"""
Premium Gantt-style timeline visualization using Plotly.

Features:
    - Glassmorphic dark theme matching the UI
    - Color coding by priority and status
    - Conflict highlighting with red borders
    - Custom HH:MM time axis
    - Inbox summary bar chart
"""

import plotly.graph_objects as go
from typing import List, Dict


# ─── Premium Color Palette ───────────────────────────────────────────────────

PRIORITY_COLORS = {
    "high": "#f87171",
    "medium": "#fbbf24",
    "low": "#60a5fa",
}

STATUS_COLORS = {
    "completed": "#34d399",
    "scheduled": "#a78bfa",
    "pending": "#fbbf24",
    "missed": "#f87171",
    "deferred": "#94a3b8",
    "rejected": "#6b7280",
}

TYPE_LABELS = {
    "meeting": "Meeting",
    "work": "Work",
    "personal": "Personal",
}

PLOT_BG = "#0f1629"
PAPER_BG = "#0a0f1e"
GRID_COLOR = "rgba(148, 163, 184, 0.08)"
TEXT_COLOR = "#c7d2fe"
SUBTLE_TEXT = "#64748b"


def _time_to_minutes(time_str: str) -> int:
    h, m = map(int, time_str.split(":"))
    return h * 60 + m


def _minutes_to_time(minutes: int) -> str:
    return f"{minutes // 60:02d}:{minutes % 60:02d}"


def _add_minutes(time_str: str, minutes: int) -> str:
    return _minutes_to_time(_time_to_minutes(time_str) + minutes)


# ─── Main Timeline ───────────────────────────────────────────────────────────

def create_timeline(
    tasks: List[Dict],
    current_time: str = "08:00",
    title: str = "Executive Schedule Timeline",
    show_conflicts: bool = True,
) -> go.Figure:
    """Create a premium Gantt-style timeline."""

    fig = go.Figure()

    if not tasks:
        fig.add_annotation(
            text="No tasks scheduled yet",
            xref="paper", yref="paper",
            x=0.5, y=0.5, showarrow=False,
            font=dict(size=18, color=SUBTLE_TEXT, family="Inter"),
        )
        fig.update_layout(
            template="plotly_dark",
            paper_bgcolor=PAPER_BG,
            plot_bgcolor=PLOT_BG,
            title=dict(text=title, font=dict(size=16, color=TEXT_COLOR, family="Inter")),
            height=200,
        )
        return fig

    sorted_tasks = sorted(tasks, key=lambda t: t.get("time", "08:00"))

    conflict_pairs = set()
    if show_conflicts:
        conflict_pairs = _find_conflict_pairs(sorted_tasks)

    for idx, task in enumerate(sorted_tasks):
        start_time = task.get("time", "08:00")
        duration = task.get("duration", 30)
        end_time = _add_minutes(start_time, duration)
        status = task.get("status", "pending")
        priority = task.get("priority", "medium")
        task_type = task.get("type", "work")
        task_title = task.get("title", f"Task {task.get('id', idx)}")
        task_id = task.get("id", idx)

        color = STATUS_COLORS.get(status, PRIORITY_COLORS.get(priority, "#60a5fa"))
        is_conflicted = any(task_id in pair for pair in conflict_pairs)
        border_color = "#ef4444" if is_conflicted else "rgba(255,255,255,0.1)"
        border_width = 3 if is_conflicted else 1

        type_label = TYPE_LABELS.get(task_type, "Task")
        label = f"{task_title}"

        conflict_text = (
            "<span style='color:#ef4444'><b>CONFLICT DETECTED</b></span>"
            if is_conflicted
            else "<span style='color:#34d399'>No conflict</span>"
        )

        hover_text = (
            f"<b>{task_title}</b><br>"
            f"<span style='color:#94a3b8'>Time:</span> {start_time} - {end_time} ({duration}min)<br>"
            f"<span style='color:#94a3b8'>Priority:</span> {priority.upper()}<br>"
            f"<span style='color:#94a3b8'>Status:</span> {status.upper()}<br>"
            f"<span style='color:#94a3b8'>Type:</span> {type_label}<br>"
            f"{conflict_text}"
        )

        start_mins = _time_to_minutes(start_time)

        fig.add_trace(go.Bar(
            x=[duration],
            y=[label],
            base=[start_mins],
            orientation="h",
            marker=dict(
                color=color,
                line=dict(color=border_color, width=border_width),
                opacity=0.88 if status != "missed" else 0.35,
                cornerradius=6,
            ),
            hovertext=hover_text,
            hoverinfo="text",
            showlegend=False,
            text=f"  {start_time} - {end_time}  ",
            textposition="inside",
            textfont=dict(color="white", size=11, family="Inter"),
        ))

    # "Now" indicator
    now_mins = _time_to_minutes(current_time)
    fig.add_shape(
        type="line",
        x0=now_mins, x1=now_mins,
        y0=-0.5, y1=len(sorted_tasks) - 0.5,
        line=dict(color="#818cf8", width=2, dash="dot"),
    )
    fig.add_annotation(
        x=now_mins, y=-0.6,
        text=f"NOW {current_time}",
        showarrow=False,
        font=dict(color="#818cf8", size=11, family="Inter", weight="bold" if hasattr(dict, '__call__') else None),
        bgcolor="rgba(129,140,248,0.1)",
        bordercolor="rgba(129,140,248,0.3)",
        borderwidth=1,
        borderpad=4,
    )

