vig 0.9.0

use crate::core::config::Config;
use crate::core::keymap::{build_app_keymap, AppAction, Keymap};
use crate::core::page::PageAction;
pub use crate::core::search::SearchMatch;
use anyhow::{anyhow, Result};
use crossterm::event::KeyEvent;
use std::path::PathBuf;

pub struct ErrorDialogState {
    pub title: String,
    pub message: String,
}

pub struct AppContext {
    pub should_quit: bool,
    pub active_page: usize,
    pub page_labels: Vec<&'static str>,
    /// Display strings of the app-keymap keys that switch to each page
    /// (same index as `page_labels`); derived by [`App::new`] from the
    /// `app { }` block, so a page may have several keys or none.
    pub page_keys: Vec<Vec<String>>,
    pub show_help: bool,
    pub status_message: Option<String>,
    pub error_dialog: Option<ErrorDialogState>,
    pub workdir: PathBuf,
    /// Set when terminal content outside ratatui's buffer (inline images)
    /// must be wiped: the main loop clears the terminal before the next draw.
    pub needs_full_redraw: bool,
}

impl AppContext {
    /// Consume the pending full-redraw request.
    pub fn take_full_redraw(&mut self) -> bool {
        std::mem::take(&mut self.needs_full_redraw)
    }

    pub fn show_error(&mut self, title: &str, message: String) {
        self.error_dialog = Some(ErrorDialogState {
            title: title.to_string(),
            message,
        });
    }

    pub fn open_url(&mut self, url: &str) {
        match crate::core::browser::open_url(url) {
            Ok(()) => self.status_message = Some("Opening in browser...".to_string()),
            Err(e) => self.status_message = Some(e),
        }
    }

    pub fn copy_to_clipboard(&mut self, text: &str) {
        if text.is_empty() {
            return;
        }
        let line_count = text.lines().count().max(1);
        match arboard::Clipboard::new() {
            Ok(mut clip) => {
                if clip.set_text(text).is_ok() {
                    self.status_message = Some(format!(
                        "Yanked {line_count} line{}",
                        if line_count == 1 { "" } else { "s" }
                    ));
                } else {
                    self.status_message = Some("Clipboard error".to_string());
                }
            }
            Err(_) => {
                self.status_message = Some("Clipboard unavailable".to_string());
            }
        }
    }
}

pub trait PageState {
    /// Canonical, stable page identifier used in config (e.g. `"git"`, `"github"`).
    /// This is what `default.kdl`'s `app` block references via `page:<id>` — keep it
    /// distinct from [`label`](Self::label), which is the human-facing display name.
    fn id(&self) -> &'static str;
    fn label(&self) -> &'static str;
    fn help_bindings(&self) -> Vec<(String, String)> {
        vec![]
    }
    fn handle_key(&mut self, ctx: &mut AppContext, key: KeyEvent) -> Result<PageAction>;
    fn render(&mut self, f: &mut ratatui::Frame, ctx: &AppContext, area: ratatui::layout::Rect);
    fn intercepts_all_keys(&self) -> bool {
        false
    }
    fn on_tick(&mut self, _ctx: &mut AppContext) {}
    fn on_fs_change(&mut self, _ctx: &mut AppContext) -> Result<()> {
        Ok(())
    }
    fn on_suspend_return(
        &mut self,
        _ctx: &mut AppContext,
        _status: std::io::Result<std::process::ExitStatus>,
    ) -> Result<()> {
        Ok(())
    }
    fn on_activate(&mut self, _ctx: &mut AppContext) {}
    fn drain_background(&mut self) {}
}

// --- Public Page wrapper ---

pub struct Page(Box<dyn PageState>);

impl Page {
    pub fn new(state: impl PageState + 'static) -> Self {
        Self(Box::new(state))
    }

    pub fn id(&self) -> &'static str {
        self.0.id()
    }

    pub fn label(&self) -> &'static str {
        self.0.label()
    }

    pub fn help_bindings(&self) -> Vec<(String, String)> {
        self.0.help_bindings()
    }

    fn handle_key(&mut self, ctx: &mut AppContext, key: KeyEvent) -> Result<PageAction> {
        self.0.handle_key(ctx, key)
    }

    fn render(&mut self, f: &mut ratatui::Frame, ctx: &AppContext, area: ratatui::layout::Rect) {
        self.0.render(f, ctx, area);
    }

