report an error somehow.
        return

    progress_lock.acquire()
    global_result_platform = construct_platform_string(blender_system_info)
    progress_lock.release()

    progress_lock.acquire()
    global_progress_status = "Prepating render..."
    progress_lock.release()

    all_stats = benchrunner.benchmarkAll(ctx)
    # Gather all information together.
    timestamp = datetime.datetime.now(datetime.timezone.utc).isoformat()
    result = convert_result_to_json_dict(ctx, {
        "timestamp": timestamp,
        "blender_version": system_info.getBlenderVersion(ctx),
        "system_info": blender_system_info,
        "device_info": blender_device_info,
        "stats": all_stats if all_stats else {}
    })

    global global_result_dict
    global_result_dict = result


################################################################################
# Panels

class BENCHMARK_PT_main(Panel):
    bl_label = "Benchmark"
    bl_options = {'HIDE_HEADER'}
    bl_space_type = 'BENCHMARK'
    bl_region_type = 'WINDOW'

    def draw_welcome(self, context):
        layout = self.layout

        split = layout.split(0.65)
        split.label()
        split = split.split(0.97)

        col = split.column()
        sub = col.row()
        sub.scale_y = 64.0
        sub.separator()

        sub = col.row()
        sub.scale_y = 2.25
        props = sub.operator("benchmark.run", text="QUICK BENCHMARK")
        props.run_type = 'QUICK'

        col.separator()

        sub = col.row()
        sub.emboss = 'NONE'
        sub.scale_y = 1.5
        props = sub.operator("benchmark.run", text="COMPLETE BENCHMARK (approx. 1.h)")
        props.run_type = 'COMPLETE'

        split.label()

    def draw_submit(self, context):
        layout = self.layout

        split = layout.split(0.65)
        split.label()
        split = split.split(0.97)

        col = split.column()
        sub = col.row()
        sub.scale_y = 64.0
        sub.separator()

        sub = col.row()
        sub.scale_y = 2.25
        sub.operator("benchmark.share", text="SHARE")

        sub = col.row()
        sub.emboss = 'NONE'
        sub.scale_y = 1.5
        sub.operator("benchmark.save", text="SAVE")

        split.label()

    def draw(self, context):
        screen_index = 0
        global progress_lock
        progress_lock.acquire()
        if global_result_dict:
            screen_index = 2
        elif global_result_stats or global_progress_status:
            screen_index = 1
        progress_lock.release()

        if screen_index == 0:
            self.draw_welcome(context)
        elif screen_index == 2:
            self.draw_submit(context)


################################################################################
# Operator

class BENCHMARK_OT_run(bpy.types.Operator):
    "Run Blender benchmark"
    bl_label = "Run Benchmark"
    bl_idname = "benchmark.run"

    enum_run_type = (
        ('QUICK', "QUICK", ""),
        ('COMPLETE', "COMPLETE", ""),
    )

    run_type: EnumProperty(
        name="Run Type",
        description="",
        items=enum_run_type,
        default='QUICK',
    )

    benchmark_context = None
    thread = None
    timer = None
    progress_provider = None
    logger_provider = None

    def setup_sink(self):
        self.progress_provider = ProgressProviderSink()
        self.logger_provider = LoggerProviderSink()
        progress.setProvider(self.progress_provider)
        logger.setProvider(self.logger_provider)

    def update_status(self, context):
        global global_progress_status, global_background_image_path
        progress_lock.acquire()
        step = self.progress_provider.current_step
        if step == 'WARM_UP':
            global_progress_status = "Rendering warm-up pass..."
        elif step == 'RUN':
            global current_progress
            current_progress = self.progress_provider.current_progress
            global_progress_status = "Rendering..."
        context.area.tag_redraw()
        # Path to currently displayed background image.
        current_scene = self.progress_provider.current_scene
        if current_scene:
            global_background_image_path = os.path.join(
                self.benchmark_context.scenes_dir,
                current_scene,
                current_scene + ".png")
        else:
            global_background_image_path = ""
        # Update per-scene status string
        global global_result_stats
        global_result_stats = ""
        for scene in global_scene_status:
            global_result_stats += "{}: {}\n" . format(
                    scene, global_scene_status[scene])
        progress_lock.release()

