/**
 * Static Markdown → ArkUI renderer for COMPLETE (non-streaming) chat messages.
 *
 * Parses once in aboutToAppear, builds a component tree with no timers — instant rendering.
 * Uses Span children inside Text for inline bold/italic/code/link formatting.
 *
 * 解析规则在 common/MarkdownParser.ets（已抽出，见那里）；
 * 本文件只负责把 MdBlock 渲染成 ArkUI 组件树。
 */

import { ThemePalette, DARK_PALETTE, LIGHT_PALETTE } from '../common/Constants';
import { RADIUS_SM } from '../common/Constants';
import { MdBlock, MdSpan, parseBlocks, parseInline } from '../common/MarkdownParser';

@Component
export struct StaticMarkdownView {
  @Prop content: string = '';
  @Prop isDark: boolean = true;
  private blocks: MdBlock[] = [];

  aboutToAppear(): void {
    this.blocks = parseBlocks(this.content);
  }

  private palette(): ThemePalette {
    return this.isDark ? DARK_PALETTE : LIGHT_PALETTE;
  }

  private headingSize(level: number): number {
    if (level === 1) {
      return 22;
    }
    if (level === 2) {
      return 19;
    }
    if (level === 3) {
      return 17;
    }
    if (level === 4) {
      return 15.5;
    }
    return 14;
  }

  // ── Block builders ─────────────────────────────────────────────────────────

  @Builder
  ParaBlock(text: string) {
    Column({ space: 1 }) {
      ForEach(this.splitNewlines(text), (ln: string, idx: number) => {
        // Render inline spans inside this line
        Text() {
          ForEach(parseInline(ln), (sp: MdSpan, si: number) => {
            Span(sp.text)
              .fontSize(15)
              .fontColor(sp.link === true ? this.palette().accent : sp.code === true ? this.palette().preText : this.palette().msgBubbleText)
              .fontWeight(sp.bold === true ? FontWeight.Bold : FontWeight.Normal)
              .fontStyle(sp.italic === true ? FontStyle.Italic : FontStyle.Normal)
              .fontFamily(sp.code === true ? 'monospace' : '-')
              .backgroundColor(sp.code === true ? this.palette().preBg : Color.Transparent)
              .borderRadius(3)
              .padding(sp.code === true ? { left: 3, right: 3, top: 1, bottom: 1 } : {})
              .decoration(sp.link === true ? { type: TextDecorationType.Underline } : undefined)
          }, (sp: MdSpan, si: number) => idx.toString() + '_' + si.toString())
        }
        .fontSize(15)
        .lineHeight(24)
        .fontColor(this.palette().msgBubbleText)
        .width('100%')
        .wordBreak(WordBreak.BREAK_ALL)
        .textAlign(TextAlign.Start)
      }, (ln: string, idx: number) => 'p' + idx.toString())
    }
    .width('100%')
    .margin({ top: 2, bottom: 4 })
  }

  @Builder
  HeadingBlock(block: MdBlock) {
    Text(block.text ?? '')
      .fontSize(this.headingSize(block.level ?? 1))
      .fontWeight(FontWeight.Bold)
      .fontColor(this.palette().textPrimary)
      .lineHeight(this.headingSize(block.level ?? 1) + 8)
      .width('100%')
      .margin({ top: 6, bottom: 4 })
  }

  @Builder
  CodeBlock(block: MdBlock) {
    Column() {
      Row() {
        Text(block.lang !== undefined && block.lang.length > 0 ? block.lang : 'code')
          .fontSize(10)
          .fontColor(this.palette().textMuted)
          .fontFamily('monospace')
        Blank()
      }
      .width('100%')
      .padding({ left: 10, right: 10, top: 5, bottom: 5 })
      .backgroundColor(this.palette().bgHover)

      // Code body
      Column() {
        ForEach(block.codeLines ?? [], (ln: string, idx: number) => {
          Text(ln.length > 0 ? ln : ' ')
            .fontSize(12.5)
            .lineHeight(19)
            .fontFamily('monospace')
            .fontColor(this.palette().preText)
            .width('100%')
            .textAlign(TextAlign.Start)
            .wordBreak(WordBreak.BREAK_ALL)
        }, (ln: string, idx: number) => 'c' + idx.toString())
      }
      .width('100%')
      .padding({ left: 10, right: 10, top: 8, bottom: 8 })
    }
    .width('100%')
    .borderRadius(RADIUS_SM)
    .backgroundColor(this.palette().preBg)
    .border({ width: 1, color: this.palette().kvBorder })
    .clip(true)
    .margin({ top: 4, bottom: 6 })
  }

