/*************************************************************************/
/*  version_control_editor_plugin.cpp                                    */
/*************************************************************************/
/*                       This file is part of:                           */
/*                           GODOT ENGINE                                */
/*                      https://godotengine.org                          */
/*************************************************************************/
/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur.                 */
/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md).   */
/*                                                                       */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the       */
/* "Software"), to deal in the Software without restriction, including   */
/* without limitation the rights to use, copy, modify, merge, publish,   */
/* distribute, sublicense, and/or sell copies of the Software, and to    */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions:                                             */
/*                                                                       */
/* The above copyright notice and this permission notice shall be        */
/* included in all copies or substantial portions of the Software.       */
/*                                                                       */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
/*************************************************************************/

#include "version_control_editor_plugin.h"

#include "core/object/script_language.h"
#include "core/os/keyboard.h"
#include "editor/editor_file_system.h"
#include "editor/editor_node.h"
#include "editor/editor_scale.h"

VersionControlEditorPlugin *VersionControlEditorPlugin::singleton = nullptr;

void VersionControlEditorPlugin::_bind_methods() {
	ClassDB::bind_method(D_METHOD("popup_vcs_set_up_dialog"), &VersionControlEditorPlugin::popup_vcs_set_up_dialog);

	// Used to track the status of files in the staging area
	BIND_ENUM_CONSTANT(CHANGE_TYPE_NEW);
	BIND_ENUM_CONSTANT(CHANGE_TYPE_MODIFIED);
	BIND_ENUM_CONSTANT(CHANGE_TYPE_RENAMED);
	BIND_ENUM_CONSTANT(CHANGE_TYPE_DELETED);
	BIND_ENUM_CONSTANT(CHANGE_TYPE_TYPECHANGE);
}

void VersionControlEditorPlugin::_selected_a_vcs(int p_id) {
	List<StringName> available_addons = get_available_vcs_names();
	const StringName selected_vcs = set_up_choice->get_item_text(p_id);
}

void VersionControlEditorPlugin::_populate_available_vcs_names() {
	static bool called = false;

	if (!called) {
		List<StringName> available_addons = get_available_vcs_names();
		for (int i = 0; i < available_addons.size(); i++) {
			set_up_choice->add_item(available_addons[i]);
		}

		called = true;
	}
}

VersionControlEditorPlugin *VersionControlEditorPlugin::get_singleton() {
	return singleton ? singleton : memnew(VersionControlEditorPlugin);
}

void VersionControlEditorPlugin::popup_vcs_set_up_dialog(const Control *p_gui_base) {
	fetch_available_vcs_addon_names();
	List<StringName> available_addons = get_available_vcs_names();
	if (available_addons.size() >= 1) {
		Size2 popup_size = Size2(400, 100);
		Size2 window_size = p_gui_base->get_viewport_rect().size;
		popup_size.x = MIN(window_size.x * 0.5, popup_size.x);
		popup_size.y = MIN(window_size.y * 0.5, popup_size.y);

		_populate_available_vcs_names();

		set_up_dialog->popup_centered_clamped(popup_size * EDSCALE);
	} else {
		EditorNode::get_singleton()->show_warning(TTR("No VCS addons are available."), TTR("Error"));
	}
}

void VersionControlEditorPlugin::_initialize_vcs() {
	register_editor();

	ERR_FAIL_COND_MSG(EditorVCSInterface::get_singleton(), EditorVCSInterface::get_singleton()->get_vcs_name() + " is already active");

	const int id = set_up_choice->get_selected_id();
	String selected_addon = set_up_choice->get_item_text(id);

	String path = ScriptServer::get_global_class_path(selected_addon);
	Ref<Script> script = ResourceLoader::load(path);

	ERR_FAIL_COND_MSG(!script.is_valid(), "VCS Addon path is invalid");

	EditorVCSInterface *vcs_interface = memnew(EditorVCSInterface);
	ScriptInstance *addon_script_instance = script->instance_create(vcs_interface);

	ERR_FAIL_COND_MSG(!addon_script_instance, "Failed to create addon script instance.");

