extends Control

# =============================================================================
# Server Browser UI
# =============================================================================
# In-game server list that fetches from the master server API and lets the
# player pick a server to connect to.
#
# Usage:
#   var browser = preload("res://client/scripts/server_browser_ui.gd").new()
#   add_child(browser)
#   browser.master_url = "http://master.example.com:28961"
#   browser.refresh()
#
# Signals:
#   server_selected(server_info: Dictionary)
#     Emitted when the player clicks "Connect" on a server.
#     The server_info dict has ip, port, name, password, etc.
# =============================================================================

signal server_selected(server_info: Dictionary)

const DEFAULT_COLUMN_WIDTHS := {
	"name": 0.30,
	"map": 0.15,
	"players": 0.10,
	"game_mode": 0.12,
	"ping": 0.08,
	"version": 0.10,
	"tags": 0.15,
}

# Configuration — set these before calling refresh()
var master_url: String = "http://127.0.0.1:28961"
var refresh_interval: float = 30.0
var auto_refresh: bool = false

# Internal state
var _http: HTTPRequest
var _refresh_timer: Timer
var _servers: Array = []
var _selected_index: int = -1
var _loading: bool = false

# UI nodes (assigned in _ready or injected)
var _panel: Panel
var _title_label: Label
var _server_list: ItemList
var _refresh_button: Button
var _connect_button: Button
var _status_label: Label
var _auto_refresh_check: CheckBox
var _filter_edit: LineEdit


func _ready() -> void:
	_build_ui()

	# HTTP request node
	_http = HTTPRequest.new()
	_http.name = "BrowserHTTP"
	_http.timeout = 10
	_http.use_threads = true
	add_child(_http)
	_http.request_completed.connect(_on_servers_received)

	# Auto-refresh timer
	_refresh_timer = Timer.new()
	_refresh_timer.name = "RefreshTimer"
	_refresh_timer.one_shot = false
	_refresh_timer.wait_time = refresh_interval
	add_child(_refresh_timer)
	_refresh_timer.timeout.connect(_do_refresh)


func _build_ui() -> void:
	# Main panel
	_panel = Panel.new()
	_panel.name = "BrowserPanel"
	_panel.anchor_right = 1.0
	_panel.anchor_bottom = 1.0
	add_child(_panel)

	var margin := 8
	var style = StyleBoxFlat.new()
	style.bg_color = Color(0.12, 0.12, 0.14, 0.95)
	style.corner_radius_top_left = 4
	style.corner_radius_top_right = 4
	style.corner_radius_bottom_left = 4
	style.corner_radius_bottom_right = 4
	style.content_margin_left = margin
	style.content_margin_top = margin
	style.content_margin_right = margin
	style.content_margin_bottom = margin
	_panel.add_theme_stylebox_override("panel", style)

	# Title
	_title_label = Label.new()
	_title_label.name = "TitleLabel"
	_title_label.text = "SERVER BROWSER"
	_title_label.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
	_title_label.add_theme_font_size_override("font_size", 18)
	_title_label.add_theme_color_override("font_color", Color(1.0, 0.84, 0.0))  # gold
	_title_label.position = Vector2(margin, margin)
	_panel.add_child(_title_label)

	# Filter
	_filter_edit = LineEdit.new()
	_filter_edit.name = "FilterEdit"
	_filter_edit.placeholder_text = "Filter by name, map, or tag..."
	_filter_edit.text_changed.connect(_on_filter_changed)
	_panel.add_child(_filter_edit)

	# Server list
	_server_list = ItemList.new()
	_server_list.name = "ServerList"
	_server_list.allow_reselect = false
	_server_list.select_mode = ItemList.SELECT_SINGLE
	_server_list.item_selected.connect(_on_server_selected)
	_server_list.nothing_selected.connect(_clear_selection)
	_panel.add_child(_server_list)

	# Buttons row
	_refresh_button = Button.new()
	_refresh_button.name = "RefreshButton"
	_refresh_button.text = "↻ Refresh"
	_refresh_button.pressed.connect(_do_refresh)
	_panel.add_child(_refresh_button)

