Deepen all business modules: methods, validations, workflows

Account:
- action_post: partner validation, line count check, sequence number
  assignment (JOURNAL/YYYY/NNNN format)
- action_register_payment: opens payment wizard from invoice
- remove_move_reconcile: undo reconciliation, reset residuals
- Register Payment button in invoice form (visible when posted+unpaid)

Sale:
- action_cancel: cancels linked draft invoices + SO state
- action_draft: reset cancelled SO to draft
- action_view_invoice: navigate to linked invoices
- Cancel/Reset buttons in form view header

Purchase:
- button_draft: reset cancelled PO to draft
- action_create_bill already existed

Stock:
- action_cancel on picking: cancels moves + picking state

CRM:
- action_set_won_rainbowman: sets Won stage + rainbow effect
- convert_opportunity: lead→opportunity type switch

HR:
- hr.contract model (name, employee, wage, dates, state)

Project:
- action_blocked on task (kanban_state)
- Task stage seed data (New, In Progress, Done, Cancelled)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

addons/account/models/account_move.go

@@ -205,6 +205,25 @@ func initAccountMove() {
 			if state != "draft" {
 				return nil, fmt.Errorf("account: can only post draft entries (current: %s)", state)
 			}
+
+			// Check partner is set for invoice types
+			var moveType string
+			env.Tx().QueryRow(env.Ctx(), `SELECT move_type FROM account_move WHERE id = $1`, id).Scan(&moveType)
+			if moveType != "entry" {
+				var partnerID *int64
+				env.Tx().QueryRow(env.Ctx(), `SELECT partner_id FROM account_move WHERE id = $1`, id).Scan(&partnerID)
+				if partnerID == nil || *partnerID == 0 {
+					return nil, fmt.Errorf("account: invoice requires a partner")
+				}
+			}
+
+			// Check at least one line exists
+			var lineCount int
+			env.Tx().QueryRow(env.Ctx(), `SELECT count(*) FROM account_move_line WHERE move_id = $1`, id).Scan(&lineCount)
+			if lineCount == 0 {
+				return nil, fmt.Errorf("account: cannot post an entry with no lines")
+			}
+
 			// Check balanced
 			var debitSum, creditSum float64
 			env.Tx().QueryRow(env.Ctx(),
@@ -214,6 +233,34 @@ func initAccountMove() {
 			if diff < -0.005 || diff > 0.005 {
 				return nil, fmt.Errorf("account: cannot post unbalanced entry (debit=%.2f, credit=%.2f)", debitSum, creditSum)
 			}
+
+			// Assign sequence number if name is still "/"
+			var name string
+			env.Tx().QueryRow(env.Ctx(), `SELECT name FROM account_move WHERE id = $1`, id).Scan(&name)
+			if name == "/" || name == "" {
+				// Generate sequence number
+				var journalID int64
+				var journalCode string
+				env.Tx().QueryRow(env.Ctx(),
+					`SELECT j.id, j.code FROM account_journal j
+					 JOIN account_move m ON m.journal_id = j.id WHERE m.id = $1`, id,
+				).Scan(&journalID, &journalCode)
+
+				// Get next sequence number
+				var nextNum int64
+				env.Tx().QueryRow(env.Ctx(),
+					`SELECT COALESCE(MAX(sequence_number), 0) + 1 FROM account_move WHERE journal_id = $1`,
+					journalID).Scan(&nextNum)
+
+				// Format: journalCode/YYYY/NNNN
+				year := time.Now().Format("2006")
+				newName := fmt.Sprintf("%s/%s/%04d", journalCode, year, nextNum)
+
+				env.Tx().Exec(env.Ctx(),
+					`UPDATE account_move SET name = $1, sequence_number = $2 WHERE id = $3`,
+					newName, nextNum, id)
+			}
+
 			if _, err := env.Tx().Exec(env.Ctx(),
 				`UPDATE account_move SET state = 'posted' WHERE id = $1`, id); err != nil {
 				return nil, err
@@ -255,6 +302,23 @@ func initAccountMove() {
 		return true, nil
 	})
 
+	// action_register_payment: opens the payment register wizard.
+	// Mirrors: odoo/addons/account/models/account_move.py action_register_payment()
+	m.RegisterMethod("action_register_payment", func(rs *orm.Recordset, args ...interface{}) (interface{}, error) {
+		return map[string]interface{}{
+			"type":      "ir.actions.act_window",
+			"name":      "Register Payment",
+			"res_model": "account.payment.register",
+			"view_mode": "form",
+			"views":     [][]interface{}{{nil, "form"}},
+			"target":    "new",
+			"context": map[string]interface{}{
+				"active_model": "account.move",
+				"active_ids":   rs.IDs(),
+			},
+		}, nil
+	})
+
 	// -- Business Method: create_invoice_with_tax --
 	// Creates a customer invoice with automatic tax line generation.
 	// For each product line that carries a tax_id, a separate tax line
@@ -929,6 +993,32 @@ func initAccountMoveLine() {
 
 		return true, nil
 	})
+
+	// remove_move_reconcile: undo reconciliation on selected lines.
+	// Mirrors: odoo/addons/account/models/account_move_line.py remove_move_reconcile()
+	m.RegisterMethod("remove_move_reconcile", func(rs *orm.Recordset, args ...interface{}) (interface{}, error) {
+		env := rs.Env()
+		for _, lineID := range rs.IDs() {
+			// Find partial reconciles involving this line
+			env.Tx().Exec(env.Ctx(),
+				`DELETE FROM account_partial_reconcile WHERE debit_move_id = $1 OR credit_move_id = $1`, lineID)
+			// Reset residual to balance
+			env.Tx().Exec(env.Ctx(),
+				`UPDATE account_move_line SET amount_residual = balance, full_reconcile_id = NULL WHERE id = $1`, lineID)
+		}
+		// Clean up orphaned full reconciles
+		env.Tx().Exec(env.Ctx(),
+			`DELETE FROM account_full_reconcile WHERE id NOT IN (SELECT DISTINCT full_reconcile_id FROM account_partial_reconcile WHERE full_reconcile_id IS NOT NULL)`)
+		// Update payment states
+		for _, lineID := range rs.IDs() {
+			var moveID int64
+			env.Tx().QueryRow(env.Ctx(), `SELECT move_id FROM account_move_line WHERE id = $1`, lineID).Scan(&moveID)
+			if moveID > 0 {
+				updatePaymentState(env, moveID)
+			}
+		}
+		return true, nil
+	})
 }
 
 // initAccountPayment registers account.payment.