/**
 * 标题样式工具（#2001 / 模板系统 #2003）
 *
 * - snake_case TitleStyleConfig ↔ camelCase TitleSettings 互转
 * - preset 归一化预览（修复"标题"两字大小不一）
 */
import type { TitleStyleConfig } from "./types"
import type { TitleSettings } from "../../pages/generate/types"
import { TITLE_PRESETS } from "./constants"
import { DEFAULT_TITLE_SETTINGS_FULL } from "../../pages/generate/types"
import type { TitleTemplate } from "./template-types"

/** snake_case TitleStyleConfig → camelCase TitleSettings（仅覆盖已知字段） */
export function titleStyleConfigToCamel(s: Partial<TitleStyleConfig>): Partial<TitleSettings> {
  const out: Partial<TitleSettings> = {}
  if (s.font != null) out.font = s.font
  if (s.size != null) out.size = s.size
  if (s.color != null) out.color = s.color
  if (s.bold != null) out.bold = s.bold
  if (s.italic != null) out.italic = s.italic
  if (s.position != null) out.position = s.position as TitleSettings["position"]
  if (s.pos_x != null) out.posX = s.pos_x
  if (s.pos_y != null) out.posY = s.pos_y
  if (s.line_height != null) out.lineHeight = s.line_height
  if (s.margin_top != null) out.marginTop = s.margin_top
  if (s.max_chars_per_line != null) out.maxCharsPerLine = s.max_chars_per_line
  if (s.stroke != null) out.stroke = s.stroke
  if (s.stroke_width != null) out.strokeWidth = s.stroke_width
  if (s.stroke_color != null) out.strokeColor = s.stroke_color
  if (s.shadow != null) out.shadow = s.shadow
  if (s.shadow_offset_x != null) out.shadowOffsetX = s.shadow_offset_x
  if (s.shadow_offset_y != null) out.shadowOffsetY = s.shadow_offset_y
  if (s.shadow_blur != null) out.shadowBlur = s.shadow_blur
  if (s.shadow_color != null) out.shadowColor = s.shadow_color
  if (s.bg_enabled != null) out.bgEnabled = s.bg_enabled
  if (s.bg_color != null) out.bgColor = s.bg_color
  if (s.bg_padding != null) out.bgPadding = s.bg_padding
  if (s.bg_radius != null) out.bgRadius = s.bg_radius
  if (s.line_overrides != null) out.lineOverrides = s.line_overrides
  return out
}

/** camelCase TitleSettings patch → snake_case TitleStyleConfig patch */
export function camelToTitleStyleConfig(p: Partial<TitleSettings>): Partial<TitleStyleConfig> {
  const out: Partial<TitleStyleConfig> = {}
  if (p.font != null) out.font = p.font
  if (p.size != null) out.size = p.size
  if (p.color != null) out.color = p.color
  if (p.bold != null) out.bold = p.bold
  if (p.italic != null) out.italic = p.italic
  if (p.position != null) out.position = p.position as TitleStyleConfig["position"]
  if (p.posX != null) out.pos_x = p.posX
  if (p.posY != null) out.pos_y = p.posY
  if (p.lineHeight != null) out.line_height = p.lineHeight
  if (p.marginTop != null) out.margin_top = p.marginTop
  if (p.maxCharsPerLine != null) out.max_chars_per_line = p.maxCharsPerLine
  if (p.stroke != null) out.stroke = p.stroke
  if (p.strokeWidth != null) out.stroke_width = p.strokeWidth
  if (p.strokeColor != null) out.stroke_color = p.strokeColor
  if (p.shadow != null) out.shadow = p.shadow
  if (p.shadowOffsetX != null) out.shadow_offset_x = p.shadowOffsetX
  if (p.shadowOffsetY != null) out.shadow_offset_y = p.shadowOffsetY
  if (p.shadowBlur != null) out.shadow_blur = p.shadowBlur
  if (p.shadowColor != null) out.shadow_color = p.shadowColor
  if (p.bgEnabled != null) out.bg_enabled = p.bgEnabled
  if (p.bgColor != null) out.bg_color = p.bgColor
  if (p.bgPadding != null) out.bg_padding = p.bgPadding
  if (p.bgRadius != null) out.bg_radius = p.bgRadius
  if (p.lineOverrides != null) out.line_overrides = p.lineOverrides
  return out
}

/**
 * 把 preset style（snake_case）归一化为固定字号的 TitleSettings，
 * 用于"预设卡片"缩略预览——所有卡片视觉上"标题"两字大小一致，便于辨识。
 * 描边/阴影/背景padding 按 fixedSize / 原始 size 比例缩放，避免粗描边爆框。
 */
export function buildPresetPreviewSettings(
  base: TitleSettings,
  presetKey: string,
  fixedSize = 56,
): TitleSettings {
  const preset = TITLE_PRESETS.find((p) => p.key === presetKey)
  if (!preset) return base
  const origSize = preset.style.size ?? fixedSize
  const ratio = fixedSize / origSize
  const scale = (v: number | undefined, fallback: number): number =>
    v != null ? Math.round(v * ratio) : fallback
  return {
    ...base,
    ...titleStyleConfigToCamel(preset.style),
    size: fixedSize,
    strokeWidth: scale(preset.style.stroke_width, base.strokeWidth) ?? base.strokeWidth,
    shadowOffsetX: scale(preset.style.shadow_offset_x, base.shadowOffsetX) ?? base.shadowOffsetX,
    shadowOffsetY: scale(preset.style.shadow_offset_y, base.shadowOffsetY) ?? base.shadowOffsetY,
    shadowBlur: scale(preset.style.shadow_blur, base.shadowBlur) ?? base.shadowBlur,
    bgPadding: scale(preset.style.bg_padding, base.bgPadding) ?? base.bgPadding,
    lineOverrides: [],
  }
}

/**
 * 把 TitleTemplate 渲染为完整 TitleSettings（带默认值），用于卡片预览。
 * 与模板选择器中保持一致，抽出共用。
 */
export function templateToPreviewSettings(t: TitleTemplate, fixedSize = 48): TitleSettings {
  const base: TitleSettings = {
    ...DEFAULT_TITLE_SETTINGS_FULL,
    ...titleStyleConfigToCamel(t.style),
  }
  // 预览时用固定字号保证所有卡片字大小一致；描边/阴影/padding按比例缩放
  const origSize = t.style.size ?? base.size
  if (origSize && origSize !== fixedSize) {
    const ratio = fixedSize / origSize
    base.size = fixedSize
    if (base.strokeWidth != null)
      base.strokeWidth = Math.max(1, Math.round(base.strokeWidth * ratio))
    if (base.shadowOffsetX != null) base.shadowOffsetX = Math.round(base.shadowOffsetX * ratio)
    if (base.shadowOffsetY != null) base.shadowOffsetY = Math.round(base.shadowOffsetY * ratio)
    if (base.shadowBlur != null) base.shadowBlur = Math.round(base.shadowBlur * ratio)
    if (base.bgPadding != null) base.bgPadding = Math.round(base.bgPadding * ratio)
  }
  base.lineOverrides = []
  return base
}