package templates

import (
	"fmt"
	"time"

	"veola/internal/db"
	"veola/internal/models"
)

type DashboardData struct {
	Page
	Stats         *db.DashboardStats
	RecentResults []ResultRow
	RecentAlerts  []AlertRow
	// Budget surface, shown to every signed-in user (Apify calls cost money).
	ApifyToday       int
	ApifyMonth       int
	ApifyCostPerCall float64
	MonthlyBudget    float64
	EbayToday        int
	EbayLimit        int
}

// ApifyMonthCost is the estimated month-to-date Apify spend in USD.
func (d DashboardData) ApifyMonthCost() float64 {
	return float64(d.ApifyMonth) * d.ApifyCostPerCall
}

// BudgetPercent is month-to-date spend as a percent of the monthly budget,
// clamped to [0,100]. Zero when no budget is set.
func (d DashboardData) BudgetPercent() int {
	if d.MonthlyBudget <= 0 {
		return 0
	}
	p := int(d.ApifyMonthCost() / d.MonthlyBudget * 100)
	if p < 0 {
		return 0
	}
	if p > 100 {
		return 100
	}
	return p
}

// BudgetOver reports whether estimated spend has exceeded the monthly budget.
func (d DashboardData) BudgetOver() bool {
	return d.MonthlyBudget > 0 && d.ApifyMonthCost() > d.MonthlyBudget
}

type ResultRow struct {
	ItemID   int64
	ItemName string
	Title    string
	Price    *float64
	Currency string
	Source   string
	URL      string
	FoundAt  time.Time
	Alerted  bool
}

type AlertRow struct {
	ItemName string
	Price    *float64
	Currency string
	FoundAt  time.Time
}

