import os
import re

from flask import Flask, redirect, render_template, request, url_for
from flask_sqlalchemy import SQLAlchemy


BASE_DIR = os.path.dirname(os.path.abspath(__file__))
DB_DIR = os.path.join(BASE_DIR, "data")
os.makedirs(DB_DIR, exist_ok=True)
DB_PATH = os.path.join(DB_DIR, "inventory.db")

app = Flask(__name__)
app.config["SQLALCHEMY_DATABASE_URI"] = f"sqlite:///{DB_PATH}"
app.config["SQLALCHEMY_TRACK_MODIFICATIONS"] = False
db = SQLAlchemy(app)


BOX_TYPES = {
	"small_28": {
		"label": "28格小盒大盒",
		"default_capacity": 28,
		"default_desc": "4连排小盒，常见摆放为竖向7排",
	},
	"medium_14": {
		"label": "14格中盒大盒",
		"default_capacity": 14,
		"default_desc": "装十四个中等盒子（尺寸不固定）",
	},
	"bag": {
		"label": "袋装清单",
		"default_capacity": 1,
		"default_desc": "用于较小防静电袋存放",
	},
}


class Box(db.Model):
	__tablename__ = "boxes"

	id = db.Column(db.Integer, primary_key=True)
	name = db.Column(db.String(100), nullable=False, unique=True)
	description = db.Column(db.String(255), nullable=True)
	box_type = db.Column(db.String(30), nullable=False, default="small_28")
	slot_capacity = db.Column(db.Integer, nullable=False, default=28)


class Component(db.Model):
	__tablename__ = "components"

	id = db.Column(db.Integer, primary_key=True)
	box_id = db.Column(db.Integer, db.ForeignKey("boxes.id"), nullable=False)
	slot_index = db.Column(db.Integer, nullable=False)

	part_no = db.Column(db.String(100), nullable=False)
	name = db.Column(db.String(120), nullable=False)
	specification = db.Column(db.String(120), nullable=True)
	quantity = db.Column(db.Integer, nullable=False, default=0)
	location = db.Column(db.String(120), nullable=True)
	note = db.Column(db.Text, nullable=True)

	box = db.relationship("Box", backref=db.backref("components", lazy=True))

	__table_args__ = (
		db.UniqueConstraint("box_id", "slot_index", name="uq_box_slot"),
	)


def ensure_default_box() -> None:
	defaults = [
		("默认28格大盒", "small_28"),
		("默认14格中盒", "medium_14"),
		("默认袋装清单", "bag"),
	]
	for box_name, box_type in defaults:
		exists = Box.query.filter_by(name=box_name).first()
		if exists:
			continue
		meta = BOX_TYPES[box_type]
		db.session.add(
			Box(
				name=box_name,
				description=meta["default_desc"],
				box_type=box_type,
				slot_capacity=meta["default_capacity"],
			)
		)
	db.session.commit()


def slot_data_for_box(box: Box):
	components = Component.query.filter_by(box_id=box.id).all()
	slot_map = {c.slot_index: c for c in components}
	slots = []
	for slot in range(1, box.slot_capacity + 1):
		slots.append({"slot": slot, "component": slot_map.get(slot)})
	return slots


def bag_items_for_box(box: Box):
	return (
		Component.query.filter_by(box_id=box.id)
		.order_by(Component.slot_index.asc())
		.all()
	)


def _parse_non_negative_int(raw_value: str, default_value: int = 0) -> int:
	raw = (raw_value or "").strip()
	if raw == "":
		return default_value
	value = int(raw)
	if value < 0:
		raise ValueError
	return value


def _add_bag_item(
	box: Box,
	part_no: str,
	name: str,
	quantity: int,
	specification: str,
	location: str,
	note: str,
) -> None:
	next_slot = (
		db.session.query(db.func.max(Component.slot_index))
		.filter(Component.box_id == box.id)
		.scalar()
		or 0
	) + 1

	item = Component(
		box_id=box.id,
		slot_index=next_slot,
		part_no=part_no,
		name=name,
		quantity=quantity,
		specification=specification or None,
		location=location or None,
		note=note or None,
	)
	db.session.add(item)