	// The addon is attached as a script to the VCS interface as a proxy end-point
	vcs_interface->set_script_and_instance(script, addon_script_instance);

	EditorVCSInterface::set_singleton(vcs_interface);
	EditorFileSystem::get_singleton()->connect("filesystem_changed", callable_mp(this, &VersionControlEditorPlugin::_refresh_stage_area));

	String res_dir = OS::get_singleton()->get_resource_dir();

	ERR_FAIL_COND_MSG(!EditorVCSInterface::get_singleton()->initialize(res_dir), "VCS was not initialized");

	_refresh_stage_area();
}

void VersionControlEditorPlugin::_send_commit_msg() {
	if (EditorVCSInterface::get_singleton()) {
		if (staged_files_count == 0) {
			commit_status->set_text(TTR("No files added to stage"));
			return;
		}

		EditorVCSInterface::get_singleton()->commit(commit_message->get_text());

		commit_message->set_text("");
		version_control_dock_button->set_pressed(false);
	} else {
		WARN_PRINT("No VCS addon is initialized. Select a Version Control Addon from Project menu");
	}

	_update_commit_status();
	_refresh_stage_area();
	_clear_file_diff();
}

void VersionControlEditorPlugin::_refresh_stage_area() {
	if (EditorVCSInterface::get_singleton()) {
		staged_files_count = 0;
		clear_stage_area();

		Dictionary modified_file_paths = EditorVCSInterface::get_singleton()->get_modified_files_data();
		String file_path;
		for (int i = 0; i < modified_file_paths.size(); i++) {
			file_path = modified_file_paths.get_key_at_index(i);
			TreeItem *found = stage_files->search_item_text(file_path, nullptr, true);
			if (!found) {
				ChangeType change_index = (ChangeType)(int)modified_file_paths.get_value_at_index(i);
				String change_text = file_path + " (" + change_type_to_strings[change_index] + ")";
				Color &change_color = change_type_to_color[change_index];
				TreeItem *new_item = stage_files->create_item(stage_files->get_root());
				new_item->set_cell_mode(0, TreeItem::CELL_MODE_CHECK);
				new_item->set_text(0, change_text);
				new_item->set_metadata(0, file_path);
				new_item->set_custom_color(0, change_color);
				new_item->set_checked(0, true);
				new_item->set_editable(0, true);
			} else {
				if (found->get_metadata(0) == diff_file_name->get_text()) {
					_refresh_file_diff();
				}
			}
			commit_status->set_text(TTR("New changes detected"));
		}
	} else {
		WARN_PRINT("No VCS addon is initialized. Select a Version Control Addon from Project menu.");
	}
}

void VersionControlEditorPlugin::_stage_selected() {
	if (!EditorVCSInterface::get_singleton()) {
		WARN_PRINT("No VCS addon is initialized. Select a Version Control Addon from Project menu");
		return;
	}

	staged_files_count = 0;
	TreeItem *root = stage_files->get_root();
	if (root) {
		TreeItem *file_entry = root->get_first_child();
		while (file_entry) {
			if (file_entry->is_checked(0)) {
				EditorVCSInterface::get_singleton()->stage_file(file_entry->get_metadata(0));
				file_entry->set_icon_modulate(0, EditorNode::get_singleton()->get_gui_base()->get_theme_color(SNAME("success_color"), SNAME("Editor")));
				staged_files_count++;
			} else {
				EditorVCSInterface::get_singleton()->unstage_file(file_entry->get_metadata(0));
				file_entry->set_icon_modulate(0, EditorNode::get_singleton()->get_gui_base()->get_theme_color(SNAME("error_color"), SNAME("Editor")));
			}

			file_entry = file_entry->get_next();
		}
	}

	_update_stage_status();
}

void VersionControlEditorPlugin::_stage_all() {
	if (!EditorVCSInterface::get_singleton()) {
		WARN_PRINT("No VCS addon is initialized. Select a Version Control Addon from Project menu");
		return;
	}

	staged_files_count = 0;
	TreeItem *root = stage_files->get_root();
	if (root) {
		TreeItem *file_entry = root->get_first_child();
		while (file_entry) {
			EditorVCSInterface::get_singleton()->stage_file(file_entry->get_metadata(0));
			file_entry->set_icon_modulate(0, EditorNode::get_singleton()->get_gui_base()->get_theme_color(SNAME("success_color"), SNAME("Editor")));
			file_entry->set_checked(0, true);
			staged_files_count++;

			file_entry = file_entry->get_next();
		}
	}

	_update_stage_status();
}

void VersionControlEditorPlugin::_view_file_diff() {
	version_control_dock_button->set_pressed(true);

