use crate::data_provider::card_sets::{delete_set, update_card_set};
use crate::data_provider::card_stats::load_stats_of_set;
use crate::history::HistoryState;
use crate::lang::{SetOrderMode, WordData};
use crate::navigation::Page::{History, PreviousPage, Repetition, RepetitionSettings};
use crate::navigation::{NavigatedPage, Page};
use crate::repetition::RepetitionState;
use crate::repetition_settings::RepetitionSettingsState;
use crate::repetitions::RepetitionsMessage::*;
use crate::styling::*;
use crate::{AppState, RootMessage};
use chrono::{Days, Local};
use iced::widget::button::{danger, Status};
pub use iced::widget::button::{Catalog, Style};
use iced::widget::container::bordered_box;
use iced::widget::tooltip::Position::Top;
use iced::widget::{
    button, column, container, radio, row, scrollable, space, svg, text, text_input, tooltip, Column,
    Row,
};
use iced::{Background, Border, Center, Color, Element, Fill, Length, Shadow, Task, Theme};
use iced_core::border::Radius;
use iced_core::svg::Handle;
use iced_core::Padding;
use rhai::{Engine, Scope};
use std::sync::{Arc, Mutex};

#[derive(Clone)]
pub struct RepetitionsState {
    selected_set: Option<usize>,
    correct_filters: Vec<bool>,
    pub state: Arc<Mutex<AppState>>,
}

impl NavigatedPage<RepetitionsMessage> for RepetitionsState {
    fn navigate(&self, message: &RepetitionsMessage) -> Option<Page> {
        if let Back = message {
            Some(PreviousPage)
        } else if let GoToHistory = message {
            let card_set;
            {
                card_set = self.state.lock().unwrap().card_sets[self.selected_set.unwrap()].id;
            }
            Some(History(HistoryState::new(card_set, self.state.clone())))
        } else if let GoToRepetition = message {
            let clone = self.state.clone();
            let card_set;
            {
                card_set = self.state.lock().unwrap().card_sets[self.selected_set.unwrap()].clone();
            }
            Some(Repetition(RepetitionState::new(card_set, clone)))
        } else if let GoToSettings = message {
            Some(RepetitionSettings(RepetitionSettingsState::new(
                self.selected_set.unwrap(),
                self.state.clone(),
            )))
        } else {
            None
        }
    }
}

impl RepetitionsState {
    pub(crate) fn new(state: Arc<Mutex<AppState>>) -> RepetitionsState {
        let count = state.lock().unwrap().card_sets.len();
        RepetitionsState {
            selected_set: None,
            correct_filters: vec![true; count],
            state,
        }
    }
}

impl RepetitionsState {
    pub fn update(&mut self, message: RepetitionsMessage) -> Task<RootMessage> {
        let mut state = self.state.lock().unwrap();
        match message {
            Next => {}
            Back => {}
            GoToRepetition => {}
            GoToHistory => {}
            GoToSettings => {}
            CreateSet => {
                let index = state.card_sets.len() + 1;
                state
                    .card_sets
                    .push(CardSetSettings::with_name(format!("Card set #{}", index)));
                self.correct_filters.push(true);
            }
            DeleteSet => {
                let set = state.card_sets.remove(self.selected_set.unwrap());
                self.correct_filters.remove(self.selected_set.unwrap());
                self.selected_set = None;
                delete_set(&set, &state.connection);
            }
            SelectSet(index) => {
                self.selected_set = Some(index);
                let mut set = state.card_sets.get(index).unwrap().clone();
                set.update_worst_words(&state);
                state.card_sets[index] = set;
            }
            SetName(new) => {
                state.card_sets[self.selected_set.unwrap()].name = new;
            }
            Save => {
                for i in 0..state.card_sets.len() {
                    self.correct_filters[i] = state.card_sets[i].check_filter();
                }

                let set = &mut state.card_sets[self.selected_set.unwrap()].clone();

                update_card_set(set, &state.connection);

