"""Keyboard input modes for TUI pages (navigation vs text entry)."""

from __future__ import annotations

from dataclasses import dataclass
from typing import TYPE_CHECKING, Literal, Protocol

from pygittools.tui.changes_list import ChangesList
from pygittools.tui.keys import KeyLike, is_down, is_enter, is_esc, is_left, is_right, is_up
from pygittools.tui.log_list import CommitLogList
from pygittools.tui.pages.actions import actions_page
from pygittools.tui.pages.branches import branch_picker_page
from pygittools.tui.pages.help import help_page
from pygittools.tui.pages.projects import projects_page
from pygittools.tui.pages.worktree_add import worktree_add_page
from pygittools.tui.types import PageAction, PageContext, PageResult

if TYPE_CHECKING:
	from pygittools.tui.tasks_list import TasksBoardList
	from pygittools.tui.worktrees_list import WorktreesList

_HeaderFocus = Literal["changes", "repo", "branch", "actions"]
_HomeTab = Literal["status", "log", "tasks", "worktrees"]


@dataclass(frozen=True, slots=True)
class ContextDispatch:
	page_result: PageResult | None = None
	next_mode: Literal["nav", "input"] | None = None


class PageInputHost(Protocol):
	@property
	def header_focus(self) -> _HeaderFocus: ...

	def set_header_focus(self, focus: _HeaderFocus) -> None: ...

	@property
	def page_context(self) -> PageContext | None: ...

	@property
	def changes(self) -> ChangesList: ...

	@property
	def log(self) -> CommitLogList: ...

	@property
	def active_tab(self) -> _HomeTab: ...

	def set_active_tab(self, tab: _HomeTab) -> None: ...

	@property
	def tasks(self) -> TasksBoardList: ...

	@property
	def worktrees(self) -> WorktreesList: ...

	@property
	def has_actions(self) -> bool: ...


class NavContext:
	def status_hint(self, host: PageInputHost) -> str:
		if host.header_focus == "repo":
			return "Enter browse projects — j/k move — H/L switch tab"
		if host.header_focus == "branch":
			if host.active_tab == "tasks":
				return "Enter sync tasks — j/k move — H/L switch tab"
			if host.active_tab == "worktrees":
				return "Enter add worktree — j/k move — H/L switch tab"
			return "Enter switch branch — j/k move — H/L switch tab"
		if host.header_focus == "actions":
			if host.has_actions:
				return "Enter open actions — j/k move — H/L switch tab"
			return "No action groups — j/k move — H/L switch tab"
		if host.active_tab == "log":
			return host.log.status_hint()
		if host.active_tab == "tasks":
			return host.tasks.status_hint()
		if host.active_tab == "worktrees":
			return host.worktrees.status_hint()
		return host.changes.status_hint()

	def dispatch_key(self, host: PageInputHost, key: KeyLike) -> ContextDispatch:
		if _try_switch_tab(host, key):
			return ContextDispatch()

		if key.code == "?":
			return ContextDispatch(page_result=PageResult(action=PageAction.PUSH, next_page=help_page()))
		if key.code == "!":
			return ContextDispatch(page_result=PageResult(action=PageAction.PUSH, next_page=actions_page()))

		if host.header_focus == "repo":
			if is_down(key):
				host.set_header_focus("branch")
			elif is_enter(key):
				return ContextDispatch(page_result=PageResult(action=PageAction.PUSH, next_page=projects_page()))
			return ContextDispatch()

		if host.header_focus == "branch":
			if is_up(key):
				host.set_header_focus("repo")
			elif is_down(key):
				host.set_header_focus("actions" if _show_actions_row(host) else "changes")
			elif is_enter(key):
				if host.active_tab == "tasks" and host.page_context is not None:
					host.tasks.sync_with_default_remote(host.page_context.repo)
					return ContextDispatch()
				if host.active_tab == "worktrees":
					return ContextDispatch(
						page_result=PageResult(action=PageAction.PUSH, next_page=worktree_add_page()),
					)
				return ContextDispatch(
					page_result=PageResult(action=PageAction.PUSH, next_page=branch_picker_page()),
				)
			return ContextDispatch()

		if host.header_focus == "actions":
			if is_up(key):
				host.set_header_focus("branch")
			elif is_down(key):
				host.set_header_focus("changes")
			elif is_enter(key) and host.has_actions:
				return ContextDispatch(page_result=PageResult(action=PageAction.PUSH, next_page=actions_page()))
			return ContextDispatch()

		if is_up(key) and _content_list_is_at_top(host):
			host.set_header_focus("actions" if _show_actions_row(host) else "branch")
			return ContextDispatch()

		ctx = host.page_context
		if ctx is None:
			return ContextDispatch()
		if host.active_tab == "log":
			host.log.handle_nav_key(key, ctx.repo)
			return ContextDispatch()
		if host.active_tab == "tasks":
			page_result = host.tasks.handle_nav_key(key, ctx.repo)
			return ContextDispatch(page_result=page_result)
		if host.active_tab == "worktrees":
			page_result = host.worktrees.handle_nav_key(key, ctx.repo)
			return ContextDispatch(page_result=page_result)
		nav_result = host.changes.handle_nav_key(key, ctx.repo)
		if nav_result.enter_input:
			return ContextDispatch(next_mode="input")
		return ContextDispatch()


class InputContext:
	def status_hint(self, host: PageInputHost) -> str:
		del host
		return "Esc relinquish input — Enter commit"

	def dispatch_key(self, host: PageInputHost, key: KeyLike) -> ContextDispatch:
		if is_esc(key):
			return ContextDispatch(next_mode="nav")
		ctx = host.page_context
		if ctx is not None:
			result = host.changes.handle_input_key(key, ctx.repo)
			if result.relinquish:
				return ContextDispatch(next_mode="nav")
		return ContextDispatch()


InputMode = NavContext | InputContext


def nav_context() -> NavContext:
	return NavContext()


def input_context() -> InputContext:
	return InputContext()


def _show_actions_row(host: PageInputHost) -> bool:
	return host.active_tab == "status"


def _content_list_is_at_top(host: PageInputHost) -> bool:
	if host.active_tab == "log":
		return host.log.is_at_top()
	if host.active_tab == "tasks":
		return host.tasks.is_at_top()
	if host.active_tab == "worktrees":
		return host.worktrees.is_at_top()
	return host.changes.is_at_top()


def _try_switch_tab(host: PageInputHost, key: KeyLike) -> bool:
	tabs: tuple[_HomeTab, ...] = ("status", "log", "tasks", "worktrees")
	current = host.active_tab
	index = tabs.index(current)
	if is_left(key):
		if index > 0:
			host.set_active_tab(tabs[index - 1])
		return True
	if is_right(key):
		if index < len(tabs) - 1:
			host.set_active_tab(tabs[index + 1])
		return True
	return False