//! `tahuantinsuyu-panel` — control panel inferior de la app.
//!
//! Lee los módulos disponibles para la carta activa (vía
//! [`tahuantinsuyu_modules::Registry::for_kind`]) y pinta sus
//! [`Control`]s como toggles / sliders / selects. Cada cambio emite
//! [`PanelEvent`] que la app traduce a mutaciones de visibilidad sobre
//! el canvas (fase 4) y eventualmente a `ModuleState` en la store.
//!
//! ## Estado interno
//!
//! El panel mantiene un cache `toggle_state` con los valores actuales
//! de los toggles por (module_id, key). Inicializa desde los defaults
//! declarados por el módulo y se actualiza con cada click. Los sliders
//! / selects todavía no son interactivos en fase 4 — quedan como
//! display de "valor default".

#![forbid(unsafe_code)]
#![warn(rust_2018_idioms)]

use std::collections::HashMap;

use gpui::{
    ClickEvent, Context, EventEmitter, IntoElement, ParentElement, Render, SharedString, Styled,
    Window, div, prelude::*, px,
};

use tahuantinsuyu_model::ChartKind;
use tahuantinsuyu_modules::{Control, Module, Registry};
use yahweh_theme::Theme;

// =====================================================================
// Eventos
// =====================================================================

#[derive(Clone, Debug)]
pub enum PanelEvent {
    ModuleToggled { module_id: String, enabled: bool },
    ControlChanged {
        module_id: String,
        key: String,
        value: serde_json::Value,
    },
}

// =====================================================================
// Widget
// =====================================================================

pub struct ControlPanel {
    active_kind: Option<ChartKind>,
    /// Cache de toggles por (module_id, key). Se popula lazy desde los
    /// defaults la primera vez que se renderea un kind.
    toggle_state: HashMap<(String, String), bool>,
    registry: Registry,
}

impl EventEmitter<PanelEvent> for ControlPanel {}

impl ControlPanel {
    pub fn new(cx: &mut Context<Self>) -> Self {
        cx.observe_global::<Theme>(|_, cx| cx.notify()).detach();
        Self {
            active_kind: None,
            toggle_state: HashMap::new(),
            registry: Registry::with_builtins(),
        }
    }

    pub fn set_active_kind(&mut self, kind: Option<ChartKind>, cx: &mut Context<Self>) {
        // Si cambia el kind, inicializamos defaults para sus módulos.
        if self.active_kind != kind {
            if let Some(k) = kind {
                for m in self.registry.for_kind(k) {
                    for c in m.controls() {
                        if let Control::Toggle { key, default, .. } = c {
                            self.toggle_state
                                .entry((m.id().to_string(), key))
                                .or_insert(default);
                        }
                    }
                }
            }
        }
        self.active_kind = kind;
        cx.notify();
    }

    /// Setea un toggle desde afuera (sin emitir evento). Útil cuando el
    /// canvas se autotoggleó via hotkey y queremos sincronizar el panel.
    pub fn set_toggle(&mut self, module_id: &str, key: &str, value: bool, cx: &mut Context<Self>) {
        self.toggle_state
            .insert((module_id.to_string(), key.to_string()), value);
        cx.notify();
    }

    fn on_toggle_click(&mut self, module_id: String, key: String, cx: &mut Context<Self>) {
        let entry = self
            .toggle_state
            .entry((module_id.clone(), key.clone()))
            .or_insert(true);
        *entry = !*entry;
        let new_val = *entry;
        cx.emit(PanelEvent::ControlChanged {
            module_id,
            key,
            value: serde_json::Value::Bool(new_val),
        });
        cx.notify();
    }
}

impl Render for ControlPanel {
    fn render(&mut self, _w: &mut Window, cx: &mut Context<Self>) -> impl IntoElement {
        let theme = Theme::global(cx).clone();
        // Snapshot de los módulos a renderear — borrowing isssues si
        // dejáramos el iterador vivo mientras mutamos en el closure.
        let modules: Vec<(String, String, String, Vec<Control>)> = match self.active_kind {
            Some(k) => self
                .registry
                .for_kind(k)
                .iter()
                .map(|m| {
                    (
                        m.id().to_string(),
                        m.label().to_string(),
                        m.description().to_string(),
                        m.controls(),
                    )
                })
                .collect(),
            None => Vec::new(),
        };

        let header = div()
            .h(px(28.0))
            .px(px(12.0))
            .flex()
            .flex_row()
            .items_center()
            .gap(px(8.0))
            .border_b_1()
            .border_color(theme.border)
            .child(
                div()
                    .text_size(px(11.0))
                    .text_color(theme.fg_muted)
                    .child("Panel de control"),
            )
            .child(
                div()
                    .ml_auto()
                    .text_size(px(10.0))
                    .text_color(theme.fg_disabled)
                    .child(match self.active_kind {
                        Some(k) => SharedString::from(format!("{:?}", k)),
                        None => SharedString::from("sin carta activa"),
                    }),
            );

        let mut body = div()
            .flex()
            .flex_row()
            .flex_wrap()
            .gap(px(16.0))
            .px(px(12.0))
            .py(px(8.0));

