feat(investment): wire Bank/Party, Script Master and Purchase Entry to the backend

- Bank / Party Master and Script Master follow the bank's existing CBS
  screens (address, bank type, GL A/c, RBI code, limit, LEI, counterparty
  bank details; SLR type, auto script code, ISIN, interest rate, issue /
  maturity date, auto period, company details) and save to
  /investment/parties and /investment/scripts. GL dropdowns list enabled
  ASSET detail accounts from the chart of accounts.
- Purchase Entry simplified to the mandatory fields; script details,
  settlement date, last interest date, units, book value, premium/discount,
  accrued interest (30/360 up to the deal date), settlement amount and YTM
  are filled automatically; optional fields sit under "More Details";
  an Accounting Preview shows the GL entry. Save / Retrieve / Drop use
  /investment/purchases and the Holdings register lists saved purchases.
- New InvestmentService for the investment API calls.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/app/investment/bond-investment/bond-investment.component.ts

@@ -6,16 +6,11 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
  */
 
-import { Component } from '@angular/core';
+import { Component, OnInit, inject } from '@angular/core';
 import { CommonModule } from '@angular/common';
 import { FormsModule } from '@angular/forms';
 import { DateDdmmyyyyPickerComponent } from '../date-ddmmyyyy-picker/date-ddmmyyyy-picker.component';
 import {
-  GOVT_SECURITY_HOLDINGS,
-  NON_SLR_HOLDINGS,
-  BOND_HOLDINGS,
-  MUTUAL_FUND_HOLDINGS,
-  ALL_TXNS,
   SCRIPT_MASTER,
   PARTY_MASTER,
   SUBTYPE_MASTER,
@@ -33,6 +28,14 @@ import {
   AUTHORITY_OPTIONS,
   INTEREST_INCOME_GL_MASTER,
   INTEREST_INCOME_GL_BY_TYPE,
+  INVESTMENT_GL_BY_TYPE,
+  INVESTMENT_GL_LOOKUP,
+  INTEREST_RECEIVABLE_GL,
+  SETTLEMENT_BANK_GL_OPTIONS,
+  periodBetween,
+  parseDDMMYYYY,
+  days360,
+  lastHalfYearlyCouponDate,
   InvestmentHolding,
   InvestmentTxn,
   InstrumentType,
@@ -49,6 +52,7 @@ import {
   todayDDMMYYYY
 } from '../investment-data';
 import { exportWorkbook } from '../investment-export';
+import { InvestmentPurchaseDto, InvestmentService, apiErrorMessage, toHolding } from '../investment.service';
 
 type BondType = 'GOVT_SECURITY' | 'NON_SLR' | 'BOND' | 'MUTUAL_FUND';
 type BondTab =
@@ -131,6 +135,13 @@ interface BondPurchaseForm {
   stampDutyAc: string;
 }
 