                state.card_sets[self.selected_set.unwrap()] = set.clone();
            }
            SetForward(new) => {
                state.card_sets[self.selected_set.unwrap()].forward = new;
            }
            SetBackward(new) => {
                state.card_sets[self.selected_set.unwrap()].backward = new;
            }
            SetFilter(new) => {
                state.card_sets[self.selected_set.unwrap()].filter = new;
            }
            TryFilter => {
                let set = state.card_sets.get(self.selected_set.unwrap()).unwrap();
                let count = set.get_word_list(&state).len();
                state.card_sets[self.selected_set.unwrap()].count = Some(count);
            }
            SetOpenMode(mode) => {
                state
                    .card_sets
                    .get_mut(self.selected_set.unwrap())
                    .unwrap()
                    .open_mode = mode;
            }
        }
        Task::none()
    }

    pub fn view(&self) -> Element<'_, RepetitionsMessage> {
        back_overlay(
            row![
                column![
                    scrollable(self.sets_list()).height(Fill),
                    button("Добавить")
                        .style(jl_button)
                        .width(Fill)
                        .on_press(CreateSet),
                ]
                .spacing(DEFAULT_SPACING)
                .width(Length::FillPortion(1)),
                self.selected_set_view(),
            ]
            .align_y(Center)
            .spacing(DEFAULT_SPACING)
            .width(Fill)
            .height(Fill)
            .into(),
            Back,
        )
    }

    fn launch_delete_button(&self, set: &CardSetSettings) -> Element<'_, RepetitionsMessage> {
        if set.id != 0 {
            return row![
                space().width(Fill),
                button(text!("Начать повторение").width(200).center())
                    .style(cta_button)
                    .on_press(GoToRepetition)
            ]
            .into();
        }
        button("Удалить").style(danger).on_press(DeleteSet).into()
    }

    fn selected_set_view(&self) -> Element<'_, RepetitionsMessage> {
        if let Some(index) = self.selected_set {
            let set;
            {
                let state = self.state.lock().unwrap();
                if state.card_sets.len() <= index {
                    return space().width(Length::FillPortion(3)).into();
                }
                set = state.card_sets[index].clone();
            }
            return column![
                scrollable(
                    column![
                        column![
                            text!("Название набора"),
                            row![
                                text_input("", &set.name).on_input(SetName),
                                button(svg(Handle::from_memory(SETTINGS_ICON)))
                                    .width(43)
                                    .on_press(GoToSettings),
                            ]
                            .spacing(HALF_SPACING)
                        ]
                        .spacing(QUARTER_SPACING),
                        {
                            if set.id == 0 {
                                column![
                                    column![
                                        text!("Передняя сторона"),
                                        text_input("", &set.forward).on_input(SetForward),
                                    ]
                                    .spacing(QUARTER_SPACING),
                                    column![
                                        text!("Задняя сторона"),
                                        text_input("", &set.backward).on_input(SetBackward),
                                    ]
                                    .spacing(QUARTER_SPACING),
                                    column![
                                        text!("Фильтр"),
                                        text_input("", &set.filter).on_input(SetFilter),
                                        button("Проверить фильтр")
                                            .style(jl_button)
                                            .on_press(TryFilter),
                                        self.count_view(&set),
                                    ]
                                    .spacing(QUARTER_SPACING),
                                ]
                                .spacing(DEFAULT_SPACING)
                            } else {
                                self.filled_set_data_view(&set)
                            }
                        },
                        radio(
                            "Обычный режим",
                            SetOrderMode::Default,
                            Some(set.open_mode),
                            SetOpenMode
                        ),
                        self.words_words_view(&set),
                        button("История").style(jl_button).on_press(GoToHistory),
                    ]
                    .spacing(DEFAULT_SPACING)
                    .padding(Padding {
                        top: 0.0,
                        right: DEFAULT_SPACING,
                        bottom: 0.0,
                        left: 0.0,
                    })
                )
                .height(Fill),
                row![
                    button("Сохранить").style(jl_button).on_press(Save),
                    self.launch_delete_button(&set)
                ]
                .spacing(DEFAULT_SPACING),
            ]
            .spacing(DEFAULT_SPACING)
            .width(Length::FillPortion(3))
            .into();
        }
        space().width(Length::FillPortion(3)).into()
    }

