using Microsoft.EntityFrameworkCore;
using PowderCoating.Core.Entities;

namespace PowderCoating.Infrastructure.Services;

public partial class SeedDataService
{
    /// <summary>
    /// Seeds 75 realistic powder coating quotes spread across seven item categories
    /// (automotive wheels, industrial, architectural, fitness, marine, furniture, misc)
    /// with a realistic status distribution: Draft (8), Sent (12), Approved (35),
    /// Rejected (10), and Expired (10).
    /// </summary>
    /// <remarks>
    /// <para>
    /// Idempotency: returns 0 immediately if any non-deleted quotes already exist for
    /// this company, preventing duplicate quote sets on repeated seed runs.
    /// </para>
    /// <para>
    /// Quote numbers follow the production format <c>QT-YYMM-####</c>. The seeder scans
    /// existing numbers with the current month prefix and starts its sequence above the
    /// current maximum so seeded quotes never collide with real quotes created in the
    /// same month.
    /// </para>
    /// <para>
    /// Pricing is deliberately simple (sqft × $8.50 + variance) rather than running through
    /// <c>IPricingCalculationService</c> — this avoids a dependency on company operating cost
    /// config that may not yet be populated when seed runs.
    /// </para>
    /// <para>
    /// Tax-exempt customers automatically receive a 0 % tax rate (matching the production
    /// behaviour in <c>QuotesController</c>). Rush fees (15 %) are added every 12th quote.
    /// </para>
    /// <para>
    /// The method requires that customers and quote-status lookup rows already exist for the
    /// company; it returns 0 if either dependency is missing so that the overall seed
    /// operation degrades gracefully rather than throwing.
    /// </para>
    /// </remarks>
    /// <param name="company">The tenant company to seed quotes for.</param>
    /// <returns>Number of quotes inserted, or 0 if already seeded or dependencies are missing.</returns>
    private async Task<int> SeedQuotesAsync(Company company)
    {
        var existingCount = await _context.Set<Quote>()
            .IgnoreQueryFilters()
            .CountAsync(q => q.CompanyId == company.Id && !q.IsDeleted);

        if (existingCount > 0)
            return 0;

        var quoteStatuses = await _context.Set<QuoteStatusLookup>()
            .IgnoreQueryFilters()
            .Where(s => s.CompanyId == company.Id)
            .ToDictionaryAsync(s => s.StatusCode, s => s.Id);

        if (quoteStatuses.Count == 0)
            return 0;

        // Load all commercial customers
        var customers = await _context.Set<Customer>()
            .IgnoreQueryFilters()
            .Where(c => c.CompanyId == company.Id && c.IsCommercial && !c.IsDeleted)
            .OrderBy(c => c.Id)
            .ToListAsync();

        if (customers.Count == 0)
            return 0;

        var preparedByUser = await _userManager.Users
            .Where(u => u.CompanyId == company.Id)
            .FirstOrDefaultAsync();

        var now = DateTime.UtcNow;

        // Avoid duplicate quote numbers
        var prefix = $"QT-{now:yy}{now.Month:D2}-";
        var existing = await _context.Set<Quote>()
            .IgnoreQueryFilters()
            .Where(q => q.QuoteNumber.StartsWith(prefix))
            .Select(q => q.QuoteNumber)
            .ToListAsync();
        var maxNum = 0;
        foreach (var n in existing)
            if (n.Length >= 12 && int.TryParse(n.Substring(8, 4), out var x) && x > maxNum) maxNum = x;
        var seq = maxNum + 1;