  @Builder
  ListBlock(block: MdBlock) {
    Column({ space: 2 }) {
      ForEach(block.items ?? [], (item: string, idx: number) => {
        Row({ space: 6 }) {
          Text('•')
            .fontSize(15)
            .fontColor(this.palette().accent)
            .fontWeight(FontWeight.Bold)
            .margin({ top: 1 })
          Text() {
            ForEach(parseInline(item), (sp: MdSpan, si: number) => {
              Span(sp.text)
                .fontSize(15)
                .fontColor(sp.code === true ? this.palette().preText : this.palette().msgBubbleText)
                .fontWeight(sp.bold === true ? FontWeight.Bold : FontWeight.Normal)
                .fontStyle(sp.italic === true ? FontStyle.Italic : FontStyle.Normal)
                .fontFamily(sp.code === true ? 'monospace' : '-')
                .backgroundColor(sp.code === true ? this.palette().preBg : Color.Transparent)
                .borderRadius(3)
                .padding(sp.code === true ? { left: 3, right: 3, top: 1, bottom: 1 } : {})
            }, (sp: MdSpan, si: number) => 'li' + idx.toString() + '_' + si.toString())
          }
          .fontSize(15)
          .lineHeight(23)
          .fontColor(this.palette().msgBubbleText)
          .layoutWeight(1)
          .wordBreak(WordBreak.BREAK_ALL)
          .width('100%')
        }
        .width('100%')
        .alignItems(VerticalAlign.Top)
      }, (item: string, idx: number) => idx.toString())
    }
    .width('100%')
    .margin({ top: 2, bottom: 4 })
  }

  @Builder
  OlBlock(block: MdBlock) {
    Column({ space: 2 }) {
      ForEach(block.items ?? [], (item: string, idx: number) => {
        Row({ space: 6 }) {
          Text((idx + 1).toString() + '.')
            .fontSize(15)
            .fontColor(this.palette().accent)
            .fontWeight(FontWeight.Medium)
            .margin({ top: 1 })
          Text() {
            ForEach(parseInline(item), (sp: MdSpan, si: number) => {
              Span(sp.text)
                .fontSize(15)
                .fontColor(sp.code === true ? this.palette().preText : this.palette().msgBubbleText)
                .fontWeight(sp.bold === true ? FontWeight.Bold : FontWeight.Normal)
                .fontStyle(sp.italic === true ? FontStyle.Italic : FontStyle.Normal)
                .fontFamily(sp.code === true ? 'monospace' : '-')
                .backgroundColor(sp.code === true ? this.palette().preBg : Color.Transparent)
                .borderRadius(3)
                .padding(sp.code === true ? { left: 3, right: 3, top: 1, bottom: 1 } : {})
            }, (sp: MdSpan, si: number) => 'oli' + idx.toString() + '_' + si.toString())
          }
          .fontSize(15)
          .lineHeight(23)
          .fontColor(this.palette().msgBubbleText)
          .layoutWeight(1)
          .wordBreak(WordBreak.BREAK_ALL)
          .width('100%')
        }
        .width('100%')
        .alignItems(VerticalAlign.Top)
      }, (item: string, idx: number) => idx.toString())
    }
    .width('100%')
    .margin({ top: 2, bottom: 4 })
  }