	if next_slot > box.slot_capacity:
		box.slot_capacity = next_slot


def render_box_page(box: Box, error: str = "", notice: str = ""):
	slots = slot_data_for_box(box)
	bag_items = bag_items_for_box(box) if box.box_type == "bag" else []
	return render_template(
		"box.html",
		box=box,
		slots=slots,
		bag_items=bag_items,
		box_types=BOX_TYPES,
		error=error,
		notice=notice,
	)


def ensure_box_schema() -> None:
	columns = {
		row[1]
		for row in db.session.execute(db.text("PRAGMA table_info(boxes)")).fetchall()
	}
	if "box_type" not in columns:
		db.session.execute(
			db.text(
				"ALTER TABLE boxes ADD COLUMN box_type VARCHAR(30) NOT NULL DEFAULT 'small_28'"
			)
		)
	if "slot_capacity" not in columns:
		db.session.execute(
			db.text(
				"ALTER TABLE boxes ADD COLUMN slot_capacity INTEGER NOT NULL DEFAULT 28"
			)
		)
	db.session.commit()


@app.route("/")
def index():
	boxes = Box.query.order_by(Box.id.asc()).all()
	groups = {key: [] for key in BOX_TYPES.keys()}
	for box in boxes:
		used_count = Component.query.filter_by(box_id=box.id).count()
		box_type = box.box_type if box.box_type in BOX_TYPES else "small_28"
		groups[box_type].append({"box": box, "used_count": used_count})
	return render_template("index.html", groups=groups, box_types=BOX_TYPES)


@app.route("/boxes/create", methods=["POST"])
def create_box():
	box_type = request.form.get("box_type", "small_28").strip()
	name = request.form.get("name", "").strip()
	description = request.form.get("description", "").strip()

	if box_type not in BOX_TYPES:
		return "无效盒子类型", 400
	if not name:
		return "盒子名称不能为空", 400

	if Box.query.filter_by(name=name).first():
		return "盒子名称已存在，请更换", 400

	meta = BOX_TYPES[box_type]
	box = Box(
		name=name,
		description=description or meta["default_desc"],
		box_type=box_type,
		slot_capacity=meta["default_capacity"],
	)
	db.session.add(box)
	db.session.commit()
	return redirect(url_for("index"))


@app.route("/box/<int:box_id>")
def view_box(box_id: int):
	box = Box.query.get_or_404(box_id)
	return render_box_page(box)


@app.route("/box/<int:box_id>/bags/add", methods=["POST"])
def add_bag_item(box_id: int):
	box = Box.query.get_or_404(box_id)
	if box.box_type != "bag":
		return "当前盒子不是袋装清单", 400

	part_no = request.form.get("part_no", "").strip()
	name = request.form.get("name", "").strip()
	specification = request.form.get("specification", "").strip()
	location = request.form.get("location", "").strip()
	note = request.form.get("note", "").strip()

	if not part_no or not name:
		return render_box_page(box, error="袋装新增失败: 料号和名称不能为空")

	try:
		quantity = _parse_non_negative_int(request.form.get("quantity", "0"), 0)
	except ValueError:
		return render_box_page(box, error="袋装新增失败: 数量必须是大于等于 0 的整数")

	_add_bag_item(box, part_no, name, quantity, specification, location, note)
	db.session.commit()
	return render_box_page(box, notice="已新增 1 条袋装记录")


@app.route("/box/<int:box_id>/bags/batch", methods=["POST"])
def add_bag_items_batch(box_id: int):
	box = Box.query.get_or_404(box_id)
	if box.box_type != "bag":
		return "当前盒子不是袋装清单", 400

	raw_lines = request.form.get("lines", "")
	lines = [line.strip() for line in raw_lines.splitlines() if line.strip()]
	if not lines:
		return render_box_page(box, error="批量新增失败: 请至少输入一行")

	invalid_lines = []
	added_count = 0
	for line_no, line in enumerate(lines, start=1):
		parts = [p.strip() for p in re.split(r"[,\t]", line)]
		while len(parts) < 6:
			parts.append("")

		part_no = parts[0]
		name = parts[1]
		quantity_raw = parts[2]
		specification = parts[3]
		location = parts[4]
		note = parts[5]

		if not part_no or not name:
			invalid_lines.append(f"第 {line_no} 行")
			continue

		try:
			quantity = _parse_non_negative_int(quantity_raw, 0)
		except ValueError:
			invalid_lines.append(f"第 {line_no} 行")
			continue

