use chrono::TimeZone;
use serde::Deserialize;

/// CFC 统一响应包装 Result<T>（code=200 视为成功）
#[derive(Debug, Clone, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct ApiResult<T> {
    pub code: i32,
    pub message: Option<String>,
    pub data: Option<T>,
}

impl<T> ApiResult<T> {
    pub fn is_success(&self) -> bool {
        self.code == 200
    }
}

/// 兼容后端可能返回的日期格式：ISO 8601 字符串 或 epoch 毫秒数字。
///
/// Spring Boot 默认把 `java.util.Date` 序列化为 epoch 毫秒（数字）；项目内个别
/// 字段用 `@JsonFormat` 输出字符串。两种都接受，统一归一化为本地日期。
#[derive(Debug, Clone, Deserialize)]
#[serde(untagged)]
pub enum FlexDate {
    Iso(String),
    Millis(i64),
}

impl FlexDate {
    /// 归一化为本地时区日期（yyyy-MM-dd）。
    pub fn to_local_date(&self) -> Option<chrono::NaiveDate> {
        match self {
            FlexDate::Iso(s) => {
                if s.len() < 10 {
                    return None;
                }
                let head = &s[..10];
                chrono::NaiveDate::parse_from_str(head, "%Y-%m-%d").ok()
            }
            FlexDate::Millis(ms) => chrono::Local
                .timestamp_millis_opt(*ms)
                .single()
                .map(|dt| dt.date_naive()),
        }
    }
}

/// POST /api/tasks/today 返回的 Task（`tasks` 表）
#[derive(Debug, Clone, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct CfcTask {
    pub id: i64,
    pub title: Option<String>,
    pub status: Option<String>, // PENDING / IN_PROGRESS / COMPLETED / REJECTED
    pub deadline: Option<FlexDate>,
}

/// /api/energy/overview 五维维度项：{code,name,icon,element,energy,healthIndex}
#[derive(Debug, Clone, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct DimensionValue {
    pub code: Option<String>, // body/mind/wisdom/action/wealth
    pub name: Option<String>, // 身/心/智/行/富
    pub icon: Option<String>,
    pub element: Option<String>,
    #[serde(default)]
    pub energy: i32,
    #[serde(default)]
    pub health_index: i32,
}

#[derive(Debug, Clone, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct EnergyOverview {
    #[serde(default)]
    pub dimensions: Vec<DimensionValue>,
    #[serde(default)]
    pub total_energy: i32,
    #[serde(default)]
    pub total_health_index: i32,
}

/// /api/user/mascot/get → {"mascot": "xibao"|"fubao"|null}
#[derive(Debug, Clone, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct MascotInfo {
    pub mascot: Option<String>,
}

/// /api/health/water/list|create（`water_record` 表）
#[derive(Debug, Clone, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct WaterRecord {
    pub id: Option<i64>,
    pub member_id: Option<i64>,
    pub checkin_id: Option<i64>,
    pub amount_ml: Option<i32>,
    pub water_type: Option<String>,
    pub drunk_at: Option<FlexDate>,
    pub created_at: Option<FlexDate>,
}

/// /api/media/upload 返回的媒体记录（仅取所需字段，其余忽略）
#[derive(Debug, Clone, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct MediaRecord {
    #[allow(dead_code)]
    pub id: Option<i64>,
    pub url: Option<String>,
}

/// POST /api/auth/wechat-web/qr → {state, qrImage}
/// qrImage 为小程序码的 data:image/png;base64,... 数据 URI（测试模式为空串）
#[derive(Debug, Clone, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct WechatQrResp {
    pub state: String,
    #[serde(default)]
    pub qr_image: Option<String>,
}

/// POST /api/auth/wechat-web/poll → {status, token?, userId?, role?, nickname?, message?}
/// status: pending(等待扫码) / success / notfound(微信未绑定小程序账号) / expired / error
#[derive(Debug, Clone, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct WechatPollResp {
    pub status: String,
    pub token: Option<String>,
    pub user_id: Option<i64>,
    pub role: Option<String>,
    pub nickname: Option<String>,
    pub message: Option<String>,
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn parses_media_record_upload_response() {
        let json = r#"{"code":200,"message":"success","data":{"id":9,"type":"image","url":"https://cdn/x.png","creatorId":null}}"#;
        let r: ApiResult<MediaRecord> = serde_json::from_str(json).unwrap();
        assert!(r.is_success());
        let rec = r.data.unwrap();
        assert_eq!(rec.id, Some(9));
        assert_eq!(rec.url.as_deref(), Some("https://cdn/x.png"));
    }

