"""参数化 SVG 渲染: traits + age + stage + sick + mood → 蛐蛐形象.

设计原则: 零依赖、零成本、演化连续可见。
映射(可随时调,但保持单调直觉):
  勇 brave   → 触须张角/前肢姿态(越勇越张扬)
  萌 cute    → 眼睛大小/身体圆润度
  怨 grudge  → 体色向紫黑偏移/眉角下压
  智 wit     → 额头花纹复杂度(条纹数)
  馋 glutton → 肚子大小
  stage      → 整体尺寸 + 翅膀层数(蜕皮=大变样)
  sick       → 整体降饱和 + 绿色病气 + 眼睛变 X
"""
from __future__ import annotations

from traits import TRAIT_KEYS, molt_stage


def _lerp(a: float, b: float, t: float) -> float:
    return a + (b - a) * t


def _color(traits: dict, sick: bool) -> tuple[str, str]:
    """主体色: 健康=暖棕→怨气高偏紫黑; 生病=灰绿."""
    g = traits.get("grudge", 0.5)
    if sick:
        return "#7a8a6a", "#5a6a4a"
    r = int(_lerp(150, 90, g))
    gr = int(_lerp(95, 60, g))
    b = int(_lerp(60, 110, g))
    return f"rgb({r},{gr},{b})", f"rgb({max(r-40,0)},{max(gr-30,0)},{max(b-20,0)})"


def render_svg(traits: dict, feed_count: int = 0, sick: bool = False,
               mood: str = "calm", width: int = 360, height: int = 280) -> str:
    """返回完整 <svg> 字符串."""
    t = {k: float(traits.get(k, 0.5)) for k in TRAIT_KEYS}
    stage = molt_stage(feed_count)
    scale = _lerp(0.7, 1.15, min(stage, 3) / 3)
    body_fill, body_dark = _color(t, sick)

    cx, cy = width / 2, height / 2 + 20
    belly = _lerp(34, 52, t["glutton"]) * scale          # 馋→肚子
    body_ry = _lerp(belly * 0.78, belly * 0.95, t["cute"])  # 萌→圆润
    eye_r = _lerp(4.5, 9.5, t["cute"]) * scale            # 萌→大眼
    ant_spread = _lerp(8, 42, t["brave"])                 # 勇→触须张角(度)
    ant_len = _lerp(55, 85, t["brave"]) * scale
    stripes = 1 + int(round(t["wit"] * 4))                # 智→花纹条数
    brow_drop = _lerp(-3, 5, t["grudge"])                 # 怨→眉角下压

    head_cx = cx - belly * 0.95
    head_cy = cy - body_ry * 0.45
    head_r = _lerp(16, 22, t["cute"]) * scale

