#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Deep Research 中文 PDF 报告模板（ReportLab 基础版）

用法：
    python3 report-template.py \
        --input  projects/<slug>/phase4/final.md \
        --manifest projects/<slug>/manifest.json \
        --output projects/<slug>/phase4/final.pdf \
        --fonts-dir .opencode/templates/fonts

依赖：
    pip install reportlab markdown-it-py

设计原则：
1. 字体集中注册，样式集中管理（StyleSheet），避免字号不一
2. 思源宋 = 正文；思源黑 = 标题/UI；霞鹜文楷 = 引文/摘要
3. Markdown → ReportLab Flowables，保留结构化信息
4. 基础版支持：封面 / 目录 / 正文（h1-h3 / 段落 / 列表 / 引用 / 表格 / 图片）/ 参考文献
5. 基础版暂不支持：PDF 书签、交叉引用、附录自动生成（后续补齐）
"""

from __future__ import annotations

import argparse
import json
import re
import sys
from dataclasses import dataclass
from pathlib import Path
from typing import List, Optional, Tuple

try:
    from reportlab.lib import colors
    from reportlab.lib.enums import TA_CENTER, TA_JUSTIFY, TA_LEFT, TA_RIGHT
    from reportlab.lib.pagesizes import A4
    from reportlab.lib.styles import ParagraphStyle, StyleSheet1
    from reportlab.lib.units import cm, mm
    from reportlab.pdfbase import pdfmetrics
    from reportlab.pdfbase.ttfonts import TTFont
    from reportlab.platypus import (
        BaseDocTemplate,
        Frame,
        Image,
        NextPageTemplate,
        PageBreak,
        PageTemplate,
        Paragraph,
        Spacer,
        Table,
        TableStyle,
    )
except ImportError:
    print("❌ 缺少依赖：pip install reportlab", file=sys.stderr)
    sys.exit(1)


# ============================================================
# 字体注册
# ============================================================

FONT_MAP = {
    # 逻辑名 -> 文件名（优先 ttf/ 子目录的 TrueType 转换版，兼容 ReportLab）
    "SrcSerif":        "ttf/SourceHanSerifSC-Regular.ttf",
    "SrcSerif-Bold":   "ttf/SourceHanSerifSC-Bold.ttf",
    "SrcSans-Light":   "ttf/SourceHanSansSC-Light.ttf",
    "SrcSans-Medium":  "ttf/SourceHanSansSC-Medium.ttf",
    "SrcSans-Bold":    "ttf/SourceHanSansSC-Bold.ttf",
    "SrcSans-Heavy":   "ttf/SourceHanSansSC-Heavy.ttf",
    "Kai":             "LXGWWenKai-Regular.ttf",
}


def register_fonts(fonts_dir: Path) -> None:
    """注册所有中文字体。失败则 exit(1)。"""
    missing = []
    for logical, filename in FONT_MAP.items():
        font_path = fonts_dir / filename
        if not font_path.exists():
            missing.append(str(font_path))
            continue
        try:
            pdfmetrics.registerFont(TTFont(logical, str(font_path)))
        except Exception as e:
            print(f"❌ 字体注册失败：{logical} ({font_path}): {e}", file=sys.stderr)
            sys.exit(1)

    if missing:
        print("❌ 缺少字体文件：", file=sys.stderr)
        for m in missing:
            print(f"   - {m}", file=sys.stderr)
        print("\n请运行：bash .opencode/templates/fonts/download-fonts.sh", file=sys.stderr)
        sys.exit(1)

    # 注册字体族（粗体自动映射）
    pdfmetrics.registerFontFamily(
        "SrcSerif",
        normal="SrcSerif",
        bold="SrcSerif-Bold",
        italic="SrcSerif",
        boldItalic="SrcSerif-Bold",
    )
    pdfmetrics.registerFontFamily(
        "SrcSans",
        normal="SrcSans-Medium",
        bold="SrcSans-Bold",
        italic="SrcSans-Medium",
        boldItalic="SrcSans-Bold",
    )


# ============================================================
# 样式表（集中管理）
# ============================================================

def build_styles() -> StyleSheet1:
    """构建所有段落样式。字号、行高在此唯一定义。"""
    ss = StyleSheet1()

    # 正文
    ss.add(ParagraphStyle(
        name="body",
        fontName="SrcSerif",
        fontSize=10.5,
        leading=18,
        alignment=TA_JUSTIFY,
        firstLineIndent=21,  # 首行缩进 2 字符
        spaceBefore=2,
        spaceAfter=2,
        textColor=colors.HexColor("#1a1a1a"),
        wordWrap="CJK",
    ))

