import os
import re
import subprocess
import sys
import tempfile

from fabric.utils import idle_add, remove_handler
from fabric.utils.helpers import get_relative_path
from fabric.widgets.box import Box
from fabric.widgets.button import Button
from fabric.widgets.entry import Entry
from fabric.widgets.image import Image
from fabric.widgets.label import Label
from fabric.widgets.scrolledwindow import ScrolledWindow
from gi.repository import Gdk, GdkPixbuf, GLib

import modules.icons as icons


class ClipHistory(Box):
    def __init__(self, **kwargs):
        super().__init__(
            name="clip-history",
            visible=False,
            all_visible=False,
            **kwargs,
        )

        self.tmp_dir = tempfile.mkdtemp(prefix="cliphist-")
        self.image_cache = {}
        
        self.notch = kwargs["notch"]
        self.selected_index = -1
        self._arranger_handler = 0
        self.clipboard_items = []
        self._loading = False
        self._pending_updates = False

        self.viewport = Box(name="viewport", spacing=4, orientation="v")
        self.search_entry = Entry(
            name="search-entry",
            placeholder="Search Clipboard History...",
            h_expand=True,
            h_align="fill",
            notify_text=self.filter_items,
            on_activate=lambda entry, *_: self.use_selected_item(),
            on_key_press_event=self.on_search_entry_key_press,
        )
        self.search_entry.props.xalign = 0.5
        
        self.scrolled_window = ScrolledWindow(
            name="scrolled-window",
            spacing=10,
            h_expand=True,
            v_expand=True,
            h_align="fill",
            v_align="fill",
            child=self.viewport,
            propagate_width=False,
            propagate_height=False,
        )

        self.header_box = Box(
            name="header_box",
            spacing=10,
            orientation="h",
            children=[
                Button(
                    name="clear-button",
                    child=Label(name="clear-label", markup=icons.trash),
                    on_clicked=lambda *_: self.clear_history(),
                ),
                self.search_entry,
                Button(
                    name="close-button",
                    child=Label(name="close-label", markup=icons.cancel),
                    tooltip_text="Exit",
                    on_clicked=lambda *_: self.close()
                ),
            ],
        )

        self.history_box = Box(
            name="launcher-box",
            spacing=10,
            h_expand=True,
            orientation="v",
            children=[
                self.header_box,
                self.scrolled_window,
            ],
        )

        self.add(self.history_box)
        self.show_all()

    def close(self):
        """Close the clipboard history panel"""
        self.viewport.children = []
        self.selected_index = -1
        self.notch.close_notch()

    def open(self):
        """Open the clipboard history panel and load items"""
        if self._loading:
            return
        self._loading = True
        self.search_entry.set_text("")
        self.search_entry.grab_focus()

        # Use GLib.Thread for proper async execution
        GLib.Thread.new("cliphist-loader", self._load_clipboard_items_thread, None)

    def _load_clipboard_items_thread(self, user_data):
        """Background thread worker for loading clipboard items"""
        try:
            result = subprocess.run(
                ["cliphist", "list"], 
                capture_output=True, 
                check=True
            )
            # Decode stdout with error handling
            stdout_str = result.stdout.decode('utf-8', errors='replace')
            lines = stdout_str.strip().split('\n')
            new_items = []
            for line in lines:
                if not line or "<meta http-equiv" in line:
                    continue
                new_items.append(line)
            # Update UI from main thread
            GLib.idle_add(self._update_items, new_items)
        except subprocess.CalledProcessError as e:
            print(f"Error loading clipboard history: {e}", file=sys.stderr)
        except Exception as e:
            print(f"Unexpected error: {e}", file=sys.stderr)
        finally:
            GLib.idle_add(self._loading_finished)
    
    def _loading_finished(self):
        """Handle loading completion on main thread"""
        self._loading = False
        if self._pending_updates:
            self._pending_updates = False
            GLib.Thread.new("cliphist-loader", self._load_clipboard_items_thread, None)
        return False

    def _update_items(self, new_items):
        """Update the items list from main thread"""
        self.clipboard_items = new_items
        self.display_clipboard_items()

    def display_clipboard_items(self, filter_text=""):
        """Display clipboard items in the viewport"""
        remove_handler(self._arranger_handler) if self._arranger_handler else None
        self.viewport.children = []
        self.selected_index = -1
        

        filtered_items = []
        for item in self.clipboard_items:

            content = item.split('\t', 1)[1] if '\t' in item else item
            if filter_text.lower() in content.lower():
                filtered_items.append(item)
        

        if not filtered_items:

            container = Box(
                name="no-clip-container",
                orientation="v",
                h_align="center",
                v_align="center",
                h_expand=True,
                v_expand=True
            )
            

            label = Label(
                name="no-clip",
                markup=icons.clipboard,
                h_align="center",
                v_align="center",
            )
            
            container.add(label)
            self.viewport.add(container)
            return
            

        self._display_items_batch(filtered_items, 0, 10)

