ui.reef - zygaena/zyginit

root / src / ui.reef
ui.reef Reef 986 lines 34.7 KB
/******************************************************************************
                __               ____                __
               / /   ___  ____ _/ __/_____________ _/ /__
              / /   / _ \/ __ `/ /_/ ___/ ___/ __ `/ / _ \
             / /___/  __/ /_/ / __(__  ) /__/ /_/ / /  __/
            /_____/\___/\__,_/_/ /____/\___/\__,_/_/\___/

    (C)opyright 2025-2026, Leafscale, LLC -  https://www.leafscale.com

    Project: zyginit
   Filename: ui.reef
    Authors: Chris Tusa <chris.tusa@leafscale.com>
    License: <see LICENSE file included with this source code>
Description: Unified visual rendering: palette, glyphs, sigil, rolling tape, progress bar, spinner, final cards.
     
******************************************************************************/

module ui

import core.str as str
import sys.env as env
import sys.process as process
import time.time as time
import version

export
    fn MODE_PLAIN(): int
    fn MODE_RICH_ASCII(): int
    fn MODE_RICH_16(): int
    fn MODE_RICH_TRUE(): int
    proc ui_init(rich_mode: int)
    fn ui_mode(): int
    fn ui_runlevel(): string
    fn ui_demo(scenario: string): int
    fn detect_rich_mode(): int
    fn detect_rich_mode_for_main(): int
    fn paint(token: string, text: string): string
    fn glyph_ok(): string
    fn glyph_fail(): string
    fn glyph_pending(): string
    fn glyph_starting(): string
    fn sigil(): string
    proc ui_boot_start(num_svc: int, num_tiers: int, runlevel: string)
    proc ui_tier_start(tier: int)
    proc ui_tier_done(tier: int)
    proc ui_event_started(name: string, dur_ms: int)
    proc ui_event_failed(name: string, exit_code: int, dur_ms: int)
    proc ui_event_starting(name: string)
    proc ui_event_stopping(name: string)
    proc ui_tick()
    fn ui_spinner_frame(reverse: bool): string
    fn fmt_progress_bar(done: int, total: int): string
    type BootStats
    proc ui_boot_complete(stats: BootStats)
    proc ui_shutdown_start(reason: string)
    proc ui_event_stopped(name: string, dur_ms: int)
    proc ui_shutdown_complete(reason: string, elapsed_ms: int)
    fn pad_right(s: string, n: int): string
    fn make_divider(): string
    proc ui_set_mode(m: int)
    fn zyginit_monotonic_ms(): int
end export

type BootStats = struct
    elapsed_ms: int
    online: int
    failed: int
    slowest: [string]
    slowest_count: int
end BootStats

// Render modes. Decided once at startup by ui_init().
fn MODE_PLAIN(): int        return 0   end MODE_PLAIN
fn MODE_RICH_ASCII(): int   return 1   end MODE_RICH_ASCII
fn MODE_RICH_16(): int      return 2   end MODE_RICH_16
fn MODE_RICH_TRUE(): int    return 3   end MODE_RICH_TRUE

mut g_mode: int = 0
mut g_failed: bool = false   // set if write() to /dev/console errors

// Declared here (before TAPE_HEIGHT) so the C prototype is emitted before
// its first use; also appears grouped with the other tape externs below.
extern "C" fn zyginit_tape_slots(): int
fn TAPE_HEIGHT(): int return zyginit_tape_slots() end TAPE_HEIGHT

mut g_phase: string = ""
mut g_runlevel: string = ""
mut g_num_svc: int = 0
mut g_num_tiers: int = 0
mut g_cur_tier: int = 0
mut g_done: int = 0
mut g_failed_count: int = 0
mut g_failed_first: string = ""
mut g_failed_first_exit: int = 0
mut g_boot_start_ms: int = 0
mut g_shutdown_reason: string = ""

// Spinner state
mut g_tick: int = 0
mut g_starting_name: string = ""
mut g_stopping_name: string = ""

// Tape state counters. The backing arrays live in helpers.c (C static buffers)
// to avoid Reef's module-level new[] limitation (Reef emits GCC statement-expr
// initializers which are invalid as C static initializers).
mut g_tape_head: int = 0
mut g_tape_count: int = 0

extern "C" fn zyginit_isatty(fd: int): int
extern "C" fn zyginit_esc_str(): string
extern "C" fn zyginit_monotonic_ms(): int
extern "C" fn zyginit_tape_slots(): int
extern "C" proc zyginit_tape_clear()
extern "C" proc zyginit_tape_set(slot: int, elapsed: int, glyph: string, name: string, note: string)
extern "C" fn zyginit_tape_get_elapsed(slot: int): int
extern "C" fn zyginit_tape_get_glyph(slot: int): string
extern "C" fn zyginit_tape_get_name(slot: int): string
extern "C" fn zyginit_tape_get_note(slot: int): string