        // ── Data arrays for varied, realistic content ─────────────────────────

        // Returns an array of realistic item descriptions for a given category bucket (0–6).
        // Using a local static function keeps the description data close to where it is
        // consumed and avoids polluting the partial class with per-seeder detail arrays.
        static string[] ItemDescs(int category) => category switch
        {
            0 => new[] {
                "18\" Aluminum Wheels — Matte Black",
                "17\" Steel Wheels — Gloss White",
                "20\" Alloy Wheels — Satin Silver",
                "16\" Chrome Replica Wheels — Gloss Black",
                "Motorcycle Frame — Flat Black",
                "Motorcycle Swingarm & Forks — Gloss Black",
                "Exhaust Headers — High-Temp Flat Black",
                "Intake Manifold — Wrinkle Red",
                "Valve Covers — Gloss Red",
                "Brake Calipers — Gloss Yellow" },
            1 => new[] {
                "Steel Shelving Units (10-shelf set)",
                "Industrial Equipment Frame",
                "Machine Guard Panels",
                "Conveyor Frame Sections",
                "Heavy Equipment Brackets",
                "Pump Housing Assembly",
                "Control Panel Enclosure",
                "Storage Rack System",
                "Scissor Lift Platform",
                "Compressor Tank" },
            2 => new[] {
                "Aluminum Window Frames (set of 8)",
                "Steel Handrail System — 40 ft",
                "Wrought Iron Fence Panels (6-panel set)",
                "Entry Gate — Custom Design",
                "Structural Steel Columns (set of 4)",
                "Balcony Railing — Satin Black",
                "Steel Door Frames (3 units)",
                "Architectural Steel Beams",
                "Decorative Ironwork — Stair Baluster",
                "Aluminum Storefront Frame" },
            3 => new[] {
                "Commercial Gym Equipment Frame",
                "Weight Rack & Benches",
                "Outdoor Playground Equipment Parts",
                "Bicycle Frame — Gloss Blue",
                "BMX Frame Set — Candy Red" },
            4 => new[] {
                "Boat Trailer Frame — Marine Grade",
                "Aluminum Dock Cleats & Hardware",
                "Outboard Motor Bracket",
                "Marine Fuel Tank Brackets" },
            5 => new[] {
                "Restaurant Chair Frames (set of 20)",
                "Steel Dining Table Bases (set of 8)",
                "Patio Furniture Set — 6 Pieces",
                "Café Chairs — Hammered Bronze (12-pc)",
                "Commercial Bar Stools (set of 10)" },
            _ => new[] {
                "Custom Steel Parts — Batch Order",
                "Agricultural Equipment Panels",
                "Traffic Sign Frames (set of 15)",
                "Utility Trailer Hitch Assembly",
                "Solar Panel Mounting Brackets" }
        };

        // Returns finish color, prep flags, estimated minutes, and surface area for item index i.
        // Cycling modulo 9 ensures variety across all 75 quotes without requiring a large lookup table.
        static (string color, bool sandblast, bool mask, int minutes, decimal sqft) ItemSpec(int i) => (i % 9) switch
        {
            0 => ("Matte Black",       true,  false, 45,  12.0m),
            1 => ("Gloss White",       false, false, 30,  8.5m),
            2 => ("Satin Silver",      true,  true,  60,  15.0m),
            3 => ("Candy Red",         false, true,  35,  9.0m),
            4 => ("Textured Gray",     true,  false, 50,  18.0m),
            5 => ("Gloss Black",       true,  false, 40,  11.0m),
            6 => ("Hammered Bronze",   false, false, 55,  20.0m),
            7 => ("Satin Graphite",    true,  true,  65,  25.0m),
            _ => ("Flat Black",        true,  false, 35,  10.0m)
        };

        // Maps quote index to a status code following the distribution plan above.
        // APPROVED is the majority (35/75) to give SeedJobsAsync enough approved quotes to link jobs to.
        static string StatusFor(int i) => i switch
        {
            < 8  => "DRAFT",
            < 20 => "SENT",
            < 55 => "APPROVED",
            < 65 => "REJECTED",
            _    => "EXPIRED"
        };

        var quotes = new List<Quote>();

        for (int i = 0; i < 75; i++)
        {
            var customer  = customers[i % customers.Count];
            var statusCode = StatusFor(i);

