package bot

import (
	"context"
	"fmt"
	"strings"
	"time"

	"github.com/bwmarrin/discordgo"
)

func (b *Bot) handleMyStats(ctx context.Context, s *discordgo.Session, i *discordgo.InteractionCreate) {
	userID := i.Member.User.ID
	username := displayName(i.Member, i.Member.User)
	unit, _ := b.db.GetUserPreference(ctx, userID, i.GuildID)

	since := b.challengeStart(ctx, i.GuildID)
	challenge, _ := b.db.GetUserStats(ctx, i.GuildID, userID, since)
	yearly, _ := b.db.GetUserYearlyStats(ctx, i.GuildID, userID, time.Now().Year())
	allTime, _ := b.db.GetUserStats(ctx, i.GuildID, userID, time.Time{})
	pb, _ := b.db.GetUserPB(ctx, i.GuildID, userID)
	streak, _ := b.db.GetUserStreak(ctx, userID)
	kudos, _ := b.db.GetKudosReceived(ctx, i.GuildID, userID)

	if allTime.LogCount == 0 {
		respondEphemeral(s, i, "You haven't logged any distances yet. Post your rides in the fitness challenge channel!")
		return
	}

	name, _, _ := b.db.GetSetting(ctx, i.GuildID, "challenge_name")
	if name == "" {
		name = "Challenge"
	}

	var sb strings.Builder
	sb.WriteString(fmt.Sprintf("## 🚴 %s's Stats\n\n", username))
	sb.WriteString(fmt.Sprintf("**%s:** %s (%d ride%s)\n", name,
		formatDist(challenge.TotalKM, unit), challenge.LogCount, plural(challenge.LogCount)))
	sb.WriteString(fmt.Sprintf("**%d:** %s (%d ride%s)\n", time.Now().Year(),
		formatDist(yearly.TotalKM, unit), yearly.LogCount, plural(yearly.LogCount)))
	sb.WriteString(fmt.Sprintf("**All time:** %s (%d ride%s)\n\n",
		formatDist(allTime.TotalKM, unit), allTime.LogCount, plural(allTime.LogCount)))
	sb.WriteString(fmt.Sprintf("**Personal best:** %s\n", formatDist(pb, unit)))
	sb.WriteString(fmt.Sprintf("**Average ride:** %s\n", formatDist(allTime.TotalKM/float64(allTime.LogCount), unit)))
	if streak > 0 {
		sb.WriteString(fmt.Sprintf("**Current streak:** %d day%s 🔥\n", streak, plural(streak)))
	}
	if kudos > 0 {
		sb.WriteString(fmt.Sprintf("**Kudos received:** %d 👏\n", kudos))
	}

	respondEphemeral(s, i, sb.String())
}

func (b *Bot) handleHistory(ctx context.Context, s *discordgo.Session, i *discordgo.InteractionCreate) {
	userID := i.Member.User.ID
	unit, _ := b.db.GetUserPreference(ctx, userID, i.GuildID)
	count := int(optInt(i.ApplicationCommandData().Options, "count", 5))
	if count > 20 {
		count = 20
	}

	logs, err := b.db.GetUserHistory(ctx, i.GuildID, userID, count)
	if err != nil || len(logs) == 0 {
		respondEphemeral(s, i, "No rides logged yet.")
		return
	}

	var sb strings.Builder
	sb.WriteString(fmt.Sprintf("## 🚴 Your Last %d Ride%s\n\n", len(logs), plural(len(logs))))
	for _, l := range logs {
		sb.WriteString(fmt.Sprintf("**%s** — %s\n", l.LoggedAt.Format("02 Jan 2006"), formatDist(l.KM, unit)))
	}
	respondEphemeral(s, i, sb.String())
}

func (b *Bot) handlePB(ctx context.Context, s *discordgo.Session, i *discordgo.InteractionCreate) {
	userID := i.Member.User.ID
	unit, _ := b.db.GetUserPreference(ctx, userID, i.GuildID)
	pb, err := b.db.GetUserPB(ctx, i.GuildID, userID)
	if err != nil || pb == 0 {
		respondEphemeral(s, i, "No rides logged yet.")
		return
	}
	respondEphemeral(s, i, fmt.Sprintf("🏆 Your personal best single ride is **%s**!", formatDist(pb, unit)))
}

func (b *Bot) handleStreak(ctx context.Context, s *discordgo.Session, i *discordgo.InteractionCreate) {
	target := optUser(i.ApplicationCommandData().Options, "user", s)
	var userID, username string
	if target != nil {
		userID = target.ID
		username = target.Username
	} else {
		userID = i.Member.User.ID
		username = displayName(i.Member, i.Member.User)
	}

	streak, err := b.db.GetUserStreak(ctx, userID)
	if err != nil {
		respondEphemeral(s, i, "Error fetching streak.")
		return
	}
	if streak == 0 {
		respondEphemeral(s, i, fmt.Sprintf("**%s** has no active streak. Get riding! 🚴", username))
		return
	}
	respondEphemeral(s, i, fmt.Sprintf("🔥 **%s** is on a **%d day** streak!", username, streak))
}

func (b *Bot) handleSetUnit(ctx context.Context, s *discordgo.Session, i *discordgo.InteractionCreate) {
	unit := i.ApplicationCommandData().Options[0].StringValue()
	if err := b.db.SetUserPreference(ctx, i.Member.User.ID, i.GuildID, unit); err != nil {
		respondEphemeral(s, i, "Error saving preference.")
		return
	}
	respondEphemeral(s, i, fmt.Sprintf("✅ Your stats will now show in **%s**.", unit))
}