fn N_FRAMES(): int return 4 end N_FRAMES

// Return the current spinner frame character.
// Forward (starting): cycles / - \ |  with increasing g_tick
// Reverse (stopping): cycles | \ - /  with increasing g_tick (unwinds)
fn ui_spinner_frame(reverse: bool): string
    let i = g_tick % N_FRAMES()
    if reverse
        let r = (N_FRAMES() - 1) - i
        if r == 0  return "/"  end if
        if r == 1  return "-"  end if
        if r == 2  return "\\"  end if
        return "|"
    end if
    if i == 0  return "/"  end if
    if i == 1  return "-"  end if
    if i == 2  return "\\"  end if
    return "|"
end ui_spinner_frame

// Pure terminal capability detector (no PID check, no isatty check).
// Inspects only env vars and TERM. Use this from --ui-demo and snapshot tests.
// Production callers (main.reef boot path) should use
// detect_rich_mode_for_main() — it adds the PID-1 and isatty guards.
fn detect_rich_mode(): int
    if env.has_env("ZYGINIT_NO_UI")     return MODE_PLAIN()      end if
    if env.has_env("NO_COLOR")          return MODE_PLAIN()      end if
    let term = env.get_env_or("TERM", "")
    if term == "dumb"                   return MODE_PLAIN()      end if
    if env.has_env("ZYGINIT_ASCII")     return MODE_RICH_ASCII() end if
    if term == "sun"                    return MODE_RICH_16()    end if
    if term == "vt100"                  return MODE_RICH_16()    end if
    if term == "vt220"                  return MODE_RICH_16()    end if
    if term == "sun-color"              return MODE_RICH_TRUE()  end if
    if str.index_of(term, "256color") >= 0
        return MODE_RICH_TRUE()
    end if
    // Hammerhead UEFI framebuffer: kernel doesn't set TERM but tem
    // supports full ANSI/CSI/truecolor. Default to truecolor when
    // we have no TERM hint.
    if str.length(term) == 0            return MODE_RICH_TRUE()  end if
    // Anything else: safe 16-color baseline.
    return MODE_RICH_16()
end detect_rich_mode

// PID-1-aware, tty-aware wrapper around detect_rich_mode.
// Adds: non-PID-1 instances always emit plain; non-tty stdout always emits plain.
// Call this from main.reef boot path; call detect_rich_mode() for tests/demo.
fn detect_rich_mode_for_main(): int
    // Hard overrides
    if env.has_env("ZYGINIT_NO_UI")  return MODE_PLAIN()  end if
    if env.has_env("NO_COLOR")       return MODE_PLAIN()  end if
    // Production gates
    if process.getpid() != 1         return MODE_PLAIN()  end if
    if zyginit_isatty(1) == 0        return MODE_PLAIN()  end if
    // TERM-driven mode
    let term = env.get_env_or("TERM", "")
    if term == "dumb"                return MODE_PLAIN()      end if
    if env.has_env("ZYGINIT_ASCII")  return MODE_RICH_ASCII() end if
    if term == "sun"                 return MODE_RICH_16()    end if
    if term == "vt100"               return MODE_RICH_16()    end if
    if term == "vt220"               return MODE_RICH_16()    end if
    if term == "sun-color"           return MODE_RICH_TRUE()  end if
    if str.index_of(term, "256color") >= 0
        return MODE_RICH_TRUE()
    end if
    // Hammerhead UEFI framebuffer: kernel doesn't set TERM but tem
    // supports full ANSI/CSI/truecolor. Default to truecolor when we
    // have a tty but no TERM hint.
    if str.length(term) == 0         return MODE_RICH_TRUE()  end if
    // Anything else: safe 16-color baseline.
    return MODE_RICH_16()
end detect_rich_mode_for_main

// SGR escape sequences. ESC char via C helper (Reef lexer has no \x escapes).
// esc_reset returns the SGR reset sequence "\e[0m".
fn esc_reset(): string
    return str.concat(zyginit_esc_str(), "[0m")
end esc_reset

// 16-color foreground codes.
fn sgr_steel(): string  return str.concat(zyginit_esc_str(), "[37m")   end sgr_steel
fn sgr_teal(): string   return str.concat(zyginit_esc_str(), "[36m")   end sgr_teal
fn sgr_ok(): string     return str.concat(zyginit_esc_str(), "[32m")   end sgr_ok
fn sgr_warn(): string   return str.concat(zyginit_esc_str(), "[33m")   end sgr_warn
fn sgr_fail(): string   return str.concat(zyginit_esc_str(), "[31m")   end sgr_fail
fn sgr_mute(): string   return str.concat(zyginit_esc_str(), "[2m")    end sgr_mute

