use color_eyre::Result;
use crossterm::event::{KeyCode, KeyEvent, KeyEventKind};
use ratatui::{
    layout::{Alignment, Constraint, Flex, Layout, Position, Rect},
    prelude::Margin,
    style::{Color, Style},
    widgets::{
        Block, BorderType, Cell, Clear, Paragraph, Row, Scrollbar, ScrollbarOrientation,
        ScrollbarState, Table, TableState,
    },
    Frame,
};
use std::sync::mpsc::Sender;
use tokio::sync::mpsc::UnboundedSender;

use super::{Component, CurrentTab, PartialComponent};
use crate::{
    action::Action,
    config::Config,
    palette::StylePalette,
    widgets::{Input, InputRequest},
};

#[derive(Debug, Default, Eq, PartialEq)]
enum Selected {
    #[default]
    Input,
    DefaultRpcs,
    StoredRpcs,
}

#[derive(Debug, Default)]
pub struct GatekeeperEndpoints {
    is_active: bool,
    selected: Selected,
    chain_id: u64,
    rpc_input: Input,
    action_tx: Option<UnboundedSender<Action>>,
    network_tx: Option<Sender<Action>>,
    default_endpoints: Vec<String>,
    stored_endpoints: Vec<String>,
    default_scroll_state: ScrollbarState,
    default_table_state: TableState,
    stored_scroll_state: ScrollbarState,
    stored_table_state: TableState,
    palette: StylePalette,
}

impl GatekeeperEndpoints {
    fn close_popup(&mut self) {
        self.is_active = false;
        if let Some(action_tx) = &self.action_tx {
            let _ = action_tx.send(Action::ClosePopup);
        }
    }

    fn set_chain_id(&mut self, chain_id: u64) {
        self.chain_id = chain_id;
        if let Some(network_tx) = &self.network_tx {
            let _ = network_tx.send(Action::GetRpcEndpoints(chain_id));
        }
    }

    fn submit_message(&mut self) {
        if let Some(network_tx) = &self.network_tx {
            if self.selected == Selected::Input {
                let mut stored_endpoints = self.stored_endpoints.clone();
                stored_endpoints.push(self.rpc_input.value().to_string());
                let _ = network_tx.send(Action::UpdateStoredRpcEndpoints(
                    self.chain_id,
                    stored_endpoints,
                ));
                self.rpc_input = Input::new(String::new());
            }
        }
    }

    fn enter_char(&mut self, new_char: char) {
        match self.selected {
            Selected::Input => {
                let _ = self.rpc_input.handle(InputRequest::InsertChar(new_char));
            }
            Selected::StoredRpcs if (new_char == 'd' || new_char == 'D') => {
                if let Some(index) = self.stored_table_state.selected() {
                    let mut stored_endpoints = self.stored_endpoints.clone();
                    if let Some(network_tx) = &self.network_tx {
                        stored_endpoints.remove(index);
                        let _ = network_tx.send(Action::UpdateStoredRpcEndpoints(
                            self.chain_id,
                            stored_endpoints,
                        ));
                    }
                }
            }
            _ => match new_char {
                'j' => self.move_cursor_down(),
                'k' => self.move_cursor_up(),
                'l' => self.move_cursor_right(),
                'h' => self.move_cursor_left(),
                _ => {}
            },
        }
    }

    fn delete_char(&mut self) {
        if self.selected == Selected::Input {
            let _ = self.rpc_input.handle(InputRequest::DeletePrevChar);
        }
    }

    fn move_cursor_up(&mut self) {
        match self.selected {
            Selected::Input => {}
            Selected::DefaultRpcs => {
                let i = match self.default_table_state.selected() {
                    Some(i) => {
                        if i == 0 {
                            0
                        } else {
                            i - 1
                        }
                    }
                    None => 0,
                };
                self.default_table_state.select(Some(i));
                self.default_scroll_state = self.default_scroll_state.position(i);
            }
            Selected::StoredRpcs => {
                let i = match self.stored_table_state.selected() {
                    Some(i) => {
                        if i == 0 {
                            0
                        } else {
                            i - 1
                        }
                    }
                    None => 0,
                };
                self.stored_table_state.select(Some(i));
                self.stored_scroll_state = self.stored_scroll_state.position(i);
            }
        };
    }

