# -*- coding: utf-8 -*-
from odoo import models, fields, api


class GameCurrency(models.Model):
    _name = 'game.currency'
    _description = '游戏货币等级'
    _order = 'level asc'

    level = fields.Integer(string='等级', required=True)
    name = fields.Char(string='名称', required=True)
    desc = fields.Text(string='描述')
    rate = fields.Integer(
        string='兑换比例',
        default=1,
        help='多少单位本货币可兑换 1 单位下一等级货币。例如 100 墟铢 = 1 灵币，则墟铢的 rate 为 100。'
    )

    @api.model
    def convert(self, amount, from_level, to_level):
        """按等级汇率将 amount 从 from_level 换算为 to_level 货币。

        汇率方向：低等级 → 高等级 为除以 rate，高等级 → 低等级 为乘以 rate。
        最高等级货币（元玺）的 rate 固定为 1，仅作占位。
        """
        if from_level == to_level:
            return amount
        currencies = self.search_read([], ['level', 'rate'], order='level asc')
        rate_map = {c['level']: c['rate'] or 1 for c in currencies}

        if from_level < to_level:
            # 低等级 → 高等级：逐级除以兑换比例
            result = amount
            for lv in range(from_level, to_level):
                result = result / rate_map.get(lv, 1)
            return result
        else:
            # 高等级 → 低等级：逐级乘以兑换比例
            result = amount
            for lv in range(to_level, from_level):
                result = result * rate_map.get(lv, 1)
            return result