// Truecolor foreground codes.
fn sgr_steel_true(): string return str.concat(zyginit_esc_str(), "[38;2;110;123;139m")  end sgr_steel_true
fn sgr_teal_true(): string  return str.concat(zyginit_esc_str(), "[38;2;0;106;111m")    end sgr_teal_true
fn sgr_ok_true(): string    return str.concat(zyginit_esc_str(), "[38;2;46;139;87m")    end sgr_ok_true
fn sgr_warn_true(): string  return str.concat(zyginit_esc_str(), "[38;2;255;191;0m")    end sgr_warn_true
fn sgr_fail_true(): string  return str.concat(zyginit_esc_str(), "[38;2;200;32;31m")    end sgr_fail_true

// Wrap text in the given palette token, honoring g_mode.
fn paint(token: string, text: string): string
    if g_mode == MODE_PLAIN()  return text  end if
    mut on = ""
    if g_mode == MODE_RICH_TRUE()
        if token == "frame"       on = sgr_steel_true()
        elif token == "accent"    on = sgr_teal_true()
        elif token == "ok"        on = sgr_ok_true()
        elif token == "warn"      on = sgr_warn_true()
        elif token == "fail"      on = sgr_fail_true()
        elif token == "mute"      on = sgr_mute()
        end if
    else
        if token == "frame"       on = sgr_steel()
        elif token == "accent"    on = sgr_teal()
        elif token == "ok"        on = sgr_ok()
        elif token == "warn"      on = sgr_warn()
        elif token == "fail"      on = sgr_fail()
        elif token == "mute"      on = sgr_mute()
        end if
    end if
    return str.concat(str.concat(on, text), esc_reset())
end paint

// Glyphs. Selected by g_mode.
fn glyph_ok(): string
    if g_mode == MODE_RICH_ASCII() return "#"   end if
    if g_mode == MODE_PLAIN()      return "ok"  end if
    return "●"
end glyph_ok

fn glyph_fail(): string
    if g_mode == MODE_RICH_ASCII() return "X"    end if
    if g_mode == MODE_PLAIN()      return "fail" end if
    return "✕"
end glyph_fail

fn glyph_pending(): string
    if g_mode == MODE_RICH_ASCII() return "."       end if
    if g_mode == MODE_PLAIN()      return "pending" end if
    return "·"
end glyph_pending

fn glyph_starting(): string
    if g_mode == MODE_RICH_ASCII() return "o"        end if
    if g_mode == MODE_PLAIN()      return "starting" end if
    return "◉"
end glyph_starting

// Sigil: "[Z]" colored c.accent in rich modes.
fn sigil(): string
    return paint("accent", "[Z]")
end sigil

// Plain-mode line: "  <elapsed-s>  <level>  <event>     <name>  [k=v ...]"
fn fmt_plain_event(elapsed_ms: int, level: string, event: string,
                   name: string, kv: string): string
    let secs = int_to_str(elapsed_ms / 1000)
    // centiseconds: truncate the within-second remainder to 0-99 (2 digits)
    let frac = int_to_str((elapsed_ms % 1000) / 10)
    mut pad = ""
    if str.length(frac) < 2  pad = "0"  end if
    mut line = str.concat("  ", secs)
    line = str.concat(line, ".")
    line = str.concat(line, pad)
    line = str.concat(line, frac)
    line = str.concat(line, "  ")
    line = str.concat(line, level)
    line = str.concat(line, "  ")
    line = str.concat(line, event)
    line = str.concat(line, "  ")
    line = str.concat(line, name)
    if str.length(kv) > 0
        line = str.concat(line, "  ")
        line = str.concat(line, kv)
    end if
    return line
end fmt_plain_event

proc tape_push(elapsed_ms: int, glyph: string, name: string, note: string)
    let slot = g_tape_head % TAPE_HEIGHT()
    zyginit_tape_set(slot, elapsed_ms, glyph, name, note)
    g_tape_head = g_tape_head + 1
    if g_tape_count < TAPE_HEIGHT()
        g_tape_count = g_tape_count + 1
    end if
end tape_push

fn fmt_tape_row(row_elapsed_ms: int, row_glyph: string, row_name: string, row_note: string): string
    let secs = row_elapsed_ms / 1000
    let frac = (row_elapsed_ms % 1000) / 10
    mut sf = int_to_str(frac)
    if str.length(sf) < 2  sf = str.concat("0", sf)  end if
    let elapsed = str.concat(str.concat(int_to_str(secs), "."), sf)
    mut pad = ""
    let pad_n = 6 - str.length(elapsed)
    mut i = 0
    while i < pad_n
        pad = str.concat(pad, " ")
        i = i + 1
    end while
    mut row = str.concat(pad, elapsed)
    row = str.concat(row, "  ")
    row = str.concat(row, row_glyph)
    row = str.concat(row, "  ")
    row = str.concat(row, row_name)
    if str.length(row_note) > 0
        row = str.concat(row, "  ")
        row = str.concat(row, paint("mute", str.concat(str.concat("(", row_note), ")")))
    end if
    return row
end fmt_tape_row

