defmodule UpiSettlement.Fixtures.RealQrTransactions do
  @moduledoc """
  Real transaction fixtures from Mercury PSP platform (May 2026).

  Captures actual transaction patterns:
  - Static QR: Mercury Static Restaurant (0.00 AED initial, actual amounts entered at payment)
  - Dynamic QR: Dubai Fine Dining (AED 2.22 → ₹50.00)
  - Corridor: UAE international payments
  """

  # ============================================================================
  # MERCHANT CREATION FUNCTIONS (Create fresh test merchants)
  # ============================================================================

  @doc """
  Creates a test merchant with static QR enabled and returns its ID.
  """
  def get_merchant_for_static_qr do
    unique_id = :erlang.unique_integer([:positive]) |> to_string()
    attrs = %{
      mid: "STQR#{String.slice(unique_id, 0, 11)}",
      tid: "T001",
      status: "ACTIVE",
      qr_enabled: true
    }
    merchant =
      %UpiCore.Merchants.Merchant{}
      |> UpiCore.Merchants.Merchant.changeset(attrs)
      |> UpiCore.Repo.insert!()
    merchant.id
  end

  @doc """
  Creates a test merchant with dynamic QR enabled and returns its ID.
  """
  def get_merchant_for_dynamic_qr do
    unique_id = :erlang.unique_integer([:positive]) |> to_string()
    attrs = %{
      mid: "DYQR#{String.slice(unique_id, 0, 11)}",
      tid: "T001",
      status: "ACTIVE",
      dynamic_qr_enabled: true
    }
    merchant =
      %UpiCore.Merchants.Merchant{}
      |> UpiCore.Merchants.Merchant.changeset(attrs)
      |> UpiCore.Repo.insert!()
    merchant.id
  end

  # ============================================================================
  # MERCHANT ATTRIBUTE MAPS (converted to keyword lists for insertion)
  # ============================================================================

  def static_qr_merchant_attrs do
    [
      mid: "MERC_STATIC_001",
      tid: "T001",
      status: "active"
    ]
  end

  def dynamic_qr_merchant_attrs do
    [
      mid: "MERC_DYN_001",
      tid: "T001",
      status: "active"
    ]
  end

  # Legacy map format for reference/testing
  def static_qr_merchant do
    %{
      name: "Mercury Static Restaurant",
      vpa: "mercury.static@upi",
      merchant_id: "MERC_STATIC_001",
      status: "active",
      settlement_frequency: "T+1",
      fund_transfer_days: 2,
      qr_mode: "02"  # STATIC_SECURE
    }
  end

  def dynamic_qr_merchant do
    %{
      name: "Dubai Fine Dining",
      vpa: "dubai.dining@upi",
      merchant_id: "MERC_DYN_001",
      status: "active",
      settlement_frequency: "T+1",
      fund_transfer_days: 2,
      qr_mode: "16"  # DYNAMIC_SECURE
    }
  end

  # ============================================================================
  # STATIC QR TRANSACTIONS (Mercury Static Restaurant)
  # Real transaction IDs from May 14-20, 2026
  # ============================================================================

  # Raw map format for reference
  def static_qr_txn_1_map do
    %{
      utxn_id: "MER7964aa502ecb078f444cb84c0d5e9e49",
      payer_vpa: "tester2@upi",
      payee_vpa: "mercury.static@upi",
      rrn: "000000000001",
      amount: Decimal.new("0"),
      status: "success",
      inserted_at: DateTime.from_naive!(NaiveDateTime.new!(~D[2026-05-20], ~T[12:49:00]), "Etc/UTC"),
      corridor: "UAE",
      initiation_mode: "02",  # STATIC_SECURE
      merchant_id: "MERC_STATIC_001"
    }
  end

