working on invoice form

18 files changed, 738 insertions, 41 deletions

diff --git a/docs/README.rst b/docs/README.rst
index 7dedc8d..4affde6 100644
--- a/docs/README.rst
+++ b/docs/README.rst
@@ -36,5 +36,6 @@ This section lists all country specific implementations to be compliant. If the
 
 3. Dependencies
 ---------------
-- ImGui 1.92.1
-- simclist 1.5
\ No newline at end of file
+- ImGui 1.92.1 (https://github.com/ocornut/imgui)
+- simclist 1.5 (https://mij.oltrelinux.com/devel/simclist/)
+- ImGuiDatePicker (https://github.com/DnA-IntRicate/ImGuiDatePicker)
\ No newline at end of file
diff --git a/include/administration.hpp b/include/administration.hpp
index 68deb78..0917ee5 100644
--- a/include/administration.hpp
+++ b/include/administration.hpp
@@ -95,8 +95,8 @@ typedef struct
     char customer_id[16];
     char supplier_id[16];
     time_t issued_at;
-    time_t delivered_at;
     time_t expires_at;
+    time_t delivered_at;
     char document[255];
     list_t billing_items;
     char project_id[16];
@@ -147,6 +147,7 @@ u32     administration_get_contact_count();
 u32     administration_get_contacts(u32 page_index, u32 page_size, contact* buffer);
 contact administration_create_empty_contact();
 bool    administration_is_contact_valid(contact data);
+int     administration_get_contact_recommendations(contact* buffer, int buf_size, char* name);
 
 void    administration_cancel_project(project data);
 bool    administration_remove_project(project data);
@@ -155,6 +156,7 @@ bool    administration_update_project(project data);
 char*   administration_project_get_status_string(project data);
 u32     administration_get_project_count();
 u32     administration_get_projects(u32 page_index, u32 page_size, project* buffer);
+bool    administration_is_project_valid(project data);
 project administration_create_empty_project();
 
 u32     administration_get_tax_bracket_count();
diff --git a/include/strops.hpp b/include/strops.hpp
index daa1d71..08dbd5a 100644
--- a/include/strops.hpp
+++ b/include/strops.hpp
@@ -1,3 +1,4 @@
 #pragma once
 
-size_t strops_copy(char *dst, const char *src, size_t size);
\ No newline at end of file
+size_t strops_copy(char *dst, const char *src, size_t size);
+char* strops_stristr(char* a, char* b);
\ No newline at end of file
diff --git a/include/ui.hpp b/include/ui.hpp
index 7a02329..5c5b6fc 100644
--- a/include/ui.hpp
+++ b/include/ui.hpp
@@ -11,7 +11,7 @@ typedef enum
 void ui_helper_draw_required_tag();
 void ui_helper_show_toast(const char* msg);
 void ui_helper_draw_toasts();
-void ui_helper_TextInputWithAutocomplete(const char* label, const char* hint, char* buffer, size_t buf_size, char** suggestions, int suggestion_count);
+int ui_helper_TextInputWithAutocomplete(const char* label, const char* hint, char* buffer, size_t buf_size, char** suggestions, int suggestion_count);
 
