//! Project detail screen — item list within a project.

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::api::Project;
use crate::format;

use super::App;

/// The item list's columns.
///
/// Title carries the selection marker as well as the name, so it is what a row
/// identifies itself by and the price is what the creator is checking. Type and
/// status drop first.
const ITEM_COLUMNS: [Column<'static>; 4] = [
    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: "Price",
        width: Width::Fixed,
        priority: Priority::Secondary,
        sortable: false,
        sorted: None,
    },
    Column {
        name: "Status",
        width: Width::Fixed,
        priority: Priority::Secondary,
        sortable: false,
        sorted: None,
    },
];

/// The tracks the hand-written `Constraint`s carried.
const ITEM_SIZING: Sizing<'static> = Sizing {
    lengths: &[("Title", 20), ("Type", 12), ("Price", 10), ("Status", 8)],
    fallback: 8,
};

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

    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(" "),
    ]);

    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 has_confirm = app.confirm_action.is_some();
    let has_status = app.item_status.is_some();

    let chunks = Layout::vertical([
        Constraint::Length(1),                                    // spacer
        Constraint::Length(1),                                    // project info line
        Constraint::Length(1),                                    // spacer
        Constraint::Length(1),                                    // section header
        Constraint::Min(3),                                       // item list
        Constraint::Length(u16::from(has_confirm || has_status)), // status/confirm
        Constraint::Length(1),                                    // keybindings
    ])
    .split(inner);

    // Project info
    let visibility = if project.is_public { "public" } else { "draft" };
    let info = Paragraph::new(Line::from(vec![
        Span::raw("  "),
        Span::styled(&project.slug, Style::default().fg(app.theme.content_muted)),
        Span::raw("  "),
        Span::raw(format::format_project_type(&project.project_type)),
        Span::raw("  "),
        Span::raw(visibility),
        Span::raw("  "),
        // The detail line has the room for the full breakdown, so a project
        // spanning two currencies shows both here rather than a `+1` marker.
        Span::raw(project.revenue().display(app.currency())),
        Span::styled(" revenue", Style::default().fg(app.theme.content_muted)),
    ]));
    frame.render_widget(info, chunks[1]);

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

    // Item list
    if app.loading {
        let loading = Paragraph::new("  Loading...");
        frame.render_widget(loading, chunks[4]);
    } else if app.items.is_empty() {
        let empty = Paragraph::new("  No items in this project.");
        frame.render_widget(empty, chunks[4]);
    } else {
        render_item_table(frame, app, chunks[4]);
    }

    // Status / confirmation line
    if let Some(ref action) = app.confirm_action {
        let msg = match action {
            super::ConfirmAction::BulkPublish { count } => {
                format!("  Publish {count} items? [y/n]")
            }
            super::ConfirmAction::BulkUnpublish { count } => {
                format!("  Unpublish {count} items? [y/n]")
            }
            super::ConfirmAction::BulkDelete { count } => {
                format!("  Delete {count} items? This cannot be undone. [y/n]")
            }
            _ => String::new(),
        };
        let confirm = Paragraph::new(msg).style(Style::default().fg(app.theme.status_warning));
        frame.render_widget(confirm, chunks[5]);
    } else if let Some(ref status) = app.item_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[5]);
    }

    // Keybindings
    let sel_count = app.selected_items.len();
    let mut key_spans = vec![
        Span::raw("  "),
        Span::styled("[j/k]", Style::default().add_modifier(Modifier::BOLD)),
        Span::raw(" Nav  "),
    ];

    if !app.items.is_empty() {
        key_spans.extend([
            Span::styled("[Space]", Style::default().add_modifier(Modifier::BOLD)),
            Span::raw(" Select  "),
            Span::styled("[Enter]", Style::default().add_modifier(Modifier::BOLD)),
            Span::raw(" Open  "),
            Span::styled("[p]", Style::default().add_modifier(Modifier::BOLD)),
            Span::raw(" Pub/Unpub  "),
            Span::styled("[d]", Style::default().add_modifier(Modifier::BOLD)),
            Span::raw(" Delete  "),
        ]);
    }

    if sel_count > 0 {
        key_spans.extend([
            Span::styled(
                format!("{sel_count} selected"),
                Style::default()
                    .fg(app.theme.action_primary)
                    .add_modifier(Modifier::BOLD),
            ),
            Span::raw("  "),
        ]);
    }

    key_spans.extend([
        Span::styled("[b]", Style::default().add_modifier(Modifier::BOLD)),
        Span::raw(" Blog  "),
        Span::styled("[t]", Style::default().add_modifier(Modifier::BOLD)),
        Span::raw(" Tiers  "),
        Span::styled("[r]", Style::default().add_modifier(Modifier::BOLD)),
        Span::raw(" Refresh  "),
        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[6]);
}

fn render_item_table(frame: &mut Frame, app: &App, area: Rect) {
    let area = super::indent(area, 2);
    let has_selections = !app.selected_items.is_empty();

    let rows: Vec<Vec<Cell>> = app
        .items
        .iter()
        .enumerate()
        .map(|(i, item)| {
            // The checkbox appears only once something is selected, so a list
            // nobody has marked up reads as a plain list.
            let title = if has_selections {
                let marker = if app.selected_items.contains(&i) {
                    "[x]"
                } else {
                    "[ ]"
                };
                format!("{marker} {}", item.title)
            } else {
                item.title.clone()
            };

            vec![
                Cell::new("Title", title),
                Cell::new("Type", format::format_item_type(&item.item_type)),
                Cell::new(
                    "Price",
                    format::format_price(item.price_cents, app.currency()),
                ),
                Cell::new("Status", if item.is_public { "public" } else { "draft" }),
            ]
        })
        .collect();

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