	String file_path = stage_files->get_selected()->get_metadata(0);

	_display_file_diff(file_path);
}

void VersionControlEditorPlugin::_display_file_diff(String p_file_path) {
	Array diff_content = EditorVCSInterface::get_singleton()->get_file_diff(p_file_path);

	diff_file_name->set_text(p_file_path);

	diff->clear();
	diff->push_font(EditorNode::get_singleton()->get_gui_base()->get_theme_font(SNAME("source"), SNAME("EditorFonts")));
	for (int i = 0; i < diff_content.size(); i++) {
		Dictionary line_result = diff_content[i];

		if (line_result["status"] == "+") {
			diff->push_color(EditorNode::get_singleton()->get_gui_base()->get_theme_color(SNAME("success_color"), SNAME("Editor")));
		} else if (line_result["status"] == "-") {
			diff->push_color(EditorNode::get_singleton()->get_gui_base()->get_theme_color(SNAME("error_color"), SNAME("Editor")));
		} else {
			diff->push_color(EditorNode::get_singleton()->get_gui_base()->get_theme_color(SNAME("font_color"), SNAME("Label")));
		}

		diff->add_text((String)line_result["content"]);

		diff->pop();
	}
	diff->pop();
}

void VersionControlEditorPlugin::_refresh_file_diff() {
	String open_file = diff_file_name->get_text();
	if (open_file != "") {
		_display_file_diff(diff_file_name->get_text());
	}
}

void VersionControlEditorPlugin::_clear_file_diff() {
	diff->clear();
	diff_file_name->set_text("");
	version_control_dock_button->set_pressed(false);
}

void VersionControlEditorPlugin::_update_stage_status() {
	String status;
	if (staged_files_count == 1) {
		status = TTR("Stage contains 1 file");
	} else {
		status = vformat(TTR("Stage contains %d files"), staged_files_count);
	}
	commit_status->set_text(status);
}

void VersionControlEditorPlugin::_update_commit_status() {
	String status;
	if (staged_files_count == 1) {
		status = TTR("Committed 1 file");
	} else {
		status = vformat(TTR("Committed %d files"), staged_files_count);
	}
	commit_status->set_text(status);
	staged_files_count = 0;
}

void VersionControlEditorPlugin::_update_commit_button() {
	commit_button->set_disabled(commit_message->get_text().strip_edges() == "");
}

void VersionControlEditorPlugin::_commit_message_gui_input(const Ref<InputEvent> &p_event) {
	if (!commit_message->has_focus()) {
		return;
	}
	if (commit_message->get_text().strip_edges().is_empty()) {
		// Do not allow empty commit messages.
		return;
	}
	const Ref<InputEventKey> k = p_event;

	if (k.is_valid() && k->is_pressed()) {
		if (ED_IS_SHORTCUT("version_control/commit", p_event)) {
			if (staged_files_count == 0) {
				// Stage all files only when no files were previously staged.
				_stage_all();
			}
			_send_commit_msg();
			commit_message->accept_event();
			return;
		}
	}
}

void VersionControlEditorPlugin::register_editor() {
	if (!EditorVCSInterface::get_singleton()) {
		EditorNode::get_singleton()->add_control_to_dock(EditorNode::DOCK_SLOT_RIGHT_UL, version_commit_dock);
		TabContainer *dock_vbc = (TabContainer *)version_commit_dock->get_parent_control();
		dock_vbc->set_tab_title(version_commit_dock->get_index(), TTR("Commit"));