        if modules.is_empty() {
            body = body.child(
                div()
                    .text_size(px(11.0))
                    .text_color(theme.fg_disabled)
                    .child("Seleccioná una carta para ver sus controles."),
            );
        } else {
            for (id, label, desc, controls) in &modules {
                body = body.child(self.render_module(&theme, id, label, desc, controls, cx));
            }
        }

        div()
            .size_full()
            .bg(theme.bg_panel.clone())
            .flex()
            .flex_col()
            .child(header)
            .child(body)
    }
}

impl ControlPanel {
    fn render_module(
        &self,
        theme: &Theme,
        module_id: &str,
        label: &str,
        description: &str,
        controls: &[Control],
        cx: &mut Context<Self>,
    ) -> gpui::Div {
        let header = div()
            .flex()
            .flex_col()
            .gap(px(2.0))
            .child(
                div()
                    .text_size(px(12.0))
                    .text_color(theme.fg_text)
                    .child(SharedString::from(label.to_string())),
            )
            .child(
                div()
                    .text_size(px(10.0))
                    .text_color(theme.fg_muted)
                    .child(SharedString::from(description.to_string())),
            );

        let mut body = div().flex().flex_col().gap(px(4.0));
        for c in controls {
            body = body.child(self.render_control(theme, module_id, c, cx));
        }

        div()
            .min_w(px(240.0))
            .p(px(8.0))
            .rounded(px(6.0))
            .bg(theme.bg_panel_alt.clone())
            .border_1()
            .border_color(theme.border)
            .flex()
            .flex_col()
            .gap(px(6.0))
            .child(header)
            .child(body)
    }

    fn render_control(
        &self,
        theme: &Theme,
        module_id: &str,
        c: &Control,
        cx: &mut Context<Self>,
    ) -> gpui::Div {
        match c {
            Control::Toggle {
                key,
                label,
                default,
                hotkey,
            } => {
                let active = self
                    .toggle_state
                    .get(&(module_id.to_string(), key.clone()))
                    .copied()
                    .unwrap_or(*default);
                let dot_color = if active {
                    theme.accent
                } else {
                    theme.fg_disabled
                };
                let id_str: SharedString =
                    SharedString::from(format!("tts-toggle-{}-{}", module_id, key));
                let id_for_listener = (module_id.to_string(), key.clone());
                let row = div()
                    .id(gpui::ElementId::from(id_str))
                    .flex()
                    .flex_row()
                    .items_center()
                    .gap(px(8.0))
                    .px(px(6.0))
                    .py(px(3.0))
                    .rounded(px(4.0))
                    .hover(|s| s.bg(theme.bg_row_hover))
                    .child(div().size(px(8.0)).rounded(px(4.0)).bg(dot_color))
                    .child(
                        div()
                            .text_size(px(11.0))
                            .text_color(theme.fg_text)
                            .child(SharedString::from(label.clone())),
                    )
                    .child(
                        div()
                            .ml_auto()
                            .text_size(px(10.0))
                            .text_color(theme.fg_muted)
                            .child(SharedString::from(
                                hotkey
                                    .clone()
                                    .map(|h| format!("[{}]", h))
                                    .unwrap_or_default(),
                            )),
                    )
                    .on_click(cx.listener(move |this, _: &ClickEvent, _, cx| {
                        let (m, k) = id_for_listener.clone();
                        this.on_toggle_click(m, k, cx);
                    }));
                // `id()` devuelve `Stateful<Div>`; envolvemos para
                // mantener uniforme el return type del match.
                div().child(row)
            }
            Control::Slider {
                label,
                min,
                max,
                default,
                ..
            } => div()
                .flex()
                .flex_row()
                .items_center()
                .gap(px(8.0))
                .px(px(6.0))
                .py(px(3.0))
                .child(
                    div()
                        .text_size(px(11.0))
                        .text_color(theme.fg_text)
                        .child(SharedString::from(label.clone())),
                )
                .child(
                    div()
                        .ml_auto()
                        .text_size(px(10.0))
                        .text_color(theme.fg_muted)
                        .child(SharedString::from(format!("{} ({}…{})", default, min, max))),
                ),
            Control::Select { label, default, .. } => div()
                .flex()
                .flex_row()
                .items_center()
                .gap(px(8.0))
                .px(px(6.0))
                .py(px(3.0))
                .child(
                    div()
                        .text_size(px(11.0))
                        .text_color(theme.fg_text)
                        .child(SharedString::from(label.clone())),
                )
                .child(
                    div()
                        .ml_auto()
                        .text_size(px(10.0))
                        .text_color(theme.fg_muted)
                        .child(SharedString::from(default.clone())),
                ),
            Control::TextInput { label, default, .. } => div()
                .flex()
                .flex_row()
                .items_center()
                .gap(px(8.0))
                .px(px(6.0))
                .py(px(3.0))
                .child(
                    div()
                        .text_size(px(11.0))
                        .text_color(theme.fg_text)
                        .child(SharedString::from(label.clone())),
                )
                .child(
                    div()
                        .ml_auto()
                        .text_size(px(10.0))
                        .text_color(theme.fg_muted)
                        .child(SharedString::from(default.clone())),
                ),
        }
    }
}