 void ui_draw_main();
 void ui_draw_contacts();
diff --git a/libs/ImGuiDatePicker/ImGuiDatePicker.cpp b/libs/ImGuiDatePicker/ImGuiDatePicker.cpp
new file mode 100644
index 0000000..8c81b2b
--- /dev/null
+++ b/libs/ImGuiDatePicker/ImGuiDatePicker.cpp
@@ -0,0 +1,393 @@
+#include "ImGuiDatePicker.hpp"
+#include <imgui_internal.h>
+#include <cstdint>
+#include <chrono>
+#include <vector>
+#include <unordered_map>
+
+
+#define GET_DAY(timePoint) int(timePoint.tm_mday)
+#define GET_MONTH_UNSCALED(timePoint) timePoint.tm_mon
+#define GET_MONTH(timePoint) int(GET_MONTH_UNSCALED(timePoint) + 1)
+#define GET_YEAR(timePoint) int(timePoint.tm_year + 1900)
+
+#define SET_DAY(timePoint, day) timePoint.tm_mday = day
+#define SET_MONTH(timePoint, month) timePoint.tm_mon = month - 1
+#define SET_YEAR(timePoint, year) timePoint.tm_year = year - 1900
+
+namespace ImGui
+{
+    static const std::vector<std::string> MONTHS =
+    {
+        "January",
+        "February",
+        "March",
+        "April",
+        "May",
+        "June",
+        "July",
+        "August",
+        "September",
+        "October",
+        "November",
+        "December"
+    };
+
+    static const std::vector<std::string> DAYS =
+    {
+        "Mo",
+        "Tu",
+        "We",
+        "Th",
+        "Fr",
+        "Sa",
+        "Su"
+    };
+
+    // Implements Zeller's Congruence to determine the day of week [1, 7](Mon-Sun) from the given parameters
+    inline static int DayOfWeek(int dayOfMonth, int month, int year) noexcept
+    {
+        if ((month == 1) || (month == 2))
+        {
+            month += 12;
+            year -= 1;
+        }
+
+        int h = (dayOfMonth
+            + static_cast<int>(std::floor((13 * (month + 1)) / 5.0))
+            + year
+            + static_cast<int>(std::floor(year / 4.0))
+            - static_cast<int>(std::floor(year / 100.0))
+            + static_cast<int>(std::floor(year / 400.0))) % 7;
+
+        return static_cast<int>(std::floor(((h + 5) % 7) + 1));
+    }
+
+    constexpr static bool IsLeapYear(int year) noexcept
+    {
+        if ((year % 400) == 0)
+            return true;
+
+        if ((year % 4 == 0) && ((year % 100) != 0))
+            return true;
+
+        return false;
+    }
+
+    inline static int NumDaysInMonth(int month, int year)
+    {
+        if (month == 2)
+            return IsLeapYear(year) ? 29 : 28;
+
+        // Month index paired to the number of days in that month excluding February
+        static const std::unordered_map<int, int> monthDayMap =
+        {
+            { 1,  31 },
+            { 3,  31 },
+            { 4,  30 },
+            { 5,  31 },
+            { 6,  30 },
+            { 7,  31 },
+            { 8,  31 },
+            { 9,  30 },
+            { 10, 31 },
+            { 11, 30 },
+            { 12, 31 }
+        };
+
+        return monthDayMap.at(month);
+    }
+
+    // Returns the number of calendar weeks spanned by month in the specified year
+    inline static int NumWeeksInMonth(int month, int year)
+    {
+        int days = NumDaysInMonth(month, year);
+        int firstDay = DayOfWeek(1, month, year);
+
+        return static_cast<int>(std::ceil((days + firstDay - 1) / 7.0));
+    }
+
+    // Returns a vector containing dates as they would appear on the calendar for a given week. Populates 0 if there is no day.
+    inline static std::vector<int> CalendarWeek(int week, int startDay, int daysInMonth)
+    {
+        std::vector<int> res(7, 0);
+        int startOfWeek = 7 * (week - 1) + 2 - startDay;
+
+        if (startOfWeek >= 1)
+            res[0] = startOfWeek;
+
+        for (int i = 1; i < 7; ++i)
+        {
+            int day = startOfWeek + i;
+            if ((day >= 1) && (day <= daysInMonth))
+                res[i] = day;
+        }
+
+        return res;
+    }
+
+    constexpr static tm EncodeTimePoint(int dayOfMonth, int month, int year) noexcept
+    {
+        tm res{ };
+        res.tm_isdst = -1;
+        SET_DAY(res, dayOfMonth);
+        SET_MONTH(res, month);
+        SET_YEAR(res, year);
+
+        return res;
+    }
+
+    inline static std::string TimePointToLongString(const tm& timePoint) noexcept
+    {
+        std::string day = std::to_string(GET_DAY(timePoint));
+        std::string month = MONTHS[GET_MONTH_UNSCALED(timePoint)];
+        std::string year = std::to_string(GET_YEAR(timePoint));
+
+        return std::string(day + " " + month + " " + year);
+    }
+
+    inline static tm Today() noexcept
+    {
+        std::chrono::system_clock::time_point now = std::chrono::system_clock::now();
+        std::time_t currentTime = std::chrono::system_clock::to_time_t(now);
+
