import io
import os
import re
import base64
import logging
import tempfile
from datetime import datetime
from docx import Document
from docx.shared import Cm
import lib.db as db
from lib.image_processor import process_image
from lib import field_codes

logger = logging.getLogger(__name__)


def _new_trace_id():
    return datetime.now().strftime('%Y%m%d%H%M%S%f') + f'_{os.getpid()}'


def sign_word(docx_data, params, log_source='前端操作', trace_id=None, client_ip=None):
    if trace_id is None:
        trace_id = _new_trace_id()
    logger.info("[签章流程] ====== 开始处理 ====== trace_id=%s", trace_id,
                extra={'log_source': log_source, 'trace_id': trace_id})

    try:
        docx_name = params.get('docx_name', '')
        logger.info("[签章流程] 文件名: %s", docx_name,
                    extra={'log_source': log_source, 'trace_id': trace_id})

        if not docx_name.lower().endswith('.docx'):
            logger.error("[参数校验] 文件类型错误: %s, 仅支持.docx", docx_name,
                         extra={'log_source': log_source, 'trace_id': trace_id})
            return None, {'success': False, 'code': 'INVALID_FILE_TYPE',
                          'message': f'仅支持.docx格式，当前: {docx_name}',
                          'trace_id': trace_id}

        match_mode = params.get('match_mode', '')
        if match_mode not in ('upload', 'id', 'name', 'auto'):
            logger.error("[参数校验] 匹配模式无效: %s", match_mode,
                         extra={'log_source': log_source, 'trace_id': trace_id})
            return None, {'success': False, 'code': 'INVALID_MATCH_MODE',
                          'message': f'匹配模式无效: {match_mode}', 'trace_id': trace_id}

        logger.info("[签章流程] 匹配模式: %s", match_mode,
                    extra={'log_source': log_source, 'trace_id': trace_id})

        try:
            doc = Document(io.BytesIO(docx_data))
        except Exception as e:
            logger.error("[参数校验] Word文档解析失败: %s", str(e),
                         extra={'log_source': log_source, 'trace_id': trace_id})
            return None, {'success': False, 'code': 'INVALID_DOCX',
                          'message': f'Word文档解析失败或已损坏: {e}', 'trace_id': trace_id}
        logger.info("[签章流程] Word文档加载成功",
                    extra={'log_source': log_source, 'trace_id': trace_id})

        stamps = params.get('stamps', [])
        use_global_align = params.get('use_global_align', True)
        align_h = params.get('align_h', 'left')
        align_v = params.get('align_v', 'center')
        use_global_height = params.get('use_global_height', True)
        global_height = params.get('height')
        use_global_noise = params.get('use_global_noise', True)
        global_noise = params.get('noise_level', 0)
        use_global_rotate = params.get('use_global_rotate', True)
        global_rotate_min = params.get('rotate_min', 0)
        global_rotate_max = params.get('rotate_max', 0)
        relax_layout = params.get('relax_layout', True)

        if match_mode == 'auto':
            stamps = [s for s in stamps if (s.get('marker') or '').strip()]
            if not stamps:
                scanned = field_codes.scan_user_markers(doc, log_source=log_source)
                stamps = [{'marker': item['marker']} for item in scanned]
                logger.info("[签章流程] auto模式扫描到 %d 个标记", len(stamps),
                            extra={'log_source': log_source, 'trace_id': trace_id})

        if len(stamps) > 100:
            logger.error("[参数校验] 盖章项超过100个限制: %d", len(stamps),
                         extra={'log_source': log_source, 'trace_id': trace_id})
            return None, {'success': False, 'code': 'TOO_MANY_STAMPS',
                          'message': '盖章项超过100个限制', 'trace_id': trace_id}

        warnings = []
        success_count = 0

        for i, stamp in enumerate(stamps):
            logger.info("[签章流程] ---- 处理盖章项 %d/%d ----", i + 1, len(stamps),
                        extra={'log_source': log_source, 'trace_id': trace_id})
            try:
                marker = stamp.get('marker', '')
                image_data = None
                stamp_is_signature = False

