//! 成长领域错误。
//!
//! 错误保持纯领域语义，例如章节参数非法、经验预算非法或用户/章节标识缺失。

use std::{error::Error, fmt};

#[derive(Clone, Debug, PartialEq, Eq)]
pub enum ProgressionFieldError {
    MissingUserId,
    MissingChapterId,
    InvalidChapterIndex,
    InvalidTotalChapters,
    InvalidLevel,
    InvalidEntryExitLevel,
    InvalidXpBudget,
    InvalidExpectedHostileDefeatCount,
}

impl fmt::Display for ProgressionFieldError {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match self {
            Self::MissingUserId => f.write_str("player_progression.user_id 不能为空"),
            Self::MissingChapterId => f.write_str("chapter_progression.chapter_id 不能为空"),
            Self::InvalidChapterIndex => {
                f.write_str("chapter_progression.chapter_index 必须大于 0")
            }
            Self::InvalidTotalChapters => f.write_str("chapter_progression.total_chapters 非法"),
            Self::InvalidLevel => f.write_str("player_progression.level 非法"),
            Self::InvalidEntryExitLevel => {
                f.write_str("chapter_progression.entry_level / exit_level 非法")
            }
            Self::InvalidXpBudget => f.write_str("chapter_progression 经验预算非法"),
            Self::InvalidExpectedHostileDefeatCount => {
                f.write_str("chapter_progression.expected_hostile_defeat_count 非法")
            }
        }
    }
}

impl Error for ProgressionFieldError {}