//! Workflow status panel rendering — agent cards with state badges.
//!
//! Flow: `draw_workflow_panel` reads `state.workflow_engine` and renders a
//! panel showing agent statuses, findings count, session counters, and
//! usage hints.
//!
//! Design: agents are shown as compact cards with state-colored badges,
//! including hive-mind nodes (named by their system-assigned designation,
//! e.g. `"Node-0-1"`).

use ratatui::layout::Rect;
use ratatui::style::{Style, Modifier};
use ratatui::text::{Line, Span};
use ratatui::widgets::{Block, Borders, Paragraph, Wrap};
use ratatui::Frame;
use super::theme::Theme;
use crate::app::workflow::engine::{AgentState, WorkflowAgent};

/// Icons for agent states.
fn state_icon(state: AgentState) -> &'static str {
    match state {
        AgentState::Idle      => "○",
        AgentState::Running   => "▶",
        AgentState::Completed => "✓",
        AgentState::Failed    => "✗",
    }
}

fn state_label(state: AgentState) -> &'static str {
    match state {
        AgentState::Idle      => "Idle",
        AgentState::Running   => "Running",
        AgentState::Completed => "Done",
        AgentState::Failed    => "Failed",
    }
}

fn state_color(state: AgentState) -> Color {
    match state {
        AgentState::Idle      => Theme::TEXT_DIM,
        AgentState::Running   => Theme::WARNING,
        AgentState::Completed => Theme::SUCCESS,
        AgentState::Failed    => Theme::ERROR,
    }
}

/// Render the workflow status panel.
#[allow(clippy::too_many_lines)]
pub fn draw_workflow_panel(frame: &mut Frame, area: Rect, state: &crate::app::state::rest::AppStateRest) {
    use ratatui::layout::{Constraint, Direction, Layout};

    let title = Span::styled(" Workflow ", Style::default().fg(Theme::PRIMARY).add_modifier(Modifier::BOLD));

    let block = Block::default()
        .borders(Borders::ALL)
        .border_style(Style::default().fg(Theme::BORDER))
        .title(title);

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

    // Split inner into header and body
    let chunks = Layout::default()
        .direction(Direction::Vertical)
        .constraints([
            Constraint::Length(3),
            Constraint::Min(4),
        ])
        .split(inner);

    // ── Header area ──────────────────────────────────────────────────────
    let mut header_lines: Vec<Line> = Vec::new();

    header_lines.push(Line::from(vec![
        Span::styled("/workflow run ", Style::default().fg(Theme::PRIMARY).add_modifier(Modifier::BOLD)),
        Span::styled("<prompt>", Style::default().fg(Theme::TEXT_DIM)),
        Span::styled("  ·  Esc to close", Style::default().fg(Theme::TEXT_DIM)),
    ]));
    header_lines.push(Line::from(vec![
        Span::styled("Status: ", Style::default().fg(Theme::TEXT_DIM)),
        if state.turn_in_flight() {
            Span::styled("● Running", Style::default().fg(Theme::WARNING).add_modifier(Modifier::BOLD))
        } else {
            Span::styled("● Idle", Style::default().fg(Theme::SUCCESS))
        },
        Span::raw("  "),
        Span::styled(
            format!("Agents: {} | Findings: {}",
                state.workflow_engine.agents.len(),
                state.workflow_engine.findings.len(),
            ),
            Style::default().fg(Theme::TEXT_DIM),
        ),
    ]));

    let header = Paragraph::new(header_lines);
    frame.render_widget(header, chunks[0]);

    // ── Body: agent cards ────────────────────────────────────────────────
    if state.workflow_engine.agents.is_empty() {
        let session_lines = build_session_lines(state);
        let placeholder = Paragraph::new(session_lines).wrap(Wrap { trim: false });
        frame.render_widget(placeholder, chunks[1]);
    } else {
        let mut card_lines: Vec<Line> = Vec::new();
        for agent in &state.workflow_engine.agents {
            let color = state_color(agent.status.state);
            let icon = state_icon(agent.status.state);
            let label = state_label(agent.status.state);

            let duration_str = match (agent.status.started_at, agent.status.completed_at) {
                (Some(s), Some(e)) => format!(" {}ms", e.saturating_sub(s)),
                (Some(_), None)    => " (running)".to_string(),
                _                  => String::new(),
            };

            // Agent card header
            card_lines.push(Line::from(vec![
                Span::styled(
                    format!(" {icon} "),
                    Style::default().fg(color).add_modifier(Modifier::BOLD),
                ),
                Span::styled(
                    format!(" {}", agent.name),
                    Style::default().fg(Theme::TEXT).add_modifier(Modifier::BOLD),
                ),
                Span::styled(
                    format!(" [{label}]"),
                    Style::default().fg(color),
                ),
                Span::styled(
                    duration_str,
                    Style::default().fg(Theme::TEXT_DIM),
                ),
            ]));