                if match_mode == 'upload':
                    image_b64 = stamp.get('image_base64', '')
                    if image_b64:
                        image_data = base64.b64decode(image_b64)
                        logger.info("[图片匹配] 使用上传图片: %s", stamp.get('image_filename', ''),
                                    extra={'log_source': log_source, 'trace_id': trace_id})
                    else:
                        warnings.append(f"盖章项{i + 1}: 缺少图片数据")
                        logger.warning("[图片匹配] 盖章项%d缺少图片数据", i + 1,
                                       extra={'log_source': log_source, 'trace_id': trace_id})
                        continue

                elif match_mode == 'id':
                    image_id = stamp.get('image_id', '')
                    if not image_id:
                        # SRS 3.1.3：空字符串改用 image_name 匹配
                        image_name = stamp.get('image_name', '')
                        if image_name:
                            logger.info("[图片匹配] image_id 为空，改用姓名查询: %s", image_name,
                                        extra={'log_source': log_source, 'trace_id': trace_id})
                            records = db.get_image_by_user_name(image_name)
                            if records:
                                if len(records) > 1:
                                    warnings.append(f"盖章项{i + 1}: 姓名={image_name} 匹配到 {len(records)} 条记录，使用第一条")
                                    logger.warning("[图片匹配] 姓名匹配多条: %s -> %d 条，使用第一条",
                                                   image_name, len(records),
                                                   extra={'log_source': log_source, 'trace_id': trace_id})
                                image_data = records[0]['sign_image']
                                stamp_is_signature = bool(records[0]['is_signature'])
                            else:
                                warnings.append(f"盖章项{i + 1}: 未找到姓名={image_name} 的记录")
                                logger.warning("[图片匹配] 未找到姓名=%s", image_name,
                                               extra={'log_source': log_source, 'trace_id': trace_id})
                                continue
                        else:
                            warnings.append(f"盖章项{i + 1}: 缺少人员ID和姓名")
                            logger.warning("[图片匹配] 盖章项%d缺少人员ID和姓名", i + 1,
                                           extra={'log_source': log_source, 'trace_id': trace_id})
                            continue
                    else:
                        logger.info("[图片匹配] 按ID查询: %s", image_id,
                                    extra={'log_source': log_source, 'trace_id': trace_id})
                        record = db.get_image_by_user_id(image_id)
                        if record:
                            image_data = record['sign_image']
                            stamp_is_signature = bool(record['is_signature'])
                            logger.info("[图片匹配] ID匹配成功: %s", image_id,
                                        extra={'log_source': log_source, 'trace_id': trace_id})
                        else:
                            warnings.append(f"盖章项{i + 1}: 未找到ID={image_id} 的记录")
                            logger.warning("[图片匹配] 未找到ID=%s", image_id,
                                           extra={'log_source': log_source, 'trace_id': trace_id})
                            continue

                elif match_mode == 'name':
                    image_name = stamp.get('image_name', '')
                    if not image_name:
                        warnings.append(f"盖章项{i + 1}: 缺少人员姓名")
                        logger.warning("[图片匹配] 盖章项%d缺少人员姓名", i + 1,
                                       extra={'log_source': log_source, 'trace_id': trace_id})
                        continue
                    logger.info("[图片匹配] 按姓名查询: %s", image_name,
                                extra={'log_source': log_source, 'trace_id': trace_id})
                    records = db.get_image_by_user_name(image_name)
                    if records:
                        if len(records) > 1:
                            warnings.append(f"盖章项{i + 1}: 姓名={image_name} 匹配到 {len(records)} 条记录，使用第一条")
                            logger.warning("[图片匹配] 姓名匹配多条: %s -> %d 条，使用第一条",
                                           image_name, len(records),
                                           extra={'log_source': log_source, 'trace_id': trace_id})
                        image_data = records[0]['sign_image']
                        stamp_is_signature = bool(records[0]['is_signature'])
                        logger.info("[图片匹配] 姓名匹配成功: %s", image_name,
                                    extra={'log_source': log_source, 'trace_id': trace_id})
                    else:
                        warnings.append(f"盖章项{i + 1}: 未找到姓名={image_name} 的记录")
                        logger.warning("[图片匹配] 未找到姓名=%s", image_name,
                                       extra={'log_source': log_source, 'trace_id': trace_id})
                        continue