	_connect_button = Button.new()
	_connect_button.name = "ConnectButton"
	_connect_button.text = "Connect"
	_connect_button.disabled = true
	_connect_button.pressed.connect(_on_connect_pressed)
	_panel.add_child(_connect_button)

	_auto_refresh_check = CheckBox.new()
	_auto_refresh_check.name = "AutoRefreshCheck"
	_auto_refresh_check.text = "Auto-refresh"
	_auto_refresh_check.button_pressed = auto_refresh
	_auto_refresh_check.toggled.connect(_on_auto_refresh_toggled)
	_panel.add_child(_auto_refresh_check)

	# Status bar
	_status_label = Label.new()
	_status_label.name = "StatusLabel"
	_status_label.text = "Ready"
	_status_label.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
	_status_label.add_theme_color_override("font_color", Color(0.6, 0.6, 0.6))
	_panel.add_child(_status_label)

	# Close/resize buttons
	var close_btn = Button.new()
	close_btn.name = "CloseButton"
	close_btn.text = "✕"
	close_btn.pressed.connect(_on_close_pressed)
	_panel.add_child(close_btn)


func _notification(what: int) -> void:
	if what == NOTIFICATION_RESIZED or what == NOTIFICATION_SORT_CHILDREN:
		_resize_ui()


func _resize_ui() -> void:
	var w = _panel.size.x
	var h = _panel.size.y
	var m := 8
	var y := m

	# Title
	_title_label.position = Vector2(m, y)
	_title_label.size = Vector2(w - m * 2, 24)
	y += 30

	# Filter
	_filter_edit.position = Vector2(m, y)
	_filter_edit.size = Vector2(w - m * 2, 24)
	y += 32

	# Server list
	var list_height = h - y - 80
	_server_list.position = Vector2(m, y)
	_server_list.size = Vector2(w - m * 2, max(list_height, 60))
	y += _server_list.size.y + 8

	# Buttons row
	var btn_y = y
	var btn_w = (w - m * 3) / 3

	_refresh_button.position = Vector2(m, btn_y)
	_refresh_button.size = Vector2(btn_w, 28)

	_connect_button.position = Vector2(m + btn_w + m / 2, btn_y)
	_connect_button.size = Vector2(btn_w, 28)

	_auto_refresh_check.position = Vector2(m + btn_w * 2 + m, btn_y)
	_auto_refresh_check.size = Vector2(btn_w, 28)

	y += 36

	# Status
	_status_label.position = Vector2(m, y)
	_status_label.size = Vector2(w - m * 2, 20)

	# Close button
	close_btn = _panel.get_node("CloseButton")
	close_btn.position = Vector2(w - 28, 4)
	close_btn.size = Vector2(24, 24)


func _get_close_button() -> Button:
	var node = _panel.get_node("CloseButton")
	return node as Button


# -------------------------------------------------------------------------
# Public API
# -------------------------------------------------------------------------


func refresh() -> void:
	"""Manually trigger a server list refresh."""
	_do_refresh()


func set_master_url(url: String) -> void:
	master_url = url.trim_suffix("/")
	if not master_url.begins_with("http"):
		master_url = "http://" + master_url


# -------------------------------------------------------------------------
# Internal
# -------------------------------------------------------------------------


func _do_refresh() -> void:
	if _loading:
		return
	_loading = true
	_status_label.text = "Fetching servers..."
	_refresh_button.disabled = true

	var endpoint = master_url + "/api/v1/servers"
	var err = _http.request(endpoint, [], HTTPClient.METHOD_GET)
	if err != OK:
		_status_label.text = "Failed to send request (error " + str(err) + ")"
		_loading = false
		_refresh_button.disabled = false


func _on_servers_received(result: int, response_code: int, _headers: PackedStringArray, body: PackedByteArray) -> void:
	_loading = false
	_refresh_button.disabled = false

	if result != HTTPRequest.RESULT_SUCCESS:
		_status_label.text = "Network error " + str(result)
		return

	if response_code != 200:
		_status_label.text = "Server error (HTTP " + str(response_code) + ")"
		return

	var body_text = body.get_string_from_utf8()
	var json = JSON.new()
	var parse_err = json.parse(body_text)
	if parse_err != OK or not (json.data is Dictionary):
		_status_label.text = "Invalid response from master server"
		return

	var data = json.data as Dictionary
	_servers = data.get("servers", []) as Array
	_populate_list()
	_status_label.text = str(_servers.size()) + " server(s) found"