    # 一级标题（章）
    ss.add(ParagraphStyle(
        name="h1",
        fontName="SrcSans-Bold",
        fontSize=18,
        leading=28,
        alignment=TA_LEFT,
        spaceBefore=20,
        spaceAfter=12,
        textColor=colors.HexColor("#1e3a8a"),
        keepWithNext=True,
        wordWrap="CJK",
    ))

    # 二级标题（section）
    ss.add(ParagraphStyle(
        name="h2",
        fontName="SrcSans-Bold",
        fontSize=14,
        leading=22,
        alignment=TA_LEFT,
        spaceBefore=14,
        spaceAfter=8,
        textColor=colors.HexColor("#1e40af"),
        keepWithNext=True,
        wordWrap="CJK",
    ))

    # 三级标题（sub-section）
    ss.add(ParagraphStyle(
        name="h3",
        fontName="SrcSans-Medium",
        fontSize=12,
        leading=18,
        alignment=TA_LEFT,
        spaceBefore=10,
        spaceAfter=6,
        textColor=colors.HexColor("#374151"),
        keepWithNext=True,
        wordWrap="CJK",
    ))

    # 引文 / 摘要（霞鹜文楷）
    ss.add(ParagraphStyle(
        name="quote",
        fontName="Kai",
        fontSize=10.5,
        leading=18,
        alignment=TA_JUSTIFY,
        leftIndent=20,
        rightIndent=20,
        spaceBefore=6,
        spaceAfter=6,
        textColor=colors.HexColor("#4b5563"),
        borderWidth=0,
        borderPadding=8,
        borderColor=colors.HexColor("#d1d5db"),
        backColor=colors.HexColor("#f9fafb"),
        wordWrap="CJK",
    ))

    # 图表标题
    ss.add(ParagraphStyle(
        name="caption",
        fontName="SrcSans-Medium",
        fontSize=9,
        leading=13,
        alignment=TA_CENTER,
        spaceBefore=4,
        spaceAfter=10,
        textColor=colors.HexColor("#6b7280"),
        wordWrap="CJK",
    ))

    # 脚注 / 参考文献
    ss.add(ParagraphStyle(
        name="footnote",
        fontName="SrcSerif",
        fontSize=9,
        leading=13,
        alignment=TA_JUSTIFY,
        leftIndent=20,
        firstLineIndent=-20,  # 悬挂缩进
        spaceAfter=4,
        textColor=colors.HexColor("#374151"),
        wordWrap="CJK",
    ))

    # 页眉页脚
    ss.add(ParagraphStyle(
        name="header-footer",
        fontName="SrcSans-Light",
        fontSize=8,
        leading=12,
        alignment=TA_CENTER,
        textColor=colors.HexColor("#9ca3af"),
    ))

    # 封面大标题
    ss.add(ParagraphStyle(
        name="cover-title",
        fontName="SrcSans-Heavy",
        fontSize=32,
        leading=42,
        alignment=TA_CENTER,
        spaceBefore=12,
        spaceAfter=12,
        textColor=colors.HexColor("#0f172a"),
        wordWrap="CJK",
    ))

    ss.add(ParagraphStyle(
        name="cover-subtitle",
        fontName="SrcSans-Medium",
        fontSize=16,
        leading=24,
        alignment=TA_CENTER,
        spaceBefore=8,
        spaceAfter=30,
        textColor=colors.HexColor("#475569"),
        wordWrap="CJK",
    ))

    ss.add(ParagraphStyle(
        name="cover-meta",
        fontName="SrcSerif",
        fontSize=11,
        leading=18,
        alignment=TA_CENTER,
        textColor=colors.HexColor("#334155"),
        wordWrap="CJK",
    ))

    # 列表
    ss.add(ParagraphStyle(
        name="bullet",
        parent=ss["body"],
        firstLineIndent=0,
        leftIndent=20,
        bulletIndent=6,
    ))

    return ss


# ============================================================
# Markdown 轻量解析（基础版）
# ============================================================

@dataclass
class Block:
    kind: str       # h1 / h2 / h3 / p / quote / bullet / image / table / hr
    content: str    # 原始 Markdown 内容
    meta: Optional[dict] = None


def parse_markdown(md_text: str) -> List[Block]:
    """
    极简 Markdown 解析器，输出扁平 Block 列表。
    不支持嵌套结构，复杂情况后续可接 markdown-it-py。
    """
    blocks: List[Block] = []
    lines = md_text.split("\n")
    i = 0
    while i < len(lines):
        line = lines[i]
        stripped = line.strip()