    fn move_cursor_down(&mut self) {
        match self.selected {
            Selected::Input => {}
            Selected::DefaultRpcs => {
                let i = match self.default_table_state.selected() {
                    Some(i) => {
                        if i >= self.default_endpoints.len() - 1 {
                            i
                        } else {
                            i + 1
                        }
                    }
                    None => 0,
                };
                self.default_table_state.select(Some(i));
                self.default_scroll_state = self.default_scroll_state.position(i);
            }
            Selected::StoredRpcs => {
                let i = match self.stored_table_state.selected() {
                    Some(i) => {
                        if i >= self.stored_endpoints.len() - 1 {
                            i
                        } else {
                            i + 1
                        }
                    }
                    None => 0,
                };
                self.stored_table_state.select(Some(i));
                self.stored_scroll_state = self.stored_scroll_state.position(i);
            }
        };
    }

    fn move_cursor_right(&mut self) {
        self.selected = match self.selected {
            Selected::Input => Selected::StoredRpcs,
            Selected::DefaultRpcs => Selected::Input,
            Selected::StoredRpcs => Selected::StoredRpcs,
        };
        self.update_selected_state();
    }

    fn move_cursor_left(&mut self) {
        self.selected = match self.selected {
            Selected::Input => Selected::DefaultRpcs,
            Selected::StoredRpcs => Selected::Input,
            Selected::DefaultRpcs => Selected::DefaultRpcs,
        };
        self.update_selected_state();
    }

    fn update_selected_state(&mut self) {
        self.stored_table_state.select(None);
        self.default_table_state.select(None);
        self.stored_scroll_state = self.stored_scroll_state.position(0);
        self.default_scroll_state = self.default_scroll_state.position(0);
    }

    fn prepare_table<'a>(
        &self,
        rpcs: &'a Vec<String>,
        title_name: &'a str,
        border_style: Color,
        border_type: BorderType,
        scrollbar_style: Style,
    ) -> (Table<'a>, Scrollbar<'a>) {
        let table = Table::new(
            rpcs.iter()
                .map(|endpoint| Row::new(vec![Cell::from(endpoint.as_str())]))
                .collect::<Vec<Row>>(),
            [Constraint::Min(1)],
        )
        .highlight_style(self.palette.create_highlight_style())
        .block(
            Block::bordered()
                .border_style(border_style)
                .border_type(border_type)
                .title_alignment(Alignment::Right)
                .title_style(self.palette.create_title_style(false))
                .title(title_name),
        );

        let scrollbar = Scrollbar::default()
            .orientation(ScrollbarOrientation::VerticalRight)
            .begin_symbol(None)
            .end_symbol(None)
            .style(scrollbar_style);

        (table, scrollbar)
    }
}

impl PartialComponent for GatekeeperEndpoints {
    fn set_active(&mut self, current_tab: CurrentTab) {
        match current_tab {
            CurrentTab::GatekeeperEndpoints => self.is_active = true,
            _ => {
                self.is_active = false;
                self.rpc_input = Input::new(String::new());
            }
        };
    }
}

impl Component for GatekeeperEndpoints {
    fn register_network_handler(&mut self, tx: Sender<Action>) -> Result<()> {
        self.network_tx = Some(tx);
        Ok(())
    }

    fn register_action_handler(&mut self, tx: UnboundedSender<Action>) -> Result<()> {
        self.action_tx = Some(tx);
        Ok(())
    }

    fn register_config_handler(&mut self, config: Config) -> Result<()> {
        if let Some(style) = config.styles.get(&crate::app::Mode::Wallet) {
            self.palette
                .with_normal_style(style.get("normal_style").copied());
            self.palette
                .with_normal_border_style(style.get("normal_border_style").copied());
            self.palette
                .with_normal_title_style(style.get("normal_title_style").copied());
            self.palette
                .with_popup_style(style.get("popup_style").copied());
            self.palette
                .with_popup_title_style(style.get("popup_title_style").copied());
            self.palette
                .with_hover_style(style.get("hover_style").copied());
            self.palette
                .with_hover_border_style(style.get("hover_border_style").copied());
            self.palette
                .with_hover_title_style(style.get("hover_title_style").copied());
            self.palette
                .with_highlight_style(style.get("highlight_style").copied());
            self.palette
                .with_scrollbar_style(style.get("scrollbar_style").copied());
        }
        Ok(())
    }