  # Keyword list format for insert_transaction
  def static_qr_txn_1(merchant_id \\ "MERC_STATIC_001") do
    [
      merchant_id: merchant_id,
      inr_amount: Decimal.new("0"),
      status: "success",
      inserted_at: DateTime.from_naive!(NaiveDateTime.new!(~D[2026-05-20], ~T[12:49:00]), "Etc/UTC")
    ]
  end

  def static_qr_txn_2(merchant_id) do
    [
      merchant_id: merchant_id,
      inr_amount: Decimal.new("0"),
      status: "success",
      inserted_at: DateTime.from_naive!(NaiveDateTime.new!(~D[2026-05-14], ~T[01:19:00]), "Etc/UTC")
    ]
  end

  def static_qr_txn_3(merchant_id) do
    [
      merchant_id: merchant_id,
      inr_amount: Decimal.new("0"),
      status: "success",
      inserted_at: DateTime.from_naive!(NaiveDateTime.new!(~D[2026-05-14], ~T[12:40:00]), "Etc/UTC")
    ]
  end

  def static_qr_txn_4(merchant_id) do
    [
      merchant_id: merchant_id,
      inr_amount: Decimal.new("0"),
      status: "success",
      inserted_at: DateTime.from_naive!(NaiveDateTime.new!(~D[2026-05-14], ~T[11:04:00]), "Etc/UTC")
    ]
  end

  def static_qr_txn_5(merchant_id) do
    [
      merchant_id: merchant_id,
      inr_amount: Decimal.new("0"),
      status: "success",
      inserted_at: DateTime.from_naive!(NaiveDateTime.new!(~D[2026-05-14], ~T[10:59:00]), "Etc/UTC")
    ]
  end

  # ============================================================================
  # DYNAMIC QR TRANSACTIONS (Dubai Fine Dining)
  # Real transaction IDs from May 14-15, 2026
  # AED 2.22 → ₹50.00 conversion
  # ============================================================================

  def dynamic_qr_txn_1(merchant_id) do
    [
      merchant_id: merchant_id,
      inr_amount: Decimal.new("50.00"),
      status: "success",
      inserted_at: DateTime.from_naive!(NaiveDateTime.new!(~D[2026-05-14], ~T[10:41:00]), "Etc/UTC")
    ]
  end

  def dynamic_qr_txn_2(merchant_id) do
    [
      merchant_id: merchant_id,
      inr_amount: Decimal.new("50.00"),
      status: "success",
      inserted_at: DateTime.from_naive!(NaiveDateTime.new!(~D[2026-05-14], ~T[10:32:00]), "Etc/UTC")
    ]
  end

  def dynamic_qr_txn_3(merchant_id) do
    [
      merchant_id: merchant_id,
      inr_amount: Decimal.new("50.00"),
      status: "success",
      inserted_at: DateTime.from_naive!(NaiveDateTime.new!(~D[2026-05-15], ~T[05:28:00]), "Etc/UTC")
    ]
  end

  def dynamic_qr_txn_4(merchant_id) do
    [
      merchant_id: merchant_id,
      inr_amount: Decimal.new("50.00"),
      status: "success",
      inserted_at: DateTime.from_naive!(NaiveDateTime.new!(~D[2026-05-14], ~T[10:08:00]), "Etc/UTC")
    ]
  end

  # ============================================================================
  # STATIC QR WITH VALIDATIONS (for test scenarios)
  # ============================================================================

  def static_qr_with_expiry_valid do
    %{
      qr_id: "QR_STATIC_VALID_001",
      merchant_id: "MERC_STATIC_001",
      initiation_mode: "02",
      status: "active",
      max_usage_count: 10000,
      usage_count: 5000,
      expires_at: DateTime.add(DateTime.utc_now() |> DateTime.truncate(:second), 86400 * 30),  # 30 days from now
      created_at: DateTime.utc_now() |> DateTime.truncate(:second)
    }
  end

  def static_qr_with_expiry_expired do
    %{
      qr_id: "QR_STATIC_EXPIRED_001",
      merchant_id: "MERC_STATIC_001",
      initiation_mode: "02",
      status: "active",
      max_usage_count: 10000,
      usage_count: 5000,
      expires_at: DateTime.add(DateTime.utc_now() |> DateTime.truncate(:second), -86400),  # 1 day ago
      created_at: DateTime.utc_now() |> DateTime.truncate(:second)
    }
  end