                elif match_mode == 'auto':
                    name_from_marker = marker
                    if name_from_marker.startswith('USER_'):
                        name_from_marker = name_from_marker[5:]
                    name_from_marker = field_codes._strip_switches(name_from_marker)
                    logger.info("[图片匹配] auto模式, 标记=%s, 查询姓名=%s", marker, name_from_marker,
                                extra={'log_source': log_source, 'trace_id': trace_id})
                    records = db.get_image_by_user_name(name_from_marker)
                    if records:
                        if len(records) > 1:
                            warnings.append(f"盖章项{i + 1}: 姓名={name_from_marker} 匹配多条，使用第一条")
                            logger.warning("[图片匹配] auto 姓名匹配多条: %s -> %d", name_from_marker, len(records),
                                           extra={'log_source': log_source, 'trace_id': trace_id})
                        image_data = records[0]['sign_image']
                        stamp_is_signature = bool(records[0]['is_signature'])
                        logger.info("[图片匹配] auto匹配成功: %s", name_from_marker,
                                    extra={'log_source': log_source, 'trace_id': trace_id})
                    else:
                        warnings.append(f"盖章项{i + 1}: auto模式未找到姓名={name_from_marker} 的记录")
                        logger.warning("[图片匹配] auto未找到姓名=%s", name_from_marker,
                                       extra={'log_source': log_source, 'trace_id': trace_id})
                        continue

                if not image_data:
                    warnings.append(f"盖章项{i + 1}: 无有效图片数据")
                    continue

                is_sig = stamp.get('is_signature', stamp_is_signature)
                h = _resolve_height(stamp, use_global_height, global_height)
                noise = _resolve_noise(stamp, use_global_noise, global_noise)
                rot_min, rot_max = _resolve_rotate(stamp, use_global_rotate, global_rotate_min, global_rotate_max)
                s_align_h = stamp.get('align_h') if not use_global_align else align_h
                s_align_v = stamp.get('align_v') if not use_global_align else align_v

                processed = process_image(
                    image_data,
                    is_signature=is_sig,
                    noise_level=noise,
                    rotate_min=rot_min,
                    rotate_max=rot_max,
                    log_source=log_source,
                )

                # ============= 调试：把"即将插入文档的图"落到磁盘 =============
                # 目的：直接对比项目实际产出的图 vs 测试脚本（image_test/process.py）的输出
                # 落盘位置: image_test/output/project_run/<trace_id>_<stamp_idx>_*.png
                try:
                    import os as _os
                    _debug_dir = _os.path.join(
                        _os.path.dirname(_os.path.dirname(_os.path.abspath(__file__))),
                        'image_test', 'output', 'project_run'
                    )
                    _os.makedirs(_debug_dir, exist_ok=True)
                    _tag = f"{trace_id or 'no_trace'}_stamp{i + 1}"
                    with open(_os.path.join(_debug_dir, f"{_tag}_1_input.png"), 'wb') as _f:
                        _f.write(image_data)
                    with open(_os.path.join(_debug_dir, f"{_tag}_2_processed.png"), 'wb') as _f:
                        _f.write(processed)
                    logger.info("[签章流程][DEBUG] 已保存处理前后对比图到 %s (tag=%s)",
                                _debug_dir, _tag,
                                extra={'log_source': log_source, 'trace_id': trace_id})
                except Exception as _e:
                    logger.warning("[签章流程][DEBUG] 保存调试图失败: %s", str(_e),
                                   extra={'log_source': log_source, 'trace_id': trace_id})
                # ============= 调试结束 =============

                inserted = _insert_signature_image(doc, marker, processed, s_align_h, s_align_v,
                                                    height_cm=h,
                                                    relax_layout=relax_layout,
                                                    log_source=log_source, trace_id=trace_id)
                if inserted > 0:
                    success_count += inserted
                    logger.info("[签章流程] 盖章项%d签章成功: marker=%s, 插入%d处",
                                i + 1, marker, inserted,
                                extra={'log_source': log_source, 'trace_id': trace_id})
                else:
                    warnings.append(f"盖章项{i + 1}: 未找到标记 '{marker}'")
                    logger.warning("[签章流程] 未找到标记: %s", marker,
                                   extra={'log_source': log_source, 'trace_id': trace_id})