		_add_bag_item(box, part_no, name, quantity, specification, location, note)
		added_count += 1

	if added_count:
		db.session.commit()

	if invalid_lines and added_count == 0:
		return render_box_page(
			box,
			error="批量新增失败: 数据格式不正确（请检查: " + ", ".join(invalid_lines) + "）",
		)

	if invalid_lines:
		return render_box_page(
			box,
			notice=f"已新增 {added_count} 条，以下行被跳过: " + ", ".join(invalid_lines),
		)

	return render_box_page(box, notice=f"批量新增成功，共 {added_count} 条")


@app.route("/edit/<int:box_id>/<int:slot>", methods=["GET", "POST"])
def edit_component(box_id: int, slot: int):
	box = Box.query.get_or_404(box_id)
	if slot < 1 or slot > box.slot_capacity:
		return "无效的格子编号", 400

	component = Component.query.filter_by(box_id=box.id, slot_index=slot).first()

	if request.method == "POST":
		action = request.form.get("action", "save")

		if action == "delete":
			if component:
				db.session.delete(component)
				db.session.commit()
			return redirect(url_for("view_box", box_id=box.id))

		part_no = request.form.get("part_no", "").strip()
		name = request.form.get("name", "").strip()
		specification = request.form.get("specification", "").strip()
		quantity_raw = request.form.get("quantity", "0").strip()
		location = request.form.get("location", "").strip()
		note = request.form.get("note", "").strip()

		if not part_no or not name:
			error = "料号和名称不能为空"
			return render_template(
				"edit.html",
				box=box,
				slot=slot,
				component=component,
				error=error,
			)

		try:
			quantity = int(quantity_raw)
			if quantity < 0:
				raise ValueError
		except ValueError:
			error = "数量必须是大于等于 0 的整数"
			return render_template(
				"edit.html",
				box=box,
				slot=slot,
				component=component,
				error=error,
			)

		if component is None:
			component = Component(box_id=box.id, slot_index=slot)
			db.session.add(component)

		component.part_no = part_no
		component.name = name
		component.specification = specification or None
		component.quantity = quantity
		component.location = location or None
		component.note = note or None

		db.session.commit()
		return redirect(url_for("view_box", box_id=box.id))

	return render_template("edit.html", box=box, slot=slot, component=component)


@app.route("/scan")
def scan_page():
	keyword = request.args.get("q", "").strip()
	results = []
	if keyword:
		results = (
			Component.query.filter(
				db.or_(
					Component.part_no.ilike(f"%{keyword}%"),
					Component.name.ilike(f"%{keyword}%"),
				)
			)
			.order_by(Component.part_no.asc())
			.all()
		)
	return render_template("scan.html", keyword=keyword, results=results)


@app.route("/api/scan")
def scan_api():
	code = request.args.get("code", "").strip()
	if not code:
		return {"ok": False, "message": "code 不能为空"}, 400

	item = Component.query.filter_by(part_no=code).first()
	if not item:
		return {"ok": False, "message": "未找到元件"}, 404

	return {
		"ok": True,
		"data": {
			"id": item.id,
			"part_no": item.part_no,
			"name": item.name,
			"quantity": item.quantity,
			"box_id": item.box_id,
			"slot_index": item.slot_index,
		},
	}


def bootstrap() -> None:
	with app.app_context():
		db.create_all()
		ensure_box_schema()
		db.session.execute(
			db.text(
				"UPDATE boxes SET box_type = 'small_28' WHERE box_type IS NULL OR box_type = ''"
			)
		)
		db.session.execute(
			db.text("UPDATE boxes SET slot_capacity = 28 WHERE slot_capacity IS NULL")
		)
		db.session.commit()
		ensure_default_box()


bootstrap()


if __name__ == "__main__":
	app.run(host="0.0.0.0", port=5000, debug=True)