    def done(self, context):
        global global_progress_status, global_result_stats, current_progress
        wm = context.window_manager
        wm.event_timer_remove(self.timer)
        # Restore all modifications to the benchmark foundation.
        progress.restoreDefaultProvider()
        logger.restoreDefaultProvider()
        # Destroy objects of sinks.
        del self.progress_provider
        del self.logger_provider
        self.progress_provider = None
        self.logger_provider = None
        # Construct final stats string
        global global_result_dict
        global_result_stats = ""
        for stat in global_result_dict["stats"]:
            if global_result_stats:
                global_result_stats += "\n"
            if stat["result"] == "OK":
                global_result_stats += "{}: {}" . format(stat["scene_name"],
                    util.humanReadableTimeDifference(stat["total_render_time"]))
            else:
                global_result_stats += "{}: {}" . format(stat["scene_name"],
                    stat["result"])
        # TOGO(sergey): Use some more nice picture for the final slide.
        global global_background_image_path
        global_background_image_path = ""
        # Tag for nice redraw
        global_progress_status = ""
        current_progress = 0.0
        context.area.tag_redraw()

    def modal(self, context, event):
        if event.type == 'TIMER':
            if self.thread.is_alive():
                self.update_status(context)
                return {'PASS_THROUGH'}
            else:
                self.done(context)
                return {'FINISHED'}

        return {'PASS_THROUGH'}

    def invoke(self, context, event):
        global global_result_platform, global_progress_status
        global global_scene_status
        global_result_platform = ""
        global_progress_status = "Initializing..."
        context.area.tag_redraw()

        # Before doing anything, make sure we have all sinks set up, so we do
        # not miss any progress report.
        self.setup_sink()
        wm = context.window_manager
        script_directory = os.path.dirname(os.path.realpath(__file__))
        benchmark_binary_dir = os.path.dirname(bpy.app.binary_path)
        benchmark_script_directory = os.path.dirname(script_directory)
        configure_script = os.path.join(
                benchmark_script_directory, "configure.py")
        ctx = benchmark_context.Context()
        # TODO(sergey): Update for MacOS and Windows.
        ctx.blender = os.path.join(benchmark_binary_dir, "blender", "blender")
        ctx.configure_script = configure_script
        if self.run_type == 'QUICK':
            ctx.scenes = QUICK_SCENES
        else:
            ctx.scenes = COMPLETE_SCENES
        for scene in ctx.scenes:
            global_scene_status[scene] = "N/A"
        ctx.scenes_dir = os.path.join(benchmark_binary_dir, "scenes")
        ctx.device_type = 'CPU'
        # Only applies for GPU, should match Cycles name
        ctx.device_name = ""
        # Set this to True when having multiple GPUs of same name and only
        # one of the mis to be enabled. Or when requesting GPU render without
        # specifying GPU name.
        ctx.device_single = True
        # ctx.image_output_dir = "/tmp/"
        self.benchmark_context = ctx
        # Create thread for the actual benchmark.
        self.thread = Thread(target = benchmark_thread,
                             args = (self.benchmark_context, ))
        self.thread.start()
        # Create timer to query thread status
        self.timer = wm.event_timer_add(0.1, context.window)
        # Register self as modal.
        context.window_manager.modal_handler_add(self)
        return {'RUNNING_MODAL'}

    def cancel(self, context):
        # When users closes window
        return

class BENCHMARK_OT_save(bpy.types.Operator):
    bl_idname = "benchmark.save"
    bl_label = "Save Benchmark Result"

    filepath: bpy.props.StringProperty(
        subtype='FILE_PATH',
        options={'SKIP_SAVE'},
    )

    def execute(self, context):
        with open(self.filepath, "w") as f:
            f.write(json.dumps(global_result_dict, sort_keys=True, indent=2))
        return {'FINISHED'}

    def invoke(self, context, event):
        import os

        if not self.filepath:
            self.filepath = os.path.join(
                os.path.expanduser("~"), "benchmark-result.txt")

        wm = context.window_manager
        wm.fileselect_add(self)
        return {'RUNNING_MODAL'}

class BENCHMARK_OT_share(bpy.types.Operator):
    bl_idname = "benchmark.share"
    bl_label = "Share Benchmark Result"

    def invoke(self, context, event):
        return {'FINISHED'}


################################################################################
# Tweak User Preferences

userpref = bpy.context.user_preferences
theme = userpref.themes[0]
theme.user_interface.wcol_tool.inner = [0.408, 0.690, 0.129, 1.0]
theme.user_interface.wcol_tool.inner_sel = [0.308, 0.590, 0.029, 1.0]
theme.user_interface.wcol_tool.outline = [0.408, 0.690, 0.129]
theme.benchmark.space.back = [0.26, 0.26, 0.26]

style = userpref.ui_styles[0]
style.widget.points = 12

################################################################################
# Registration

classes = (
    BENCHMARK_PT_main,
    BENCHMARK_OT_run,
    BENCHMARK_OT_save,
    BENCHMARK_OT_share,
)