fn make_divider(): string
    mut div = ""
    mut k = 0
    while k < 62
        div = str.concat(div, "─")
        k = k + 1
    end while
    return div
end make_divider

fn fmt_header(elapsed_ms: int): string
    let secs = elapsed_ms / 1000
    let frac = (elapsed_ms % 1000) / 100
    let elapsed = str.concat(str.concat(int_to_str(secs), "."), str.concat(int_to_str(frac), "s"))
    let phase_label = g_runlevel
    mut out = str.concat("  ", sigil())
    out = str.concat(out, str.concat(" zyginit ", str.concat(version.VERSION(), " · ")))
    out = str.concat(out, paint("frame", phase_label))
    out = str.concat(out, "   ")
    out = str.concat(out, paint("accent", str.concat("elapsed ", elapsed)))
    out = str.concat(out, "\n  ")
    out = str.concat(out, paint("frame",
        str.concat(str.concat(int_to_str(g_num_svc), " services · tier "),
        str.concat(str.concat(int_to_str(g_cur_tier), " · "),
        str.concat(str.concat(int_to_str(g_done), " done · "),
        str.concat(int_to_str(g_failed_count), " failed"))))))
    out = str.concat(out, "\n  ")
    if g_failed_count == 0
        out = str.concat(out, paint("mute", "failed: none"))
    elif g_failed_count == 1
        out = str.concat(out, paint("fail",
            str.concat(str.concat("failed: ", g_failed_first),
            str.concat("  exit=", int_to_str(g_failed_first_exit)))))
    else
        out = str.concat(out, paint("fail",
            str.concat(str.concat("failed: ", int_to_str(g_failed_count)),
            " services")))
    end if
    out = str.concat(out, "\n  ")
    out = str.concat(out, paint("accent", make_divider()))
    return out
end fmt_header

fn PROGRESS_WIDTH(): int return 36 end PROGRESS_WIDTH

fn fmt_progress_bar(done: int, total: int): string
    if g_mode == MODE_PLAIN()  return ""  end if
    let width = PROGRESS_WIDTH()
    mut filled = 0
    if total > 0
        filled = (done * width) / total
    end if
    if filled > width  filled = width  end if
    mut pct = 0
    if total > 0
        pct = (done * 100) / total
    end if
    mut bar = ""
    if g_mode == MODE_RICH_ASCII()
        let inner = width - 2
        let inner_filled = (filled * inner) / width
        bar = str.concat(bar, "[")
        mut i = 0
        while i < inner
            if i < inner_filled
                bar = str.concat(bar, "#")
            else
                bar = str.concat(bar, " ")
            end if
            i = i + 1
        end while
        bar = str.concat(bar, "]")
    else
        mut i = 0
        while i < width
            if i < filled
                bar = str.concat(bar, paint("accent", "█"))
            else
                bar = str.concat(bar, paint("mute", "░"))
            end if
            i = i + 1
        end while
    end if
    mut label = ""
    if g_phase == "shutdown"  label = " down"  end if
    return str.concat(
        str.concat("  ", bar),
        str.concat(
            str.concat(str.concat("  ", int_to_str(done)),
                       str.concat("/", int_to_str(total))),
            str.concat(label, str.concat("  ", str.concat(int_to_str(pct), "%")))))
end fmt_progress_bar

// Render a single tape row, overriding the stored glyph with the current
// spinner frame when the row belongs to the active starting/stopping service.
fn fmt_tape_row_at(slot: int): string
    let elapsed_ms = zyginit_tape_get_elapsed(slot)
    let name = zyginit_tape_get_name(slot)
    let note = zyginit_tape_get_note(slot)
    let stored_glyph = zyginit_tape_get_glyph(slot)
    mut glyph = stored_glyph
    if str.length(g_starting_name) > 0 and name == g_starting_name
        glyph = paint("warn", ui_spinner_frame(false))
    end if
    if str.length(g_stopping_name) > 0 and name == g_stopping_name
        glyph = paint("warn", ui_spinner_frame(true))
    end if
    return fmt_tape_row(elapsed_ms, glyph, name, note)
end fmt_tape_row_at

fn render_boot_screen(elapsed_ms: int): string
    if g_mode == MODE_PLAIN()
        return ""
    end if
    mut out = str.concat(fmt_header(elapsed_ms), "\n")
    let start = g_tape_head - g_tape_count
    mut i = 0
    while i < TAPE_HEIGHT()
        if i < g_tape_count
            let slot = (start + i) % TAPE_HEIGHT()
            out = str.concat(out, fmt_tape_row_at(slot))
        end if
        out = str.concat(out, "\n")
        i = i + 1
    end while
    out = str.concat(out, str.concat("  ", paint("accent", make_divider())))
    out = str.concat(out, "\n")
    out = str.concat(out, fmt_progress_bar(g_done, g_num_svc))
    out = str.concat(out, "\n")
    return out
end render_boot_screen