// DashboardBody is the self-refreshing inner block. It is both the initial
// render target (inside Layout) and the response to /dashboard/refresh, so the
// hx-swap="outerHTML" on its root div replaces it with a fresh copy of itself.
// GetDashboardRefresh must render THIS, not Dashboard — rendering the full
// Layout would inject a nested page (and a duplicate sidebar) into the div.
templ DashboardBody(d DashboardData) {
	<div hx-get="/dashboard/refresh" hx-trigger="every 60s" hx-swap="outerHTML">
		<h1 class="text-3xl font-semibold mb-6">Dashboard</h1>
		<div class="grid grid-cols-2 md:grid-cols-4 gap-4 mb-6">
			@statCard("Total Items", fmt.Sprintf("%d", d.Stats.TotalItems), "")
			@statCard("Active", fmt.Sprintf("%d", d.Stats.ActiveItems), "")
			@statCard("Results Today", fmt.Sprintf("%d", d.Stats.ResultsToday), "")
			@statCard("Alerts Today", fmt.Sprintf("%d", d.Stats.AlertsToday), "")
		</div>
		<div class="grid md:grid-cols-2 gap-4 mb-6">
			<div class="v-card p-5">
				<div class="v-muted text-sm uppercase tracking-wide">Potential Spend</div>
				<div class="font-mono text-4xl mt-2" data-countup>{ fmt.Sprintf("$%.2f", d.Stats.PotentialSpend) }</div>
				<div class="v-muted text-sm mt-1">across { fmt.Sprintf("%d", d.Stats.PricedItemCount) } items</div>
				if d.Stats.UnpricedCount > 0 {
					<div class="v-muted text-xs mt-1">{ fmt.Sprintf("%d items not yet priced.", d.Stats.UnpricedCount) }</div>
				}
			</div>
			<div class="v-card p-5">
				<div class="v-muted text-sm uppercase tracking-wide">Money Saved</div>
				<div class="font-mono text-4xl mt-2 v-price-deal" data-countup>{ fmt.Sprintf("$%.2f", d.Stats.MoneySaved) }</div>
				<div class="v-muted text-sm mt-1">across { fmt.Sprintf("%d", d.Stats.SavedItemCount) } items</div>
			</div>
		</div>
		<div class="v-card p-5 mb-6">
			<div class="flex items-center justify-between mb-3">
				<h2 class="font-semibold">API Usage and Budget</h2>
				<span class="v-muted text-xs">Apify runs cost credits. Visible to everyone.</span>
			</div>
			<div class="grid grid-cols-2 md:grid-cols-4 gap-4">
				<div>
					<div class="v-muted text-xs uppercase tracking-wide">Apify (month)</div>
					<div class="font-mono text-2xl mt-1">{ fmt.Sprintf("%d", d.ApifyMonth) }</div>
					if d.ApifyCostPerCall > 0 {
						<div class="v-muted text-xs mt-1">{ fmt.Sprintf("~$%.2f est.", d.ApifyMonthCost()) }</div>
					}
				</div>
				<div>
					<div class="v-muted text-xs uppercase tracking-wide">Apify (today)</div>
					<div class="font-mono text-2xl mt-1">{ fmt.Sprintf("%d", d.ApifyToday) }</div>
				</div>
				<div>
					<div class="v-muted text-xs uppercase tracking-wide">eBay (today)</div>
					if d.EbayLimit > 0 {
						<div class="font-mono text-2xl mt-1">{ fmt.Sprintf("%d / %d", d.EbayToday, d.EbayLimit) }</div>
					} else {
						<div class="font-mono text-2xl mt-1">{ fmt.Sprintf("%d", d.EbayToday) }</div>
					}
				</div>
				if d.MonthlyBudget > 0 {
					<div>
						<div class="v-muted text-xs uppercase tracking-wide">Monthly Budget</div>
						<div class="font-mono text-2xl mt-1">{ fmt.Sprintf("$%.0f", d.MonthlyBudget) }</div>
					</div>
				}
			</div>
			if d.MonthlyBudget > 0 {
				<div class="mt-4">
					<progress class="v-progress w-full" value={ fmt.Sprintf("%d", d.BudgetPercent()) } max="100"></progress>
					<div class="flex justify-between text-xs mt-1">
						<span class="v-muted">{ fmt.Sprintf("%d%% of budget used", d.BudgetPercent()) }</span>
						if d.BudgetOver() {
							<span class="v-price-target">Over budget</span>
						}
					</div>
				</div>
			}
		</div>
		<div class="grid md:grid-cols-2 gap-6">
			<div class="v-card p-5">
				<h2 class="font-semibold mb-3">Recent Results</h2>
				if len(d.RecentResults) == 0 {
					<div class="v-muted text-sm">No results yet.</div>
				} else {
					<table class="v-table">
						<thead>
							<tr><th>Item</th><th>Price</th><th>Source</th><th>Found</th></tr>
						</thead>
						<tbody>
							for _, r := range d.RecentResults {
								<tr>
									<td><a href={ templ.SafeURL(fmt.Sprintf("/items/%d/results", r.ItemID)) }>{ r.ItemName }</a></td>
									<td class="font-mono">{ fmtPrice(r.Price, r.Currency) }</td>
									<td>{ r.Source }</td>
									<td class="v-muted text-sm">{ humanTime(r.FoundAt) }</td>
								</tr>
							}
						</tbody>
					</table>
				}
			</div>
			<div class="v-card p-5">
				<h2 class="font-semibold mb-3">Recent Alerts</h2>
				if len(d.RecentAlerts) == 0 {
					<div class="v-muted text-sm">No alerts sent yet.</div>
				} else {
					<ul class="space-y-2">
						for _, a := range d.RecentAlerts {
							<li class="flex justify-between items-center border-b border-white/10 pb-2">
								<span>{ a.ItemName }</span>
								<span class="font-mono v-price-target">{ fmtPrice(a.Price, a.Currency) }</span>
							</li>
						}
					</ul>
				}
			</div>
		</div>
	</div>
}

templ statCard(label, value, sub string) {
	<div class="v-card p-4">
		<div class="v-muted text-xs uppercase tracking-wide">{ label }</div>
		<div class="font-mono text-3xl mt-1" data-countup>{ value }</div>
		if sub != "" {
			<div class="v-muted text-xs mt-1">{ sub }</div>
		}
	</div>
}

templ Dashboard(d DashboardData) {
	@Layout(d.Page, DashboardBody(d))
}

// Helpers used by multiple templates.

func fmtPrice(p *float64, currency string) string {
	if p == nil {
		return "—"
	}
	sym := currencySymbol(currency)
	return fmt.Sprintf("%s%.2f", sym, *p)
}

func currencySymbol(c string) string {
	switch c {
	case "USD", "":
		return "$"
	case "GBP":
		return "£"
	case "EUR":
		return "€"
	case "JPY":
		return "¥"
	default:
		return c + " "
	}
}

func humanTime(t time.Time) string {
	if t.IsZero() {
		return "—"
	}
	d := time.Since(t)
	switch {
	case d < time.Minute:
		return "just now"
	case d < time.Hour:
		m := int(d.Minutes())
		return fmt.Sprintf("%d minutes ago", m)
	case d < 24*time.Hour:
		h := int(d.Hours())
		return fmt.Sprintf("%d hours ago", h)
	case d < 30*24*time.Hour:
		d2 := int(d.Hours() / 24)
		return fmt.Sprintf("%d days ago", d2)
	default:
		return t.Format("2006-01-02")
	}
}

// Used by item rendering.
var _ = models.Item{}