┌─────────────────────────────────────────────────────────────────────────────┐
│                     ODOO EMAIL TEMPLATE ARCHITECTURE                          │
├─────────────────────────────────────────────────────────────────────────────┤
│                                                                               │
│  mail.template                                                               │
│  ├── Inherits: mail.render.mixin (rendering engine)                          │
│  ├── Inherits: template.reset.mixin (reset - Odoo 16+)                       │
│  │                                                                           │
│  ├── Header Fields (inline_template engine):                                 │
│  │   • subject        • email_from       • email_to                          │
│  │   • email_cc       • reply_to         • partner_to                        │
│  │                                                                           │
│  ├── Content Fields (QWeb engine):                                           │
│  │   • body_html                                                             │
│  │                                                                           │
│  ├── Attachment Fields:                                                      │
│  │   • attachment_ids (static)                                               │
│  │   • report_template (Odoo 14-16) / report_template_ids (Odoo 17+)        │
│  │   • report_name (dynamic filename)                                        │
│  │                                                                           │
│  └── Configuration:                                                          │
│      • email_layout_xmlid   • auto_delete    • mail_server_id               │
│      • use_default_to       • scheduled_date                                 │
│                                                                               │
└─────────────────────────────────────────────────────────────────────────────┘

mail.template.send_mail_batch(res_ids)
    │
    ├─► _generate_template(res_ids, render_fields)
    │       │
    │       ├─► _classify_per_lang()        # Group by language
    │       │
    │       ├─► _render_field() for each:
    │       │       • subject (inline_template)
    │       │       • body_html (qweb)
    │       │       • email_from, email_to, etc.
    │       │
    │       ├─► _generate_template_recipients()
    │       │
    │       ├─► _generate_template_attachments()
    │       │       • Static attachments
    │       │       • Report PDF generation
    │       │
    │       └─► Return rendered values dict
    │
    ├─► Create mail.mail records
    │
    ├─► Apply email_layout_xmlid (if set)
    │       └─► ir.qweb._render(layout_xmlid, context)
    │
    └─► Send via mail_server_id or default

undefined

undefined

<!-- Escaped output (safe) -->
<t t-out="object.name"/>
<t t-out="object.partner_id.name or 'Unknown'"/>

<!-- Format with helper -->
<t t-out="format_amount(object.amount_total, object.currency_id)"/>
<t t-out="format_date(object.date_order)"/>
<t t-out="format_datetime(object.create_date, tz='UTC', dt_format='long')"/>

<t t-if="object.state == 'draft'">
    This is a draft.
</t>
<t t-elif="object.state == 'sent'">
    This has been sent.
</t>
<t t-else="">
    This is confirmed.
</t>

<t t-foreach="object.order_line" t-as="line">
    <tr>
        <td t-out="line.name"/>
        <td t-out="line.product_uom_qty"/>
        <td t-out="format_amount(line.price_subtotal, object.currency_id)"/>
    </tr>
</t>

<!-- Dynamic attribute -->
<a t-att-href="object.get_portal_url()">View</a>

<!-- Formatted attribute (with interpolation) -->
<a t-attf-href="/web/image/product.product/{{ line.product_id.id }}/image_128">
    <img t-attf-src="/web/image/product.product/{{ line.product_id.id }}/image_128"/>
</a>

{
    # Message Information
    'message': mail.message,           # Message object with body, record_name
    'subtype': mail.message.subtype,   # Message subtype

    # Display Control
    'has_button_access': Boolean,      # Show action button
    'button_access': {                 # CTA button config
        'url': String,
        'title': String
    },
    'subtitles': List[String],         # Header subtitles

    # Record Information
    'record': record,                  # The document
    'record_name': String,             # Display name
    'model_description': String,       # Human-readable model

    # Tracking
    'tracking_values': [               # Field changes
        (field_name, old_value, new_value),
    ],

    # Signature
    'email_add_signature': Boolean,    # Include signature
    'signature': HTML,                 # User signature

    # Company
    'company': res.company,            # Company object
    'website_url': String,             # Base URL

    # Branding (Odoo 19+)
    'company.email_primary_color': String,    # Button text color
    'company.email_secondary_color': String,  # Button background

    # Utilities
    'is_html_empty': Function,         # Check empty HTML
}

<?xml version="1.0" encoding="UTF-8"?>
<odoo>
    <data noupdate="1">
        <record id="email_template_basic_notification" model="mail.template">
            <field name="name">Basic Notification</field>
            <field name="model_id" ref="model_your_model"/>
            <field name="subject">{{ object.name }} - Notification</field>
            <field name="email_from">{{ (object.company_id.email or user.email_formatted) }}</field>
            <field name="email_to">{{ object.partner_id.email }}</field>
            <field name="email_layout_xmlid">mail.mail_notification_layout</field>
            <field name="body_html" type="html">
<div>
    <p>Dear <t t-out="object.partner_id.name"/>,</p>
    <p>This is a notification regarding <strong t-out="object.name"/>.</p>
    <t t-if="object.description">
        <p t-out="object.description"/>
    </t>
    <p>Best regards,<br/><t t-out="object.company_id.name"/></p>
</div>
            </field>
            <field name="auto_delete" eval="True"/>
        </record>
    </data>
</odoo>

