"""SQLite 连接与幂等初始化（结题报告初稿助手）。

业务表 4 张：
- closing_projects（结题项目，含预期指标，可编辑）
- achievements（成果清单，可编辑）
- expense_items（决算明细，可编辑）
- report_drafts（初稿记录，只读，生成自动写入）

表间禁止 SQLite 外键，仅存业务 id（见 references/SCHEMA.md）。
"""

from __future__ import annotations

import sqlite3

from db.display_metadata import (
    init_display_metadata,
    seed_column_metadata_batch,
    upsert_table_metadata,
)
from db.timestamp_columns import init_updated_at_trigger
from util.runtime_paths import get_db_path


def get_conn() -> sqlite3.Connection:
    return sqlite3.connect(get_db_path())


_CLOSING_PROJECTS_DDL = """
CREATE TABLE IF NOT EXISTS closing_projects (
    id             INTEGER PRIMARY KEY AUTOINCREMENT,
    project_no     TEXT NOT NULL UNIQUE,
    project_name   TEXT,
    pi_name        TEXT,
    department     TEXT,
    program        TEXT,
    start_date     TEXT,
    end_date       TEXT,
    approved_budget REAL,
    expected_json  TEXT,
    annual_report_excerpt TEXT,
    status         TEXT NOT NULL DEFAULT '待结题',
    created_at     INTEGER NOT NULL DEFAULT (unixepoch()),
    updated_at     INTEGER NOT NULL DEFAULT (unixepoch())
)
"""

_ACHIEVEMENTS_DDL = """
CREATE TABLE IF NOT EXISTS achievements (
    id                INTEGER PRIMARY KEY AUTOINCREMENT,
    project_no        TEXT NOT NULL,
    achievement_type  TEXT NOT NULL,
    title             TEXT,
    venue_or_no       TEXT,
    ach_date          TEXT,
    is_representative INTEGER NOT NULL DEFAULT 0,
    note              TEXT,
    created_at        INTEGER NOT NULL DEFAULT (unixepoch()),
    updated_at        INTEGER NOT NULL DEFAULT (unixepoch())
)
"""

_EXPENSE_ITEMS_DDL = """
CREATE TABLE IF NOT EXISTS expense_items (
    id          INTEGER PRIMARY KEY AUTOINCREMENT,
    project_no  TEXT NOT NULL,
    category    TEXT NOT NULL,
    amount      REAL NOT NULL,
    occurred_date TEXT,
    description TEXT,
    created_at  INTEGER NOT NULL DEFAULT (unixepoch()),
    updated_at  INTEGER NOT NULL DEFAULT (unixepoch())
)
"""

_REPORT_DRAFTS_DDL = """
CREATE TABLE IF NOT EXISTS report_drafts (
    id                    INTEGER PRIMARY KEY AUTOINCREMENT,
    batch_no              TEXT NOT NULL,
    project_no            TEXT,
    project_name          TEXT,
    completion_json       TEXT,
    narrative_points_json TEXT,
    draft_file            TEXT,
    preview_file          TEXT,
    created_at            INTEGER NOT NULL DEFAULT (unixepoch())
)
"""

_REPORT_DRAFTS_INDEX = """
CREATE INDEX IF NOT EXISTS idx_report_drafts_batch
ON report_drafts(batch_no)
"""

_TS_COLUMN_NAMES = {"created_at", "updated_at"}


def _col(column_name: str, display_name: str, description: str, **extra: object) -> dict[str, object]:
    base: dict[str, object] = {
        "column_name": column_name,
        "display_name": display_name,
        "description": description,
        "visible": 1,
        "searchable": 0,
        "editable": 0,
    }
    base.update(extra)
    if column_name in _TS_COLUMN_NAMES:
        base["display_type"] = "datetime_unix_seconds"
    return base


