import os.path
import tkinter as tk
from tkinter import ttk

from thonny.ui_utils import TreeFrame
from thonny import misc_utils
from thonny.globals import get_workbench


_dummy_node_text = "..."
    


class BaseFileBrowser(TreeFrame):
    def __init__(self, master, show_hidden_files=False, last_folder_setting_name=None): 
        TreeFrame.__init__(self, master, 
                           ["#0", "kind", "path"], 
                           displaycolumns=(0,))
        #print(self.get_toplevel_items())
        
        self.show_hidden_files = show_hidden_files
        self.tree['show'] = ('tree',)
        
        self.hor_scrollbar = ttk.Scrollbar(self, orient=tk.HORIZONTAL)
        self.tree.config(xscrollcommand=self.hor_scrollbar.set)
        self.hor_scrollbar['command'] = self.tree.xview
        self.hor_scrollbar.grid(row=1, column=0, sticky="nsew")
        
        wb = get_workbench()
        self.folder_icon = wb.get_image("folder.gif")
        self.python_file_icon = wb.get_image("python_file.gif")
        self.text_file_icon = wb.get_image("text_file.gif")
        self.generic_file_icon = wb.get_image("generic_file.gif")
        self.hard_drive_icon = wb.get_image("hard_drive2.gif")
        
        self.tree.column('#0', width=500, anchor=tk.W)
        
        # set-up root node
        self.tree.set("", "kind", "root")
        self.tree.set("", "path", "")
        self.refresh_tree()
        
        
        self.tree.bind("<<TreeviewOpen>>", self.on_open_node)
        
        self._last_folder_setting_name = last_folder_setting_name
        self.open_initial_folder()
    
    def open_initial_folder(self):
        if self._last_folder_setting_name:
            path = get_workbench().get_option(self._last_folder_setting_name)
            if path:
                self.open_path_in_browser(path, True)
    
    def save_current_folder(self):
        if not self._last_folder_setting_name:
            return
        
        path = self.get_selected_path()
        
        if not path:
            return
        
        if os.path.isfile(path):
            path = os.path.dirname(path)
        get_workbench().set_option(self._last_folder_setting_name, path)
    
    def on_open_node(self, event):
        node_id = self.get_selected_node()
        if node_id:
            self.refresh_tree(node_id, True)
    

    
    def get_selected_node(self):
        nodes = self.tree.selection()
        assert len(nodes) <= 1
        if len(nodes) == 1:
            return nodes[0]
        else:
            return None
    
    def get_selected_path(self):
        node_id = self.get_selected_node()
        
        if node_id:
            return self.tree.set(node_id, "path")
        else:
            return None
    
    def open_path_in_browser(self, path, see=True):
        
        # unfortunately os.path.split splits from the wrong end (for this case)
        def split(path):
            head, tail = os.path.split(path)
            if head == "" and tail == "":
                return []
            elif head == path or tail == path:
                return [path]
            elif head == "":
                return [tail]
            elif tail == "":
                return split(head)
            else:
                return split(head) + [tail]
        
        parts = split(path)
        current_node_id = ""
        current_path = ""
        
        while parts != []:
            current_path = os.path.join(current_path, parts.pop(0))
            
            for child_id in self.tree.get_children(current_node_id):
                child_path = self.tree.set(child_id, "path")
                if child_path == current_path:
                    self.tree.item(child_id, open=True)
                    self.refresh_tree(child_id)
                    current_node_id = child_id
                    break
        
        if see:
            self.tree.selection_set(current_node_id)
            self.tree.focus(current_node_id)
            
            if self.tree.set(current_node_id, "kind") == "file":
                self.tree.see(self.tree.parent(current_node_id))
            else:
                self.tree.see(current_node_id)    
                
    
    def populate_tree(self):
        for path in self.get_toplevel_items():
            self.show_item(path, path, "", 2)
    
    def refresh_tree(self, node_id="", opening=None):
        path = self.tree.set(node_id, "path")
        #print("REFRESH", path)
        
        if os.path.isfile(path):
            self.tree.set_children(node_id)
            self.tree.item(node_id, open=False)
        else:
            # either root or directory
            if node_id == "" or self.tree.item(node_id, "open") or opening == True:
                fs_children_names = self.listdir(path, self.show_hidden_files)
                tree_children_ids = self.tree.get_children(node_id) 
                
                # recollect children
                children = {}
                
                # first the ones, which are present already in tree
                for child_id in tree_children_ids:
                    name = self.tree.item(child_id, "text")
                    if name in fs_children_names:
                        children[name] = child_id
                
                # add missing children
                for name in fs_children_names:
                    if name not in children:
                        children[name] = self.tree.insert(node_id, "end")
                        self.tree.set(children[name], "path", os.path.join(path, name))
                        
                
                def file_order(name):
                    # items in a folder should be ordered so that 
                    # folders come first and names are ordered case insensitively
                    return (os.path.isfile(os.path.join(path, name)),
                            name.upper())
                
                # update tree
                ids_sorted_by_name = list(map(lambda key: children[key],
                                              sorted(children.keys(), key=file_order)))
                self.tree.set_children(node_id, *ids_sorted_by_name)
                
                for child_id in ids_sorted_by_name:
                    self.update_node_format(child_id)
                    self.refresh_tree(child_id)
                
            else:
                # closed dir
                # Don't fetch children yet, but ensure that expand button is visible
                children_ids = self.tree.get_children(node_id)
                if len(children_ids) == 0:
                    self.tree.insert(node_id, "end", text=_dummy_node_text) 
    
    def update_node_format(self, node_id):
        assert node_id != ""
        
        path = self.tree.set(node_id, "path")
        
        
        if os.path.isdir(path) or path.endswith(":") or path.endswith(":\\"):
            self.tree.set(node_id, "kind", "dir")
            if path.endswith(":") or path.endswith(":\\"):
                img = self.hard_drive_icon
            else:
                img = self.folder_icon
        else:
            self.tree.set(node_id, "kind", "file")
            if path.lower().endswith(".py"):
                img = self.python_file_icon
            elif path.lower().endswith(".txt") or path.lower().endswith(".csv"):
                img = self.text_file_icon
            else:
                img = self.generic_file_icon
            
        # compute caption 
        text = os.path.basename(path)
        if text == "": # in case of drive roots 
            text = path
            
        self.tree.item(node_id, text=" " + text, image=img)
        self.tree.set(node_id, "path", path)
    
    def listdir(self, path="", include_hidden_files=False):
        
        if path == "" and misc_utils.running_on_windows():
            result = misc_utils.get_win_drives()
        else:
            if path == "":
                first_level = True
                path = "/"
            else:
                first_level = False
            result = [x for x in os.listdir(path) 
                        if include_hidden_files 
                            or not misc_utils.is_hidden_or_system_file(os.path.join(path, x))]
            
            if first_level:
                result = ["/" + x for x in result]
            
        return sorted(result, key=str.upper)
