//
//  NewRuleSheet.swift
//  Severed
//

import SwiftData
import SwiftUI

/// "New Rule": the three rule-type cards up top, then the preset gallery.
/// Picking either one morphs the sheet into the editor; committing saves the
/// rule and closes the sheet.
struct NewRuleSheet: View {
    @Environment(\.dismiss) private var dismiss
    @Environment(\.modelContext) private var modelContext
    @State private var pendingDraft: RuleDraft?

    var body: some View {
        Group {
            if let pendingDraft {
                RuleEditorView(
                    mode: .create,
                    draft: pendingDraft,
                    onBack: { self.pendingDraft = nil },
                    onCommit: { draft in
                        modelContext.insert(draft.makeRule())
                        dismiss()
                    }
                )
            } else {
                chooser
            }
        }
        .background(Theme.background)
    }

    private var chooser: some View {
        VStack(spacing: 0) {
            HStack {
                CircleIconButton(systemImage: "xmark") { dismiss() }
                    .accessibilityIdentifier("closeNewRuleButton")
                Spacer()
            }
            .overlay(
                Text("New Rule")
                    .font(.system(size: 18, weight: .semibold))
            )
            .padding(.horizontal, 20)
            .padding(.top, 18)

            ScrollView {
                VStack(alignment: .leading, spacing: 26) {
                    HStack(spacing: 10) {
                        ForEach(RuleKind.allCases, id: \.self) { kind in
                            kindCard(kind)
                        }
                    }
                    ForEach(RulePresetSection.all) { section in
                        presetSection(section)
                    }
                }
                .padding(.horizontal, 20)
                .padding(.top, 20)
                .padding(.bottom, 30)
            }
        }
        .foregroundStyle(.white)
    }

    private func kindCard(_ kind: RuleKind) -> some View {
        Button {
            pendingDraft = RuleDraft(kind: kind)
        } label: {
            VStack(spacing: 8) {
                Image(systemName: kind.symbolName)
                    .font(.system(size: 20, weight: .semibold))
                    .foregroundStyle(Theme.accent)
                    .frame(height: 26)
                Text(kind.displayName)
                    .font(.system(size: 14, weight: .semibold))
                Text(kind.exampleText)
                    .font(.system(size: 11))
                    .foregroundStyle(Theme.textTertiary)
            }
            .frame(maxWidth: .infinity)
            .padding(.vertical, 18)
            .background(Theme.surface, in: RoundedRectangle(cornerRadius: 18))
        }
        .buttonStyle(.plain)
        .accessibilityIdentifier("ruleKind-\(kind.rawValue)")
    }

    private func presetSection(_ section: RulePresetSection) -> some View {
        VStack(alignment: .leading, spacing: 4) {
            Text(section.title)
                .font(.system(size: 18, weight: .bold))
            Text(section.subtitle)
                .font(.system(size: 13))
                .foregroundStyle(Theme.textSecondary)
            LazyVGrid(
                columns: [GridItem(.flexible(), spacing: 12), GridItem(.flexible())],
                spacing: 12
            ) {
                ForEach(section.presets) { preset in
                    presetCard(preset)
                }
            }
            .padding(.top, 12)
        }
    }

    private func presetCard(_ preset: RulePreset) -> some View {
        Button {
            pendingDraft = RuleDraft(preset: preset)
        } label: {
            VStack(alignment: .leading, spacing: 4) {
                HStack {
                    RuleIconPair(kind: .schedule)
                    Spacer()
                }
                Spacer()
                Image(systemName: preset.symbolName)
                    .font(.system(size: 22, weight: .semibold))
                    .foregroundStyle(.white.opacity(0.8))
                    .padding(.bottom, 8)
                Text(preset.schedule.timeRangeLabel)
                    .font(.system(size: 12))
                    .foregroundStyle(Theme.textSecondary)
                Text(preset.name)
                    .font(.system(size: 16, weight: .semibold))
                HStack {
                    Text("Block")
                        .font(.system(size: 12))
                        .foregroundStyle(Theme.textSecondary)
                    Spacer()
                    Image(systemName: "plus.circle.fill")
                        .font(.system(size: 22))
                        .foregroundStyle(.white.opacity(0.85))
                }
            }
            .padding(14)
            .frame(height: 190)
            .background(
                LinearGradient(
                    colors: [preset.gradientTop, preset.gradientBottom],
                    startPoint: .top, endPoint: .bottom
                ),
                in: RoundedRectangle(cornerRadius: 20)
            )
            .overlay(
                RoundedRectangle(cornerRadius: 20)
                    .strokeBorder(.white.opacity(0.08), lineWidth: 1)
            )
        }
        .buttonStyle(.plain)
        .accessibilityIdentifier("preset-\(preset.id)")
    }
}