            except Exception as e:
                warnings.append(f"盖章项{i + 1}: 处理异常 - {str(e)}")
                logger.error("[签章流程] 盖章项%d处理异常: %s", i + 1, str(e),
                             extra={'log_source': log_source, 'trace_id': trace_id})

        output_buf = io.BytesIO()
        doc.save(output_buf)
        output_buf.seek(0)
        result_data = output_buf.read()

        base_name = os.path.splitext(docx_name)[0]
        output_name = f"{base_name}_signed.docx"

        logger.info("[签章流程] ====== 处理完成 ====== 成功%d项, 告警%d条, trace_id=%s",
                    success_count, len(warnings), trace_id,
                    extra={'log_source': log_source, 'trace_id': trace_id})

        return {'data': result_data, 'filename': output_name,
                'warnings': warnings, 'trace_id': trace_id,
                'success_count': success_count}, None

    except Exception as e:
        logger.error("[签章流程] 处理失败: %s", str(e),
                     extra={'log_source': log_source, 'trace_id': trace_id})
        return None, {'success': False, 'code': 'INTERNAL_ERROR',
                      'message': str(e), 'trace_id': trace_id}


def _insert_signature_image(doc, marker, image_data, align_h, align_v, height_cm=None,
                            relax_layout=True,
                            log_source='前端操作', trace_id=None):
    """插入签名图片到 marker 对应的 SET 域后。

    ``height_cm`` 为用户配置的目标高度（厘米）。若为 None，则**透传 None 给
    insert_image_after_field**，由后者根据插入位置的段落行高 + 字号自动推算
    （`_auto_size_height_cm`）。

    ``relax_layout`` 透传给 :func:`field_codes.insert_image_after_field`，
    控制是否自动放宽段落 / 表格行的固定高度约束以避免签名被裁剪。
    """
    with tempfile.NamedTemporaryFile(suffix='.png', delete=False) as tmp:
        tmp.write(image_data)
        tmp_path = tmp.name

    try:
        width_cm = None
        if height_cm and height_cm > 0:
            from PIL import Image as PILImage
            img = PILImage.open(io.BytesIO(image_data))
            img_w, img_h = img.size
            width_cm = img_w / img_h * height_cm if img_h else height_cm

        count = field_codes.insert_image_after_field(
            doc, marker, tmp_path, width_cm, height_cm,
            log_source=log_source, relax_layout=relax_layout,
        )
        return count
    finally:
        try:
            os.unlink(tmp_path)
        except Exception:
            pass


def _resolve_height(stamp, use_global, global_val):
    if use_global:
        if global_val in (None, ""):
            return None
        try:
            h = float(global_val)
            if 0.1 <= h <= 10.0:
                return round(h, 1)
        except (ValueError, TypeError):
            return None
        return None
    h = stamp.get('height')
    if h not in (None, ""):
        try:
            h = float(h)
            if 0.1 <= h <= 10.0:
                return round(h, 1)
        except (ValueError, TypeError):
            pass
    return None


def _resolve_noise(stamp, use_global, global_val):
    if use_global:
        try:
            return int(global_val) if global_val not in (None, "") else 0
        except (ValueError, TypeError):
            return 0
    n = stamp.get('noise_level')
    if n not in (None, ""):
        try:
            n = int(n)
            if 0 <= n <= 10:
                return n
        except (ValueError, TypeError):
            pass
    return 0


def _resolve_rotate(stamp, use_global, global_min, global_max):
    if use_global:
        try:
            rmin = int(global_min) if global_min not in (None, "") else 0
        except (ValueError, TypeError):
            rmin = 0
        try:
            rmax = int(global_max) if global_max not in (None, "") else 0
        except (ValueError, TypeError):
            rmax = 0
        return max(-180, min(180, rmin)), max(-180, min(180, rmax))
    r_min = stamp.get('rotate_min', 0)
    r_max = stamp.get('rotate_max', 0)
    try:
        r_min = max(-180, min(180, int(r_min)))
    except (ValueError, TypeError):
        r_min = 0
    try:
        r_max = max(-180, min(180, int(r_max)))
    except (ValueError, TypeError):
        r_max = 0
    return r_min, r_max