_CLOSING_PROJECTS_COLUMNS: tuple[dict[str, object], ...] = (
    _col("id", "编号", "主键", searchable=1),
    _col("project_no", "项目编号", "项目唯一编号。", searchable=1),
    _col("project_name", "项目名称", "项目全称。", searchable=1, editable=1),
    _col("pi_name", "负责人", "项目负责人姓名。", searchable=1, editable=1),
    _col("department", "所属学院", "二级学院/单位。", searchable=1, editable=1),
    _col("program", "项目类型", "如 国家自然科学基金（青年/面上）。", searchable=1, editable=1),
    _col("start_date", "执行期开始", "YYYY-MM-DD。", searchable=1, editable=1),
    _col("end_date", "执行期结束", "YYYY-MM-DD。", searchable=1, editable=1),
    _col("approved_budget", "立项经费", "立项批准经费（元）；用于决算结余与预算符合性结论。", editable=1, display_type="number"),
    _col("expected_json", "预期成果指标", "如 [{\"type\":\"论文\",\"target\":3,\"unit\":\"篇\"}]。", visible=0, display_type="textarea", editable=1),
    _col("annual_report_excerpt", "年度报告摘句", "年度/中期报告关键句（分号分隔），供叙事素材。", visible=0, display_type="textarea", editable=1),
    _col("status", "状态", "待结题 / 初稿已生成 / 已提交。", searchable=1, editable=1, options_json='[{"value":"待结题","label":"待结题"},{"value":"初稿已生成","label":"初稿已生成"},{"value":"已提交","label":"已提交"}]'),
    _col("created_at", "创建时间", "记录创建时间（Unix 秒级，自动生成）。"),
    _col("updated_at", "更新时间", "记录最后更新时间（Unix 秒级，自动维护）。"),
)

_ACHIEVEMENTS_COLUMNS: tuple[dict[str, object], ...] = (
    _col("id", "编号", "主键", searchable=1),
    _col("project_no", "项目编号", "所属项目编号。", searchable=1),
    _col("achievement_type", "成果类型", "论文 / 专利 / 人才培养 / 其他。", searchable=1, editable=1, options_json='[{"value":"论文","label":"论文"},{"value":"专利","label":"专利"},{"value":"人才培养","label":"人才培养"},{"value":"其他","label":"其他"}]'),
    _col("title", "成果名称", "论文标题/专利名/成果描述。", searchable=1, editable=1),
    _col("venue_or_no", "期刊/专利号", "发表期刊或专利号。", editable=1),
    _col("ach_date", "日期", "发表/授权日期（YYYY-MM-DD）。", editable=1),
    _col("is_representative", "代表性成果", "1=代表本项目的标志性成果。", searchable=1, editable=1),
    _col("note", "备注", "说明。", editable=1),
    _col("created_at", "创建时间", "记录创建时间（Unix 秒级，自动生成）。"),
    _col("updated_at", "更新时间", "记录最后更新时间（Unix 秒级，自动维护）。"),
)

_EXPENSE_ITEMS_COLUMNS: tuple[dict[str, object], ...] = (
    _col("id", "编号", "主键", searchable=1),
    _col("project_no", "项目编号", "所属项目编号。", searchable=1),
    _col("category", "科目", "决算科目，如 差旅费、设备费。", searchable=1, editable=1),
    _col("amount", "金额", "支出金额（元）。", searchable=1, editable=1, display_type="number"),
    _col("occurred_date", "发生日期", "YYYY-MM-DD。", editable=1),
    _col("description", "原始摘要", "流水描述，供语义化转换参考。", visible=0, display_type="textarea", editable=1),
    _col("created_at", "创建时间", "记录创建时间（Unix 秒级，自动生成）。"),
    _col("updated_at", "更新时间", "记录最后更新时间（Unix 秒级，自动维护）。"),
)

_REPORT_DRAFTS_COLUMNS: tuple[dict[str, object], ...] = (
    _col("id", "记录编号", "主键，初稿记录编号。", searchable=1),
    _col("batch_no", "生成批次号", "同一次生成请求的批次号。", searchable=1),
    _col("project_no", "项目编号", "初稿对应项目。", searchable=1),
    _col("project_name", "项目名称", "初稿对应项目名。", searchable=1),
    _col("completion_json", "指标对比", "预期 vs 实际对比（JSON）。", visible=0, display_type="textarea"),
    _col("narrative_points_json", "叙事素材要点", "从成果与年度报告提取的要点（JSON）。", visible=0, display_type="textarea"),
    _col("draft_file", "Word 初稿", "生成的 docx 文件路径。", visible=0),
    _col("preview_file", "预览文件", "HTML 预览文件路径。", visible=0),
    _col("created_at", "创建时间", "记录创建时间（Unix 秒级，自动生成）。"),
)