// Advance the tick counter and, if in rich mode with an active spinner, redraw.
proc ui_tick()
    g_tick = g_tick + 1
    if g_mode == MODE_PLAIN()  return  end if
    if str.length(g_starting_name) == 0 and str.length(g_stopping_name) == 0
        return
    end if
    let elapsed = zyginit_monotonic_ms() - g_boot_start_ms
    print(str.concat(str.concat(zyginit_esc_str(), "[2J"),
          str.concat(zyginit_esc_str(), "[H")))
    print(render_boot_screen(elapsed))
end ui_tick

// Rich-mode-only redraw. Plain mode emits its own line before calling this.
proc emit_redraw(elapsed_ms: int)
    if g_mode == MODE_PLAIN()  return  end if
    print(str.concat(str.concat(zyginit_esc_str(), "[2J"),
          str.concat(zyginit_esc_str(), "[H")))
    print(render_boot_screen(elapsed_ms))
end emit_redraw

proc ui_boot_start(num_svc: int, num_tiers: int, runlevel: string)
    g_phase = "boot"
    g_runlevel = runlevel
    g_num_svc = num_svc
    g_num_tiers = num_tiers
    g_cur_tier = 0
    g_done = 0
    g_failed_count = 0
    g_failed_first = ""
    g_failed_first_exit = 0
    g_tape_head = 0
    g_tape_count = 0
    zyginit_tape_clear()
    g_boot_start_ms = zyginit_monotonic_ms()
end ui_boot_start

proc ui_tier_start(tier: int)
    g_cur_tier = tier
end ui_tier_start

proc ui_tier_done(tier: int)
    // header repaints happen via emit_redraw on next event/tick
end ui_tier_done

// dur_ms: service's own runtime (from supervisor). Reserved for future
// use (Task 6 spinner display); the tape currently shows wall-clock
// elapsed since boot, not per-service duration.
proc ui_event_started(name: string, dur_ms: int)
    g_starting_name = ""
    g_stopping_name = ""
    let elapsed = zyginit_monotonic_ms() - g_boot_start_ms
    g_done = g_done + 1
    tape_push(elapsed, paint("ok", glyph_ok()), name, "")
    if g_mode == MODE_PLAIN()
        println(fmt_plain_event(elapsed, "info", "started", name, ""))
    else
        emit_redraw(elapsed)
    end if
end ui_event_started

// dur_ms: service's own runtime (from supervisor). Reserved for future
// use (Task 6 spinner display); the tape currently shows wall-clock
// elapsed since boot, not per-service duration.
proc ui_event_failed(name: string, exit_code: int, dur_ms: int)
    g_starting_name = ""
    g_stopping_name = ""
    let elapsed = zyginit_monotonic_ms() - g_boot_start_ms
    g_done = g_done + 1
    g_failed_count = g_failed_count + 1
    if g_failed_count == 1
        g_failed_first = name
        g_failed_first_exit = exit_code
    end if
    let exit_kv = str.concat("exit=", int_to_str(exit_code))
    tape_push(elapsed, paint("fail", glyph_fail()), name, exit_kv)
    if g_mode == MODE_PLAIN()
        println(fmt_plain_event(elapsed, "err", "failed", name, exit_kv))
    else
        emit_redraw(elapsed)
    end if
end ui_event_failed

// Called when a service is transitioning to started (spinner visible).
proc ui_event_starting(name: string)
    g_starting_name = name
    let elapsed = zyginit_monotonic_ms() - g_boot_start_ms
    tape_push(elapsed, paint("warn", ui_spinner_frame(false)), name, "starting")
    if g_mode == MODE_PLAIN()
        println(fmt_plain_event(elapsed, "info", "starting", name, ""))
    else
        emit_redraw(elapsed)
    end if
end ui_event_starting

// Called when a service is transitioning to stopped (reverse spinner visible).
proc ui_event_stopping(name: string)
    g_stopping_name = name
    let elapsed = zyginit_monotonic_ms() - g_boot_start_ms
    tape_push(elapsed, paint("warn", ui_spinner_frame(true)), name, "stopping")
    if g_mode == MODE_PLAIN()
        println(fmt_plain_event(elapsed, "info", "stopping", name, ""))
    else
        emit_redraw(elapsed)
    end if
end ui_event_stopping

proc ui_init(rich_mode: int)
    g_mode = rich_mode
    g_failed = false
end ui_init

