//
//  InsightStrip.swift
//  Prisme
//
//  Author: Simon-Pierre Boucher <contact@spboucher.ai>
//

import SwiftUI

/// The understanding strip: after a page settles, Prisme shows what it
/// read — instantly and deterministically (reading time, structure), then
/// enriched with the page kind and essence when the local model delivers.
/// This is the thesis made visible ("chaque page est comprise avant d'être
/// affichée") without the user hunting for a button. One tap opens the
/// reader; the × dismisses it for this page. Never a popup, never modal.
struct InsightStrip: View {
    let insight: PageInsight
    let digest: PageDigest?
    let accent: Color
    let onRead: () -> Void
    let onDismiss: () -> Void

    /// Single tint for generated content, everywhere in the app (§7).
    private static let generated = Color(red: 0.55, green: 0.36, blue: 0.96)

    var body: some View {
        HStack(spacing: Spacing.m) {
            Button(action: onRead) {
                HStack(spacing: Spacing.m) {
                    Image(systemName: "doc.plaintext")
                        .font(.subheadline.weight(.semibold))
                        .foregroundStyle(accent)

                    VStack(alignment: .leading, spacing: 2) {
                        Text(headline)
                            .font(.footnote.weight(.semibold))
                            .foregroundStyle(.primary)
                        if let gist = digest?.gist, !gist.isEmpty {
                            HStack(alignment: .top, spacing: Spacing.xs) {
                                Image(systemName: "sparkles")
                                    .font(.caption2)
                                    .padding(.top, 2)
                                Text(gist)
                                    .font(.caption)
                                    .italic()
                                    .lineLimit(2)
                            }
                            .foregroundStyle(Self.generated)
                        }
                    }

                    Spacer(minLength: Spacing.s)

                    Text("Lire")
                        .font(.footnote.weight(.semibold))
                        .foregroundStyle(.white)
                        .padding(.horizontal, Spacing.m)
                        .padding(.vertical, Spacing.xs + 2)
                        .background(accent, in: Capsule())
                }
                .contentShape(Rectangle())
            }
            .buttonStyle(.plain)
            .accessibilityIdentifier("insight.read")

            Button(action: onDismiss) {
                Image(systemName: "xmark")
                    .font(.caption.bold())
                    .foregroundStyle(.secondary)
                    .frame(width: 28, height: 28)
                    .contentShape(Circle())
            }
            .buttonStyle(.plain)
            .accessibilityIdentifier("insight.dismiss")
        }
        .padding(.horizontal, Spacing.l)
        .padding(.vertical, Spacing.m)
        .glassEffect(.regular, in: RoundedRectangle(cornerRadius: Radius.l))
    }

    private var headline: String {
        var parts: [String] = []
        if let kind = digest?.kind {
            parts.append(kind.label)
        }
        parts.append("~\(insight.readingMinutes) min de lecture")
        if digest == nil, insight.sectionCount > 1 {
            parts.append("\(insight.sectionCount) sections")
        }
        return parts.joined(separator: " · ")
    }
}