            // Agent details (progress / error)
            if let Some(ref err) = agent.status.error {
                card_lines.push(Line::from(vec![
                    Span::styled("  ⚠ ", Style::default().fg(Theme::ERROR)),
                    Span::styled(err.clone(), Style::default().fg(Theme::ERROR)),
                ]));
            } else if let Some(ref prog) = agent.status.progress {
                card_lines.push(Line::from(vec![
                    Span::styled("  ", Style::default()),
                    Span::styled(prog.clone(), Style::default().fg(Theme::TEXT_DIM).add_modifier(Modifier::ITALIC)),
                ]));
            }
        }

        let list = Paragraph::new(card_lines);
        frame.render_widget(list, chunks[1]);
    }
}

/// Build compact session info for the placeholder view.
fn build_session_lines(state: &crate::app::state::rest::AppStateRest) -> Vec<Line<'static>> {
    let mut lines: Vec<Line<'static>> = Vec::new();

    lines.push(Line::from(Span::styled(
        " No workflow running.",
        Style::default().fg(Theme::TEXT_DIM),
    )));
    lines.push(Line::from(Span::raw("")));

    if let Some(ref rt) = state.session_runtime {
        let tool_count   = rt.tool_call_results.len();
        let pending      = rt.pending_tool_queue.len();
        let bash_count   = rt.bash_jobs.len();
        let msg_count    = rt.messages.len();

        lines.push(Line::from(vec![
            Span::styled(" Messages  ", Style::default().fg(Theme::TEXT_DIM)),
            Span::styled(msg_count.to_string(), Style::default().fg(Theme::INFO).add_modifier(Modifier::BOLD)),
        ]));
        lines.push(Line::from(vec![
            Span::styled(" Tool calls", Style::default().fg(Theme::TEXT_DIM)),
            Span::styled(format!(" {tool_count}"), Style::default().fg(Theme::SUCCESS)),
        ]));
        if pending > 0 {
            lines.push(Line::from(vec![
                Span::styled(" Pending   ", Style::default().fg(Theme::TEXT_DIM)),
                Span::styled(format!(" {pending}"), Style::default().fg(Theme::WARNING)),
            ]));
        }
        if bash_count > 0 {
            lines.push(Line::from(vec![
                Span::styled(" Bash jobs ", Style::default().fg(Theme::TEXT_DIM)),
                Span::styled(format!(" {bash_count}"), Style::default().fg(Theme::WARNING)),
            ]));
        }
    } else {
        lines.push(Line::from(Span::styled(
            " (no active session)",
            Style::default().fg(Theme::TEXT_DIM),
        )));
    }

    lines.push(Line::from(Span::raw("")));
    lines.push(Line::from(Span::styled(
        " The Hive is dormant. Complex tasks will stir it.",
        Style::default().fg(Theme::TEXT_DIM).add_modifier(Modifier::ITALIC),
    )));

    lines
}

/// Render the compact Workflow widget for the persistent sidebar: one
/// line per agent (icon + name), truncated to whatever fits with a
/// trailing "+N more" hint pointing at `/workflow` for the full view.
///
/// Flow: bordered `Block` titled "Workflow" → empty state if no agents →
/// else `split_for_display` caps the list to the inner height (minus one
/// row for the hint line, if needed) → one line per visible agent.
pub fn draw_workflow_widget(frame: &mut Frame, area: Rect, state: &crate::app::state::rest::AppStateRest) {
    let block = Block::default()
        .title(Span::styled(" Workflow ", Style::default().fg(Theme::PRIMARY).add_modifier(Modifier::BOLD)))
        .borders(Borders::ALL)
        .border_style(Style::default().fg(Theme::BORDER));
    let budget = (block.inner(area).height as usize).max(1);

    let agents = &state.workflow_engine.agents;
    let lines: Vec<Line> = if agents.is_empty() {
        vec![Line::from(Span::styled(
            " No workflow running.",
            Style::default().fg(Theme::TEXT_DIM),
        ))]
    } else {
        let show_hint = agents.len() > budget;
        let item_budget = if show_hint { budget.saturating_sub(1).max(1) } else { budget };
        let (visible, hidden) = super::split_for_display(agents.as_slice(), item_budget);
        let mut lines: Vec<Line> = visible.iter().map(workflow_agent_line).collect();
        if show_hint {
            lines.push(super::overflow_hint_line(hidden, "/workflow"));
        }
        lines
    };

    let paragraph = Paragraph::new(lines).block(block);
    frame.render_widget(paragraph, area);
}

/// One compact line for a single agent: state icon + name, state-colored.
fn workflow_agent_line(agent: &WorkflowAgent) -> Line<'static> {
    let color = state_color(agent.status.state);
    let icon = state_icon(agent.status.state);
    Line::from(vec![
        Span::styled(format!(" {icon} "), Style::default().fg(color).add_modifier(Modifier::BOLD)),
        Span::styled(agent.name.clone(), Style::default().fg(Theme::TEXT)),
    ])
}

use ratatui::style::Color;