            // Spread creation dates over the past 90 days; older first
            var daysAgo    = 90 - (int)(i * 1.2);
            var quoteDate  = now.AddDays(-daysAgo);
            var expireDate = quoteDate.AddDays(30);

            var category  = i % 7;
            var descs     = ItemDescs(category);
            var itemCount = 1 + (i % 3);

            var items = new List<QuoteItem>();
            for (int j = 0; j < itemCount; j++)
            {
                var desc          = descs[(i + j) % descs.Length];
                var (color, sand, mask, mins, sqft) = ItemSpec(i + j);
                var qty           = 1 + (j % 4);
                // Unit price scales with surface area and adds a modest multiplier per customer tier
                var tierMult      = 1m + ((customer.PricingTier?.DiscountPercent ?? 0m) / 100m * -1m);
                var unitPrice     = Math.Round(sqft * 8.50m * tierMult + (i % 5) * 4.5m, 2);

                items.Add(new QuoteItem
                {
                    Description         = desc,
                    Quantity            = qty,
                    SurfaceAreaSqFt     = sqft * qty,
                    UnitPrice           = unitPrice,
                    TotalPrice          = unitPrice * qty,
                    RequiresSandblasting = sand,
                    RequiresMasking     = mask,
                    EstimatedMinutes    = mins,
                    Complexity          = (i % 4) switch { 0 => "Simple", 1 => "Moderate", 2 => "Complex", _ => "Simple" },
                    Notes               = j == 0 && i % 5 == 0 ? $"{color} finish requested" : null,
                    CompanyId           = company.Id,
                    CreatedAt           = quoteDate
                });
            }

            var subtotal       = items.Sum(it => it.TotalPrice);
            var discountPct    = customer.PricingTier?.DiscountPercent ?? 0m;
            var discountAmt    = Math.Round(subtotal * discountPct / 100m, 2);
            var afterDiscount  = subtotal - discountAmt;
            var taxPct         = customer.IsTaxExempt ? 0m : 7.5m;
            var taxAmt         = Math.Round(afterDiscount * taxPct / 100m, 2);
            var rushFee        = i % 12 == 0 ? Math.Round(afterDiscount * 0.15m, 2) : 0m;
            var total          = afterDiscount + taxAmt + rushFee;

            var quote = new Quote
            {
                QuoteNumber       = $"{prefix}{seq:D4}",
                CustomerId        = customer.Id,
                PreparedById      = preparedByUser?.Id,
                QuoteStatusId     = quoteStatuses[statusCode],
                IsCommercial      = customer.IsCommercial,
                IsRushJob         = i % 12 == 0,
                QuoteDate         = quoteDate,
                ExpirationDate    = expireDate,
                SentDate          = statusCode != "DRAFT"     ? quoteDate.AddDays(1)  : null,
                ApprovedDate      = statusCode == "APPROVED"  ? quoteDate.AddDays(4)  : null,
                ItemsSubtotal     = subtotal,
                SubTotal          = subtotal,
                DiscountPercent   = discountPct,
                DiscountAmount    = discountAmt,
                TaxPercent        = taxPct,
                TaxAmount         = taxAmt,
                RushFee           = rushFee,
                Total             = total,
                Description       = $"Powder coating services — {descs[i % descs.Length].Split('—')[0].Trim()}",
                Terms             = customer.PaymentTerms ?? "Net 30",
                Notes             = i % 7 == 0  ? "Customer requested color sample before full run." :
                                    i % 13 == 0 ? "Rush turnaround requested — 3 business days." : null,
                CustomerPO        = i % 2 == 0  ? $"PO-{30000 + i}" : null,
                RequiresDeposit   = i % 4 == 0,
                DepositPercent    = i % 4 == 0 ? 50m : 0m,
                QuoteItems        = items,
                CompanyId         = company.Id,
                CreatedAt         = quoteDate,
                UpdatedAt         = statusCode == "DRAFT" ? quoteDate : quoteDate.AddDays(1)
            };

            quotes.Add(quote);
            seq++;
        }

        await _context.Set<Quote>().AddRangeAsync(quotes);
        await _context.SaveChangesAsync();

        return quotes.Count;
    }
}