"""候选抽取 prompt 构建（纯函数，无 IO）。

接收 ``(role, content)`` 元组列表（由 application 从 ORM 转换），产出
``(system, user)`` 消息对，喂给模型网关。模型返回的 JSON 由 ``extract`` 模块解析。
"""

from collections.abc import Sequence

PROFILE_FIELDS = (
    "display_name",
    "birthday",
    "height",
    "weight",
    "background",
    "speaking_style",
)
MEMORY_TYPES = (
    "user",
    "preference",
    "event",
    "relationship",
    "skill",
    "goal",
    "other",
)
PERSONALITY_FIELDS = (
    "identity_profile",
    "role_destiny",
    "personality_seed",
    "expression_style",
    "relationship_pattern",
    "traits",
    "values",
    "emotion_baseline",
)


def _format_items(items: Sequence[tuple[str, str]]) -> str:
    lines = [f"[{idx}] ({role}) {content}" for idx, (role, content) in enumerate(items)]
    return "\n".join(lines)


def build_profile_extraction_messages(
    items: Sequence[tuple[str, str]],
) -> tuple[str, str]:
    system = (
        "你是资料分析助手。从用户提供的资料中提取人物档案字段候选，只提取明确出现的信息。"
        f"field 取自：{', '.join(PROFILE_FIELDS)}。"
        '以 JSON 数组返回，每个元素：{"field": str, "value": str, "confidence": 0~1, '
        '"reason": str, "evidence": [条目序号]}。'
        "evidence 为资料条目序号（[0]/[1]…）列表。若资料无档案信息，返回 []。"
        "只返回 JSON 数组，不要解释或 markdown。"
    )
    return system, f"资料：\n{_format_items(items)}"


def build_memory_extraction_messages(
    items: Sequence[tuple[str, str]],
) -> tuple[str, str]:
    system = (
        "你是记忆分析助手。从用户提供的资料中提取值得长期记住的记忆候选。"
        f"type 取自：{', '.join(MEMORY_TYPES)}。"
        '以 JSON 数组返回：{"type": str, "title": str, "content": str, '
        '"importance": 0~1, "sensitivity": "low|medium|high", "reason": str, '
        '"evidence": [条目序号]}。'
        "只提取有长期价值的非琐碎信息。若无可提取返回 []。只返回 JSON 数组。"
    )
    return system, f"资料：\n{_format_items(items)}"


def build_personality_extraction_messages(
    items: Sequence[tuple[str, str]], personality_summary: str
) -> tuple[str, str]:
    system = (
        "你是人格分析助手。基于用户提供的资料和当前人格，提出人格完善建议。"
        f"field 取自：{', '.join(PERSONALITY_FIELDS)}。"
        '以 JSON 数组返回：{"field": str, "change": str, "reason": str, '
        '"evidence": [条目序号]}。'
        "change 为建议写入该字段的新内容。只在资料充分支撑时提议。若无需完善返回 []。"
        "只返回 JSON 数组。"
    )
    user = (
        f"当前人格摘要：\n{personality_summary or '（尚未形成）'}\n\n资料：\n{_format_items(items)}"
    )
    return system, user