<?xml version="1.0" encoding="UTF-8"?>
<odoo>
    <data noupdate="1">
        <record id="email_template_document" model="mail.template">
            <field name="name">Send Document</field>
            <field name="model_id" ref="model_your_model"/>
            <field name="subject">
                {{ object.state in ('draft', 'sent') and 'Quotation' or 'Order' }} {{ object.name }}
            </field>
            <field name="email_from">{{ (object.user_id.email_formatted or user.email_formatted) }}</field>
            <field name="partner_to">{{ object.partner_id.id }}</field>
            <!-- Odoo 17+ use report_template_ids -->
            <field name="report_template_ids" eval="[(4, ref('module.report_action_id'))]"/>
            <field name="report_name">{{ (object.name or 'Document').replace('/', '-') }}</field>
            <field name="email_layout_xmlid">mail.mail_notification_layout</field>
            <field name="body_html" type="html">
<div>
    <t t-set="doc_name" t-value="'quotation' if object.state in ('draft', 'sent') else 'order'"/>
    <p>Dear <t t-out="object.partner_id.name"/>,</p>
    <p>Please find attached your <t t-out="doc_name"/>
       <strong t-out="object.name"/> amounting to
       <strong t-out="format_amount(object.amount_total, object.currency_id)"/>.</p>
    <p>Do not hesitate to contact us if you have any questions.</p>
</div>
            </field>
        </record>
    </data>
</odoo>

<table border="0" cellpadding="0" cellspacing="0" width="100%"
       style="border-collapse: collapse;">
    <thead>
        <tr style="background-color: #875A7B; color: white;">
            <th style="padding: 8px;">Product</th>
            <th style="padding: 8px;">Quantity</th>
            <th style="padding: 8px; text-align: right;">Price</th>
        </tr>
    </thead>
    <tbody>
        <t t-foreach="object.order_line" t-as="line">
            <t t-if="line.display_type == 'line_section'">
                <tr>
                    <td colspan="3" style="font-weight: bold; padding: 8px; background-color: #f5f5f5;">
                        <t t-out="line.name"/>
                    </td>
                </tr>
            </t>
            <t t-elif="line.display_type == 'line_note'">
                <tr>
                    <td colspan="3" style="font-style: italic; padding: 8px;">
                        <t t-out="line.name"/>
                    </td>
                </tr>
            </t>
            <t t-else="">
                <tr t-att-style="'background-color: #f9f9f9' if line_index % 2 == 0 else ''">
                    <td style="padding: 8px;">
                        <t t-out="line.product_id.name"/>
                    </td>
                    <td style="padding: 8px; text-align: center;">
                        <t t-out="line.product_uom_qty"/>
                        <t t-out="line.product_uom.name"/>
                    </td>
                    <td style="padding: 8px; text-align: right;">
                        <t t-out="format_amount(line.price_subtotal, object.currency_id)"/>
                    </td>
                </tr>
            </t>
        </t>
    </tbody>
    <tfoot>
        <tr style="font-weight: bold; background-color: #f5f5f5;">
            <td colspan="2" style="padding: 8px; text-align: right;">Total:</td>
            <td style="padding: 8px; text-align: right;">
                <t t-out="format_amount(object.amount_total, object.currency_id)"/>
            </td>
        </tr>
    </tfoot>
</table>

<t t-set="button_color" t-value="company.email_secondary_color or '#875A7B'"/>
<table border="0" cellpadding="0" cellspacing="0" width="100%">
    <tr>
        <td align="center" style="padding: 16px;">
            <a t-att-href="object.get_portal_url()"
               t-att-style="'display: inline-block; padding: 10px 20px; color: #ffffff; text-decoration: none; border-radius: 3px; background-color: %s' % button_color">
                View Online
            </a>
        </td>
    </tr>
</table>

<t t-if="object.state == 'draft'">
    <p style="color: #856404; background-color: #fff3cd; padding: 10px; border-radius: 4px;">
        <strong>Draft:</strong> This document is not yet confirmed.
    </p>
</t>
<t t-elif="object.state == 'sent'">
    <p style="color: #0c5460; background-color: #d1ecf1; padding: 10px; border-radius: 4px;">
        <strong>Awaiting Confirmation:</strong> Please review and confirm.
    </p>
</t>
<t t-elif="object.state == 'done'">
    <p style="color: #155724; background-color: #d4edda; padding: 10px; border-radius: 4px;">
        <strong>Completed:</strong> This document has been processed.
    </p>
</t>

