package rules

import (
	"encoding/json"
	"sort"
	"strconv"
	"strings"

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

// 赛事库 settings 表里的键名；与 migrations/event/0011_seed.sql 保持一致。
const (
	settingIndividualToTeamWeight = "standings.individual_to_team_weight"
	settingTieBreak               = "standings.tie_break"
	settingMedalCountsTeamEvents  = "standings.medal_counts_team_events"
	settingShowIndividualBoard    = "standings.show_individual_board"
	settingShowIndividualMedals   = "standings.show_individual_medals"
	settingRecordBonusEnabled     = "record_bonus.enabled"
	settingRecordBonusMode        = "record_bonus.mode"
	settingRecordBonusLevels      = "record_bonus.levels"
	settingManualEnabled          = "manual_adjustment.enabled"
	settingManualReasonRequired   = "manual_adjustment.reason_required"
)

// settingsFromPack 把规则包里能落到 settings 表的部分拍平成键值对。
// 破纪录档位库里没有表，用 JSON 存在 record_bonus.levels 里，避免导入时丢配置。
func settingsFromPack(pack *RulePack) map[string]string {
	levels, err := json.Marshal(pack.RecordBonus.Levels)
	if err != nil {
		levels = []byte("[]")
	}
	return map[string]string{
		settingIndividualToTeamWeight: formatFloat(pack.Standings.IndividualToTeamWeight),
		settingTieBreak:               strings.Join(pack.Standings.TieBreak, ","),
		settingMedalCountsTeamEvents:  formatBool(pack.Standings.MedalCountsTeamEventsEnabled()),
		settingShowIndividualBoard:    formatBool(pack.Standings.ShowIndividualBoardEnabled()),
		settingShowIndividualMedals:   formatBool(pack.Standings.ShowIndividualMedalsEnabled()),
		settingRecordBonusEnabled:     formatBool(pack.RecordBonus.Enabled),
		settingRecordBonusMode:        string(pack.RecordBonus.Mode),
		settingRecordBonusLevels:      string(levels),
		settingManualEnabled:          formatBool(pack.ManualAdjustment.Enabled),
		settingManualReasonRequired:   formatBool(pack.ManualAdjustment.ReasonRequired),
	}
}

// settingsKeys 返回固定顺序的键名，保证差异预览与落库顺序稳定。
func settingsKeys() []string {
	keys := []string{
		settingIndividualToTeamWeight,
		settingTieBreak,
		settingMedalCountsTeamEvents,
		settingShowIndividualBoard,
		settingShowIndividualMedals,
		settingRecordBonusEnabled,
		settingRecordBonusMode,
		settingRecordBonusLevels,
		settingManualEnabled,
		settingManualReasonRequired,
	}
	sort.Strings(keys)
	return keys
}

func standingsFromSettings(m map[string]string) Standings {
	s := Standings{
		IndividualToTeamWeight: settingFloat(m, settingIndividualToTeamWeight, 1),
		TieBreak:               splitList(m[settingTieBreak]),
		MedalCountsTeamEvents:  BoolPtr(settingBool(m, settingMedalCountsTeamEvents, true)),
		ShowIndividualBoard:    BoolPtr(settingBool(m, settingShowIndividualBoard, true)),
		ShowIndividualMedals:   BoolPtr(settingBool(m, settingShowIndividualMedals, true)),
	}
	if len(s.TieBreak) == 0 {
		s.TieBreak = append([]string(nil), DefaultTieBreak...)
	}
	return s
}

func recordBonusFromSettings(m map[string]string) RecordBonus {
	rb := RecordBonus{
		Enabled: settingBool(m, settingRecordBonusEnabled, false),
		Mode:    modeOrDefault(m[settingRecordBonusMode]),
	}
	if raw := strings.TrimSpace(m[settingRecordBonusLevels]); raw != "" {
		var levels []RecordLevel
		if err := json.Unmarshal([]byte(raw), &levels); err == nil {
			rb.Levels = levels
		}
	}
	return rb
}

// RecordBonusFromSettings 从赛事库 settings 键值对还原破纪录加分配置（含档位）。
// 上层加载器必须经此函数读取 record_bonus.levels，否则档位缺失、破纪录加分恒为 0。
func RecordBonusFromSettings(m map[string]string) domain.RecordBonusConfig {
	return recordBonusFromSettings(m).ToDomain()
}

func manualAdjustmentFromSettings(m map[string]string) ManualAdjustment {
	return ManualAdjustment{
		Enabled:        settingBool(m, settingManualEnabled, false),
		ReasonRequired: settingBool(m, settingManualReasonRequired, true),
	}
}

func settingFloat(m map[string]string, key string, def float64) float64 {
	raw, ok := m[key]
	if !ok {
		return def
	}
	v, err := strconv.ParseFloat(strings.TrimSpace(raw), 64)
	if err != nil {
		return def
	}
	return v
}

func settingBool(m map[string]string, key string, def bool) bool {
	raw, ok := m[key]
	if !ok {
		return def
	}
	switch strings.ToLower(strings.TrimSpace(raw)) {
	case "true", "1", "yes", "on":
		return true
	case "false", "0", "no", "off":
		return false
	default:
		return def
	}
}

func formatFloat(v float64) string { return strconv.FormatFloat(v, 'g', -1, 64) }

func formatBool(v bool) string {
	if v {
		return "true"
	}
	return "false"
}

func splitList(raw string) []string {
	if strings.TrimSpace(raw) == "" {
		return nil
	}
	parts := strings.Split(raw, ",")
	out := make([]string, 0, len(parts))
	for _, p := range parts {
		if p = strings.TrimSpace(p); p != "" {
			out = append(out, p)
		}
	}
	return out
}

func modeOrDefault(raw string) domain.RecordBonusMode {
	if strings.TrimSpace(raw) == "" {
		return domain.RecordBonusMax
	}
	return domain.RecordBonusMode(strings.TrimSpace(raw))
}