    fn intercepts_all_keys(&self) -> bool {
        self.0.intercepts_all_keys()
    }

    fn on_tick(&mut self, ctx: &mut AppContext) {
        self.0.on_tick(ctx);
    }

    fn on_fs_change(&mut self, ctx: &mut AppContext) -> Result<()> {
        self.0.on_fs_change(ctx)
    }

    fn on_suspend_return(
        &mut self,
        ctx: &mut AppContext,
        status: std::io::Result<std::process::ExitStatus>,
    ) -> Result<()> {
        self.0.on_suspend_return(ctx, status)
    }

    fn on_activate(&mut self, ctx: &mut AppContext) {
        self.0.on_activate(ctx);
    }

    fn drain_background(&mut self) {
        self.0.drain_background();
    }
}

pub struct App {
    pub ctx: AppContext,
    pages: Vec<Page>,
    app_keymap: Keymap<AppAction>,
}

/// Display strings of the keys bound to `SwitchPage(idx)` for every page
/// index below `page_count`, in keymap insertion order.
fn page_keys(app_keymap: &Keymap<AppAction>, page_count: usize) -> Vec<Vec<String>> {
    let mut keys = vec![Vec::new(); page_count];
    for (ki, action) in app_keymap.entries() {
        if let AppAction::SwitchPage(idx) = action {
            if let Some(slot) = keys.get_mut(*idx) {
                slot.push(ki.to_string());
            }
        }
    }
    keys
}

impl App {
    pub fn new(mut ctx: AppContext, pages: Vec<Page>, cfg: &Config) -> Result<Self> {
        let page_names: Vec<&str> = pages.iter().map(|p| p.id()).collect();
        let entries = cfg.app_entries()?;
        let app_keymap = build_app_keymap(&entries, &page_names)
            .map_err(|e| anyhow!("invalid {}: app block: {e}", cfg.describe()))?;
        ctx.page_keys = page_keys(&app_keymap, pages.len());
        Ok(Self {
            ctx,
            pages,
            app_keymap,
        })
    }

    pub fn drain_all_background(&mut self) {
        for page in &mut self.pages {
            page.drain_background();
        }
    }

    pub fn render(&mut self, f: &mut ratatui::Frame, area: ratatui::layout::Rect) {
        let idx = self.ctx.active_page;
        self.pages[idx].render(f, &self.ctx, area);
    }

    pub fn on_fs_change(&mut self) -> Result<()> {
        for page in &mut self.pages {
            page.on_fs_change(&mut self.ctx)?;
        }
        Ok(())
    }

    pub fn on_tick(&mut self) {
        let idx = self.ctx.active_page;
        self.pages[idx].on_tick(&mut self.ctx);
    }

    pub fn on_suspend_return(
        &mut self,
        status: std::io::Result<std::process::ExitStatus>,
    ) -> Result<()> {
        let idx = self.ctx.active_page;
        self.pages[idx].on_suspend_return(&mut self.ctx, status)
    }

    /// Help entries of the active page, preceded by the page-switch keys of
    /// the app keymap (`1 / 2 / … `, "Switch view") when any page has one.
    pub fn active_help_bindings(&self) -> Vec<(String, String)> {
        let mut entries = Vec::new();
        let switch_keys = self
            .ctx
            .page_keys
            .iter()
            .flatten()
            .map(String::as_str)
            .collect::<Vec<_>>()
            .join(" / ");
        if !switch_keys.is_empty() {
            entries.push((switch_keys, "Switch view".to_string()));
        }
        entries.extend(self.pages[self.ctx.active_page].help_bindings());
        entries
    }

    pub fn handle_key(&mut self, key: KeyEvent) -> Result<PageAction> {
        if self.ctx.show_help {
            self.ctx.show_help = false;
            return Ok(PageAction::None);
        }

        // Error dialog: any key dismisses
        if self.ctx.error_dialog.is_some() {
            self.ctx.error_dialog = None;
            return Ok(PageAction::None);
        }

        let idx = self.ctx.active_page;

        // If the page intercepts all keys (modal menu, search input), delegate immediately
        if self.pages[idx].intercepts_all_keys() {
            return self.pages[idx].handle_key(&mut self.ctx, key);
        }