+interface AccountingPreviewLine {
+  side: 'Dr' | 'Cr';
+  glCode: string;
+  glName: string;
+  amount: number;
+}
+
 interface BondSellForm {
   /** Legacy screen has SELL / REDEEM / MUTUAL FUND SELL radio at the top. */
   mode: 'SELL' | 'REDEEM' | 'MUTUAL_FUND_SELL';
@@ -182,23 +193,67 @@ interface BondSellForm {
     DateDdmmyyyyPickerComponent
   ]
 })
-export class BondInvestmentComponent {
+export class BondInvestmentComponent implements OnInit {
+  private readonly investmentService = inject(InvestmentService);
+
+  /** Script and party dropdowns offer the masters saved in the backend. */
+  ngOnInit(): void {
+    this.investmentService.syncSharedMasters().subscribe({
+      error: (err) => this.toast(`Could not load Script / Party masters: ${apiErrorMessage(err)}`)
+    });
+    this.investmentService.getAssetGlAccounts().subscribe({
+      next: (gls) =>
+        (this.glIdByCode = new Map(
+          gls.map((g) => [
+            g.glCode,
+            g.id
+          ])
+        )),
+      error: (err) => this.toast(`Could not load GL accounts: ${apiErrorMessage(err)}`)
+    });
+    this.loadPurchases();
+  }
+
+  /** GL id for a GL code — the purchase API takes ids, the form works with codes. */
+  private glIdByCode = new Map<string, number>();
+
+  /** The Holdings register and transaction log are the purchases saved in the backend. */
+  private loadPurchases(): void {
+    this.investmentService.getPurchases().subscribe({
+      next: (purchases) => {
+        this.holdings = purchases.map(toHolding);
+        this.txns = purchases.map((d) => this.purchaseTxn(d));
+        this.purchaseForm = this.blankPurchaseForm();
+      },
+      error: (err) => this.toast(`Could not load purchases: ${apiErrorMessage(err)}`)
+    });
+  }
+
+  private purchaseTxn(d: InvestmentPurchaseDto): InvestmentTxn {
+    return {
+      certNo: d.certNo,
+      instrumentType: d.bondType,
+      txnType: 'PURCHASE',
+      voucherNo: `INV/PUR/${d.dealNo}`,
+      txnDate: d.dealDate,
+      amount: d.settlementAmount,
+      particulars: `Purchase Deal ${d.dealNo} - ${d.scriptDesc} - ${d.partyName} [${d.category}]`,
+      glCode: d.investmentGlCode,
+      glName: d.investmentGlName
+    };
+  }
+
   activeTab: BondTab = 'holdings';
+  /** Purchase Entry shows only the mandatory fields; the rest sit under "More Details". */
+  showMoreDetails = false;
+  /** Cert No typed in the Retrieve box (Cert No itself is system-generated and read-only). */
+  retrieveCertNo = '';
   bondType: BondType = 'GOVT_SECURITY';
   asOnDate = todayDDMMYYYY();
 
-  holdings: InvestmentHolding[] = [
-    ...GOVT_SECURITY_HOLDINGS,
-    ...NON_SLR_HOLDINGS,
-    ...BOND_HOLDINGS,
-    ...MUTUAL_FUND_HOLDINGS
-  ];
-  txns: InvestmentTxn[] = ALL_TXNS.filter((t) => ([
-        'GOVT_SECURITY',
-        'NON_SLR',
-        'BOND',
-        'MUTUAL_FUND'
-      ] as InstrumentType[]).includes(t.instrumentType));
+  /** Loaded from the backend (saved purchases) in ngOnInit. */
+  holdings: InvestmentHolding[] = [];
+  txns: InvestmentTxn[] = [];
 
   // Master-driven dropdown sources
   readonly scriptOptions = SCRIPT_MASTER;
@@ -224,6 +279,7 @@ export class BondInvestmentComponent {
 
   purchaseForm: BondPurchaseForm = this.blankPurchaseForm();
   sellForm: BondSellForm = this.blankSellForm();
+  readonly settlementBankOptions = SETTLEMENT_BANK_GL_OPTIONS;
 
   // Redemption Entry
   redeemCertNo = '';
@@ -305,20 +361,37 @@ export class BondInvestmentComponent {
     return INSTRUMENT_LABELS[type];
   }
 
+  /** Preview of the deal number the backend will assign: FY prefix (e.g. 202627) + running number. */
   private nextDealNo(): string {
-    return `2026${String(27000039 + this.holdings.length).padStart(9, '0')}`;
+    const d = parseDDMMYYYY(this.asOnDate);
+    const fyStart = d.getMonth() >= 3 ? d.getFullYear() : d.getFullYear() - 1;
+    const prefix = `${fyStart}${String((fyStart + 1) % 100).padStart(2, '0')}`;
+    const nums = (this.holdings ?? [])
+      .map((h) => h.dealNo)
+      .filter((n): n is string => !!n && n.startsWith(prefix))
+      .map((n) => parseInt(n.slice(prefix.length), 10));
+    return `${prefix}${String((nums.length ? Math.max(...nums) : 0) + 1).padStart(6, '0')}`;
+  }
+
+  /** Certificate No is system-generated, as in the existing CBS (greyed there). */
+  /** Preview of the certificate number the backend will assign (running number). */
+  private nextCertNo(): string {
+    const nums = (this.holdings ?? []).map((h) => parseInt(h.certNo, 10)).filter((n) => !isNaN(n));
+    return String((nums.length ? Math.max(...nums) : 0) + 1);
   }
 