def _ensure_columns(cursor, table_name: str, columns: tuple[tuple[str, str], ...]) -> None:
    """幂等迁移：老库缺列时 ALTER TABLE 补列（CREATE TABLE IF NOT EXISTS 不会改已有表）。"""
    cursor.execute(f"PRAGMA table_info({table_name})")
    existing = {str(row[1]) for row in cursor.fetchall()}
    for column_name, column_ddl in columns:
        if column_name not in existing:
            cursor.execute(f"ALTER TABLE {table_name} ADD COLUMN {column_ddl}")


def _init_closing_projects_metadata(cursor) -> None:
    cursor.execute(_CLOSING_PROJECTS_DDL)
    _ensure_columns(cursor, "closing_projects", (("approved_budget", "approved_budget REAL"),))
    init_updated_at_trigger(cursor, "closing_projects")
    upsert_table_metadata(
        cursor,
        table_name="closing_projects",
        display_name="结题项目",
        description="待结题项目与预期成果指标；初稿生成的数据源。",
        grid_help="预期指标为 JSON 数组（type/target/unit）；顶栏按钮可录入，行内可编辑。",
        visible=1,
        readonly=0,
        default_sort_json='[{"column":"id","direction":"desc"}]',
        default_visible_columns_json='["project_no","project_name","pi_name","program","end_date","status"]',
    )
    seed_column_metadata_batch(
        cursor,
        table_name="closing_projects",
        columns=_CLOSING_PROJECTS_COLUMNS,
        valid_column_names=[str(c["column_name"]) for c in _CLOSING_PROJECTS_COLUMNS],
    )


def _init_achievements_metadata(cursor) -> None:
    cursor.execute(_ACHIEVEMENTS_DDL)
    init_updated_at_trigger(cursor, "achievements")
    upsert_table_metadata(
        cursor,
        table_name="achievements",
        display_name="成果清单",
        description="实际取得的论文/专利/人才培养等成果；完成情况章节的数据源。",
        grid_help="按项目编号关联；代表性成果会优先进入初稿素材。",
        visible=1,
        readonly=0,
    )
    seed_column_metadata_batch(
        cursor,
        table_name="achievements",
        columns=_ACHIEVEMENTS_COLUMNS,
        valid_column_names=[str(c["column_name"]) for c in _ACHIEVEMENTS_COLUMNS],
    )


def _init_expense_items_metadata(cursor) -> None:
    cursor.execute(_EXPENSE_ITEMS_DDL)
    init_updated_at_trigger(cursor, "expense_items")
    upsert_table_metadata(
        cursor,
        table_name="expense_items",
        display_name="决算明细",
        description="经费流水明细；决算章节的数据源。",
        grid_help="金额单位元；按科目汇总后自动生成规范描述句。",
        visible=1,
        readonly=0,
    )
    seed_column_metadata_batch(
        cursor,
        table_name="expense_items",
        columns=_EXPENSE_ITEMS_COLUMNS,
        valid_column_names=[str(c["column_name"]) for c in _EXPENSE_ITEMS_COLUMNS],
    )


def _init_report_drafts_metadata(cursor) -> None:
    cursor.execute(_REPORT_DRAFTS_DDL)
    cursor.execute(_REPORT_DRAFTS_INDEX)
    upsert_table_metadata(
        cursor,
        table_name="report_drafts",
        display_name="初稿记录",
        description="每次生成的初稿记录：指标对比、素材要点与文件路径。",
        grid_help="Word 文件在 output 目录可下载；HTML 预览在侧栏查看。",
        visible=1,
        readonly=1,
        default_sort_json='[{"column":"id","direction":"desc"}]',
        default_visible_columns_json='["id","project_no","project_name","created_at"]',
    )
    seed_column_metadata_batch(
        cursor,
        table_name="report_drafts",
        columns=_REPORT_DRAFTS_COLUMNS,
        valid_column_names=[str(c["column_name"]) for c in _REPORT_DRAFTS_COLUMNS],
    )


def init_db() -> dict[str, int]:
    """幂等创建/迁移本地 SQLite 与数据管理元数据。"""
    conn = get_conn()
    try:
        cur = conn.cursor()
        init_display_metadata(cur)
        _init_closing_projects_metadata(cur)
        _init_achievements_metadata(cur)
        _init_expense_items_metadata(cur)
        _init_report_drafts_metadata(cur)
        conn.commit()
        return {}
    finally:
        conn.close()