        // App-level keymap handles Quit and page switching.
        if let Some(action) = self.app_keymap.lookup(key) {
            match action.clone() {
                AppAction::Quit => {
                    self.ctx.should_quit = true;
                    return Ok(PageAction::None);
                }
                AppAction::SwitchPage(new_idx) => {
                    if new_idx < self.pages.len() && new_idx != idx {
                        self.ctx.active_page = new_idx;
                        self.pages[new_idx].on_activate(&mut self.ctx);
                    }
                    return Ok(PageAction::None);
                }
            }
        }

        // Delegate to active page
        self.pages[idx].handle_key(&mut self.ctx, key)
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::core::keymap::KeyInput;

    /// Regression guard for the page-switch bindings in `default.kdl`'s `app` block.
    ///
    /// The block references pages by their canonical id (`page:git`, `page:github`),
    /// so `App::new` must resolve those against [`PageState::id`] — not the display
    /// `label()` ("Git"/"GitHub"). Using `label()` made every `page:*` binding fail to
    /// resolve, which previously was silently dropped (1/2 page switching did nothing)
    /// and now panics via the embedded-default `expect`. This builds the keymap the
    /// same way `App::new` does, from the real pages, so the two can't drift apart.
    /// Every enabled page, created from `cfg` the way `run_tui` does
    /// (through the shared `pages::build_pages` registry, in slot order).
    fn all_pages(cfg: &Config) -> (Vec<Page>, PathBuf) {
        let cwd = std::env::current_dir().unwrap();
        crate::pages::build_pages(cfg, &cwd, None).expect("pages")
    }

    /// Build the `App` from `cfg` exactly as production does; `App::new`
    /// fails (failing the test) if the page ids ever drift from the
    /// `page:*` references in the config.
    fn app_with(cfg: &Config) -> App {
        let (pages, workdir) = all_pages(cfg);
        let ctx = AppContext {
            should_quit: false,
            active_page: 0,
            page_labels: pages.iter().map(|p| p.label()).collect(),
            page_keys: Vec::new(),
            show_help: false,
            status_message: None,
            error_dialog: None,
            workdir,
            needs_full_redraw: false,
        };
        App::new(ctx, pages, cfg).expect("app keymap")
    }

    fn user_config(kdl: &str) -> Config {
        let doc: kdl::KdlDocument = kdl.parse().unwrap();
        Config::with_user(&doc, PathBuf::from("/u/config.kdl")).expect("user config")
    }

    fn page_index(app: &App, id: &str) -> usize {
        app.pages.iter().position(|p| p.id() == id).unwrap()
    }

    fn labels(app: &App) -> Vec<&'static str> {
        app.ctx.page_labels.clone()
    }

    #[test]
    fn app_keymap_resolves_page_switch_bindings() {
        let cfg = Config::builtin();
        let app = app_with(&cfg);
        assert_eq!(
            labels(&app),
            [
                "Git",
                "GitHub",
                "Files",
                "Docker",
                "Procs",
                "Worktrees",
                "Projects"
            ],
            "builtin `pages` order defines the slots"
        );
        let procs_idx = page_index(&app, "procs");
        let worktrees_idx = page_index(&app, "worktrees");
        let projects_idx = page_index(&app, "projects");

        let look = |s: &str| {
            let ki: KeyInput = s.parse().unwrap();
            app.app_keymap
                .lookup(KeyEvent::new(ki.code, ki.modifiers))
                .cloned()
        };
        assert_eq!(look("1"), Some(AppAction::SwitchPage(0)));
        assert_eq!(look("2"), Some(AppAction::SwitchPage(1)));
        assert_eq!(look("3"), Some(AppAction::SwitchPage(2)));
        assert_eq!(look("4"), Some(AppAction::SwitchPage(3)));
        assert_eq!(look("5"), Some(AppAction::SwitchPage(procs_idx)));
        assert_eq!(look("6"), Some(AppAction::SwitchPage(worktrees_idx)));
        assert_eq!(look("7"), Some(AppAction::SwitchPage(projects_idx)));
        assert_eq!(look("8"), None);
        assert_eq!(look("Ctrl+c"), Some(AppAction::Quit));
    }