   private blankPurchaseForm(): BondPurchaseForm {
     const type = this.bondType ?? 'GOVT_SECURITY';
+    this.showMoreDetails = false;
+    this.retrieveCertNo = '';
     return {
       bondType: type,
       dealNo: this.nextDealNo(),
       dealDate: this.asOnDate,
-      dealTime: '',
+      dealTime: new Date().toTimeString().slice(0, 8),
       isin: '',
       scriptCode: '',
-      certNo: '',
+      certNo: this.nextCertNo(),
       settlementType: 'T+0',
       settlementDt: this.asOnDate,
       faceValue: null,
@@ -326,7 +399,7 @@ export class BondInvestmentComponent {
       partyCode: '',
       subType: type === 'GOVT_SECURITY' ? 'SLR' : type === 'NON_SLR' ? 'NON SLR' : 'CORPORATE BOND',
       tbillGlAc: '',
-      crToAc: '310070',
+      crToAc: SETTLEMENT_BANK_GL_OPTIONS[0]?.glCode ?? '',
       premiumAmt: null,
       brokerage: null,
       brokerName: '',
@@ -463,13 +536,41 @@ export class BondInvestmentComponent {
   }
 
   /** Accrued Interest at purchase — interest earned by the seller since the last coupon date. */
+  /** Interest owed to the seller from the last coupon date up to the deal date, on a 30/360 basis —
+   *  interest is counted to the event date, not the date the money moves (Jitendra Sir). */
   get purchaseAccruedInterest(): number {
     const f = this.purchaseForm;
     if (!f.intRate || !f.lastIntDt || !f.dealDate) {
       return 0;
     }
-    const yrs = Math.max(0, yearsBetween(f.lastIntDt, f.dealDate));
-    return Math.round(this.purchaseBaseAmount * (f.intRate / 100) * yrs);
+    return Math.round((this.purchaseBaseAmount * (f.intRate / 100) * days360(f.lastIntDt, f.dealDate)) / 360);
+  }
+
+  get purchaseAccruedDays(): number {
+    const f = this.purchaseForm;
+    return f.lastIntDt && f.dealDate ? days360(f.lastIntDt, f.dealDate) : 0;
+  }
+
+  /** Premium (+) or discount (−) paid over face value. */
+  get purchasePremiumDiscount(): number {
+    const f = this.purchaseForm;
+    if (this.isMutualFund || !f.faceValue || !f.purchaseRate) {
+      return 0;
+    }
+    return Math.round((f.faceValue * (f.purchaseRate - 100)) / 100);
+  }
+
+  /** Re-suggests the last coupon date when the deal date changes. */
+  onDealDateChange(): void {
+    this.suggestLastIntDate();
+  }
+
+  private suggestLastIntDate(): void {
+    const f = this.purchaseForm;
+    const s = this.purchaseScript;
+    if (!this.isMutualFund && s?.maturityDate && f.dealDate) {
+      f.lastIntDt = lastHalfYearlyCouponDate(s.maturityDate, f.dealDate) || f.lastIntDt;
+    }
   }
 
   /** Settlement Amt of Purchase — book value plus accrued interest payable to the seller. */
@@ -504,69 +605,196 @@ export class BondInvestmentComponent {
     });
   }
 
