//! Hello World example for zcatui.
//!
//! Demonstrates basic usage of the library:
//! - Creating a Terminal
//! - Rendering a Block with a title
//! - Using Layout to split the screen
//! - Displaying a Paragraph

const std = @import("std");
const zcatui = @import("zcatui");

const Terminal = zcatui.Terminal;
const Buffer = zcatui.Buffer;
const Rect = zcatui.Rect;
const Layout = zcatui.Layout;
const Constraint = zcatui.Constraint;
const Style = zcatui.Style;
const Color = zcatui.Color;
const block_mod = @import("zcatui").widgets.block_mod;
const Block = block_mod.Block;
const Borders = block_mod.Borders;
const Paragraph = zcatui.widgets.Paragraph;

pub fn main() !void {
    var gpa = std.heap.GeneralPurposeAllocator(.{}){};
    defer _ = gpa.deinit();
    const allocator = gpa.allocator();

    // Initialize terminal
    var term = try Terminal.init(allocator);
    defer term.deinit();

    // Draw the UI
    try term.draw(render);

    // Wait for 'q' to quit
    const stdin = std.fs.File.stdin();
    var buf: [1]u8 = undefined;
    while (true) {
        const bytes_read = stdin.read(&buf) catch break;
        if (bytes_read == 0) break;
        if (buf[0] == 'q') break;

        // Redraw on any key
        try term.draw(render);
    }
}

fn render(area: Rect, buf: *Buffer) void {
    // Split screen: header (3 rows) + content (rest)
    const chunks = Layout.vertical(&.{
        Constraint.length(3),
        Constraint.min(0),
    }).split(area);

    // Header block
    const header = Block.init()
        .title(" zcatui Demo ")
        .setBorders(Borders.all)
        .borderStyle(Style.default.fg(Color.cyan));

    header.render(chunks.get(0), buf);

    // Content area with paragraph
    const content_block = Block.init()
        .title(" Welcome ")
        .setBorders(Borders.all)
        .borderStyle(Style.default.fg(Color.green));

    const content_area = chunks.get(1);
    content_block.render(content_area, buf);

    // Paragraph inside the content block
    const text =
        \\Hello from zcatui!
        \\
        \\This is a TUI library for Zig, inspired by ratatui.
        \\
        \\Features:
        \\  - Immediate mode rendering
        \\  - Layout system with constraints
        \\  - Styled text and colors
        \\  - Reusable widgets
        \\
        \\Press 'q' to quit.
    ;

    const para = Paragraph.init(text)
        .style(Style.default.fg(Color.white))
        .setWrap(.word);

    para.render(content_block.inner(content_area), buf);
}