    fn filled_set_data_view(&self, set: &CardSetSettings) -> Column<'_, RepetitionsMessage> {
        column![self.activity_bar(set)].align_x(Center)
            .width(Fill)
            .spacing(DEFAULT_SPACING)
            .into()
    }

    fn activity_bar(&self, set: &CardSetSettings) -> Element<'_, RepetitionsMessage> {
        let state = self.state.lock().unwrap();
        let history = state.activity.get(&set.id);
        let mut counts: Vec<u32> = vec![0; 30 * 7];

        let now = Local::now().date_naive();

        if let Some(history) = history {
            for (date, activity) in history {
                let distance = *date - now;
                let index = counts.len() as i64 - distance.num_days() - 1;

                if index < 0 {
                    continue;
                }

                counts[index as usize] = *activity;
            }
        }

        let mut row = Row::new()
            .padding(Padding {
                top: 0.0,
                right: 0.0,
                bottom: 0.0,
                left: DEFAULT_SPACING,
            })
            .spacing(QUARTER_SPACING);

        const MAX_DAY_COUNT: f32 = 128.0;

        let mut iter = counts.into_iter();
        for i in 0..30 {
            let mut column = Column::new().spacing(QUARTER_SPACING);

            for j in 0..7 {
                let value = iter.next().unwrap() as f32;
                let k = (value / MAX_DAY_COUNT).min(1.0) * 0.9 + 0.1;

                let date = now.clone().checked_sub_days(Days::new(30 * 7 - i * 7 - j - 1)).unwrap();

                column = column.push(tooltip(
                    iced::widget::container(space().height(15).width(15)).style(
                        move |x: &Theme| container::Style {
                            text_color: None,
                            background: Some(Background::Color(x.palette().primary.scale_alpha(k))),
                            border: Border {
                                color: Default::default(),
                                width: 0.0,
                                radius: Radius::new(5),
                            },
                            shadow: Default::default(),
                            snap: false,
                        },
                    ),
                    text!("{} {} карточки", date.format("%Y.%m.%d"), value),
                    Top,
                ));
            }

            row = row.push(column);
        }
        scrollable(column!["Карта активности", row].spacing(QUARTER_SPACING).align_x(Center)).into()
    }

    fn words_words_view(&self, set: &CardSetSettings) -> Element<'_, RepetitionsMessage> {
        column![
            text!("Худшие слова"),
            container(scrollable(self.worst_words_list(&set)).height(200)).style(bordered_box),
            radio(
                "Начать с плохих слов",
                SetOrderMode::TrainWorstFirst,
                Some(set.open_mode),
                SetOpenMode
            ),
            radio(
                "Полностью случайно",
                SetOrderMode::FullRandom,
                Some(set.open_mode),
                SetOpenMode
            )
        ]
        .spacing(DEFAULT_SPACING)
        .into()
    }

    fn worst_words_list(&self, set: &CardSetSettings) -> Element<'_, RepetitionsMessage> {
        let mut column = Column::new();

        for word in set.worst_words_list.clone().unwrap() {
            column = column.push(text!("{} | {}", &word.key, &word.value));
        }
        column.into()
    }

    fn count_view(&self, set: &CardSetSettings) -> Element<'_, RepetitionsMessage> {
        if let Some(count) = set.count {
            return text!("Количество слов: {}", count).into();
        }
        space().into()
    }