+        tm res;
+        gmtime_s(&res, &currentTime);
+
+        return res;
+    }
+
+    inline static tm PreviousMonth(const tm& timePoint) noexcept
+    {
+        int month = GET_MONTH(timePoint);
+        int year = GET_YEAR(timePoint);
+
+        if (month == 1)
+        {
+            int newDay = std::min(GET_DAY(timePoint), NumDaysInMonth(12, --year));
+            return EncodeTimePoint(newDay, 12, year);
+        }
+
+        int newDay = std::min(GET_DAY(timePoint), NumDaysInMonth(--month, year));
+        return EncodeTimePoint(newDay, month, year);
+    }
+
+    inline static tm NextMonth(const tm& timePoint) noexcept
+    {
+        int month = GET_MONTH(timePoint);
+        int year = GET_YEAR(timePoint);
+
+        if (month == 12)
+        {
+            int newDay = std::min(GET_DAY(timePoint), NumDaysInMonth(1, ++year));
+            return EncodeTimePoint(newDay, 1, year);
+        }
+
+        int newDay = std::min(GET_DAY(timePoint), NumDaysInMonth(++month, year));
+        return EncodeTimePoint(newDay, month, year);
+    }
+
+    constexpr static bool IsMinDate(const tm& timePoint) noexcept
+    {
+        return (GET_MONTH(timePoint) == 1) && (GET_YEAR(timePoint) == IMGUI_DATEPICKER_YEAR_MIN);
+    }
+
+    constexpr static bool IsMaxDate(const tm& timePoint) noexcept
+    {
+        return (GET_MONTH(timePoint) == 12) && (GET_YEAR(timePoint) == IMGUI_DATEPICKER_YEAR_MAX);
+    }
+
+    static bool ComboBox(const std::string& label, const std::vector<std::string>& items, int& v, ImFont* altFont)
+    {
+        bool res = false;
+
+        ImGui::PushFont(altFont);
+        if (ImGui::BeginCombo(label.c_str(), items[v].c_str()))
+        {
+            for (int i = 0; i < items.size(); ++i)
+            {
+                bool selected = (items[v] == items[i]);
+                if (ImGui::Selectable(items[i].c_str(), &selected))
+                {
+                    v = i;
+                    res = true;
+                }
+
+                if (selected)
+                    ImGui::SetItemDefaultFocus();
+            }
+
+            ImGui::EndCombo();
+        }
+
+        ImGui::PopFont();
+        return res;
+    }
+
+    bool DatePickerEx(const std::string& label, tm& v, ImFont* altFont, bool clampToBorder, float itemSpacing)
+    {
+        bool res = false;
+
+        ImGuiWindow* window = GetCurrentWindow();
+        if (window->SkipItems)
+            return false;
+
+        bool hiddenLabel = label.substr(0, 2) == "##";
+        std::string myLabel = (hiddenLabel) ? label.substr(2) : label;
+
+        if (!hiddenLabel)
+        {
+            Text("%s", label.c_str());
+            SameLine((itemSpacing == 0.0f) ? 0.0f : GetCursorPos().x + itemSpacing);
+        }
+
+        if (clampToBorder)
+            SetNextItemWidth(GetContentRegionAvail().x);
+
+        const ImVec2 windowSize = ImVec2(274.5f, 301.5f);
+        SetNextWindowSize(windowSize);
+
+        if (BeginCombo(std::string("##" + myLabel).c_str(), TimePointToLongString(v).c_str()))
+        {
+            int monthIdx = GET_MONTH_UNSCALED(v);
+            int year = GET_YEAR(v);
+
+            PushItemWidth((GetContentRegionAvail().x * 0.5f));
+
+            if (ComboBox("##CmbMonth_" + myLabel, MONTHS, monthIdx, altFont))
+            {
+                SET_MONTH(v, monthIdx + 1);
+                res = true;
+            }
+
+            PopItemWidth();
+            SameLine();
+            PushItemWidth(GetContentRegionAvail().x);
+
+            if (InputInt(std::string("##IntYear_" + myLabel).c_str(), &year))
+            {
+                SET_YEAR(v, std::min(std::max(IMGUI_DATEPICKER_YEAR_MIN, year), IMGUI_DATEPICKER_YEAR_MAX));
+                res = true;
+            }
+
+            PopItemWidth();
+
+            const float contentWidth = GetContentRegionAvail().x;
+            const float arrowSize = GetFrameHeight();
+            const float arrowButtonWidth = arrowSize * 2.0f + GetStyle().ItemSpacing.x;
+            const float bulletSize = arrowSize - 5.0f;
+            const float bulletButtonWidth = bulletSize + GetStyle().ItemSpacing.x;
+            const float combinedWidth = arrowButtonWidth + bulletButtonWidth;
+            const float offset = (contentWidth - combinedWidth) * 0.5f;
+
+            SetCursorPosX(GetCursorPosX() + offset);
+            PushStyleVar(ImGuiStyleVar_FrameRounding, 20.0f);
+            PushStyleColor(ImGuiCol_Button, ImVec4(0.0f, 0.0f, 0.0f, 0.0f));
+            PushStyleColor(ImGuiCol_Border, ImVec4(0.0f, 0.0f, 0.0f, 0.0f));
+            BeginDisabled(IsMinDate(v));
+
+            if (ArrowButtonEx(std::string("##ArrowLeft_" + myLabel).c_str(), ImGuiDir_Left, ImVec2(arrowSize, arrowSize)))