    def _display_items_batch(self, items, start, batch_size):
        """Display items in batches to keep UI responsive"""
        end = min(start + batch_size, len(items))
        
        for i in range(start, end):
            item = items[i]
            self.viewport.add(self.create_clipboard_item(item))
        

        if end < len(items):
            GLib.idle_add(self._display_items_batch, items, end, batch_size)
        else:

            if self.search_entry.get_text() and self.viewport.get_children():
                self.update_selection(0)

    def create_clipboard_item(self, item):
        """Create a button for a clipboard item"""

        parts = item.split('\t', 1)
        item_id = parts[0] if len(parts) > 1 else "0"
        content = parts[1] if len(parts) > 1 else item
        

        display_text = content.strip()
        if len(display_text) > 100:
            display_text = display_text[:97] + "..."
        

        is_image = self.is_image_data(content)
        
        if is_image:

            button = Button(
                name="slot-button",
                child=Box(
                    name="slot-box",
                    orientation="h",
                    spacing=10,
                    children=[
                        Image(name="clip-icon", h_align="start"),
                        Label(
                            name="clip-label",
                            label="[Image]",
                            ellipsization="end",
                            v_align="center",
                            h_align="start",
                            h_expand=True,
                        ),
                    ],
                ),
                tooltip_text="Image in clipboard",
                on_clicked=lambda *_, id=item_id: self.paste_item(id),
            )

            self._load_image_preview_async(item_id, button)
        else:

            button = self.create_text_item_button(item_id, display_text)
        

        button.connect("key-press-event", lambda widget, event, id=item_id: self.on_item_key_press(widget, event, id))
        

        button.set_can_focus(True)
        button.add_events(Gdk.EventMask.KEY_PRESS_MASK)
            
        return button

    def _load_image_preview_async(self, item_id, button):
        """Load image preview asynchronously using background thread"""
        GLib.Thread.new("image-preview", self._load_image_preview_thread, (item_id, button))

    def _load_image_preview_thread(self, data):
        """Background thread worker for loading image preview"""
        item_id, button = data
        try:
            if item_id in self.image_cache:
                pixbuf = self.image_cache[item_id]
                GLib.idle_add(self._update_image_button, button, pixbuf)
                return
            
            result = subprocess.run(
                ["cliphist", "decode", item_id],
                capture_output=True,
                check=True
            )
            loader = GdkPixbuf.PixbufLoader()
            loader.write(result.stdout)
            loader.close()
            pixbuf = loader.get_pixbuf()
            width, height = pixbuf.get_width(), pixbuf.get_height()
            max_size = 72
            if width > height:
                new_width = max_size
                new_height = int(height * (max_size / width))
            else:
                new_height = max_size
                new_width = int(width * (max_size / height))
            pixbuf = pixbuf.scale_simple(new_width, new_height, GdkPixbuf.InterpType.BILINEAR)
            self.image_cache[item_id] = pixbuf
            
            GLib.idle_add(self._update_image_button, button, pixbuf)
        except Exception as e:
            print(f"Error loading image preview: {e}", file=sys.stderr)

    def _update_image_button(self, button, pixbuf):
        """Update the button with the loaded image preview"""
        box = button.get_child()
        if box and len(box.get_children()) > 0:
            image_widget = box.get_children()[0]
            if isinstance(image_widget, Image):
                image_widget.set_from_pixbuf(pixbuf)

    def create_text_item_button(self, item_id, display_text):
        """Create a button for a text clipboard item"""
        return Button(
            name="slot-button",
            child=Box(
                name="slot-box",
                orientation="h",
                spacing=10,
                children=[
                    Label(
                        name="clip-icon",
                        markup=icons.clip_text,
                        h_align="start",
                    ),
                    Label(
                        name="clip-label",
                        label=display_text,
                        ellipsization="end",
                        v_align="center",
                        h_align="start",
                        h_expand=True,
                    ),
                ],
            ),
            tooltip_text=display_text,
            on_clicked=lambda *_: self.paste_item(item_id),
        )

    def is_image_data(self, content):
        """Determine if clipboard content is likely an image"""

        return (
            content.startswith("data:image/") or
            content.startswith("\x89PNG") or
            content.startswith("GIF8") or
            content.startswith("\xff\xd8\xff") or
            re.match(r'^\s*<img\s+', content) is not None or
            "binary" in content.lower() and any(ext in content.lower() for ext in ["jpg", "jpeg", "png", "bmp", "gif"])
        )

    def paste_item(self, item_id):
        """Copy the selected item to the clipboard and close (async)"""
        GLib.Thread.new("paste-item", self._paste_item_thread, item_id)