    fn sets_list(&self) -> Column<'_, RepetitionsMessage> {
        let mut column = Column::new();
        let mut i = 0;
        let sets = &self.state.lock().unwrap().card_sets;
        for set in sets {
            column = column.push(
                button(text!("{}", set.name.clone()))
                    .on_press_with(move || SelectSet(i.clone()))
                    .style(move |_x: &Theme, status: Status| Style {
                        background: if status == Status::Hovered {
                            Some(Background::Color(Color::WHITE.scale_alpha(0.2)))
                        } else {
                            None
                        },
                        text_color: if self.correct_filters[i.clone()] {
                            _x.palette().primary
                        } else {
                            _x.palette().warning
                        },
                        border: Border {
                            color: Default::default(),
                            width: 0.0,
                            radius: BUTTON_RADIUS.into(),
                        },
                        shadow: Shadow::default(),
                        snap: false,
                    }),
            );
            i += 1;
        }

        column
    }
}

#[derive(Clone)]
pub enum RepetitionsMessage {
    Next,
    Back,
    GoToRepetition,
    CreateSet,
    DeleteSet,
    SetName(String),
    SelectSet(usize),
    Save,
    SetForward(String),
    SetBackward(String),
    SetFilter(String),
    TryFilter,
    SetOpenMode(SetOrderMode),
    GoToHistory,
    GoToSettings,
}

#[derive(Clone)]
pub struct CardSetSettings {
    pub id: u32,
    pub name: String,
    pub forward: String,
    pub backward: String,
    pub filter: String,
    pub count: Option<usize>,
    pub worst_words_list: Option<Vec<WordData>>,
    pub open_mode: SetOrderMode,
}

impl CardSetSettings {
    fn with_name(name: String) -> CardSetSettings {
        CardSetSettings {
            id: 0,
            name,
            forward: "".to_string(),
            backward: "".to_string(),
            filter: "true".to_string(),
            count: None,
            worst_words_list: None,
            open_mode: SetOrderMode::Default,
        }
    }

    fn check_filter(&self) -> bool {
        let engine = Engine::new();
        let ast = engine.compile(&self.filter);
        ast.is_ok()
    }

    pub fn get_word_list(&self, state: &AppState) -> Vec<WordData> {
        let mut list = vec![];
        let engine = Engine::new();
        let ast = engine.compile(&self.filter);
        if ast.is_err() {
            return list;
        }

        let ast = ast.unwrap();

        let groups = &state.word_groups;

        for word in &state.dictionary {
            let mut more = rhai::Map::new();
            for iced in &word.additional {
                more.insert(iced.0.clone().into(), iced.1.clone().into());
            }
            let mut scope = Scope::new();
            scope
                .push_constant("key", word.key.clone())
                .push_constant("value", word.value.clone())
                .push_constant("tags", word.tags.clone())
                .push_constant("more", more)
                .push_constant(
                    "group",
                    groups
                        .iter()
                        .find(|g| g.id == word.group_id)
                        .cloned()
                        .unwrap()
                        .name,
                );

            let result = engine.eval_ast_with_scope::<bool>(&mut scope, &ast);
            if result.is_ok() && result.unwrap() {
                list.push(word.clone());
            }
        }

        list
    }

    pub fn require_speech(&self) -> bool {
        self.forward == "speech" || self.backward == "speech"
    }

    fn update_worst_words(&mut self, state: &AppState) {
        if let Some(_) = self.worst_words_list {
            return;
        }

        let connection = &state.connection;
        let mut stats = load_stats_of_set(self, connection);
        stats.sort_by_key(|s| s.calculated_score() as i32);
        let avg = stats.iter().map(|s| s.calculated_score()).sum::<f32>() / stats.len() as f32;
        let avg = avg * 0.7;
        let bad: Vec<WordData> = stats
            .iter()
            .take_while(|word| word.calculated_score() < avg)
            .map(|stat| {
                state.dictionary[state
                    .dictionary
                    .binary_search_by_key(&stat.word_id, |x| x.id)
                    .unwrap()]
                .clone()
            })
            .collect();

        self.worst_words_list = Some(bad.clone());
    }
}