+            {
+                v = PreviousMonth(v);
+                res = true;
+            }
+
+            EndDisabled();
+            PopStyleColor(2);
+            SameLine();
+            PushStyleColor(ImGuiCol_Button, GetStyleColorVec4(ImGuiCol_Text));
+            SetCursorPosY(GetCursorPosY() + 2.0f);
+
+            if (ButtonEx(std::string("##ArrowMid_" + myLabel).c_str(), ImVec2(bulletSize, bulletSize)))
+            {
+                v = Today();
+                res = true;
+                CloseCurrentPopup();
+            }
+
+            PopStyleColor();
+            SameLine();
+            PushStyleColor(ImGuiCol_Button, ImVec4(0.0f, 0.0f, 0.0f, 0.0f));
+            PushStyleColor(ImGuiCol_Border, ImVec4(0.0f, 0.0f, 0.0f, 0.0f));
+            BeginDisabled(IsMaxDate(v));
+
+            if (ArrowButtonEx(std::string("##ArrowRight_" + myLabel).c_str(), ImGuiDir_Right, ImVec2(arrowSize, arrowSize)))
+            {
+                v = NextMonth(v);
+                res = true;
+            }
+
+            EndDisabled();
+            PopStyleColor(2);
+            PopStyleVar();
+
+            constexpr ImGuiTableFlags TABLE_FLAGS = ImGuiTableFlags_BordersOuter | ImGuiTableFlags_SizingFixedFit |
+                ImGuiTableFlags_NoHostExtendX | ImGuiTableFlags_NoHostExtendY;
+
+            if (BeginTable(std::string("##Table_" + myLabel).c_str(), 7, TABLE_FLAGS, GetContentRegionAvail()))
+            {
+                for (const auto& day : DAYS)
+                    TableSetupColumn(day.c_str(), ImGuiTableColumnFlags_WidthFixed | ImGuiTableColumnFlags_NoHeaderWidth, 30.0f);
+
+                PushStyleColor(ImGuiCol_HeaderHovered, GetStyleColorVec4(ImGuiCol_TableHeaderBg));
+                PushStyleColor(ImGuiCol_HeaderActive, GetStyleColorVec4(ImGuiCol_TableHeaderBg));
+                PushFont(altFont);
+                TableHeadersRow();
+                PopStyleColor(2);
+                PopFont();
+
+                TableNextRow();
+                TableSetColumnIndex(0);
+
+                int month = monthIdx + 1;
+                int firstDayOfMonth = DayOfWeek(1, month, year);
+                int numDaysInMonth = NumDaysInMonth(month, year);
+                int numWeeksInMonth = NumWeeksInMonth(month, year);
+
+                for (int i = 1; i <= numWeeksInMonth; ++i)
+                {
+                    for (const auto& day : CalendarWeek(i, firstDayOfMonth, numDaysInMonth))
+                    {
+                        if (day != 0)
+                        {
+                            PushStyleVar(ImGuiStyleVar_FrameRounding, 20.0f);
+
+                            const bool selected = day == GET_DAY(v);
+                            if (!selected)
+                            {
+                                PushStyleColor(ImGuiCol_Button, ImVec4(0.0f, 0.0f, 0.0f, 0.0f));
+                                PushStyleColor(ImGuiCol_Border, ImVec4(0.0f, 0.0f, 0.0f, 0.0f));
+                            }
+
+                            if (Button(std::to_string(day).c_str(), ImVec2(GetContentRegionAvail().x, GetTextLineHeightWithSpacing() + 5.0f)))
+                            {
+                                v = EncodeTimePoint(day, month, year);
+                                res = true;
+                                CloseCurrentPopup();
+                            }
+
+                            if (!selected)
+                                PopStyleColor(2);
+
+                            PopStyleVar();
+                        }
+
+                        if (day != numDaysInMonth)
+                            TableNextColumn();
+                    }
+                }
+
+                EndTable();
+            }
+
+            EndCombo();
+        }
+
+        return res;
+    }
+
+    bool DatePicker(const std::string& label, tm& v, bool clampToBorder, float itemSpacing)
+    {
+        return DatePickerEx(label, v, nullptr, clampToBorder, itemSpacing);
+    }
+}
diff --git a/libs/ImGuiDatePicker/ImGuiDatePicker.hpp b/libs/ImGuiDatePicker/ImGuiDatePicker.hpp
new file mode 100644
index 0000000..91ed569
--- /dev/null
+++ b/libs/ImGuiDatePicker/ImGuiDatePicker.hpp
@@ -0,0 +1,19 @@
+#pragma once
+#include <imgui.h>
+#include <string>
+
+
+#ifndef IMGUI_DATEPICKER_YEAR_MIN
+    #define IMGUI_DATEPICKER_YEAR_MIN 1900
+#endif // !IMGUI_DATEPICKER_YEAR_MIN
+
+#ifndef IMGUI_DATEPICKER_YEAR_MAX
+    #define IMGUI_DATEPICKER_YEAR_MAX 3000
+#endif // !IMGUI_DATEPICKER_YEAR_MAX
+
+namespace ImGui
+{
+    IMGUI_API bool DatePickerEx(const std::string& label, tm& v, ImFont* altFont, bool clampToBorder = false, float itemSpacing = 130.0f);
