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docs/README.md

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+# Data Entry
+
+The Data Entry app is where you manually enter aggregated data in DHIS2. You
+register data for an organisation unit, a period, and a set of data elements
+(data set) at a time. A data set often corresponds to a paper-based data
+collection tool. You configure the data sets in the Maintenance app.
+
+**Note:**
+
+If a data set has both a section form and a custom form, the system displays
+the custom form during data entry. Users who enter data can't select which form
+they want to use. In web-based data entry the order of display preference is:
+
+1. Custom form (if it exists)
+1. Section form (if it exists)
+1. Default form
+
+<!-- @TODO: We don't support mobile browser currently, is this something we
+need to support for feature parity? -->
+Mobile devices do not support custom forms. In mobile-based data entry the
+order of display preference is:
+
+1. Section form (if it exists)
+1. Default form
+
+## Selecting a form
+
+In order to select a form, the following three values are mandatory:
+
+1. Data set
+1. Period
+1. Organisation unit
+
+![Form context selection without attribut option combination](./assets/context_selection_without_aoc.png)
+
+A data set, that has not been linked with an explicitly set attribute option
+combination, will be linked to the "default" category which has only one
+option: "Default option", therefore the user does not have to select any
+category option.
+
+### Data-set-dependent, required, categories
+
+Depending on the data set, another selector item will be displayed, which will
+render a set of required category inputs once opened.
+
+![Form context selection with attribut option combination](./assets/context_selection_with_aoc.png)
+
+### Section filter
+
+When a data set is not connected to a custom form and is not a tabbed form, the
+displayed section can be filtered by selecting a specific section in the
+"Section" selection item.
+
+![Form context selection with attribut option combination](./assets/context_selection_section_filter.png)
+
+## Editing forms in an auto-generated form
+
+When successfully selecting a form and the selected data set is not connected
+to a custom form, the app will render an auto-generated form, based on the data
+set (and the category options - if applicable).
+
+### Keyboard controls
+
+The Data Entry app supports a limited amount of keyboard controls for easier
+handling of the form:
+
+| Description | Keyboard command | Exception |
+|-|-|-|
+| Go to the next input field | `Enter` or `Tab` | `Enter` has to be implemented in custom forms; `Tab` is the default browser behavior; should work in custom forms as well |
+| Go to the previous input field | `Shift + Tab` | Default browser behavior; should work in custom forms as well |
+| Open the details section of a data value | `Shift + Enter` |
+
+### Filtering fields
+
+The app renders an input field above the forms which can be used to search for
+particular input fields (except custom forms):
+
+![Form filtering](./assets/form_filtering.png)
+
+### Tabbed forms
+
+Data sets have an option to be rendered as tabs (see Maintenance app
+documentation).
+
+![Maintenance app - Render sections as tabs](./assets/maintenance_app_render_sections_as_tabs.png)
+
+When the option is set, the form will be rendered in tabs
+instead of in sections displayed underneath each other:
+
+![Tabbed form](./assets/tabbed_form.png)
+
+### Viewing the data value details
+
+There are several ways to access the details of a data value:
+
+- By doubling click on the input field
+- By pressing Shift + Enter when focussing on an input field
+- By clicking on the "View details" control in the bottom bar
+
+Data details are information and actions about a specific data item in a data
+set. The data details are split into the following units:
+
+* Basic information
+* Comment.
+* Customisable value limits.
+* Historical values reference.
+* Audit log.
+
+The individual units are collapsed by default, only the first one with the
+basic information will be expanded initially.
+
+Units can be expanded/collapsed by clicking on the header (which is the title
+and the chevron icon).
+
+#### Viewing the basic information of a data value
+
+The first unit in the data value details contains the following values:
+
+* name
+* code
+* ID
+* last updated date
+* follow-up state
+
+##### Marking data values for follow-up
+
+This unit contains a button which can be used to mark a data value for
+follow-up or unmark it if it has been marked in the past.
+
+#### Editing the comment of a data value
+
+The second unit contains the comment. By default the comment can't be edited.
+
+![@TODO: Screenshot of comment text & button]()
+
+There is a button which can be used to change the comment into an input
+field with the current comment as initial value.
+
+![@TODO: Screenshot of comment text area]()
+
+The changes made can be saved by clicking on the "Save comment" button.
+Alternatively the cancel button can be clicked, which will discard the changes
+and revert to the comment before making any changes.
+
+#### Adding/Editing the minimum and maximum range of a data value
+
+In order to edit these values, the data value details section for the
+respective data value has to be opened first. Then open the "Min- and max
+range" section in the details section.
+
+If the data value does not have any values attached, a button will be displayed
+that will cause two input fields to show up:
+
+![No limits set](./assets/limits_no_limits.png)
+
+If the data value does have some values attached already, these values will be
+rendered. In order to edit the values, the "Edit limits" button has to be
+pressed, which will cause the inputs to show up as well:
+
+![Limits already exist](./assets/limits_exist_already.png)
+
+When adding or editing the limits, the updated values can either be saved by
+clicking on the "Save limits" button or discarded by clicking on the "Cancel"
+button:
+
+![Limits already exist](./assets/limits_editing_limits.png)
+
+Limits can be deleted by clicking on the "Delete limits button" both in normal
+and in edit mode:
+
+![Limits already exist](./assets/limits_exist_already.png)
+
+#### Viewing historical values in a chart
+
+
+## Editing forms in a custom form
+
+
+## Data values
+
+
+### Marking data values for follow-up
+
+
+### Add/Edit min- and max-range of the value
+
+
+## Offline support
+
+
+### Editing approved forms
+
+
+## Related resources
+