  def static_qr_with_usage_limit_exceeded do
    %{
      qr_id: "QR_STATIC_LIMIT_001",
      merchant_id: "MERC_STATIC_001",
      initiation_mode: "02",
      status: "active",
      max_usage_count: 100,
      usage_count: 100,  # At limit
      expires_at: DateTime.add(DateTime.utc_now() |> DateTime.truncate(:second), 86400 * 30),
      created_at: DateTime.utc_now() |> DateTime.truncate(:second)
    }
  end

  def static_qr_inactive do
    %{
      qr_id: "QR_STATIC_INACTIVE_001",
      merchant_id: "MERC_STATIC_001",
      initiation_mode: "02",
      status: "inactive",  # Deactivated
      max_usage_count: 10000,
      usage_count: 5000,
      expires_at: DateTime.add(DateTime.utc_now() |> DateTime.truncate(:second), 86400 * 30),
      created_at: DateTime.utc_now() |> DateTime.truncate(:second)
    }
  end

  # ============================================================================
  # FEE CONFIGURATION
  # ============================================================================

  def fee_config_standard do
    %{
      interchange_rate: Decimal.new("0.0015"),     # 0.15%
      switching_flat: Decimal.new("0.25"),         # ₹0.25 per transaction
      psp_fee_rate: Decimal.new("0.005"),          # 0.50%
      gst_rate: Decimal.new("0.18")                # 18% on PSP fee
    }
  end

  def fee_config_static_qr do
    %{
      interchange_rate: Decimal.new("0.0010"),     # 0.10% (lower)
      switching_flat: Decimal.new("0.15"),         # ₹0.15 (lower)
      psp_fee_rate: Decimal.new("0.0045"),         # 0.45% (margin increase)
      gst_rate: Decimal.new("0.18")                # 18% on PSP fee
    }
  end

  # ============================================================================
  # FX RATES
  # ============================================================================

  def fx_rate_uae_inr do
    %{
      from_currency: "AED",
      to_currency: "INR",
      rate: Decimal.new("22.5"),  # 1 AED = ₹22.50
      effective_date: ~D[2026-05-14],
      expires_at: ~D[2026-06-14]
    }
  end

  # ============================================================================
  # HELPER FUNCTIONS FOR NTSL CALCULATION
  # ============================================================================

  @doc "Calculate NTSL with given fee config"
  def calculate_net_amount(gross_amount, txn_count, fee_config \\ nil) do
    config = fee_config || fee_config_standard()

    gross = Decimal.new(to_string(gross_amount))
    interchange = Decimal.mult(gross, config.interchange_rate) |> Decimal.round(4)
    switching = Decimal.mult(config.switching_flat, Decimal.new(txn_count)) |> Decimal.round(4)
    psp_fee = Decimal.mult(gross, config.psp_fee_rate) |> Decimal.round(4)
    gst = Decimal.mult(psp_fee, config.gst_rate) |> Decimal.round(4)

    net =
      gross
      |> Decimal.sub(interchange)
      |> Decimal.sub(switching)
      |> Decimal.sub(psp_fee)
      |> Decimal.sub(gst)
      |> Decimal.round(2)

    %{
      gross: gross,
      interchange_fee: interchange,
      switching_fee: switching,
      psp_fee: psp_fee,
      gst: gst,
      net: net
    }
  end

  @doc "Example: Static QR batch from Mercury (5 txns, ₹0 each)"
  def static_qr_batch_mercury(merchant_id) do
    [
      static_qr_txn_1(merchant_id),
      static_qr_txn_2(merchant_id),
      static_qr_txn_3(merchant_id),
      static_qr_txn_4(merchant_id),
      static_qr_txn_5(merchant_id)
    ]
  end

  @doc "Example: Dynamic QR batch from Dubai Fine Dining (4 txns, ₹50 each)"
  def dynamic_qr_batch_dubai(merchant_id) do
    [
      dynamic_qr_txn_1(merchant_id),
      dynamic_qr_txn_2(merchant_id),
      dynamic_qr_txn_3(merchant_id),
      dynamic_qr_txn_4(merchant_id)
    ]
  end
end