        # 空行
        if not stripped:
            i += 1
            continue

        # 水平线 / 分页
        if stripped in ("---", "***", "___"):
            blocks.append(Block(kind="hr", content=""))
            i += 1
            continue

        # 标题
        if stripped.startswith("#"):
            m = re.match(r"^(#{1,6})\s+(.+)$", stripped)
            if m:
                level = min(len(m.group(1)), 3)  # h4+ 降级为 h3
                blocks.append(Block(kind=f"h{level}", content=m.group(2).strip()))
                i += 1
                continue

        # 图片
        m = re.match(r"^!\[([^\]]*)\]\(([^)]+)\)", stripped)
        if m:
            blocks.append(Block(
                kind="image",
                content=m.group(2),
                meta={"caption": m.group(1)},
            ))
            i += 1
            continue

        # 引用
        if stripped.startswith(">"):
            quote_lines = []
            while i < len(lines) and lines[i].strip().startswith(">"):
                quote_lines.append(lines[i].strip().lstrip(">").strip())
                i += 1
            blocks.append(Block(kind="quote", content="\n".join(quote_lines)))
            continue

        # 无序列表
        if re.match(r"^[-*+]\s+", stripped):
            item_lines = []
            while i < len(lines) and re.match(r"^[-*+]\s+", lines[i].strip()):
                item_lines.append(re.sub(r"^[-*+]\s+", "", lines[i].strip()))
                i += 1
            for item in item_lines:
                blocks.append(Block(kind="bullet", content=item))
            continue

        # 有序列表
        if re.match(r"^\d+\.\s+", stripped):
            item_lines = []
            while i < len(lines) and re.match(r"^\d+\.\s+", lines[i].strip()):
                item_lines.append(re.sub(r"^\d+\.\s+", "", lines[i].strip()))
                i += 1
            for idx, item in enumerate(item_lines, 1):
                blocks.append(Block(kind="bullet", content=f"{idx}. {item}"))
            continue

        # 表格（简单识别：有 |）
        if "|" in line and i + 1 < len(lines) and re.match(r"^\s*\|?\s*:?-+:?\s*\|", lines[i + 1]):
            table_lines = [line]
            i += 1
            # 跳过分隔线
            i += 1
            while i < len(lines) and "|" in lines[i]:
                table_lines.append(lines[i])
                i += 1
            blocks.append(Block(kind="table", content="\n".join(table_lines)))
            continue

        # 普通段落（合并连续行）
        para_lines = [line]
        i += 1
        while i < len(lines) and lines[i].strip() and not (
            lines[i].strip().startswith(("#", ">", "-", "*", "+", "!"))
            or re.match(r"^\d+\.\s+", lines[i].strip())
            or "|" in lines[i]
        ):
            para_lines.append(lines[i])
            i += 1
        blocks.append(Block(kind="p", content=" ".join(l.strip() for l in para_lines)))

    return blocks


def md_inline_to_rl(text: str) -> str:
    """Markdown inline → ReportLab mini HTML."""
    # 粗体 **text**
    text = re.sub(r"\*\*([^*]+)\*\*", r"<b>\1</b>", text)
    # 斜体 *text*
    text = re.sub(r"(?<!\*)\*([^*]+)\*(?!\*)", r"<i>\1</i>", text)
    # 行内代码 `code`
    text = re.sub(r"`([^`]+)`", r'<font face="Courier">\1</font>', text)
    # 引用标签 [src_001] → 上标
    text = re.sub(r"\[(src_\d+)\]", r"<super><font size=8>[\1]</font></super>", text)
    # 链接 [text](url) 保留 text
    text = re.sub(r"\[([^\]]+)\]\(([^)]+)\)", r"\1", text)
    return text


# ============================================================
# 文档模板与渲染
# ============================================================

@dataclass
class Manifest:
    slug: str
    topic: str
    subtitle: str
    author: str
    date: str
    type: str
    version: str
    disclaimer: str

    @classmethod
    def load(cls, path: Path) -> "Manifest":
        data = json.loads(path.read_text(encoding="utf-8"))
        return cls(
            slug=data.get("slug", ""),
            topic=data.get("topic", "未命名研究"),
            subtitle=data.get("subtitle", ""),
            author=data.get("author", "Deep Research 系统"),
            date=data.get("date", ""),
            type=data.get("type", ""),
            version=data.get("version", "1.0"),
            disclaimer=data.get("disclaimer", ""),
        )


def make_page_decorator(manifest: Manifest, styles: StyleSheet1):
    """生成普通页的页眉页脚绘制函数。"""

