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
	ImageURL string
	FoundAt  time.Time
	Alerted  bool
}

type AlertRow struct {
	ItemName string
	Title    string
	Price    *float64
	Currency string
	ImageURL 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">
		<header class="mb-10">
			<h1 class="v-page-title">Dashboard</h1>
			<p class="v-page-sub">{ fmt.Sprintf("Watching %d items · %d active", d.Stats.TotalItems, d.Stats.ActiveItems) }</p>
		</header>
		<div class="grid md:grid-cols-2 gap-8 mb-8">
			<div>
				<div class="v-metric-label">Potential spend</div>
				<div class="v-metric-value" data-countup>{ fmt.Sprintf("$%.2f", d.Stats.PotentialSpend) }</div>
				<div class="v-metric-sub">
					{ fmt.Sprintf("across %d priced items", d.Stats.PricedItemCount) }
					if d.Stats.UnpricedCount > 0 {
						{ fmt.Sprintf(" · %d not yet priced", d.Stats.UnpricedCount) }
					}
				</div>
			</div>
			<div>
				<div class="v-metric-label">Money saved</div>
				<div class="v-metric-value v-price-deal" data-countup>{ fmt.Sprintf("$%.2f", d.Stats.MoneySaved) }</div>
				<div class="v-metric-sub">{ fmt.Sprintf("across %d items, vs 30-day average", d.Stats.SavedItemCount) }</div>
			</div>
		</div>
		<hr class="v-rule mb-8"/>
		<div class="grid grid-cols-2 md:grid-cols-4 gap-6 mb-8">
			@statBlock("Total items", fmt.Sprintf("%d", d.Stats.TotalItems))
			@statBlock("Active", fmt.Sprintf("%d", d.Stats.ActiveItems))
			@statBlock("Results today", fmt.Sprintf("%d", d.Stats.ResultsToday))
			@statBlock("Alerts today", fmt.Sprintf("%d", d.Stats.AlertsToday))
		</div>
		<hr class="v-rule mb-8"/>
		<section class="mb-10">
			<div class="flex items-baseline justify-between mb-5">
				<h2 class="v-section-title">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-6">
				<div>
					<div class="v-stat-label">Apify (month)</div>
					<div class="v-stat-value">{ fmt.Sprintf("%d", d.ApifyMonth) }</div>
					if d.ApifyCostPerCall > 0 {
						<div class="v-metric-sub">{ fmt.Sprintf("~$%.2f estimated", d.ApifyMonthCost()) }</div>
					}
				</div>
				<div>
					<div class="v-stat-label">Apify (today)</div>
					<div class="v-stat-value">{ fmt.Sprintf("%d", d.ApifyToday) }</div>
				</div>
				<div>
					<div class="v-stat-label">eBay (today)</div>
					if d.EbayLimit > 0 {
						<div class="v-stat-value">{ fmt.Sprintf("%d / %d", d.EbayToday, d.EbayLimit) }</div>
					} else {
						<div class="v-stat-value">{ fmt.Sprintf("%d", d.EbayToday) }</div>
					}
				</div>
				if d.MonthlyBudget > 0 {
					<div>
						<div class="v-stat-label">Monthly budget</div>
						<div class="v-stat-value">{ fmt.Sprintf("$%.0f", d.MonthlyBudget) }</div>
					</div>
				}
			</div>
			if d.MonthlyBudget > 0 {
				<div class="mt-6 max-w-md">
					<progress class="v-progress w-full" value={ fmt.Sprintf("%d", d.BudgetPercent()) } max="100"></progress>
					<div class="flex justify-between text-xs mt-2">
						<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>
			}
		</section>
		<hr class="v-rule mb-8"/>
		<div class="grid md:grid-cols-2 gap-10">
			<section>
				<h2 class="v-section-title mb-4">Recent results</h2>
				if len(d.RecentResults) == 0 {
					<div class="v-empty">Nothing found yet. Veola is watching.</div>
				} else {
					<ul class="v-feed">
						for _, r := range d.RecentResults {
							<li class="v-feed-row">
								<a href={ templ.SafeURL(fmt.Sprintf("/items/%d/results", r.ItemID)) }>
									@thumb(r.ImageURL, r.Source)
								</a>
								<div class="min-w-0 flex-1">
									<a class="v-feed-name" href={ templ.SafeURL(fmt.Sprintf("/items/%d/results", r.ItemID)) }>{ r.ItemName }</a>
									<div class="v-feed-meta truncate">{ resultMeta(r) }</div>
								</div>
								<div class="font-mono v-feed-price">{ fmtPrice(r.Price, r.Currency) }</div>
							</li>
						}
					</ul>
				}
			</section>
			<section>
				<h2 class="v-section-title mb-4">Recent alerts</h2>
				if len(d.RecentAlerts) == 0 {
					<div class="v-empty">No alerts sent. Nothing has hit target.</div>
				} else {
					<ul class="v-feed">
						for _, a := range d.RecentAlerts {
							<li class="v-feed-row">
								@thumb(a.ImageURL, "")
								<div class="min-w-0 flex-1">
									<div class="v-feed-name truncate">{ a.ItemName }</div>
									if a.Title != "" {
										<div class="v-feed-meta truncate">{ a.Title }</div>
									}
								</div>
								<div class="font-mono v-feed-price v-price-target">{ fmtPrice(a.Price, a.Currency) }</div>
							</li>
						}
					</ul>
				}
			</section>
		</div>
	</div>
}

// thumb renders a product thumbnail, falling back to a quiet placeholder
// (the source initial) when a listing has no image. Marketplace images come
// from an open set of CDNs, which the CSP's img-src allows.
templ thumb(url, source string) {
	if url != "" {
		<img class="v-thumb" src={ url } loading="lazy" alt="" referrerpolicy="no-referrer"/>
	} else {
		<div class="v-thumb v-thumb-empty">{ sourceInitial(source) }</div>
	}
}

// thumbSm is the compact table-row variant of thumb (no source placeholder
// glyph — a plain quiet square when an item has no best-price image yet).
templ thumbSm(url string) {
	if url != "" {
		<img class="v-thumb v-thumb-sm" src={ url } loading="lazy" alt="" referrerpolicy="no-referrer"/>
	} else {
		<div class="v-thumb v-thumb-sm v-thumb-empty"></div>
	}
}

func resultMeta(r ResultRow) string {
	if r.Title != "" {
		return r.Title
	}
	return r.Source + " · " + humanTime(r.FoundAt)
}

func sourceInitial(source string) string {
	if source == "" {
		return ""
	}
	return string([]rune(source)[:1])
}

templ statBlock(label, value string) {
	<div>
		<div class="v-stat-label">{ label }</div>
		<div class="v-stat-value" data-countup>{ value }</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{}