+
+    IMGUI_API bool DatePicker(const std::string& label, tm& v, bool clampToBorder = false, float itemSpacing = 130.0f);
+}
diff --git a/libs/ImGuiDatePicker/Images/AltFontDemoImage.png b/libs/ImGuiDatePicker/Images/AltFontDemoImage.png
new file mode 100644
index 0000000..ee12d8d
--- /dev/null
+++ b/libs/ImGuiDatePicker/Images/AltFontDemoImage.png
diff --git a/libs/ImGuiDatePicker/Images/DemoGif.gif b/libs/ImGuiDatePicker/Images/DemoGif.gif
new file mode 100644
index 0000000..7e54364
--- /dev/null
+++ b/libs/ImGuiDatePicker/Images/DemoGif.gif
diff --git a/libs/ImGuiDatePicker/Images/DemoImage.png b/libs/ImGuiDatePicker/Images/DemoImage.png
new file mode 100644
index 0000000..0cd03dc
--- /dev/null
+++ b/libs/ImGuiDatePicker/Images/DemoImage.png
diff --git a/libs/ImGuiDatePicker/LICENSE b/libs/ImGuiDatePicker/LICENSE
new file mode 100644
index 0000000..66090be
--- /dev/null
+++ b/libs/ImGuiDatePicker/LICENSE
@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2024 Adam Foflonker
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
diff --git a/libs/ImGuiDatePicker/README.md b/libs/ImGuiDatePicker/README.md
new file mode 100644
index 0000000..3da59ab
--- /dev/null
+++ b/libs/ImGuiDatePicker/README.md
@@ -0,0 +1,77 @@
+# ImGuiDatePicker
+ImGuiDatePicker is a custom calendar-style date-picker widget for [Dear ImGui](https://github.com/ocornut/imgui) written in `C++20` that can easily be compiled alongside `ImGui` by adding the header and source files to your `ImGui` project.
+
+![DemoGif](Images/DemoGif.gif)
+Font used: [Open Sans](https://fonts.google.com/specimen/Open+Sans)
+
+ImGuiDatePicker uses the `tm` struct for working with dates:
+``` C++
+struct tm
+{
+    int tm_sec;   // seconds after the minute - [0, 60] including leap second
+    int tm_min;   // minutes after the hour - [0, 59]
+    int tm_hour;  // hours since midnight - [0, 23]
+    int tm_mday;  // day of the month - [1, 31]
+    int tm_mon;   // months since January - [0, 11]
+    int tm_year;  // years since 1900
+    int tm_wday;  // days since Sunday - [0, 6]
+    int tm_yday;  // days since January 1 - [0, 365]
+    int tm_isdst; // daylight savings time flag
+};
+```
+## Including
+`IMGUI_DATEPICKER_YEAR_MIN` and `IMGUI_DATEPICKER_YEAR_MAX` should be defined before including [ImGuiDatePicker.hpp](ImGuiDatePicker.hpp). If they are not defined, they will default to `1900` and `3000` respectively.
+``` C++
+// Define the lowest year that the picker can select. In this example, '1970' is the Unix epoch.
+#define IMGUI_DATEPICKER_YEAR_MIN 1970
+// Define the highest year that the picker can select.
+#define IMGUI_DATEPICKER_YEAR_MAX 3000
+#include <ImGuiDatePicker.hpp>
+```
+## Usage
+``` C++
+// Get today's date and store it in a 'tm' struct named 't'
+std::chrono::system_clock::time_point now = std::chrono::system_clock::now();
+std::time_t currentTime = std::chrono::system_clock::to_time_t(now);
+tm t = *std::gmtime(&currentTime);
+
+// Use the picker
+if (ImGui::DatePicker("Date", t))
+{
+    // Perform some event whenever the date 't' is changed
+}
+```
+An `alt font` can also be supplied to the picker by calling `DatePickerEx`. This `alt font` will be used for the picker's days-of-the-week headers and for the month-picker combo box.
+``` C++
+ImFont* boldFont = GetBoldFontFromSomewhere();
+tm t = GetTmFromSomewhere();
+ImGui::DatePickerEx("Date", t, boldFont);
+```
+![AltFontDemoImage](Images/AltFontDemoImage.png)
+
+## License
+ImGuiDatePicker is licensed under the MIT License. See [LICENSE](LICENSE).
+
+```
+MIT License
+
+Copyright (c) 2024 Adam Foflonker
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+```
diff --git a/run.bat b/run.bat
index 7197b94..f557bb4 100644
--- a/run.bat
+++ b/run.bat
@@ -17,11 +17,11 @@ if not exist "%VCVARSALL%" (
 call "%VCVARSALL%" x64
 @set OUT_DIR=build\\
 @set OUT_EXE=accounting
-@set LIB_SOURCES=libs\imgui-1.92.1\backends\imgui_impl_dx11.cpp libs\imgui-1.92.1\backends\imgui_impl_win32.cpp libs\imgui-1.92.1\imgui*.cpp libs\simclist-1.5\simclist.c
+@set LIB_SOURCES=libs\imgui-1.92.1\backends\imgui_impl_dx11.cpp libs\imgui-1.92.1\backends\imgui_impl_win32.cpp libs\imgui-1.92.1\imgui*.cpp libs\simclist-1.5\simclist.c libs\ImGuiDatePicker\*.cpp
 @set SOURCES= src\*.cpp src\ui\*.cpp src\locales\*.cpp
 @set LIBS=opengl32.lib Advapi32.lib Shell32.lib Ole32.lib User32.lib Pathcch.lib D3D11.lib
 @set FLAGS=/nologo /Ob0 /MT /Oy- /Zi /FS /W4 /EHsc /utf-8
-@set INCLUDE_DIRS=/I"libs/imgui-1.92.1" /I"libs/imgui-1.92.1/backends" /I"/" /I"libs/simclist-1.5" /Iinclude
+@set INCLUDE_DIRS=/I"libs/imgui-1.92.1" /I"libs/imgui-1.92.1/backends" /I"/" /I"libs/simclist-1.5" /I"libs/" /Iinclude
 
