//! Subscription tier list screen — read-only view of project tiers.

use makeover_tui::makeover_layout::{Column, Priority, Width};
use makeover_tui::table::{self, Cell, Sizing, TableStyle};
use ratatui::Frame;
use ratatui::layout::{Constraint, Layout};
use ratatui::style::{Modifier, Style};
use ratatui::text::{Line, Span};
use ratatui::widgets::{Block, Borders, Paragraph, TableState};

use crate::format;

use super::App;

/// The subscription tier columns. A tier is a name and a price, so both are
/// essential; the description is the first thing to go.
const TIER_COLUMNS: [Column<'static>; 4] = [
    Column {
        name: "Name",
        width: Width::Fill,
        priority: Priority::Essential,
        sortable: false,
        sorted: None,
    },
    Column {
        name: "Price",
        width: Width::Fixed,
        priority: Priority::Essential,
        sortable: false,
        sorted: None,
    },
    Column {
        name: "Status",
        width: Width::Fixed,
        priority: Priority::Secondary,
        sortable: false,
        sorted: None,
    },
    Column {
        name: "Description",
        width: Width::Fixed,
        priority: Priority::Optional,
        sortable: false,
        sorted: None,
    },
];

/// The tracks the hand-written `Constraint`s carried. The description is
/// truncated to fit its 30, which is why it is a fixed track and not a fill.
const TIER_SIZING: Sizing<'static> = Sizing {
    lengths: &[
        ("Name", 16),
        ("Price", 10),
        ("Status", 10),
        ("Description", 30),
    ],
    fallback: 10,
};

pub(crate) fn render(frame: &mut Frame, app: &App) {
    let area = frame.area();

    let project_title = app.tiers_project_title.as_deref().unwrap_or("Project");

    let title = Line::from(vec![
        Span::styled(
            " Makenot.work ",
            Style::default().add_modifier(Modifier::BOLD),
        ),
        Span::raw(" -- "),
        Span::styled(project_title, Style::default().add_modifier(Modifier::BOLD)),
        Span::raw(" -- "),
        Span::styled(
            "Subscription Tiers",
            Style::default().add_modifier(Modifier::BOLD),
        ),
        Span::raw(" "),
    ]);

    let block = Block::default()
        .title(title)
        .borders(Borders::ALL)
        .border_style(Style::default().fg(app.theme.line_border));

    let inner = block.inner(area);
    frame.render_widget(block, area);

    let chunks = Layout::vertical([
        Constraint::Length(1), // spacer
        Constraint::Length(1), // section header
        Constraint::Min(3),    // list
        Constraint::Length(1), // status line
        Constraint::Length(1), // keybindings
    ])
    .split(inner);

    let count = app.tiers.len();
    let header = Paragraph::new(Line::from(vec![
        Span::raw("  "),
        Span::styled("Tiers", Style::default().add_modifier(Modifier::BOLD)),
        if count == 0 {
            Span::raw("")
        } else {
            Span::raw(format!(" ({count})"))
        },
    ]));
    frame.render_widget(header, chunks[1]);

    if app.loading {
        let loading = Paragraph::new("  Loading...");
        frame.render_widget(loading, chunks[2]);
    } else if app.tiers.is_empty() {
        let empty = Paragraph::new("  No subscription tiers for this project.");
        frame.render_widget(empty, chunks[2]);
    } else {
        let area = super::indent(chunks[2], 2);
        let rows: Vec<Vec<Cell>> = app
            .tiers
            .iter()
            .map(|t| {
                let desc = if t.description.len() > 30 {
                    format!("{}...", &t.description[..27])
                } else {
                    t.description.clone()
                };
                vec![
                    Cell::new("Name", t.name.as_str()),
                    Cell::new("Price", format::format_price(t.price_cents, app.currency())),
                    Cell::new("Status", if t.is_active { "active" } else { "inactive" }),
                    Cell::new("Description", desc),
                ]
            })
            .collect();

        let style = TableStyle::from_theme(&app.theme);
        let table = table::table(&TIER_COLUMNS, &rows, &TIER_SIZING, &style, area.width);
        let mut state = TableState::default().with_selected(Some(app.selected_index));
        frame.render_stateful_widget(table, area, &mut state);
    }

    if let Some(ref status) = app.tiers_status {
        let style = if status.starts_with("Error") {
            Style::default().fg(app.theme.status_danger)
        } else {
            Style::default().fg(app.theme.status_success)
        };
        let status_line = Paragraph::new(format!("  {status}")).style(style);
        frame.render_widget(status_line, chunks[3]);
    }

    let key_spans = vec![
        Span::raw("  "),
        Span::styled("[j/k]", Style::default().add_modifier(Modifier::BOLD)),
        Span::raw(" Nav  "),
        Span::styled("[Esc]", Style::default().add_modifier(Modifier::BOLD)),
        Span::raw(" Back"),
    ];

    let keys =
        Paragraph::new(Line::from(key_spans)).style(Style::default().fg(app.theme.content_muted));
    frame.render_widget(keys, chunks[4]);
}