fn ui_mode(): int
    return g_mode
end ui_mode

fn ui_runlevel(): string
    return g_runlevel
end ui_runlevel

proc ui_set_mode(m: int)
    g_mode = m
end ui_set_mode

proc ui_boot_complete(stats: BootStats)
    if g_mode == MODE_PLAIN()
        println(fmt_plain_event(stats.elapsed_ms, "info", "boot_complete",
                "summary", str.concat(str.concat("online=", int_to_str(stats.online)),
                                      str.concat(" failed=", int_to_str(stats.failed)))))
        return
    end if
    // Clear screen, paint final card.
    print(str.concat(str.concat(zyginit_esc_str(), "[2J"),
          str.concat(zyginit_esc_str(), "[H")))
    let secs = stats.elapsed_ms / 1000
    let frac = (stats.elapsed_ms % 1000) / 100
    let elapsed = str.concat(str.concat(int_to_str(secs), "."),
                             str.concat(int_to_str(frac), "s"))
    let summary_count = int_to_str(stats.online + stats.failed)
    mut out = str.concat("  ", sigil())
    out = str.concat(out, str.concat(" zyginit ", str.concat(version.VERSION(), " · ")))
    out = str.concat(out, paint("frame", g_runlevel))
    out = str.concat(out, "   ")
    out = str.concat(out, paint("accent", str.concat("boot ", elapsed)))
    out = str.concat(out, "\n")
    out = str.concat(out, "  ")
    out = str.concat(out, paint("frame",
        str.concat(str.concat(summary_count, " services — "),
        str.concat(str.concat(int_to_str(stats.online), " online, "),
        str.concat(int_to_str(stats.failed), " failed")))))
    out = str.concat(out, "\n\n")
    if stats.failed == 0
        out = str.concat(out, "  ")
        out = str.concat(out, paint("ok", "all services online"))
        out = str.concat(out, "\n")
    elif stats.failed == 1
        out = str.concat(out, "  ")
        out = str.concat(out, paint("fail",
            str.concat(str.concat("failed: ", g_failed_first),
            str.concat("  exit=", int_to_str(g_failed_first_exit)))))
        out = str.concat(out, "\n")
        out = str.concat(out, "      ")
        out = str.concat(out, paint("accent",
            str.concat("→ zygctl log ", g_failed_first)))
        out = str.concat(out, paint("mute", "    to see why"))
        out = str.concat(out, "\n")
    else
        out = str.concat(out, "  ")
        out = str.concat(out, paint("fail",
            str.concat(str.concat("failed: ", int_to_str(stats.failed)), " services")))
        out = str.concat(out, "\n")
        out = str.concat(out, "      ")
        out = str.concat(out, paint("accent", "→ zygctl status"))
        out = str.concat(out, paint("mute", "    to see them"))
        out = str.concat(out, "\n")
    end if
    out = str.concat(out, "  ")
    out = str.concat(out, paint("accent", make_divider()))
    out = str.concat(out, "\n")
    // Slowest line
    let slow_n = stats.slowest_count
    if slow_n > 0
        mut slow = "slowest:"
        mut i = 0
        mut max = slow_n
        if max > 3
            max = 3
        end if
        while i < max
            slow = str.concat(slow, "  ")
            slow = str.concat(slow, stats.slowest[i])
            i = i + 1
        end while
        out = str.concat(out, "  ")
        out = str.concat(out, paint("frame", slow))
        out = str.concat(out, "\n")
    end if
    print(out)
end ui_boot_complete

proc ui_shutdown_start(reason: string)
    g_phase = "shutdown"
    g_shutdown_reason = reason
    g_runlevel = str.concat("stopping for ", reason)
    g_done = 0
    g_failed_count = 0
    g_failed_first = ""
    g_failed_first_exit = 0
    g_tape_head = 0
    g_tape_count = 0
    g_boot_start_ms = zyginit_monotonic_ms()
end ui_shutdown_start

proc ui_event_stopped(name: string, dur_ms: int)
    g_stopping_name = ""
    g_starting_name = ""
    let elapsed = zyginit_monotonic_ms() - g_boot_start_ms
    g_done = g_done + 1
    tape_push(elapsed, paint("mute", glyph_pending()), name, "")
    if g_mode == MODE_PLAIN()
        println(fmt_plain_event(elapsed, "info", "stopped", name, ""))
    else
        emit_redraw(elapsed)
    end if
end ui_event_stopped