 cl %FLAGS% %INCLUDE_DIRS% %SOURCES% %LIB_SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fd%OUT_DIR%/vc140.pdb /Fo%OUT_DIR%/ /link %LIBS%
 if "%1"=="-r" call "%OUT_DIR%/%OUT_EXE%.exe"
diff --git a/src/administration.cpp b/src/administration.cpp
index 869855e..a34ece8 100644
--- a/src/administration.cpp
+++ b/src/administration.cpp
@@ -199,6 +199,71 @@ static void administration_create_default_cost_centers()
     ADD_COSTCENTER("costcenter.other_specialized", "OTHR");
 }
 
+static void administration_create_debug_data()
+{
+    #define ADD_CONSUMER(_name, _addr1, _addr2, _cc)\
+    {contact _c = administration_create_empty_contact();\
+    strops_copy(_c.name, _name, sizeof(_c.name));\
+    strops_copy(_c.address.address1, _addr1, sizeof(_c.address.address1));\
+    strops_copy(_c.address.address2, _addr2, sizeof(_c.address.address2));\
+    strops_copy(_c.address.country_code, _cc, sizeof(_c.address.country_code));\
+    _c.type = contact_type::CONTACT_CONSUMER;\
+    administration_create_contact(_c);};
+
+    #define ADD_BUSINESS(_name, _addr1, _addr2, _cc, _tc, _bc)\
+    {contact _c = administration_create_empty_contact();\
+    strops_copy(_c.name, _name, sizeof(_c.name));\
+    strops_copy(_c.address.address1, _addr1, sizeof(_c.address.address1));\
+    strops_copy(_c.address.address2, _addr2, sizeof(_c.address.address2));\
+    strops_copy(_c.address.country_code, _cc, sizeof(_c.address.country_code));\
+    strops_copy(_c.taxid, _tc, sizeof(_c.taxid));\
+    strops_copy(_c.businessid, _bc, sizeof(_c.businessid));\
+    _c.type = contact_type::CONTACT_BUSINESS;\
+    administration_create_contact(_c);};
+
+    #define ADD_PROJECT(_name)\
+    {project _c = administration_create_empty_project();\
+    strops_copy(_c.description, _name, sizeof(_c.description));\
+    administration_create_project(_c);};
+
+    ADD_CONSUMER("Emma Müller", "Hauptstraße 12", "10115 Berlin", "DE");
+    ADD_CONSUMER("Luca Rossi", "Via Roma 45", "00184 Roma", "IT");
+    ADD_CONSUMER("Sofia Garcia", "Calle Mayor 7", "28013 Madrid", "ES");
+    ADD_CONSUMER("Jean Dupont", "10 Rue de la Paix", "75002 Paris", "FR");
+    ADD_CONSUMER("Anna Nowak", "ul. Kwiatowa 3", "00-001 Warszawa", "PL");
+    ADD_CONSUMER("Mikkel Jensen", "Østergade 8", "8000 Aarhus", "DK");
+    ADD_CONSUMER("Maria Svensson", "Kungsgatan 15", "111 22 Stockholm", "SE");
+    ADD_CONSUMER("Péter Kovács", "Fő utca 25", "1051 Budapest", "HU");
+    ADD_CONSUMER("Lucas Silva", "Rua Augusta 100", "1250-001 Lisboa", "PT");
+    ADD_CONSUMER("Isabelle Lefevre", "5 Place Stanislas", "54000 Nancy", "FR");
+
+    ADD_BUSINESS("Schmidt & Co GmbH", "Friedrichstraße 45", "10117 Berlin", "DE", "DE123456789", "HRB123456");
+    ADD_BUSINESS("Bianchi Srl", "Corso Venezia 12", "20121 Milano", "IT", "IT987654321", "MI1234567");
+    ADD_BUSINESS("Fernández y Asociados", "Gran Vía 20", "28013 Madrid", "ES", "ES456789123", "CIFB123456");
+    ADD_BUSINESS("Martin & Partners", "12 Avenue Victor Hugo", "75016 Paris", "FR", "FR321654987", "SIRET123456");
+    ADD_BUSINESS("Zielińska Consulting", "ul. Marszałkowska 10", "00-590 Warszawa", "PL", "PL789123456", "REGON123456");
+    ADD_BUSINESS("Sørensen ApS", "Strøget 3", "1460 København", "DK", "DK654321789", "CVR12345678");
+    ADD_BUSINESS("Johansson AB", "Drottninggatan 22", "111 51 Stockholm", "SE", "SE987654321", "OrgNr1234567");
+    ADD_BUSINESS("Nagy Kft.", "Andrássy út 60", "1062 Budapest", "HU", "HU123987654", "Cégjegyzékszám123");
+    ADD_BUSINESS("Santos Lda.", "Avenida da Liberdade 50", "1250-142 Lisboa", "PT", "PT321789654", "NIPC123456789");
+    ADD_BUSINESS("Dupuis SARL", "8 Rue Saint-Denis", "75001 Paris", "FR", "FR456123789", "SIREN123456");
+    ADD_BUSINESS("Müller & Söhne GmbH", "Leipziger Platz 8", "10117 Berlin", "DE", "DE654987321", "HRB987654");
+    ADD_BUSINESS("Romano Srl", "Via Garibaldi 14", "16124 Genova", "IT", "IT321654987", "GE1239876");
+    ADD_BUSINESS("López Asociados", "Plaza del Pilar 6", "50003 Zaragoza", "ES", "ES789321654", "CIFC654321");
+    ADD_BUSINESS("Laurent & Fils", "15 Boulevard Haussmann", "75009 Paris", "FR", "FR987321654", "SIRET654987");
+    ADD_BUSINESS("Kowalczyk Sp. z o.o.", "ul. Piotrkowska 55", "90-001 Łódź", "PL", "PL123456789", "REGON654321");
+    ADD_BUSINESS("Nielsen ApS", "Nørregade 12", "1165 København", "DK", "DK789456123", "CVR87654321");
+    ADD_BUSINESS("Lindberg AB", "Vasagatan 18", "111 20 Stockholm", "SE", "SE456789123", "OrgNr7654321");
+    ADD_BUSINESS("Szabó Kft.", "Kossuth Lajos tér 1", "1055 Budapest", "HU", "HU987123654", "Cégjegyzékszám654321");
+    ADD_BUSINESS("Costa Lda.", "Rua do Ouro 24", "1100-063 Lisboa", "PT", "PT654123987", "NIPC987654321");
+    ADD_BUSINESS("Moreau SARL", "3 Place de la République", "75011 Paris", "FR", "FR321456987", "SIREN789123");
+
+    ADD_PROJECT("eCommerce");
+    ADD_PROJECT("Retail store #1");
+    ADD_PROJECT("Retail store #2");
+    ADD_PROJECT("Kayak rental");
+}
+
 void administration_create()
 {
     g_administration.next_id = 1;
@@ -220,6 +285,7 @@ void administration_create()
 