    def _paste_item_thread(self, item_id):
        """Background thread worker for pasting clipboard item"""
        try:
            result = subprocess.run(
                ["cliphist", "decode", item_id],
                capture_output=True,
                check=True
            )
            subprocess.run(
                ["wl-copy"],
                input=result.stdout,
                check=True
            )
            GLib.idle_add(self.close)
        except subprocess.CalledProcessError as e:
            print(f"Error pasting clipboard item: {e}", file=sys.stderr)

    def delete_item(self, item_id):
        """Delete the selected clipboard item (async)"""
        GLib.Thread.new("delete-item", self._delete_item_thread, item_id)

    def _delete_item_thread(self, item_id):
        """Background thread worker for deleting clipboard item"""
        try:
            subprocess.run(
                ["cliphist", "delete", item_id],
                check=True
            )
            self._pending_updates = True
            if not self._loading:
                GLib.Thread.new("cliphist-loader", self._load_clipboard_items_thread, None)
        except subprocess.CalledProcessError as e:
            print(f"Error deleting clipboard item: {e}", file=sys.stderr)

    def clear_history(self):
        """Clear all clipboard history (async)"""
        GLib.Thread.new("clear-history", self._clear_history_thread, None)

    def _clear_history_thread(self, user_data):
        """Background thread worker for clearing clipboard history"""
        try:
            subprocess.run(["cliphist", "wipe"], check=True)
            self._pending_updates = True
            if not self._loading:
                GLib.Thread.new("cliphist-loader", self._load_clipboard_items_thread, None)
        except subprocess.CalledProcessError as e:
            print(f"Error clearing clipboard history: {e}", file=sys.stderr)

    def filter_items(self, entry, *_):
        """Filter clipboard items based on search text"""
        self.display_clipboard_items(entry.get_text())

    def on_search_entry_key_press(self, widget, event):
        """Handle key presses in the search entry"""
        if event.keyval == Gdk.KEY_Down:
            self.move_selection(1)
            return True
        elif event.keyval == Gdk.KEY_Up:
            self.move_selection(-1)
            return True
        elif event.keyval in (Gdk.KEY_Return, Gdk.KEY_KP_Enter):
            self.use_selected_item()
            return True
        elif event.keyval == Gdk.KEY_Delete:
            self.delete_selected_item()
            return True
        elif event.keyval == Gdk.KEY_Escape:
            self.close()
            return True
        return False

    def update_selection(self, new_index):
        """Update the selected item in the viewport"""
        children = self.viewport.get_children()
        

        if self.selected_index != -1 and self.selected_index < len(children):
            current_button = children[self.selected_index]
            current_button.get_style_context().remove_class("selected")
            

        if new_index != -1 and new_index < len(children):
            new_button = children[new_index]
            new_button.get_style_context().add_class("selected")
            self.selected_index = new_index
            self.scroll_to_selected(new_button)
        else:
            self.selected_index = -1

    def move_selection(self, delta):
        """Move the selection up or down"""
        children = self.viewport.get_children()
        if not children:
            return
            

        if self.selected_index == -1 and delta == 1:
            new_index = 0
        else:
            new_index = self.selected_index + delta
            
        new_index = max(0, min(new_index, len(children) - 1))
        self.update_selection(new_index)

    def scroll_to_selected(self, button):
        """Scroll to ensure the selected item is visible"""
        def scroll():
            adj = self.scrolled_window.get_vadjustment()
            alloc = button.get_allocation()
            if alloc.height == 0:
                return False

            y = alloc.y
            height = alloc.height
            page_size = adj.get_page_size()
            current_value = adj.get_value()

            visible_top = current_value
            visible_bottom = current_value + page_size

            if y < visible_top:

                adj.set_value(y)
            elif y + height > visible_bottom:

                new_value = y + height - page_size
                adj.set_value(new_value)
            return False
        GLib.idle_add(scroll)

    def use_selected_item(self):
        """Use (paste) the selected clipboard item"""
        children = self.viewport.get_children()
        if not children or self.selected_index == -1 or self.selected_index >= len(self.clipboard_items):
            return
            

        item_line = self.clipboard_items[self.selected_index]
        item_id = item_line.split('\t', 1)[0]
        self.paste_item(item_id)

    def delete_selected_item(self):
        """Delete the selected clipboard item"""
        children = self.viewport.get_children()
        if not children or self.selected_index == -1:
            return
            

        item_line = self.clipboard_items[self.selected_index]
        item_id = item_line.split('\t', 1)[0]
        self.delete_item(item_id)

    def on_item_key_press(self, widget, event, item_id):
        """Handle key press events on clipboard items"""
        if event.keyval in (Gdk.KEY_Return, Gdk.KEY_KP_Enter):

            self.paste_item(item_id)
            return True
        return False

    def __del__(self):
        """Clean up temporary files on destruction"""
        try:
            if hasattr(self, 'tmp_dir') and os.path.exists(self.tmp_dir):
                import shutil
                shutil.rmtree(self.tmp_dir)
            self.image_cache.clear()
        except Exception as e:
            print(f"Error cleaning up temporary files: {e}", file=sys.stderr)