		Button *vc = EditorNode::get_singleton()->add_bottom_panel_item(TTR("Version Control"), version_control_dock);
		set_version_control_tool_button(vc);
	}
}

void VersionControlEditorPlugin::fetch_available_vcs_addon_names() {
	List<StringName> global_classes;
	ScriptServer::get_global_class_list(&global_classes);

	for (int i = 0; i != global_classes.size(); i++) {
		String path = ScriptServer::get_global_class_path(global_classes[i]);
		Ref<Script> script = ResourceLoader::load(path);
		ERR_FAIL_COND(script.is_null());

		if (script->get_instance_base_type() == "EditorVCSInterface") {
			available_addons.push_back(global_classes[i]);
		}
	}
}

void VersionControlEditorPlugin::clear_stage_area() {
	stage_files->get_root()->clear_children();
}

void VersionControlEditorPlugin::shut_down() {
	if (EditorVCSInterface::get_singleton()) {
		if (EditorFileSystem::get_singleton()->is_connected("filesystem_changed", callable_mp(this, &VersionControlEditorPlugin::_refresh_stage_area))) {
			EditorFileSystem::get_singleton()->disconnect("filesystem_changed", callable_mp(this, &VersionControlEditorPlugin::_refresh_stage_area));
		}
		EditorVCSInterface::get_singleton()->shut_down();
		memdelete(EditorVCSInterface::get_singleton());
		EditorVCSInterface::set_singleton(nullptr);

		EditorNode::get_singleton()->remove_control_from_dock(version_commit_dock);
		EditorNode::get_singleton()->remove_bottom_panel_item(version_control_dock);
	}
}

bool VersionControlEditorPlugin::is_vcs_initialized() const {
	return EditorVCSInterface::get_singleton() ? EditorVCSInterface::get_singleton()->is_vcs_initialized() : false;
}

const String VersionControlEditorPlugin::get_vcs_name() const {
	return EditorVCSInterface::get_singleton() ? EditorVCSInterface::get_singleton()->get_vcs_name() : "";
}

VersionControlEditorPlugin::VersionControlEditorPlugin() {
	singleton = this;
	staged_files_count = 0;

	version_control_actions = memnew(PopupMenu);

	set_up_dialog = memnew(AcceptDialog);
	set_up_dialog->set_title(TTR("Set Up Version Control"));
	set_up_dialog->set_min_size(Size2(400, 100));
	version_control_actions->add_child(set_up_dialog);

	set_up_ok_button = set_up_dialog->get_ok_button();
	set_up_ok_button->set_text(TTR("Close"));

	set_up_vbc = memnew(VBoxContainer);
	set_up_vbc->set_alignment(VBoxContainer::ALIGN_CENTER);
	set_up_dialog->add_child(set_up_vbc);

	set_up_hbc = memnew(HBoxContainer);
	set_up_hbc->set_h_size_flags(HBoxContainer::SIZE_EXPAND_FILL);
	set_up_vbc->add_child(set_up_hbc);

	set_up_vcs_status = memnew(RichTextLabel);
	set_up_vcs_status->set_text(TTR("VCS Addon is not initialized"));
	set_up_vbc->add_child(set_up_vcs_status);

	set_up_vcs_label = memnew(Label);
	set_up_vcs_label->set_text(TTR("Version Control System"));
	set_up_hbc->add_child(set_up_vcs_label);

	set_up_choice = memnew(OptionButton);
	set_up_choice->set_h_size_flags(HBoxContainer::SIZE_EXPAND_FILL);
	set_up_choice->connect("item_selected", callable_mp(this, &VersionControlEditorPlugin::_selected_a_vcs));
	set_up_hbc->add_child(set_up_choice);

	set_up_init_settings = nullptr;

	set_up_init_button = memnew(Button);
	set_up_init_button->set_text(TTR("Initialize"));
	set_up_init_button->connect("pressed", callable_mp(this, &VersionControlEditorPlugin::_initialize_vcs));
	set_up_vbc->add_child(set_up_init_button);

	version_commit_dock = memnew(VBoxContainer);
	version_commit_dock->set_visible(false);