	# Start auto-refresh timer if supposed to
	if auto_refresh and not _refresh_timer.is_stopped():
		_refresh_timer.start()


func _populate_list() -> void:
	_server_list.clear()

	var filter_text = _filter_edit.text.strip_edges().to_lower()

	for srv in _servers:
		if not (srv is Dictionary):
			continue

		# Apply filter
		if not filter_text.is_empty():
			var match_found = false
			for field in ["name", "map", "tags", "game_mode"]:
				var val = _get_str(srv, field, "")
				if val.to_lower().contains(filter_text):
					match_found = true
					break
			if not match_found:
				continue

		var name = _get_str(srv, "name", "Unnamed")
		var map_name = _get_str(srv, "map", "?")
		var players = _get_int(srv, "players", 0)
		var max_players = _get_int(srv, "max_players", 16)
		var mode = _get_str(srv, "game_mode", "?")
		var version = _get_str(srv, "version", "?")
		var tags = _get_str(srv, "tags", "")
		var has_pass = _get_bool(srv, "password", false)

		# Format: "Server Name                              dust2    8/16  DM  v1.0  eu,ranked"
		var pass_mark = "🔒" if has_pass else " "
		var tag_str = ""
		if tags is Array:
			tag_str = ",".join(tags)
		elif tags is String:
			tag_str = tags

		var label = pass_mark + " " + name
		# Pad fields with spaces
		label += " " + _pad_right(map_name, 14)
		label += str(players) + "/" + str(max_players) + " "
		label += _pad_right(mode, 10)
		label += version + " "
		label += tag_str

		_server_list.add_item(label)

	_connect_button.disabled = true
	_selected_index = -1


func _on_server_selected(index: int) -> void:
	_selected_index = index
	_connect_button.disabled = index < 0


func _clear_selection() -> void:
	_selected_index = -1
	_connect_button.disabled = true


func _on_connect_pressed() -> void:
	if _selected_index < 0 or _selected_index >= _servers.size():
		return

	var srv = _servers[_selected_index] as Dictionary
	var host = _get_str(srv, "host", "")
	var port = _get_int(srv, "port", 0)

	if host.is_empty() or port == 0:
		_status_label.text = "ERROR: Server has no address info"
		return

	emit_signal("server_selected", srv)


func _on_filter_changed(_new_text: String) -> void:
	_populate_list()


func _on_auto_refresh_toggled(enabled: bool) -> void:
	auto_refresh = enabled
	if enabled:
		_refresh_timer.wait_time = refresh_interval
		_refresh_timer.start()
	else:
		_refresh_timer.stop()


func _on_close_pressed() -> void:
	_refresh_timer.stop()
	queue_free()


# -------------------------------------------------------------------------
# Helpers
# -------------------------------------------------------------------------

static func _get_str(d: Dictionary, key: String, fallback: String) -> String:
	var val = d.get(key, fallback)
	if val is String:
		return val
	return str(val)


static func _get_int(d: Dictionary, key: String, fallback: int) -> int:
	var val = d.get(key, fallback)
	if val is int:
		return val
	if val is float:
		return int(val)
	if val is String:
		return val.to_int()
	return fallback


static func _get_bool(d: Dictionary, key: String, fallback: bool) -> bool:
	var val = d.get(key, fallback)
	if val is bool:
		return val
	if val is int:
		return val != 0
	return fallback


static func _pad_right(text: String, min_width: int) -> String:
	var result = text
	while result.length() < min_width:
		result += " "
	return result