-  /** Fills ISIN + interest rate when a script is picked, mirroring the legacy form's lookup. */
+  get purchaseScript(): (typeof SCRIPT_MASTER)[number] | undefined {
+    return this.scriptOptions.find((x) => x.scriptCode === this.purchaseForm.scriptCode);
+  }
+
+  /** Picking a script pulls its master details into the deal, as the existing CBS does. */
   onScriptChange(): void {
-    const s = this.scriptOptions.find((x) => x.scriptCode === this.purchaseForm.scriptCode);
-    if (s) {
-      this.purchaseForm.isin = s.isin;
+    const s = this.purchaseScript;
+    if (!s) {
+      return;
     }
+    const f = this.purchaseForm;
+    f.isin = s.isin;
+    if (s.couponRate != null) {
+      f.intRate = s.couponRate;
+    }
+    if (s.issueDate) {
+      f.issueDate = s.issueDate;
+    }
+    if (s.maturityDate) {
+      f.redumMatDt = s.maturityDate;
+      const p = periodBetween(s.issueDate, s.maturityDate);
+      f.periodYear = p.years;
+      f.periodMonth = p.months;
+      f.periodDays = p.days;
+    }
+    if (s.slrType) {
+      f.subType = s.slrType === 'NON_SLR' ? 'NON SLR' : 'SLR';
+    }
+    if (this.isMutualFund) {
+      f.productName = s.scriptName;
+    }
+    this.suggestLastIntDate();
+  }
+
+  /** Settlement Date = Deal Date + T+n days (greyed / auto in the existing CBS). */
+  get purchaseSettlementDate(): string {
+    const f = this.purchaseForm;
+    if (!f.dealDate) {
+      return '';
+    }
+    const n = parseInt(f.settlementType.replace('T+', ''), 10) || 0;
+    return addPeriod(f.dealDate, 0, 0, n);
+  }
+
+  /** Parties offered for a new deal — inactive parties are hidden. */
+  get activePartyOptions(): typeof PARTY_MASTER {
+    return this.partyOptions.filter((p) => p.status !== 'INACTIVE');
+  }
+
+  get purchaseInvestmentGlCode(): string {
+    return this.purchaseScript?.glCode || INVESTMENT_GL_BY_TYPE[this.purchaseForm.bondType];
+  }
+
+  glNameOf(glCode: string): string {
+    return INVESTMENT_GL_LOOKUP.find((g) => g.glCode === glCode)?.glName ?? '';
+  }
+
+  /** The journal entry this purchase will post once the checker approves it. */
+  get purchaseAccountingPreview(): AccountingPreviewLine[] {
+    const book = this.purchaseBookValue;
+    const accrued = this.purchaseAccruedInterest;
+    const total = this.purchaseSettlementAmount;
+    const crGl = this.purchaseForm.crToAc;
+    if (!book || !crGl) {
+      return [];
+    }
+    const invGl = this.purchaseInvestmentGlCode;
+    const lines: AccountingPreviewLine[] = [
+      { side: 'Dr', glCode: invGl, glName: this.glNameOf(invGl), amount: book }];
+    if (accrued > 0) {
+      lines.push({
+        side: 'Dr',
+        glCode: INTEREST_RECEIVABLE_GL.glCode,
+        glName: INTEREST_RECEIVABLE_GL.glName,
+        amount: accrued
+      });
+    }
+    lines.push({ side: 'Cr', glCode: crGl, glName: this.glNameOf(crGl), amount: total });
+    return lines;
   }
 
