from io import BytesIO
from typing import Any

from PIL import Image, ImageDraw, ImageFont


WIDTH = 1200
HEIGHT = 720
FINANCE_HEIGHT = 1200
BACKGROUND = (248, 250, 252)
FOREGROUND = (17, 24, 39)
MUTED = (75, 85, 99)
GRID = (209, 213, 219)
SERIES = ((37, 99, 235), (245, 158, 11), (220, 38, 38))


def render_lifecycle_chart(chart_data: dict[str, Any]) -> bytes:
    finance = chart_data.get("finance") or {}
    image = Image.new("RGB", (WIDTH, FINANCE_HEIGHT if finance else HEIGHT), BACKGROUND)
    draw = ImageDraw.Draw(image)
    title_font = _font(36)
    section_font = _font(28)
    label_font = _font(22)
    value_font = _font(22)

    draw.text((60, 35), "Lifecycle Analysis", fill=FOREGROUND, font=title_font)
    draw.text((60, 82), str(chart_data.get("period") or ""), fill=MUTED, font=label_font)

    projects = chart_data.get("projects") or {}
    draw.text((60, 135), "Project Portfolio", fill=FOREGROUND, font=section_font)
    _stacked_bar(
        draw,
        y=190,
        values=[
            ("Unarchived", int(projects.get("unarchived") or 0), SERIES[0]),
            ("Archived", int(projects.get("archived") or 0), GRID),
        ],
        total=max(int(projects.get("total") or 0), 1),
        label_font=label_font,
        value_font=value_font,
    )

    risks = chart_data.get("risks") or {}
    draw.text((60, 295), "Current Risks", fill=FOREGROUND, font=section_font)
    _horizontal_bars(
        draw,
        y=345,
        values=[
            ("Overdue milestones", int(risks.get("overdue_milestones") or 0)),
            ("Overdue tasks", int(risks.get("overdue_tasks") or 0)),
            ("Open events", int(risks.get("open_events") or 0)),
        ],
        label_font=label_font,
        value_font=value_font,
    )

    if finance:
        cashflows = finance.get("cashflows") or {}
        receivables = finance.get("receivables") or {}
        draw.text((60, 640), "Project Finance Needs (CNY)", fill=FOREGROUND, font=section_font)
        _horizontal_bars(
            draw,
            y=695,
            values=[
                ("Confirmed inflow", int(cashflows.get("confirmed_inflow") or 0)),
                ("Confirmed outflow", int(cashflows.get("confirmed_outflow") or 0)),
                ("Pending outflow", int(cashflows.get("pending_outflow") or 0)),
                ("Overdue receivable", int(receivables.get("overdue") or 0)),
                ("Receivable due 30d", int(receivables.get("due_30d") or 0)),
            ],
            label_font=label_font,
            value_font=value_font,
        )
        top_projects = finance.get("top_projects") or []
        draw.text((650, 640), "Top 5 Funding Needs", fill=FOREGROUND, font=section_font)
        _horizontal_bars(
            draw,
            x=650,
            y=695,
            width=480,
            values=[
                (str(item.get("name") or "Project"), int(item.get("amount") or 0))
                for item in top_projects[:5]
            ],
            label_font=label_font,
            value_font=value_font,
        )

    people = chart_data.get("people") or {}
    draw.text((650, 295), "People Coverage", fill=FOREGROUND, font=section_font)
    _horizontal_bars(
        draw,
        x=650,
        y=345,
        width=480,
        values=[
            ("Active", int(people.get("active") or 0)),
            ("Needs attention", int(people.get("attention") or 0)),
            ("Attendance mapped", int(people.get("attendance_mapped") or 0)),
        ],
        label_font=label_font,
        value_font=value_font,
    )

    output = BytesIO()
    image.save(output, format="PNG", optimize=True)
    return output.getvalue()


def lifecycle_chart_alt(chart_data: dict[str, Any]) -> str:
    projects = chart_data.get("projects") or {}
    risks = chart_data.get("risks") or {}
    people = chart_data.get("people") or {}
    content = (
        f"项目总数 {projects.get('total', 0)}，未归档 {projects.get('unarchived', 0)}，"
        f"里程碑逾期 {risks.get('overdue_milestones', 0)}，任务逾期 {risks.get('overdue_tasks', 0)}，"
        f"在职人员 {people.get('active', 0)}，需关注人员 {people.get('attention', 0)}"
    )
    finance = chart_data.get("finance") or {}
    if finance:
        cashflows = finance.get("cashflows") or {}
        content += (
            f"，已确认资金流入 {cashflows.get('confirmed_inflow', 0)} 元，"
            f"待确认支出 {cashflows.get('pending_outflow', 0)} 元"
        )
    return content


def _stacked_bar(
    draw: ImageDraw.ImageDraw,
    y: int,
    values: list[tuple[str, int, tuple[int, int, int]]],
    total: int,
    label_font: ImageFont.ImageFont,
    value_font: ImageFont.ImageFont,
) -> None:
    x = 60
    width = 1070
    cursor = x
    for label, value, color in values:
        segment = round(width * value / total)
        if segment:
            draw.rectangle((cursor, y, cursor + segment, y + 42), fill=color)
        cursor += segment
    label_x = x
    for label, value, color in values:
        draw.rectangle((label_x, y + 62, label_x + 18, y + 80), fill=color)
        draw.text((label_x + 28, y + 56), f"{label} {value}", fill=FOREGROUND, font=value_font)
        label_x += 280


def _horizontal_bars(
    draw: ImageDraw.ImageDraw,
    y: int,
    values: list[tuple[str, int]],
    label_font: ImageFont.ImageFont,
    value_font: ImageFont.ImageFont,
    x: int = 60,
    width: int = 520,
) -> None:
    maximum = max((value for _, value in values), default=0) or 1
    for index, (label, value) in enumerate(values):
        row_y = y + index * 90
        draw.text((x, row_y), label, fill=MUTED, font=label_font)
        bar_y = row_y + 34
        draw.rectangle((x, bar_y, x + width, bar_y + 24), fill=GRID)
        bar_width = round(width * value / maximum)
        if bar_width:
            draw.rectangle(
                (x, bar_y, x + bar_width, bar_y + 24),
                fill=SERIES[index % len(SERIES)],
            )
        label = f"{value:,}"
        label_width = draw.textlength(label, font=value_font)
        draw.text((x + width - label_width, row_y), label, fill=FOREGROUND, font=value_font)


def _font(size: int) -> ImageFont.ImageFont:
    try:
        return ImageFont.truetype("DejaVuSans.ttf", size=size)
    except OSError:
        return ImageFont.load_default(size=size)