proc ui_shutdown_complete(reason: string, elapsed_ms: int)
    if g_mode == MODE_PLAIN()
        println(fmt_plain_event(elapsed_ms, "info", "shutdown_complete",
                reason, str.concat("down=", int_to_str(g_done))))
        return
    end if
    print(str.concat(str.concat(zyginit_esc_str(), "[2J"),
          str.concat(zyginit_esc_str(), "[H")))
    let secs = elapsed_ms / 1000
    let frac = (elapsed_ms % 1000) / 100
    let elapsed = str.concat(str.concat(int_to_str(secs), "."),
                             str.concat(int_to_str(frac), "s"))
    mut out = str.concat("  ", sigil())
    out = str.concat(out, str.concat(" zyginit ", str.concat(version.VERSION(), " · ")))
    out = str.concat(out, paint("frame", str.concat(reason, " complete")))
    out = str.concat(out, "   ")
    out = str.concat(out, paint("accent", str.concat(str.concat(reason, " "), elapsed)))
    out = str.concat(out, "\n  ")
    mut stat_str = "stopped cleanly"
    if g_failed_count > 0
        stat_str = str.concat(str.concat("stopped (", int_to_str(g_failed_count)), " force-killed)")
    end if
    out = str.concat(out, paint("frame",
        str.concat(str.concat(int_to_str(g_num_svc), " services "), stat_str)))
    out = str.concat(out, "\n  ")
    out = str.concat(out, paint("accent", make_divider()))
    out = str.concat(out, "\n  ")
    out = str.concat(out, paint("mute", "invoking uadmin(A_SHUTDOWN, AD_BOOT)"))
    out = str.concat(out, "\n")
    print(out)
end ui_shutdown_complete