    # Time axis
    tick_vals = list(range(480, 1081, 30))  # 08:00 to 18:00
    tick_labels = [_minutes_to_time(m) for m in tick_vals]

    fig.update_layout(
        title=dict(
            text=title,
            font=dict(size=16, color=TEXT_COLOR, family="Inter"),
            x=0.01,
        ),
        xaxis=dict(
            tickvals=tick_vals,
            ticktext=tick_labels,
            range=[460, 1100],
            gridcolor=GRID_COLOR,
            tickfont=dict(color=SUBTLE_TEXT, size=10, family="Inter"),
            title=None,
        ),
        yaxis=dict(
            autorange="reversed",
            gridcolor=GRID_COLOR,
            tickfont=dict(color=TEXT_COLOR, size=11, family="Inter"),
            title=None,
        ),
        template="plotly_dark",
        paper_bgcolor=PAPER_BG,
        plot_bgcolor=PLOT_BG,
        height=max(280, len(sorted_tasks) * 48 + 120),
        margin=dict(l=220, r=40, t=60, b=50),
        barmode="overlay",
        hoverlabel=dict(
            bgcolor="#1e293b",
            bordercolor="rgba(255,255,255,0.1)",
            font=dict(color=TEXT_COLOR, size=12, family="Inter"),
        ),
    )

    # Status legend
    for status, color in STATUS_COLORS.items():
        fig.add_trace(go.Bar(
            x=[0], y=["_"],
            marker=dict(color=color),
            name=status.capitalize(),
            showlegend=True,
            visible="legendonly",
        ))

    # Conflict warning
    if conflict_pairs:
        fig.add_annotation(
            text=f"  {len(conflict_pairs)} conflict(s) detected  ",
            xref="paper", yref="paper",
            x=0.99, y=1.06,
            xanchor="right",
            showarrow=False,
            font=dict(size=12, color="#fca5a5", family="Inter"),
            bgcolor="rgba(239,68,68,0.12)",
            bordercolor="rgba(239,68,68,0.3)",
            borderwidth=1,
            borderpad=6,
        )

    fig.update_layout(
        legend=dict(
            orientation="h",
            yanchor="bottom",
            y=-0.2,
            xanchor="center",
            x=0.5,
            font=dict(size=10, color=SUBTLE_TEXT, family="Inter"),
            bgcolor="rgba(0,0,0,0)",
        )
    )

    return fig


def _find_conflict_pairs(tasks: List[Dict]) -> set:
    conflicts = set()
    for i, t1 in enumerate(tasks):
        for t2 in tasks[i + 1:]:
            s1 = _time_to_minutes(t1.get("time", "08:00"))
            e1 = s1 + t1.get("duration", 30)
            s2 = _time_to_minutes(t2.get("time", "08:00"))
            e2 = s2 + t2.get("duration", 30)
            if s1 < e2 and s2 < e1:
                conflicts.add((t1.get("id", i), t2.get("id", i + 1)))
    return conflicts


# ─── Inbox Summary Chart ────────────────────────────────────────────────────

def create_inbox_summary(inbox: List[Dict]) -> go.Figure:
    """Create a premium inbox status chart."""

    fig = go.Figure()

    if not inbox:
        fig.add_annotation(
            text="No messages",
            xref="paper", yref="paper",
            x=0.5, y=0.5, showarrow=False,
            font=dict(size=16, color=SUBTLE_TEXT, family="Inter"),
        )
        fig.update_layout(
            template="plotly_dark",
            paper_bgcolor=PAPER_BG,
            plot_bgcolor=PLOT_BG,
            height=280,
        )
        return fig

    total = len(inbox)
    replied = sum(1 for m in inbox if m.get("replied", False))
    urgent = sum(1 for m in inbox if m.get("urgency") == "high")
    urgent_replied = sum(
        1 for m in inbox
        if m.get("urgency") == "high" and m.get("replied", False)
    )

    categories = ["Total", "Replied", "Urgent", "Urgent\nReplied"]
    values = [total, replied, urgent, urgent_replied]
    colors = ["#818cf8", "#34d399", "#f87171", "#fbbf24"]

    fig.add_trace(go.Bar(
        x=categories,
        y=values,
        marker=dict(
            color=colors,
            line=dict(color="rgba(255,255,255,0.05)", width=1),
            cornerradius=8,
            opacity=0.85,
        ),
        text=values,
        textposition="outside",
        textfont=dict(size=16, color=TEXT_COLOR, family="Inter", weight=700),
    ))

    fig.update_layout(
        title=dict(
            text="Inbox Status",
            font=dict(size=14, color=TEXT_COLOR, family="Inter"),
            x=0.01,
        ),
        template="plotly_dark",
        paper_bgcolor=PAPER_BG,
        plot_bgcolor=PLOT_BG,
        height=280,
        yaxis=dict(
            gridcolor=GRID_COLOR,
            tickfont=dict(color=SUBTLE_TEXT, size=10, family="Inter"),
            title=None,
        ),
        xaxis=dict(
            tickfont=dict(color=TEXT_COLOR, size=11, family="Inter"),
            title=None,
        ),
        margin=dict(l=40, r=20, t=50, b=40),
        hoverlabel=dict(
            bgcolor="#1e293b",
            font=dict(color=TEXT_COLOR, family="Inter"),
        ),
    )

    return fig