   savePurchase(): void {
     const f = this.purchaseForm;
-    if (!f.certNo || !this.purchaseBaseAmount || !f.partyCode) {
-      this.toast('Please fill Cert No, Face Value / Consider Amt and Party Code.');
+    const missing: string[] = [];
+    if (!f.scriptCode) missing.push('Script Code');
+    if (!f.partyCode) missing.push('Party Code');
+    if (!f.dealDate) missing.push('Deal Date');
+    if (this.isMutualFund) {
+      if (!f.considerAmt) missing.push('Consider Amt');
+      if (!f.nav) missing.push('NAV');
+    } else {
+      if (!f.faceValue) missing.push('Face Value');
+      if (!f.purchaseRate) missing.push('Purchase Rate');
+      if (!f.lastIntDt) missing.push('Last Interest Date');
+    }
+    if (!f.category) missing.push('Category');
+    if (!f.crToAc) missing.push('CR. To A/c');
+    if (missing.length) {
+      this.toast(`Please fill: ${missing.join(', ')}.`);
       return;
     }
-    const holding: InvestmentHolding = {
-      certNo: f.certNo,
-      instrumentType: f.bondType,
-      scriptCode: f.scriptCode || f.isin || f.productName,
-      scriptName: this.isMutualFund
-        ? f.productName
-        : this.scriptOptions.find((s) => s.scriptCode === f.scriptCode)?.scriptName || f.scriptCode || f.isin,
-      party: f.partyCode,
-      subType: f.subType,
-      faceValue: this.purchaseBaseAmount,
-      purchaseRate: this.isMutualFund ? f.nav || 0 : f.purchaseRate || 100,
-      units: this.purchaseUnits,
-      purchaseDate: f.issueDate,
-      maturityDate: this.purchaseMaturityDate || f.issueDate,
-      interestRate: f.intRate || 0,
-      interestFreq: this.isMutualFund ? 'CUMULATIVE' : f.intType,
-      glCode:
-        '31' +
-        (f.bondType === 'GOVT_SECURITY'
-          ? '0020'
-          : f.bondType === 'NON_SLR'
-            ? '0030'
-            : f.bondType === 'BOND'
-              ? '0040'
-              : '0050'),
-      glName: `INVESTMENT IN ${INSTRUMENT_LABELS[f.bondType].toUpperCase()}`,
-      crToAc: f.crToAc,
-      brokerCode: f.brokerName,
-      status: 'ACTIVE'
+    const script = this.purchaseScript;
+    const party = this.partyOptions.find((p) => p.partyCode === f.partyCode);
+    const crGlAccountId = this.glIdByCode.get(f.crToAc);
+    if (!script?.id || !party?.id) {
+      this.toast('Script and Party must be saved in Investment Masters first.');
+      return;
+    }
+    if (!crGlAccountId) {
+      this.toast(`GL ${f.crToAc} was not found in the chart of accounts.`);
+      return;
+    }
+    const body = {
+      bondType: f.bondType,
+      scriptId: script.id,
+      partyId: party.id,
+      dealDate: f.dealDate,
+      dealTime: f.dealTime || '',
+      settlementType: f.settlementType,
+      ...(this.isMutualFund
+        ? { considerAmt: f.considerAmt, nav: f.nav, stampDuty: f.stampDuty ?? null }
+        : { faceValue: f.faceValue, purchaseRate: f.purchaseRate, lastIntDate: f.lastIntDt }),
+      brokerage: f.brokerage ?? null,
+      category: f.category,
+      crGlAccountId,
+      subType: f.subType || '',
+      otherDetails: this.purchaseOtherDetails(),
+      dateFormat: 'dd-MM-yyyy',
+      locale: 'en'
     };
-    this.holdings = [
-      holding,
-      ...this.holdings
-    ];
-    this.txns = [
-      {
-        certNo: holding.certNo,
-        instrumentType: f.bondType,
-        txnType: 'PURCHASE',
-        voucherNo: `INV/PUR/${f.dealNo}`,
-        txnDate: f.dealDate,
-        amount: this.purchaseSettlementAmount,
-        particulars: `Purchase Deal ${f.dealNo} - ${holding.scriptName} - ${holding.party}${f.category ? ' [' + f.category + ']' : ''}`
+    this.investmentService.createPurchase(body).subscribe({
+      next: (res) => {
+        this.toast(`Deal ${res.resourceIdentifier} saved. GL posting will follow once accounting is approved.`);
+        this.activeTab = 'holdings';
+        this.loadPurchases();
       },
-      ...this.txns
-    ];
-    this.toast(`${INSTRUMENT_LABELS[f.bondType]} Certificate ${holding.certNo} saved successfully.`);
-    this.purchaseForm = this.blankPurchaseForm();
-    this.activeTab = 'holdings';
+      error: (err) => this.toast(apiErrorMessage(err))
+    });
+  }
+
+  /** The optional "More Details" fields, kept with the deal as they were entered. */
+  private purchaseOtherDetails(): Record<string, string | number> {
+    const f = this.purchaseForm;
+    const fields: Record<string, string | number | null> = {
+      tradeNo: f.tradeNo,
+      orderNo: f.orderNo,
+      brokerCode: f.brokerName,
+      recommAuthority: f.recommAuthority,
+      sanctionAuthority: f.sanctionAuthority,
+      meetDate: f.meetDt,
+      resoNo: f.resoNo,
+      dealType: f.dealType,
+      market: f.market,
+      markCblo: f.markCblo,
+      paymentMode: f.paymentMode,
+      deliveryMode: f.deliveryMode,
+      lien: f.lien,
+      lienAmount: f.lienAmount,
+      lienReason: f.lienReason,
+      bondRating: f.bondRating,
+      corpBond: f.corpBond,
+      sglWithBank: f.sglWithBank,
+      tbillGlAc: f.tbillGlAc,
+      intType: f.intType,
+      intDate: f.intDate,
+      folioNo: f.folioNo,
+      callOption: f.callOption,
+      descInv: f.descInv,
+      fromDist: f.fromDist,
+      toDist: f.toDist,
+      amortizeAmt: f.amortizeAmt,
+      registerAddress: f.registerAdd,
+      registerCity: f.regiCity,
+      registerPin: f.regiPin,
+      remarks: f.remarks,
+      description: f.description,
+      tradeAmt: f.tradeAmt,
+      holdingDays: f.holdingDays,
+      stampDutyAc: f.stampDutyAc
+    };
+    const out: Record<string, string | number> = {};
+    for (const [
+      k,
+      v
+    ] of Object.entries(fields)) {
+      if (v !== null && v !== undefined && v !== '') {
+        out[k] = v;
+      }
+    }
+    return out;
   }
 