<t t-if="object.payment_state not in ('paid', 'in_payment')">
    <div style="background-color: #f8f9fa; padding: 15px; margin: 15px 0; border-radius: 4px;">
        <h4 style="margin: 0 0 10px 0;">Payment Information</h4>
        <t t-if="object.payment_reference">
            <p><strong>Reference:</strong> <t t-out="object.payment_reference"/></p>
        </t>
        <t t-if="object.partner_bank_id">
            <p><strong>Bank Account:</strong> <t t-out="object.partner_bank_id.acc_number"/></p>
            <t t-if="object.partner_bank_id.bank_id">
                <p><strong>Bank:</strong> <t t-out="object.partner_bank_id.bank_id.name"/></p>
            </t>
        </t>
        <t t-if="object.amount_residual">
            <p><strong>Amount Due:</strong>
               <t t-out="format_amount(object.amount_residual, object.currency_id)"/>
            </p>
        </t>
    </div>
</t>

<?xml version="1.0" encoding="UTF-8"?>
<odoo>
    <!-- Report Action -->
    <record id="action_report_document" model="ir.actions.report">
        <field name="name">Document Report</field>
        <field name="model">your.model</field>
        <field name="report_type">qweb-pdf</field>
        <field name="report_name">module_name.report_document_template</field>
        <field name="report_file">module_name.report_document_template</field>
        <field name="print_report_name">'Document - %s' % object.name</field>
        <field name="binding_model_id" ref="model_your_model"/>
        <field name="binding_type">report</field>
    </record>

    <!-- Report Template -->
    <template id="report_document_template">
        <t t-call="web.html_container">
            <t t-foreach="docs" t-as="doc">
                <t t-call="web.external_layout">
                    <div class="page">
                        <h2><t t-out="doc.name"/></h2>

                        <div class="row">
                            <div class="col-6">
                                <strong>Date:</strong>
                                <span t-field="doc.date"/>
                            </div>
                            <div class="col-6 text-end">
                                <strong>Reference:</strong>
                                <span t-out="doc.reference"/>
                            </div>
                        </div>

                        <!-- Content goes here -->

                    </div>
                </t>
            </t>
        </t>
    </template>
</odoo>

<table class="table table-sm o_main_table">
    <thead>
        <tr>
            <th class="text-start">Description</th>
            <th class="text-center">Quantity</th>
            <th class="text-end">Unit Price</th>
            <th class="text-end">Amount</th>
        </tr>
    </thead>
    <tbody>
        <t t-foreach="doc.line_ids" t-as="line">
            <tr>
                <td><span t-field="line.name"/></td>
                <td class="text-center"><span t-field="line.quantity"/></td>
                <td class="text-end"><span t-field="line.price_unit"/></td>
                <td class="text-end"><span t-field="line.price_subtotal"/></td>
            </tr>
        </t>
    </tbody>
</table>

<!-- Totals -->
<div class="row justify-content-end">
    <div class="col-4">
        <table class="table table-sm">
            <tr>
                <td><strong>Subtotal</strong></td>
                <td class="text-end"><span t-field="doc.amount_untaxed"/></td>
            </tr>
            <tr>
                <td>Taxes</td>
                <td class="text-end"><span t-field="doc.amount_tax"/></td>
            </tr>
            <tr class="border-top">
                <td><strong>Total</strong></td>
                <td class="text-end"><span t-field="doc.amount_total"/></td>
            </tr>
        </table>
    </div>
</div>

<!-- Force page break before element -->
<div style="page-break-before: always;">
    <h3>New Page Content</h3>
</div>

<!-- Prevent page break inside element -->
<div style="page-break-inside: avoid;">
    <table><!-- Table that should stay together --></table>
</div>

<!-- Force page break after element -->
<div style="page-break-after: always;">
    <p>End of section</p>
</div>

┌─────────────────────────────────────────────────────────────────┐
│                 TEMPLATE VALIDATION CHECKLIST                     │
├─────────────────────────────────────────────────────────────────┤
│                                                                   │
│  1. MODEL VALIDATION                                             │
│     □ Model exists in target Odoo version                        │
│     □ Model has required fields (partner_id, etc.)               │
│     □ Model inherits mail.thread (if notification)               │
│                                                                   │
│  2. FIELD VALIDATION                                             │
│     □ All {{ object.field }} references exist                    │
│     □ All t-out="object.field" references exist                  │
│     □ Related fields are valid (object.partner_id.name)          │
│                                                                   │
│  3. SYNTAX VALIDATION                                            │
│     □ QWeb tags properly closed                                  │
│     □ Jinja2 expressions balanced {{ }}                          │
│     □ No mixing of t-esc (Odoo 14) and t-out (Odoo 15+)         │
│                                                                   │
│  4. VERSION COMPATIBILITY                                        │
│     □ report_template vs report_template_ids (Odoo 17+)          │
│     □ template_category (Odoo 16+)                               │
│     □ Company branding colors (Odoo 19+)                         │
│                                                                   │
│  5. SECURITY VALIDATION                                          │
│     □ No unsafe eval() or exec()                                 │
│     □ No arbitrary file access                                   │
│     □ Sandbox-safe expressions                                   │
│                                                                   │
└─────────────────────────────────────────────────────────────────┘

undefined

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