	commit_box_vbc = memnew(VBoxContainer);
	commit_box_vbc->set_alignment(VBoxContainer::ALIGN_BEGIN);
	commit_box_vbc->set_h_size_flags(VBoxContainer::SIZE_EXPAND_FILL);
	commit_box_vbc->set_v_size_flags(VBoxContainer::SIZE_EXPAND_FILL);
	version_commit_dock->add_child(commit_box_vbc);

	stage_tools = memnew(HSplitContainer);
	stage_tools->set_dragger_visibility(SplitContainer::DRAGGER_HIDDEN_COLLAPSED);
	commit_box_vbc->add_child(stage_tools);

	staging_area_label = memnew(Label);
	staging_area_label->set_h_size_flags(Label::SIZE_EXPAND_FILL);
	staging_area_label->set_text(TTR("Staging area"));
	stage_tools->add_child(staging_area_label);

	refresh_button = memnew(Button);
	refresh_button->set_tooltip(TTR("Detect new changes"));
	refresh_button->set_text(TTR("Refresh"));
	refresh_button->set_icon(EditorNode::get_singleton()->get_gui_base()->get_theme_icon(SNAME("Reload"), SNAME("EditorIcons")));
	refresh_button->connect("pressed", callable_mp(this, &VersionControlEditorPlugin::_refresh_stage_area));
	stage_tools->add_child(refresh_button);

	stage_files = memnew(Tree);
	stage_files->set_h_size_flags(Tree::SIZE_EXPAND_FILL);
	stage_files->set_v_size_flags(Tree::SIZE_EXPAND_FILL);
	stage_files->set_columns(1);
	stage_files->set_column_title(0, TTR("Changes"));
	stage_files->set_column_titles_visible(true);
	stage_files->set_allow_reselect(true);
	stage_files->set_allow_rmb_select(true);
	stage_files->set_select_mode(Tree::SelectMode::SELECT_MULTI);
	stage_files->set_edit_checkbox_cell_only_when_checkbox_is_pressed(true);
	stage_files->connect("cell_selected", callable_mp(this, &VersionControlEditorPlugin::_view_file_diff));
	stage_files->create_item();
	stage_files->set_hide_root(true);
	commit_box_vbc->add_child(stage_files);

	change_type_to_strings[CHANGE_TYPE_NEW] = TTR("New");
	change_type_to_strings[CHANGE_TYPE_MODIFIED] = TTR("Modified");
	change_type_to_strings[CHANGE_TYPE_RENAMED] = TTR("Renamed");
	change_type_to_strings[CHANGE_TYPE_DELETED] = TTR("Deleted");
	change_type_to_strings[CHANGE_TYPE_TYPECHANGE] = TTR("Typechange");

	change_type_to_color[CHANGE_TYPE_NEW] = EditorNode::get_singleton()->get_gui_base()->get_theme_color(SNAME("success_color"), SNAME("Editor"));
	change_type_to_color[CHANGE_TYPE_MODIFIED] = EditorNode::get_singleton()->get_gui_base()->get_theme_color(SNAME("warning_color"), SNAME("Editor"));
	change_type_to_color[CHANGE_TYPE_RENAMED] = EditorNode::get_singleton()->get_gui_base()->get_theme_color(SNAME("disabled_font_color"), SNAME("Editor"));
	change_type_to_color[CHANGE_TYPE_DELETED] = EditorNode::get_singleton()->get_gui_base()->get_theme_color(SNAME("error_color"), SNAME("Editor"));
	change_type_to_color[CHANGE_TYPE_TYPECHANGE] = EditorNode::get_singleton()->get_gui_base()->get_theme_color(SNAME("font_color"), SNAME("Editor"));

	stage_buttons = memnew(HSplitContainer);
	stage_buttons->set_dragger_visibility(SplitContainer::DRAGGER_HIDDEN_COLLAPSED);
	commit_box_vbc->add_child(stage_buttons);

	stage_selected_button = memnew(Button);
	stage_selected_button->set_h_size_flags(Button::SIZE_EXPAND_FILL);
	stage_selected_button->set_text(TTR("Stage Selected"));
	stage_selected_button->connect("pressed", callable_mp(this, &VersionControlEditorPlugin::_stage_selected));
	stage_buttons->add_child(stage_selected_button);