     administration_create_default_tax_brackets();
     administration_create_default_cost_centers();
+    administration_create_debug_data();
 }
 
 void administration_destroy()
@@ -232,6 +298,8 @@ void administration_destroy()
 
 bool administration_create_contact(contact data)
 {
+    if (!administration_is_contact_valid(data)) return false;
+    
     contact* new_contact = (contact*)malloc(sizeof(contact));
     memcpy((void*)new_contact, (void*)&data, sizeof(contact));
     list_append(&g_administration.contacts, new_contact);
@@ -250,6 +318,8 @@ bool administration_can_contact_be_deleted(contact data)
 
 bool administration_update_contact(contact data)
 {
+    if (!administration_is_contact_valid(data)) return false;
+
     list_iterator_start(&g_administration.contacts);
     while (list_iterator_hasnext(&g_administration.contacts)) {
         contact* c = (contact *)list_iterator_next(&g_administration.contacts);
@@ -309,6 +379,25 @@ u32 administration_get_contacts(u32 page_index, u32 page_size, contact* buffer)
     return write_cursor;
 }
 
+int administration_get_contact_recommendations(contact* buffer, int buf_size, char* name)
+{
+    int write_cursor = 0;
+    if (name[0] == '\0') return 0;
+
+    list_iterator_start(&g_administration.contacts);
+    while (list_iterator_hasnext(&g_administration.contacts)) {
+        contact c = *(contact *)list_iterator_next(&g_administration.contacts);
+
+        if (strops_stristr(c.name, name)) {
+            buffer[write_cursor++] = c;
+            if (write_cursor >= buf_size) break;
+        }
+    }
+    list_iterator_stop(&g_administration.contacts);
+
+    return write_cursor;
+}
+
 char* administration_get_file_path()
 {
     return g_administration.path;
@@ -348,6 +437,11 @@ void administration_cancel_project(project data)
     administration_update_project(data);
 }
 