    parts: list[str] = []
    parts.append(
        f'<svg xmlns="http://www.w3.org/2000/svg" width="{width}" height="{height}" '
        f'viewBox="0 0 {width} {height}">'
    )
    # 地面
    parts.append(f'<ellipse cx="{cx}" cy="{cy + body_ry + 14}" rx="{belly * 1.6}" ry="10" fill="#00000014"/>')
    # 后腿(蛐蛐标志性大跳腿)
    leg = belly * 1.25
    parts.append(
        f'<path d="M {cx + belly * 0.5} {cy} q {leg * 0.55} {-leg * 0.7} {leg * 0.32} {leg * 0.05} '
        f'l {-leg * 0.12} {leg * 0.62}" stroke="{body_dark}" stroke-width="{5 * scale}" fill="none" stroke-linecap="round"/>'
    )
    # 身体
    parts.append(f'<ellipse cx="{cx}" cy="{cy}" rx="{belly}" ry="{body_ry}" fill="{body_fill}"/>')
    # 翅膀层数 = stage+1(蜕皮可见)
    for i in range(stage + 1):
        wy = cy - body_ry * 0.55 - i * 4 * scale
        parts.append(
            f'<ellipse cx="{cx + 6}" cy="{wy}" rx="{belly * 0.85}" ry="{body_ry * 0.45}" '
            f'fill="{body_dark}" opacity="{0.55 - i * 0.12}"/>'
        )
    # 智力花纹
    for i in range(stripes):
        sx = cx - belly * 0.4 + i * (belly * 0.8 / max(stripes - 1, 1))
        parts.append(
            f'<line x1="{sx}" y1="{cy - body_ry * 0.25}" x2="{sx}" y2="{cy + body_ry * 0.35}" '
            f'stroke="{body_dark}" stroke-width="{2 * scale}" opacity="0.6"/>'
        )
    # 头
    parts.append(f'<circle cx="{head_cx}" cy="{head_cy}" r="{head_r}" fill="{body_fill}"/>')
    # 触须(勇→张角)
    for sign in (-1, 1):
        ang = (-90 + sign * ant_spread) * 3.14159 / 180
        ex = head_cx + ant_len * 1.0 * __import__("math").cos(ang) * (0.6 if sign < 0 else 0.8)
        ey = head_cy + ant_len * __import__("math").sin(ang)
        mx = head_cx + sign * 10
        my = head_cy - ant_len * 0.6
        parts.append(
            f'<path d="M {head_cx} {head_cy - head_r * 0.7} Q {mx} {my} {ex} {ey}" '
            f'stroke="{body_dark}" stroke-width="{2.2 * scale}" fill="none" stroke-linecap="round"/>'
        )
    # 眼睛 / 病眼
    eye_x, eye_y = head_cx - head_r * 0.25, head_cy - head_r * 0.15
    if sick:
        s = eye_r * 0.8
        parts.append(
            f'<g stroke="#3a3a3a" stroke-width="2.4" stroke-linecap="round">'
            f'<line x1="{eye_x - s}" y1="{eye_y - s}" x2="{eye_x + s}" y2="{eye_y + s}"/>'
            f'<line x1="{eye_x - s}" y1="{eye_y + s}" x2="{eye_x + s}" y2="{eye_y - s}"/></g>'
        )
        # 病气泡
        parts.append(f'<circle cx="{head_cx - head_r * 1.4}" cy="{head_cy - head_r}" r="5" fill="#9ab87a" opacity="0.8"/>')
    else:
        parts.append(f'<circle cx="{eye_x}" cy="{eye_y}" r="{eye_r}" fill="#241a12"/>')
        parts.append(f'<circle cx="{eye_x + eye_r * 0.3}" cy="{eye_y - eye_r * 0.3}" r="{eye_r * 0.3}" fill="#fff"/>')
    # 怨气眉
    parts.append(
        f'<line x1="{eye_x - eye_r * 1.4}" y1="{eye_y - eye_r * 1.6 + brow_drop}" '
        f'x2="{eye_x + eye_r * 1.2}" y2="{eye_y - eye_r * 1.6 - brow_drop}" '
        f'stroke="#241a12" stroke-width="2.6" stroke-linecap="round"/>'
    )
    # 嘴(mood 简单弯曲)
    smile = {"happy": 6, "excited": 7, "loved": 6, "content": 4, "calm": 1,
             "sad": -5, "angry": -6, "hurt": -6, "disgusted": -4}.get(mood, 1)
    parts.append(
        f'<path d="M {head_cx - 7} {head_cy + head_r * 0.45} q 7 {smile} 14 0" '
        f'stroke="#241a12" stroke-width="2.2" fill="none" stroke-linecap="round"/>'
    )
    parts.append("</svg>")
    return "".join(parts)


def svg_params(traits: dict, feed_count: int, sick: bool, mood: str) -> dict:
    """快照里存的渲染参数(回放史料)."""
    return {
        "traits": {k: round(float(traits.get(k, 0.5)), 4) for k in TRAIT_KEYS},
        "stage": molt_stage(feed_count),
        "sick": bool(sick),
        "mood": mood,
        "feed_count": feed_count,
    }