    /// The header tab labels and the help "Switch view" entry are derived
    /// from the `app { }` block, so a page bound to `6` shows `6`, not its
    /// position (`5`).
    #[test]
    fn page_keys_follow_the_builtin_app_block() {
        let app = app_with(&Config::builtin());
        let keys: Vec<Vec<&str>> = app
            .ctx
            .page_keys
            .iter()
            .map(|k| k.iter().map(String::as_str).collect())
            .collect();
        assert_eq!(
            keys,
            vec![
                vec!["1"],
                vec!["2"],
                vec!["3"],
                vec!["4"],
                vec!["5"],
                vec!["6"],
                vec!["7"]
            ]
        );
        let help = app.active_help_bindings();
        assert_eq!(
            help[0],
            (
                "1 / 2 / 3 / 4 / 5 / 6 / 7".to_string(),
                "Switch view".to_string()
            )
        );
        // Pages no longer add their own view-switch entry.
        assert_eq!(help.iter().filter(|(_, v)| v == "Switch view").count(), 1);
    }

    #[test]
    fn page_keys_follow_user_rebindings() {
        // An extra key is appended after the built-in one.
        let app = app_with(&user_config(r#"app { "w" "page:worktrees" }"#));
        let idx = page_index(&app, "worktrees");
        assert_eq!(app.ctx.page_keys[idx], vec!["6", "w"]);
        assert_eq!(
            app.active_help_bindings()[0].0,
            "1 / 2 / 3 / 4 / 5 / 6 / w / 7"
        );

        // Unbinding the built-in key leaves only the user's key, so the
        // header shows `w:Worktrees`.
        let app = app_with(&user_config(r#"app { "6" "None"; "w" "page:worktrees" }"#));
        let idx = page_index(&app, "worktrees");
        assert_eq!(app.ctx.page_keys[idx], vec!["w"]);
        assert_eq!(app.active_help_bindings()[0].0, "1 / 2 / 3 / 4 / 5 / w / 7");
    }

    /// `pages` reorders the slots: the header (`page_labels`) follows the
    /// listed order while keys keep addressing pages by name.
    #[test]
    fn user_pages_reorder_slots_and_keep_keys_by_name() {
        let app = app_with(&user_config(r#"pages "files" "git""#));
        assert_eq!(labels(&app), ["Files", "Git"]);
        assert_eq!(page_index(&app, "files"), 0, "slot 1 is Files");
        assert_eq!(app.ctx.page_keys, vec![vec!["3"], vec!["1"]]);
        assert_eq!(app.active_help_bindings()[0].0, "3 / 1");

        let mut app = app_with(&user_config(r#"pages "worktrees" "git""#));
        assert_eq!(labels(&app), ["Worktrees", "Git"]);
        assert_eq!(app.active_help_bindings()[0].0, "6 / 1");
        // Keys still switch to the page they name, wherever its slot is.
        let ki: KeyInput = "1".parse().unwrap();
        app.handle_key(KeyEvent::new(ki.code, ki.modifiers))
            .unwrap();
        assert_eq!(app.ctx.active_page, page_index(&app, "git"));
    }

    /// Disabled pages are not constructed; their built-in keys are dropped
    /// (so `2` does nothing) rather than being an error.
    #[test]
    fn user_pages_disable_pages() {
        let mut app = app_with(&user_config(r#"pages "git" "files" "worktrees""#));
        assert_eq!(labels(&app), ["Git", "Files", "Worktrees"]);
        assert_eq!(app.pages.len(), 3);
        assert_eq!(app.ctx.page_keys, vec![vec!["1"], vec!["3"], vec!["6"]]);
        assert_eq!(app.active_help_bindings()[0].0, "1 / 3 / 6");
        let ki: KeyInput = "2".parse().unwrap();
        assert!(app
            .app_keymap
            .lookup(KeyEvent::new(ki.code, ki.modifiers))
            .is_none());
        app.handle_key(KeyEvent::new(ki.code, ki.modifiers))
            .unwrap();
        assert_eq!(app.ctx.active_page, 0);
    }

    #[test]
    fn page_keys_helper_groups_by_page_in_insertion_order() {
        let km = build_app_keymap(
            &[
                ("Ctrl+c".to_string(), "Quit".to_string()),
                ("2".to_string(), "page:b".to_string()),
                ("1".to_string(), "page:a".to_string()),
                ("Space".to_string(), "page:b".to_string()),
                ("9".to_string(), "SwitchPage:9".to_string()),
            ],
            &["a", "b", "c"],
        )
        .unwrap();
        let keys = page_keys(&km, 3);
        assert_eq!(keys[0], vec!["1"]);
        assert_eq!(keys[1], vec!["2", "Space"]);
        assert!(keys[2].is_empty());
        assert_eq!(keys.len(), 3, "out-of-range page indices are ignored");
    }
}