    fn handle_key_event(&mut self, key: KeyEvent) -> Result<Option<Action>> {
        if self.is_active && key.kind == KeyEventKind::Press {
            match key.code {
                KeyCode::Enter => self.submit_message(),
                KeyCode::Char(to_insert) => self.enter_char(to_insert),
                KeyCode::Backspace => self.delete_char(),
                KeyCode::Left => self.move_cursor_left(),
                KeyCode::Right => self.move_cursor_right(),
                KeyCode::Up => self.move_cursor_up(),
                KeyCode::Down => self.move_cursor_down(),
                KeyCode::Esc => self.close_popup(),
                _ => {}
            };
        }
        Ok(None)
    }

    fn update(&mut self, action: Action) -> Result<Option<Action>> {
        match action {
            Action::SetChoosenGatekeeper(chain_id) => self.set_chain_id(chain_id),
            Action::SetGatekeepedNetwork(network) => {
                self.default_endpoints = network.default_endpoints
            }
            Action::SetStoredRpcEndpoints(stored_endpoints) => {
                self.stored_endpoints = stored_endpoints
            }
            _ => {}
        };
        Ok(None)
    }

    fn draw(&mut self, frame: &mut Frame, area: Rect) -> Result<()> {
        if self.is_active {
            let (border_style, border_type) = self.palette.create_popup_style();
            let (selected_border_style, selected_border_type) =
                self.palette.create_border_style(true);
            let scrollbar_style = self.palette.create_scrollbar_style();

            let (default_border_style, default_border_type) = match self.selected {
                Selected::DefaultRpcs => (selected_border_style, selected_border_type),
                _ => (border_style, border_type),
            };

            let (stored_border_style, stored_border_type) = match self.selected {
                Selected::StoredRpcs => (selected_border_style, selected_border_type),
                _ => (border_style, border_type),
            };

            let (input_border_style, input_border_type) = match self.selected {
                Selected::Input => (selected_border_style, selected_border_type),
                _ => (border_style, border_type),
            };

            let (default_rpcs, default_scrollbar) = self.prepare_table(
                &self.default_endpoints,
                "Default RPCs",
                default_border_style,
                default_border_type,
                scrollbar_style,
            );
            let (stored_rpcs, stored_scrollbar) = self.prepare_table(
                &self.stored_endpoints,
                "Stored RPCs",
                stored_border_style,
                stored_border_type,
                scrollbar_style,
            );

            let input = Paragraph::new(self.rpc_input.value()).block(
                Block::bordered()
                    .border_style(input_border_style)
                    .border_type(input_border_type)
                    .title_style(self.palette.create_popup_title_style())
                    .title_alignment(Alignment::Right)
                    .title("Input new RPC"),
            );

            let v = Layout::vertical([Constraint::Max(14)]).flex(Flex::Center);
            let h = Layout::horizontal([Constraint::Max(80)]).flex(Flex::Center);
            let [area] = v.areas(area);
            let [area] = h.areas(area);
            frame.render_widget(Clear, area);

            let [tables_area, input_area] =
                Layout::vertical([Constraint::Length(11), Constraint::Length(3)]).areas(area);

            let [default_table_area, stored_table_area] =
                Layout::horizontal([Constraint::Max(40), Constraint::Max(40)]).areas(tables_area);

            frame.render_stateful_widget(
                default_rpcs,
                default_table_area,
                &mut self.default_table_state,
            );
            frame.render_stateful_widget(
                default_scrollbar,
                default_table_area.inner(Margin {
                    vertical: 1,
                    horizontal: 1,
                }),
                &mut self.default_scroll_state,
            );

            frame.render_stateful_widget(
                stored_rpcs,
                stored_table_area,
                &mut self.stored_table_state,
            );
            frame.render_stateful_widget(
                stored_scrollbar,
                stored_table_area.inner(Margin {
                    vertical: 1,
                    horizontal: 1,
                }),
                &mut self.stored_scroll_state,
            );

            frame.render_widget(input, input_area);
            frame.set_cursor_position(Position::new(
                input_area.x + self.rpc_input.cursor() as u16 + 1,
                input_area.y + 1,
            ));
        }
        Ok(())
    }
}