// Scenario dispatcher for --ui-demo. Called from main.reef.
// Returns 0 on success, 1 if the scenario name is unknown.
fn ui_demo(scenario: string): int
    if scenario == "skeleton"
        println("ui.reef skeleton ok, mode=" + int_to_str(g_mode))
        return 0
    end if
    if scenario == "plain_boot"
        println(fmt_plain_event(40, "info", "started", "root-fs", ""))
        println(fmt_plain_event(120, "info", "started", "crypto", "dur_ms=80"))
        println(fmt_plain_event(310, "info", "started", "devfs", "dur_ms=190"))
        println(fmt_plain_event(5020, "err",  "failed",  "network", "exit=1 dur_ms=4023"))
        return 0
    end if
    if str.index_of(scenario, "detect_") == 0
        g_mode = detect_rich_mode()
        println("mode=" + int_to_str(g_mode))
        return 0
    end if
    if scenario == "palette_true" or scenario == "palette_16"
        g_mode = detect_rich_mode()
        println(paint("frame",  "frame text"))
        println(paint("accent", "accent text"))
        println(paint("ok",     "ok text"))
        println(paint("warn",   "warn text"))
        println(paint("fail",   "fail text"))
        println(paint("mute",   "mute text"))
        return 0
    end if
    if scenario == "glyphs_unicode" or scenario == "glyphs_ascii"
        g_mode = detect_rich_mode()
        println(glyph_ok() + " " + glyph_starting() + " " +
                glyph_fail() + " " + glyph_pending())
        return 0
    end if
    if scenario == "sigil_rich"
        g_mode = detect_rich_mode()
        println(sigil() + " zyginit " + version.VERSION())
        return 0
    end if
    if scenario == "boot_tape_rich" or scenario == "boot_tape_ascii" or scenario == "boot_tape_plain"
        g_mode = detect_rich_mode()
        ui_boot_start(17, 8, "multi-user")
        g_boot_start_ms = 0
        let names = new [string](9)
        names[0] = "root-fs"
        names[1] = "crypto"
        names[2] = "devfs"
        names[3] = "swap"
        names[4] = "filesystem"
        names[5] = "identity"
        names[6] = "sysconfig"
        names[7] = "dlmgmtd"
        names[8] = "network"
        let elapsed_seq = new [int](9)
        elapsed_seq[0] = 40
        elapsed_seq[1] = 160
        elapsed_seq[2] = 310
        elapsed_seq[3] = 490
        elapsed_seq[4] = 1040
        elapsed_seq[5] = 1080
        elapsed_seq[6] = 1360
        elapsed_seq[7] = 1550
        elapsed_seq[8] = 5020
        mut i = 0
        while i < 8
            g_done = g_done + 1
            tape_push(elapsed_seq[i], paint("ok", glyph_ok()), names[i], "")
            i = i + 1
        end while
        g_failed_count = 1
        g_failed_first = "network"
        g_failed_first_exit = 1
        g_cur_tier = 5
        g_done = g_done + 1
        tape_push(5020, paint("fail", glyph_fail()), "network", "exit=1")
        if g_mode == MODE_PLAIN()
            let lvls = new [string](9)
            let evs = new [string](9)
            let kvs = new [string](9)
            mut j = 0
            while j < 8
                lvls[j] = "info"
                evs[j] = "started"
                kvs[j] = ""
                j = j + 1
            end while
            lvls[8] = "err"
            evs[8] = "failed"
            kvs[8] = "exit=1"
            mut k = 0
            while k < 9
                println(fmt_plain_event(elapsed_seq[k], lvls[k], evs[k], names[k], kvs[k]))
                k = k + 1
            end while
        else
            print(render_boot_screen(5020))
        end if
        return 0
    end if
    if scenario == "progress_rich" or scenario == "progress_ascii"
        g_mode = detect_rich_mode()
        ui_boot_start(17, 8, "multi-user")
        g_done = 12
        g_failed_count = 1
        print(fmt_progress_bar(g_done, g_num_svc))
        return 0
    end if
    if scenario == "progress_full"
        g_mode = detect_rich_mode()
        ui_boot_start(17, 8, "multi-user")
        g_done = 17
        print(fmt_progress_bar(g_done, g_num_svc))
        return 0
    end if
    if scenario == "spinner_forward"
        g_mode = detect_rich_mode()
        mut i = 0
        while i < 8
            g_tick = i
            print(ui_spinner_frame(false))
            i = i + 1
        end while
        println("")
        return 0
    end if
    if scenario == "spinner_reverse"
        g_mode = detect_rich_mode()
        mut i = 0
        while i < 8
            g_tick = i
            print(ui_spinner_frame(true))
            i = i + 1
        end while
        println("")
        return 0
    end if
    if scenario == "spinner_in_tape"
        g_mode = detect_rich_mode()
        ui_boot_start(17, 8, "multi-user")
        g_boot_start_ms = 0
        tape_push(40, paint("ok", glyph_ok()), "root-fs", "")
        tape_push(160, paint("ok", glyph_ok()), "crypto", "")
        tape_push(310, paint("ok", glyph_ok()), "devfs", "")
        g_done = 3
        // Manually set up the spinner state — bypass ui_event_starting to
        // avoid a host-dependent monotonic_ms() reading in the demo.
        g_starting_name = "network"
        g_tick = 0
        tape_push(2100, paint("warn", ui_spinner_frame(false)), "network", "starting")
        // Now bump tick so the live re-render shows frame index 2.
        g_tick = 2
        print(str.concat(str.concat(zyginit_esc_str(), "[2J"),
              str.concat(zyginit_esc_str(), "[H")))
        print(render_boot_screen(2100))
        return 0
    end if
    if scenario == "final_card_ok"
        g_mode = detect_rich_mode()
        ui_boot_start(17, 8, "multi-user")
        let slow = new [string](3)
        slow[0] = "dlmgmtd 1.2s"
        slow[1] = "filesystem 0.55s"
        slow[2] = "sshd 0.37s"
        let stats = BootStats{
            elapsed_ms: 8300,
            online: 17,
            failed: 0,
            slowest: slow,
            slowest_count: 3
        }
        ui_boot_complete(stats)
        return 0
    end if
    if scenario == "final_card_failed"
        g_mode = detect_rich_mode()
        ui_boot_start(17, 8, "multi-user")
        g_failed_first = "network"
        g_failed_first_exit = 1
        let slow = new [string](3)
        slow[0] = "network 5.02s"
        slow[1] = "filesystem 0.55s"
        slow[2] = "sshd 0.37s"
        let stats = BootStats{
            elapsed_ms: 8300,
            online: 16,
            failed: 1,
            slowest: slow,
            slowest_count: 3
        }
        ui_boot_complete(stats)
        return 0
    end if
    if scenario == "shutdown_mirror"
        g_mode = detect_rich_mode()
        ui_boot_start(17, 8, "multi-user")
        ui_shutdown_start("reboot")
        g_boot_start_ms = 0
        tape_push(40,  paint("mute", glyph_pending()), "sshd", "")
        tape_push(160, paint("mute", glyph_pending()), "console-login", "")
        tape_push(310, paint("mute", glyph_pending()), "cron", "")
        g_stopping_name = "syslogd"
        g_tick = 0
        tape_push(480, paint("warn", ui_spinner_frame(true)), "syslogd", "stopping")
        g_tick = 3
        g_done = 4
        g_cur_tier = 6
        print(str.concat(str.concat(zyginit_esc_str(), "[2J"),
              str.concat(zyginit_esc_str(), "[H")))
        print(render_boot_screen(480))
        return 0
    end if
    if scenario == "shutdown_final"
        g_mode = detect_rich_mode()
        ui_boot_start(17, 8, "multi-user")
        ui_shutdown_start("reboot")
        g_num_svc = 17
        g_done = 17
        ui_shutdown_complete("reboot", 2100)
        return 0
    end if
    println("ui.reef: unknown demo scenario: " + scenario)
    return 1
end ui_demo

fn int_to_str(n: int): string
    if n == 0
        return "0"
    end if

    mut value = n
    if n < 0
        value = 0 - n
    end if

    mut result = ""
    while value > 0
        let digit = value % 10
        result = str.concat(str.substring("0123456789", digit, 1), result)
        value = value / 10
    end while

    if n < 0
        result = str.concat("-", result)
    end if

    return result
end int_to_str

// ============================================================================
// Status/list rendering (used by socket command handlers)
// ============================================================================

fn pad_right(s: string, n: int): string
    let extra = n - str.length(s)
    if extra <= 0
        return s
    end if
    mut out = s
    mut i = 0
    while i < extra
        out = str.concat(out, " ")
        i = i + 1
    end while
    return out
end pad_right

end module