   cancelPurchase(): void {
@@ -576,9 +804,10 @@ export class BondInvestmentComponent {
 
   /** Legacy "Retrieve" button — loads an existing deal back into the form by Cert No. */
   retrievePurchase(): void {
-    const h = this.holdings.find((x) => x.certNo === this.purchaseForm.certNo.trim());
+    const certNo = this.retrieveCertNo.trim();
+    const h = this.holdings.find((x) => x.certNo === certNo);
     if (!h) {
-      this.toast(`Cert No ${this.purchaseForm.certNo} not found.`);
+      this.toast(`Cert No ${certNo || '(blank)'} not found.`);
       return;
     }
     this.purchaseForm = {
@@ -587,7 +816,8 @@ export class BondInvestmentComponent {
       certNo: h.certNo,
       scriptCode: h.scriptCode,
       isin: this.scriptOptions.find((s) => s.scriptCode === h.scriptCode)?.isin || '',
-      partyCode: h.party,
+      dealNo: h.dealNo ?? '',
+      partyCode: h.partyCode ?? '',
       subType: h.subType,
       faceValue: h.faceValue,
       considerAmt: h.faceValue,
@@ -599,22 +829,26 @@ export class BondInvestmentComponent {
       intType: h.interestFreq,
       brokerName: h.brokerCode,
       crToAc: h.crToAc,
-      productName: h.scriptName
+      productName: h.scriptName,
+      category: h.category ?? ''
     };
     this.bondType = h.instrumentType as BondType;
     this.toast(`Deal for Cert No ${h.certNo} retrieved.`);
   }
 
   dropPurchase(): void {
-    const certNo = this.purchaseForm.certNo;
-    if (!this.holdings.some((h) => h.certNo === certNo)) {
-      this.toast('Nothing to drop — this deal is not yet saved.');
+    const h = this.holdings.find((x) => x.certNo === this.purchaseForm.certNo);
+    if (!h?.id) {
+      this.toast('Retrieve a saved deal first, then Drop.');
       return;
     }
-    this.holdings = this.holdings.filter((h) => h.certNo !== certNo);
-    this.txns = this.txns.filter((t) => t.certNo !== certNo);
-    this.purchaseForm = this.blankPurchaseForm();
-    this.toast(`Cert No ${certNo} dropped.`);
+    this.investmentService.deletePurchase(h.id).subscribe({
+      next: () => {
+        this.toast(`Deal ${h.dealNo} (Cert No ${h.certNo}) dropped.`);
+        this.loadPurchases();
+      },
+      error: (err) => this.toast(apiErrorMessage(err))
+    });
   }
 
   exitPurchase(): void {