//! Home screen — project list with stats overview.

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

use crate::format;

use super::App;

/// The project list's columns.
///
/// Title is the only one without which a row stops saying which project it is,
/// so it is the only [`Priority::Essential`] one. Revenue and status are what
/// this screen is opened for, which puts them above the type and the count when
/// the window narrows.
const PROJECT_COLUMNS: [Column<'static>; 5] = [
    Column {
        name: "Title",
        width: Width::Fill,
        priority: Priority::Essential,
        sortable: false,
        sorted: None,
    },
    Column {
        name: "Type",
        width: Width::Fixed,
        priority: Priority::Optional,
        sortable: false,
        sorted: None,
    },
    Column {
        name: "Status",
        width: Width::Fixed,
        priority: Priority::Secondary,
        sortable: false,
        sorted: None,
    },
    Column {
        name: "Items",
        width: Width::Fixed,
        priority: Priority::Optional,
        sortable: false,
        sorted: None,
    },
    Column {
        name: "Revenue",
        width: Width::Fixed,
        priority: Priority::Secondary,
        sortable: false,
        sorted: None,
    },
];

/// The tracks the hand-written `Constraint`s carried, lifted rather than
/// re-chosen. Revenue is wider than the amount alone needs: a three-character
/// symbol (`CA$`) plus the `+N` multi-currency marker has to fit without
/// truncating.
const PROJECT_SIZING: Sizing<'static> = Sizing {
    lengths: &[
        ("Title", 20),
        ("Type", 12),
        ("Status", 8),
        ("Items", 7),
        ("Revenue", 15),
    ],
    fallback: 8,
};

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

    let tier_label = app
        .user
        .creator_tier
        .as_deref()
        .map_or("No tier", format::format_tier);

    let title = Line::from(vec![
        Span::styled(
            " Makenot.work ",
            Style::default().add_modifier(Modifier::BOLD),
        ),
        Span::raw(" ── "),
        Span::styled(
            &app.user.username,
            Style::default().add_modifier(Modifier::BOLD),
        ),
        Span::raw(" ── "),
        Span::raw(tier_label),
        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(3), // stats bar
        Constraint::Length(1), // spacer
        Constraint::Length(1), // section header
        Constraint::Min(3),    // project list
        Constraint::Length(1), // keybindings
    ])
    .split(inner);

    // Stats bar
    render_stats(frame, app, chunks[1]);

    // Section header
    let header = Paragraph::new(Line::from(vec![
        Span::raw("  "),
        Span::styled("Projects", Style::default().add_modifier(Modifier::BOLD)),
        if app.projects.is_empty() {
            Span::raw("")
        } else {
            Span::raw(format!(" ({})", app.projects.len()))
        },
    ]));
    frame.render_widget(header, chunks[3]);

    // Project list
    if app.loading {
        let loading = Paragraph::new("  Loading...");
        frame.render_widget(loading, chunks[4]);
    } else if app.projects.is_empty() {
        let empty = Paragraph::new("  No projects yet. Create one at makenot.work/dashboard");
        frame.render_widget(empty, chunks[4]);
    } else {
        render_project_table(frame, app, chunks[4]);
    }

    // Keybindings
    let keys = Paragraph::new(Line::from(vec![
        Span::raw("  "),
        Span::styled("[j/k]", Style::default().add_modifier(Modifier::BOLD)),
        Span::raw(" Nav  "),
        Span::styled("[Enter]", Style::default().add_modifier(Modifier::BOLD)),
        Span::raw(" Open  "),
        Span::styled("[u]", Style::default().add_modifier(Modifier::BOLD)),
        Span::raw(" Upload  "),
        Span::styled("[a]", Style::default().add_modifier(Modifier::BOLD)),
        Span::raw(" Analytics  "),
        Span::styled("[p]", Style::default().add_modifier(Modifier::BOLD)),
        Span::raw(" Promo  "),
        Span::styled("[c]", Style::default().add_modifier(Modifier::BOLD)),
        Span::raw(" Collections  "),
        Span::styled("[s]", Style::default().add_modifier(Modifier::BOLD)),
        Span::raw(" Settings  "),
        Span::styled("[q]", Style::default().add_modifier(Modifier::BOLD)),
        Span::raw(" Quit"),
    ]))
    .style(Style::default().fg(app.theme.content_muted));
    frame.render_widget(keys, chunks[5]);
}

fn render_stats(frame: &mut Frame, app: &App, area: ratatui::layout::Rect) {
    let stats_chunks = Layout::horizontal([
        Constraint::Ratio(1, 4),
        Constraint::Ratio(1, 4),
        Constraint::Ratio(1, 4),
        Constraint::Ratio(1, 4),
    ])
    .split(area);

    let (revenue, sales, followers, items) = if let Some(ref s) = app.stats {
        (
            format::format_cents(s.current_revenue_cents, app.currency()),
            s.current_sales.to_string(),
            s.current_followers.to_string(),
            s.total_items.to_string(),
        )
    } else {
        ("--".into(), "--".into(), "--".into(), "--".into())
    };

    let stat_items = [
        ("Revenue", &revenue),
        ("Sales", &sales),
        ("Followers", &followers),
        ("Items", &items),
    ];

    for (i, (label, value)) in stat_items.iter().enumerate() {
        let block = Block::default()
            .borders(Borders::ALL)
            .border_style(Style::default().fg(app.theme.content_muted));
        let inner = block.inner(stats_chunks[i]);
        frame.render_widget(block, stats_chunks[i]);

        let text = Paragraph::new(Line::from(vec![
            Span::styled(
                format!(" {value}"),
                Style::default().add_modifier(Modifier::BOLD),
            ),
            Span::styled(
                format!(" {label}"),
                Style::default().fg(app.theme.content_muted),
            ),
        ]));
        frame.render_widget(text, inner);
    }
}

fn render_project_table(frame: &mut Frame, app: &App, area: Rect) {
    let area = super::indent(area, 2);

    let rows: Vec<Vec<Cell>> = app
        .projects
        .iter()
        .map(|p| {
            vec![
                Cell::new("Title", p.title.as_str()),
                Cell::new("Type", format::format_project_type(&p.project_type)),
                Cell::new("Status", if p.is_public { "public" } else { "draft" }),
                Cell::new("Items", p.item_count.to_string()),
                Cell::new("Revenue", p.revenue().display_compact(app.currency())),
            ]
        })
        .collect();

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