    def draw(canvas, doc):
        canvas.saveState()
        # 页眉
        canvas.setFont("SrcSans-Light", 8)
        canvas.setFillColor(colors.HexColor("#9ca3af"))
        canvas.drawString(2 * cm, A4[1] - 1.2 * cm, manifest.topic[:30])
        canvas.drawRightString(A4[0] - 2 * cm, A4[1] - 1.2 * cm, manifest.type)
        canvas.setStrokeColor(colors.HexColor("#e5e7eb"))
        canvas.line(2 * cm, A4[1] - 1.4 * cm, A4[0] - 2 * cm, A4[1] - 1.4 * cm)
        # 页脚
        canvas.drawCentredString(A4[0] / 2, 1.2 * cm, f"— {doc.page} —")
        canvas.restoreState()

    return draw


def build_cover(manifest: Manifest, styles: StyleSheet1) -> List:
    """封面页 flowables。"""
    story = []
    story.append(Spacer(1, 4 * cm))
    story.append(Paragraph(manifest.topic, styles["cover-title"]))
    if manifest.subtitle:
        story.append(Paragraph(manifest.subtitle, styles["cover-subtitle"]))
    story.append(Spacer(1, 6 * cm))
    story.append(Paragraph(f"<b>类型</b>：{manifest.type}", styles["cover-meta"]))
    story.append(Paragraph(f"<b>作者</b>：{manifest.author}", styles["cover-meta"]))
    story.append(Paragraph(f"<b>日期</b>：{manifest.date}", styles["cover-meta"]))
    story.append(Paragraph(f"<b>版本</b>：v{manifest.version}", styles["cover-meta"]))
    story.append(PageBreak())
    return story


def build_disclaimer(manifest: Manifest, styles: StyleSheet1) -> List:
    """免责声明页。"""
    story = []
    story.append(Paragraph("免责声明", styles["h1"]))
    story.append(Spacer(1, 0.5 * cm))
    disclaimer = manifest.disclaimer or (
        "本报告基于公开信息与 AI 辅助研究生成，仅供参考，不构成投资、医疗或法律建议。"
        "数据截至报告生成日，使用者应自行核实关键数据并评估时效性。"
    )
    story.append(Paragraph(disclaimer, styles["body"]))
    story.append(PageBreak())
    return story


def build_body(blocks: List[Block], base_dir: Path, styles: StyleSheet1) -> List:
    """正文 flowables。"""
    story = []
    for block in blocks:
        if block.kind == "h1":
            # h1 前强制分页（每章新起一页）
            story.append(PageBreak())
            story.append(Paragraph(md_inline_to_rl(block.content), styles["h1"]))
        elif block.kind == "h2":
            story.append(Paragraph(md_inline_to_rl(block.content), styles["h2"]))
        elif block.kind == "h3":
            story.append(Paragraph(md_inline_to_rl(block.content), styles["h3"]))
        elif block.kind == "p":
            story.append(Paragraph(md_inline_to_rl(block.content), styles["body"]))
        elif block.kind == "quote":
            story.append(Paragraph(md_inline_to_rl(block.content), styles["quote"]))
        elif block.kind == "bullet":
            story.append(Paragraph("• " + md_inline_to_rl(block.content), styles["bullet"]))
        elif block.kind == "hr":
            story.append(PageBreak())
        elif block.kind == "image":
            img_path = base_dir / block.content
            if img_path.exists():
                try:
                    img = Image(str(img_path), width=15 * cm, height=10 * cm, kind="proportional")
                    story.append(img)
                    if block.meta and block.meta.get("caption"):
                        story.append(Paragraph(block.meta["caption"], styles["caption"]))
                except Exception as e:
                    story.append(Paragraph(
                        f"[图片加载失败：{block.content} — {e}]",
                        styles["caption"],
                    ))
            else:
                story.append(Paragraph(
                    f"[图片未找到：{block.content}]",
                    styles["caption"],
                ))
        elif block.kind == "table":
            try:
                table_flow = render_table(block.content, styles)
                story.append(table_flow)
            except Exception as e:
                story.append(Paragraph(f"[表格渲染失败: {e}]", styles["caption"]))
    return story


def render_table(md_table: str, styles: StyleSheet1) -> Table:
    """Markdown 表格 → ReportLab Table。自动计算均匀列宽，避免负宽度问题。"""
    rows = []
    body_style = ParagraphStyle(
        name="table-body",
        fontName="SrcSerif",
        fontSize=9,
        leading=14,
        wordWrap="CJK",
    )
    header_style = ParagraphStyle(
        name="table-header",
        fontName="SrcSans-Bold",
        fontSize=9,
        leading=14,
        wordWrap="CJK",
    )
    num_cols = 0
    for i, line in enumerate(md_table.strip().split("\n")):
        line = line.strip().strip("|")
        # 跳过分隔行（如 :---: | ---  等）
        if re.match(r"^[\s\-:|]+$", line):
            continue
        cells = [c.strip() for c in line.split("|")]
        if not any(cells):
            continue
        num_cols = max(num_cols, len(cells))
        # 第一行（表头）用 header_style
        style = header_style if not rows else body_style
        rows.append([Paragraph(md_inline_to_rl(c), style) for c in cells])

    if not rows:
        return Table([[Paragraph("", body_style)]])