    #[test]
    fn parses_task_with_iso_deadline() {
        let json = r#"{"id":3,"title":"喝水","status":"PENDING","deadline":"2026-08-15T10:00:00"}"#;
        let task: CfcTask = serde_json::from_str(json).unwrap();
        assert_eq!(task.id, 3);
        assert_eq!(task.status.as_deref(), Some("PENDING"));
        assert_eq!(
            task.deadline.as_ref().unwrap().to_local_date(),
            chrono::NaiveDate::from_ymd_opt(2026, 8, 15)
        );
    }

    #[test]
    fn parses_task_with_millis_deadline() {
        let json = r#"{"id":4,"title":"t","status":"PENDING","deadline":1786752000000}"#;
        let task: CfcTask = serde_json::from_str(json).unwrap();
        assert!(task.deadline.as_ref().unwrap().to_local_date().is_some());
    }

    #[test]
    fn parses_task_with_null_deadline() {
        let json = r#"{"id":5,"title":"t","status":"PENDING","deadline":null}"#;
        let task: CfcTask = serde_json::from_str(json).unwrap();
        assert!(task.deadline.is_none());
    }

    #[test]
    fn flex_date_millis_zero_is_a_valid_date() {
        let d: FlexDate = serde_json::from_str("0").unwrap();
        assert!(d.to_local_date().is_some());
    }

    #[test]
    fn parses_energy_overview_and_defaults_to_empty() {
        let json = r##"{"dimensions":[{"code":"body","name":"身","energy":65,"healthIndex":0}],"totalEnergy":65,"totalHealthIndex":0}"##;
        let e: EnergyOverview = serde_json::from_str(json).unwrap();
        assert_eq!(e.dimensions.len(), 1);
        assert_eq!(e.dimensions[0].energy, 65);
        assert_eq!(e.dimensions[0].code.as_deref(), Some("body"));

        let empty: EnergyOverview = serde_json::from_str(r#"{}"#).unwrap();
        assert!(empty.dimensions.is_empty());
        assert_eq!(empty.total_energy, 0);
    }

    #[test]
    fn parses_mascot_response() {
        let json = r#"{"code":200,"message":"success","data":{"mascot":"xibao"}}"#;
        let r: ApiResult<MascotInfo> = serde_json::from_str(json).unwrap();
        assert!(r.is_success());
        assert_eq!(r.data.unwrap().mascot.as_deref(), Some("xibao"));
    }

    #[test]
    fn parses_mascot_null() {
        let json = r#"{"code":200,"message":"success","data":{"mascot":null}}"#;
        let r: ApiResult<MascotInfo> = serde_json::from_str(json).unwrap();
        assert!(r.is_success());
        assert!(r.data.unwrap().mascot.is_none());
    }

    #[test]
    fn parses_wechat_qr_response() {
        let json = r#"{"code":200,"message":"success","data":{"state":"abc123","qrImage":"data:image/png;base64,AAAA"}}"#;
        let r: ApiResult<WechatQrResp> = serde_json::from_str(json).unwrap();
        assert!(r.is_success());
        let q = r.data.unwrap();
        assert_eq!(q.state, "abc123");
        assert!(q
            .qr_image
            .as_deref()
            .unwrap_or("")
            .starts_with("data:image/png;base64,"));
    }

    #[test]
    fn parses_wechat_qr_response_empty_image() {
        // 测试模式后端返回 qrImage=""：字段存在但为空
        let json = r#"{"code":200,"data":{"state":"abc123","qrImage":""}}"#;
        let r: ApiResult<WechatQrResp> = serde_json::from_str(json).unwrap();
        let q = r.data.unwrap();
        assert_eq!(q.state, "abc123");
        assert_eq!(q.qr_image.as_deref(), Some(""));
    }

    #[test]
    fn parses_wechat_poll_success_and_pending() {
        let ok: ApiResult<WechatPollResp> = serde_json::from_str(
            r#"{"code":200,"data":{"status":"success","token":"jwt","userId":7,"role":"parent","nickname":"牛"}}"#,
        )
        .unwrap();
        let p = ok.data.unwrap();
        assert_eq!(p.status, "success");
        assert_eq!(p.token.as_deref(), Some("jwt"));
        assert_eq!(p.user_id, Some(7));

        let pending: ApiResult<WechatPollResp> =
            serde_json::from_str(r#"{"code":200,"data":{"status":"pending"}}"#).unwrap();
        let p2 = pending.data.unwrap();
        assert_eq!(p2.status, "pending");
        assert!(p2.token.is_none());
    }
}