	stage_all_button = memnew(Button);
	stage_all_button->set_text(TTR("Stage All"));
	stage_all_button->connect("pressed", callable_mp(this, &VersionControlEditorPlugin::_stage_all));
	stage_buttons->add_child(stage_all_button);

	commit_box_vbc->add_child(memnew(HSeparator));

	commit_message = memnew(TextEdit);
	commit_message->set_h_size_flags(Control::SIZE_EXPAND_FILL);
	commit_message->set_h_grow_direction(Control::GrowDirection::GROW_DIRECTION_BEGIN);
	commit_message->set_v_grow_direction(Control::GrowDirection::GROW_DIRECTION_END);
	commit_message->set_custom_minimum_size(Size2(200, 100));
	commit_message->set_line_wrapping_mode(TextEdit::LineWrappingMode::LINE_WRAPPING_BOUNDARY);
	commit_message->connect("text_changed", callable_mp(this, &VersionControlEditorPlugin::_update_commit_button));
	commit_message->connect("gui_input", callable_mp(this, &VersionControlEditorPlugin::_commit_message_gui_input));
	commit_box_vbc->add_child(commit_message);
	ED_SHORTCUT("version_control/commit", TTR("Commit"), KEY_MASK_CMD | KEY_ENTER);

	commit_button = memnew(Button);
	commit_button->set_text(TTR("Commit Changes"));
	commit_button->set_disabled(true);
	commit_button->connect("pressed", callable_mp(this, &VersionControlEditorPlugin::_send_commit_msg));
	commit_box_vbc->add_child(commit_button);

	commit_status = memnew(Label);
	commit_status->set_align(Label::ALIGN_CENTER);
	commit_box_vbc->add_child(commit_status);

	version_control_dock = memnew(PanelContainer);
	version_control_dock->set_v_size_flags(Control::SIZE_EXPAND_FILL);
	version_control_dock->set_custom_minimum_size(Size2(0, 300) * EDSCALE);
	version_control_dock->hide();

	diff_vbc = memnew(VBoxContainer);
	diff_vbc->set_h_size_flags(HBoxContainer::SIZE_FILL);
	diff_vbc->set_v_size_flags(HBoxContainer::SIZE_FILL);
	version_control_dock->add_child(diff_vbc);

	diff_hbc = memnew(HBoxContainer);
	diff_hbc->set_h_size_flags(HBoxContainer::SIZE_FILL);
	diff_vbc->add_child(diff_hbc);

	diff_heading = memnew(Label);
	diff_heading->set_text(TTR("Status"));
	diff_heading->set_tooltip(TTR("View file diffs before committing them to the latest version"));
	diff_hbc->add_child(diff_heading);

	diff_file_name = memnew(Label);
	diff_file_name->set_text(TTR("No file diff is active"));
	diff_file_name->set_h_size_flags(Label::SIZE_EXPAND_FILL);
	diff_file_name->set_align(Label::ALIGN_RIGHT);
	diff_hbc->add_child(diff_file_name);

	diff_refresh_button = memnew(Button);
	diff_refresh_button->set_tooltip(TTR("Detect changes in file diff"));
	diff_refresh_button->set_icon(EditorNode::get_singleton()->get_gui_base()->get_theme_icon(SNAME("Reload"), SNAME("EditorIcons")));
	diff_refresh_button->connect("pressed", callable_mp(this, &VersionControlEditorPlugin::_refresh_file_diff));
	diff_hbc->add_child(diff_refresh_button);

	diff = memnew(RichTextLabel);
	diff->set_h_size_flags(TextEdit::SIZE_EXPAND_FILL);
	diff->set_v_size_flags(TextEdit::SIZE_EXPAND_FILL);
	diff->set_selection_enabled(true);
	diff_vbc->add_child(diff);
}

VersionControlEditorPlugin::~VersionControlEditorPlugin() {
	shut_down();
	memdelete(version_control_dock);
	memdelete(version_commit_dock);
	memdelete(version_control_actions);
}