    # 可用宽度：A4(595pt) - 左右各2cm边距 = 595 - 4*28.35 ≈ 481pt
    available_width = 17 * cm  # 约 481pt，保守取 17cm
    col_width = available_width / max(num_cols, 1)
    col_widths = [col_width] * num_cols

    # 统一列数（补齐短行）
    for row in rows:
        while len(row) < num_cols:
            row.append(Paragraph("", body_style))

    table = Table(rows, colWidths=col_widths, repeatRows=1)
    table.setStyle(TableStyle([
        ("BACKGROUND", (0, 0), (-1, 0), colors.HexColor("#e0e7ff")),
        ("FONTNAME", (0, 0), (-1, 0), "SrcSans-Bold"),
        ("FONTSIZE", (0, 0), (-1, -1), 9),
        ("GRID", (0, 0), (-1, -1), 0.5, colors.HexColor("#cbd5e1")),
        ("VALIGN", (0, 0), (-1, -1), "MIDDLE"),
        ("LEFTPADDING", (0, 0), (-1, -1), 4),
        ("RIGHTPADDING", (0, 0), (-1, -1), 4),
        ("TOPPADDING", (0, 0), (-1, -1), 3),
        ("BOTTOMPADDING", (0, 0), (-1, -1), 3),
    ]))
    return table


# ============================================================
# 主入口
# ============================================================

def main():
    parser = argparse.ArgumentParser(description="Deep Research ReportLab PDF 生成器")
    parser.add_argument("--input", required=True, help="输入 Markdown 路径")
    parser.add_argument("--manifest", required=True, help="manifest.json 路径")
    parser.add_argument("--output", required=True, help="输出 PDF 路径")
    parser.add_argument(
        "--fonts-dir",
        default=".opencode/templates/fonts",
        help="字体目录（默认 .opencode/templates/fonts）",
    )
    args = parser.parse_args()

    md_path = Path(args.input)
    manifest_path = Path(args.manifest)
    output_path = Path(args.output)
    fonts_dir = Path(args.fonts_dir)

    # 校验输入
    for p, label in [(md_path, "Markdown"), (manifest_path, "Manifest"), (fonts_dir, "字体目录")]:
        if not p.exists():
            print(f"❌ {label} 不存在：{p}", file=sys.stderr)
            sys.exit(1)

    # 注册字体
    register_fonts(fonts_dir)
    styles = build_styles()
    manifest = Manifest.load(manifest_path)

    # 解析 Markdown
    md_text = md_path.read_text(encoding="utf-8")
    blocks = parse_markdown(md_text)

    # 构建文档
    doc = BaseDocTemplate(
        str(output_path),
        pagesize=A4,
        leftMargin=2 * cm,
        rightMargin=2 * cm,
        topMargin=2 * cm,
        bottomMargin=2 * cm,
        title=manifest.topic,
        author=manifest.author,
    )

    # 两个 Frame：封面（无页眉页脚） / 正文
    cover_frame = Frame(
        2 * cm, 2 * cm,
        A4[0] - 4 * cm, A4[1] - 4 * cm,
        id="cover",
    )
    normal_frame = Frame(
        2 * cm, 2 * cm,
        A4[0] - 4 * cm, A4[1] - 4 * cm,
        id="normal",
    )
    decorator = make_page_decorator(manifest, styles)
    doc.addPageTemplates([
        PageTemplate(id="cover", frames=[cover_frame]),
        PageTemplate(id="normal", frames=[normal_frame], onPage=decorator),
    ])

    # 构建 story
    story: List = []
    story.extend(build_cover(manifest, styles))
    story.append(NextPageTemplate("normal"))
    story.extend(build_disclaimer(manifest, styles))
    story.extend(build_body(blocks, md_path.parent, styles))

    # 出稿
    doc.build(story)

    size = output_path.stat().st_size
    print(f"✅ PDF 生成成功：{output_path}")
    print(f"   文件大小：{size / 1024:.1f} KB")
    print(f"   字体数量：{len(FONT_MAP)}")
    print(f"   Block 数：{len(blocks)}")


if __name__ == "__main__":
    main()