package export

import (
	"database/sql"
	"io"

	"github.com/xuri/excelize/v2"

	"git.yeij.top/AskaEth/Scoreboard/server/internal/domain"
)

// StandingsWorkbook 是「总表」的内容：总积分榜 + 单位奖牌榜 + 个人积分奖牌榜。
// 三个榜由 domain 的排名函数算出，本包只负责排版。
type StandingsWorkbook struct {
	Meta    Meta
	Team    []domain.StandingsRow
	Medal   []domain.MedalRow
	Athlete []domain.AthleteStandingsRow
}

var (
	teamColumns = []column{
		{"名次", 6, kindInt},
		{"单位代码", 10, kindCenter},
		{"单位名称", 26, kindText},
		{"总分", 9, kindNumber},
		{"团体项目分", 12, kindNumber},
		{"个人项目分", 12, kindNumber},
		{"金牌", 7, kindInt},
		{"银牌", 7, kindInt},
		{"铜牌", 7, kindInt},
		{"奖牌合计", 10, kindInt},
	}
	medalColumns = []column{
		{"名次", 6, kindInt},
		{"单位代码", 10, kindCenter},
		{"单位名称", 26, kindText},
		{"金牌", 7, kindInt},
		{"银牌", 7, kindInt},
		{"铜牌", 7, kindInt},
		{"奖牌合计", 10, kindInt},
		{"总分", 9, kindNumber},
	}
	athleteColumns = []column{
		{"名次", 6, kindInt},
		{"运动员", 16, kindText},
		{"单位代码", 10, kindCenter},
		{"单位名称", 24, kindText},
		{"总分", 9, kindNumber},
		{"金牌", 7, kindInt},
		{"银牌", 7, kindInt},
		{"铜牌", 7, kindInt},
		{"奖牌合计", 10, kindInt},
	}
)

// ExportStandingsXLSX 从赛事库读取并导出总表（三个 sheet），落盘到 dst。
// 仅测试使用（生产走 Load* + Write* 直接写响应体，不落盘）——见 saveWorkbook 的说明。
func ExportStandingsXLSX(db *sql.DB, dst string, opts Options) error {
	wb, err := LoadStandingsWorkbook(db, opts)
	if err != nil {
		return err
	}
	f, err := standingsFile(wb)
	if err != nil {
		return err
	}
	return saveWorkbook(f, dst)
}

// WriteStandingsXLSX 把已算好的总表写成 xlsx 流，供 HTTP 直接响应下载。
func WriteStandingsXLSX(w io.Writer, wb StandingsWorkbook) error {
	f, err := standingsFile(wb)
	if err != nil {
		return err
	}
	return f.Write(w)
}

func standingsFile(wb StandingsWorkbook) (*excelize.File, error) {
	return buildWorkbook("总积分榜", func(f *excelize.File, st *styleSet) error {
		return writeStandingsSheets(f, st, wb)
	})
}

func writeStandingsSheets(f *excelize.File, st *styleSet, wb StandingsWorkbook) error {
	meta := wb.Meta.normalized()
	specs := []struct {
		sheet string
		title string
		cols  []column
		rows  [][]any
	}{
		{"总积分榜", sheetTitle(meta, "总积分榜"), teamColumns, teamRows(wb.Team)},
		{"单位奖牌榜", sheetTitle(meta, "单位奖牌榜"), medalColumns, medalRows(wb.Medal)},
		{"个人积分奖牌榜", sheetTitle(meta, "个人积分奖牌榜"), athleteColumns, athleteRows(wb.Athlete)},
	}
	for _, s := range specs {
		if err := addSheet(f, s.sheet); err != nil {
			return err
		}
		if err := writeSheet(f, st, s.sheet, meta, s.title, s.cols, s.rows); err != nil {
			return err
		}
	}
	return nil
}

func teamRows(rows []domain.StandingsRow) [][]any {
	out := make([][]any, 0, len(rows))
	for _, r := range rows {
		out = append(out, []any{
			r.Rank, r.Code, displayName(r.Name, r.ShortName), r.Points,
			r.TeamOnlyPoints, r.IndividualPoints,
			r.Gold, r.Silver, r.Bronze, r.Medals,
		})
	}
	return out
}

func medalRows(rows []domain.MedalRow) [][]any {
	out := make([][]any, 0, len(rows))
	for _, r := range rows {
		out = append(out, []any{
			r.Rank, r.Code, displayName(r.Name, r.ShortName),
			r.Gold, r.Silver, r.Bronze, r.Total, r.Points,
		})
	}
	return out
}

func athleteRows(rows []domain.AthleteStandingsRow) [][]any {
	out := make([][]any, 0, len(rows))
	for _, r := range rows {
		out = append(out, []any{
			r.Rank, r.Name, r.TeamCode, displayName(r.TeamName, ""),
			r.Points, r.Gold, r.Silver, r.Bronze, r.Medals,
		})
	}
	return out
}

// displayName 优先用全称，其次简称；都为空时留空，不显示 "0" 之类的噪声。
func displayName(name, short string) string {
	if name != "" {
		return name
	}
	return short
}

// AllWorkbook 是「全部」导出：总表 + 全部分项成绩。
type AllWorkbook struct {
	Standings StandingsWorkbook
	Events    EventsWorkbook
}

// ExportAllXLSX 导出总表 + 全部分项成绩到一个多 sheet 工作簿。
// 仅测试使用（生产走 Load* + Write* 直接写响应体，不落盘）——见 saveWorkbook 的说明。
func ExportAllXLSX(db *sql.DB, dst string, opts Options) error {
	wb, err := LoadAllWorkbook(db, opts)
	if err != nil {
		return err
	}
	f, err := allFile(wb)
	if err != nil {
		return err
	}
	return saveWorkbook(f, dst)
}

// WriteAllXLSX 把「全部」写成 xlsx 流。
func WriteAllXLSX(w io.Writer, wb AllWorkbook) error {
	f, err := allFile(wb)
	if err != nil {
		return err
	}
	return f.Write(w)
}

// LoadAllWorkbook 一次性读取总表与全部分项成绩。
func LoadAllWorkbook(db *sql.DB, opts Options) (AllWorkbook, error) {
	standings, err := LoadStandingsWorkbook(db, opts)
	if err != nil {
		return AllWorkbook{}, err
	}
	events, err := LoadEventWorkbook(db, 0, opts)
	if err != nil {
		return AllWorkbook{}, err
	}
	return AllWorkbook{Standings: standings, Events: events}, nil
}

func allFile(wb AllWorkbook) (*excelize.File, error) {
	return buildWorkbook("总积分榜", func(f *excelize.File, st *styleSet) error {
		if err := writeStandingsSheets(f, st, wb.Standings); err != nil {
			return err
		}
		namer := &sheetNamer{}
		// 三个榜先登记名称，分项表才不会撞名。
		for _, n := range []string{"总积分榜", "单位奖牌榜", "个人积分奖牌榜"} {
			namer.add(n)
		}
		return writeEventSheets(f, st, wb.Events.Meta, wb.Events.Sheets, namer)
	})
}