  @Builder
  BlockquoteBlock(text: string) {
    Column() {
      ForEach(this.splitNewlines(text), (ln: string, idx: number) => {
        Text() {
          ForEach(parseInline(ln), (sp: MdSpan, si: number) => {
            Span(sp.text)
              .fontSize(14)
              .fontColor(this.palette().textTertiary)
              .fontStyle(sp.italic === true ? FontStyle.Italic : FontStyle.Normal)
              .fontWeight(sp.bold === true ? FontWeight.Bold : FontWeight.Normal)
          }, (sp: MdSpan, si: number) => 'bq' + idx.toString() + '_' + si.toString())
        }
        .fontSize(14)
        .lineHeight(22)
        .width('100%')
        .wordBreak(WordBreak.BREAK_ALL)
      }, (ln: string, idx: number) => 'bq' + idx.toString())
    }
    .width('100%')
    .padding({ left: 10, right: 10, top: 6, bottom: 6 })
    .margin({ top: 3, bottom: 5 })
    .borderRadius({ topLeft: 0, topRight: 6, bottomRight: 6, bottomLeft: 0 })
    .backgroundColor(this.palette().bgHover)
    .border({
      width: { left: 3, top: 0, right: 0, bottom: 0 },
      color: { left: this.palette().accent, top: Color.Transparent, right: Color.Transparent, bottom: Color.Transparent },
    })
  }

  @Builder
  HrBlock() {
    Row()
      .width('100%')
      .height(1)
      .backgroundColor(this.palette().kvBorder)
      .margin({ top: 6, bottom: 6 })
  }

  @Builder
  TableBlock(block: MdBlock) {
    Column() {
      // Header
      Row() {
        ForEach(block.headers ?? [], (h: string, hi: number) => {
          Text() {
            ForEach(parseInline(h), (sp: MdSpan, si: number) => {
              Span(sp.text)
                .fontSize(12.5)
                .fontWeight(FontWeight.Medium)
                .fontColor(this.palette().textPrimary)
            }, (sp: MdSpan, si: number) => 'th' + hi.toString() + '_' + si.toString())
          }
          .fontSize(12.5)
          .fontColor(this.palette().textPrimary)
          .layoutWeight(1)
          .padding({ left: 6, right: 6, top: 5, bottom: 5 })
        }, (h: string, hi: number) => 'th' + hi.toString())
      }
      .width('100%')
      .backgroundColor(this.palette().bgHover)

      // Body
      ForEach(block.rows ?? [], (row: string[], ri: number) => {
        Row() {
          ForEach(row, (cell: string, ci: number) => {
            Text() {
              ForEach(parseInline(cell), (sp: MdSpan, si: number) => {
                Span(sp.text)
                  .fontSize(12.5)
                  .fontColor(this.palette().msgBubbleText)
                  .fontFamily(sp.code === true ? 'monospace' : '-')
                  .backgroundColor(sp.code === true ? this.palette().preBg : Color.Transparent)
              }, (sp: MdSpan, si: number) => 'td' + ri.toString() + '_' + ci.toString() + '_' + si.toString())
            }
            .fontSize(12.5)
            .fontColor(this.palette().msgBubbleText)
            .layoutWeight(1)
            .padding({ left: 6, right: 6, top: 4, bottom: 4 })
            .wordBreak(WordBreak.BREAK_ALL)
            .width('100%')
          }, (cell: string, ci: number) => 'td' + ri.toString() + '_' + ci.toString())
        }
        .width('100%')
      }, (row: string[], ri: number) => 'tr' + ri.toString())
    }
    .width('100%')
    .borderRadius(RADIUS_SM)
    .border({ width: 1, color: this.palette().kvBorder })
    .clip(true)
    .margin({ top: 4, bottom: 6 })
  }

  // ── Helpers ────────────────────────────────────────────────────────────────

  private splitNewlines(text: string): string[] {
    if (text.length === 0) {
      return [];
    }
    return text.split('\n');
  }

  // ── Build ──────────────────────────────────────────────────────────────────

  build() {
    Column() {
      ForEach(this.blocks, (b: MdBlock, idx: number) => {
        if (b.type === 'code') {
          this.CodeBlock(b)
        } else if (b.type === 'heading') {
          this.HeadingBlock(b)
        } else if (b.type === 'list') {
          this.ListBlock(b)
        } else if (b.type === 'ol') {
          this.OlBlock(b)
        } else if (b.type === 'blockquote') {
          this.BlockquoteBlock(b.text ?? '')
        } else if (b.type === 'hr') {
          this.HrBlock()
        } else if (b.type === 'table') {
          this.TableBlock(b)
        } else {
          this.ParaBlock(b.text ?? '')
        }
      }, (b: MdBlock, idx: number) => idx.toString() + b.type + ((b.text ?? '').substring(0, 12)))
    }
    .width('100%')
    .alignItems(HorizontalAlign.Start)
  }
}