+bool administration_is_project_valid(project data)
+{
+    return strlen(data.description) > 0;
+}
+
 char* administration_project_get_status_string(project data)
 {
     switch(data.state)
@@ -362,6 +456,8 @@ char* administration_project_get_status_string(project data)
 
 bool administration_create_project(project data)
 {
+    if (!administration_is_project_valid(data)) return false;
+
     data.state = project_state::PROJECT_RUNNING;
     data.start_date = time(NULL);
     data.end_date = 0;
@@ -376,6 +472,8 @@ bool administration_create_project(project data)
 
 bool administration_update_project(project data)
 {
+    if (!administration_is_project_valid(data)) return false;
+
     list_iterator_start(&g_administration.projects);
     while (list_iterator_hasnext(&g_administration.projects)) {
         project* c = (project *)list_iterator_next(&g_administration.projects);
@@ -572,12 +670,20 @@ static s32 administration_create_sequence_number()
     return g_administration.next_sequence_number;
 }
 
+static time_t administration_get_default_invoice_expire_duration()
+{
+    return (30 * 24 * 60 * 60); // 30 days
+}
+
 invoice administration_create_empty_invoice()
 {
     invoice result;
     memset(&result, 0, sizeof(invoice));
     snprintf(result.id, sizeof(result.id), "I/%d", administration_create_id());
     snprintf(result.sequential_number, sizeof(result.id), "INV%010d", administration_create_sequence_number());
+    result.issued_at = time(NULL);
+    result.delivered_at = time(NULL);
+    result.expires_at = time(NULL) + administration_get_default_invoice_expire_duration();
     return result;
 }
 
diff --git a/src/strops.cpp b/src/strops.cpp
index 42042cb..116eec4 100644
--- a/src/strops.cpp
+++ b/src/strops.cpp
@@ -1,4 +1,5 @@
 #include <string.h>
+#include <ctype.h>
 
 #include "strops.hpp"
 
@@ -15,4 +16,20 @@ size_t strops_copy(char *dst, const char *src, size_t size)
     dst[srclen] = '\0';
 
     return (srclen);
+}
+
+char* strops_stristr(char* haystack, char* needle)
+{
+    do {
+    const char* h = haystack;
+    const char* n = needle;
+    while (tolower((unsigned char) *h) == tolower((unsigned char ) *n) && *n) {
+      h++;
+      n++;
+    }
+    if (*n == 0) {
+      return (char *) haystack;
+    }
+  } while (*haystack++);
+  return 0;
 }
\ No newline at end of file
diff --git a/src/ui/helpers.cpp b/src/ui/helpers.cpp
index a239f4c..4c6647e 100644
--- a/src/ui/helpers.cpp
+++ b/src/ui/helpers.cpp
@@ -65,20 +65,24 @@ void ui_helper_draw_required_tag()
     ImGui::PopStyleColor();
 }
 
-void ui_helper_TextInputWithAutocomplete(const char* label, const char* hint, char* buffer, size_t buf_size,
+int ui_helper_TextInputWithAutocomplete(const char* label, const char* hint, char* buffer, size_t buf_size,
                                 char* suggestions[], int suggestion_count)
 {
+    int result = -1;
     static bool is_open = false;
     ImGui::InputTextWithHint(label, hint, buffer, buf_size);
 
+    if (buffer[0] == '\0' && is_open) is_open = false;
+    if (suggestion_count == 0 && is_open) is_open = false;
+
     bool is_active = ImGui::IsItemActive();
-    if (is_active && buffer[0] != '\0')
+    if (is_active && buffer[0] != '\0' && suggestion_count > 0)
     {
         is_open = true;
     }
 
     if (is_open) {
-        ImGui::BeginChild("autocomplete_popup", ImVec2(0, 100), true);
+        ImGui::BeginChild("autocomplete_popup", ImVec2(0, 10.0f + suggestion_count*23.0f), true);
         {
             ImVec2 win_pos = ImGui::GetWindowPos();
             ImVec2 win_size = ImGui::GetWindowSize();
@@ -97,7 +101,7 @@ void ui_helper_TextInputWithAutocomplete(const char* label, const char* hint, ch
                     // Copy selected suggestion to buffer
                     strops_copy(buffer, suggestions[i], buf_size);
                     buffer[buf_size - 1] = '\0';
-
+                    result = i;
                     is_open = false;
                 }
             }
@@ -105,4 +109,6 @@ void ui_helper_TextInputWithAutocomplete(const char* label, const char* hint, ch
             ImGui::EndChild();
         }
     }
+    return result;
 }
+
diff --git a/src/ui/ui_contacts.cpp b/src/ui/ui_contacts.cpp
index c381db5..d57776e 100644
--- a/src/ui/ui_contacts.cpp
+++ b/src/ui/ui_contacts.cpp
@@ -18,9 +18,8 @@ void ui_setup_contacts()
     memset(&selected_for_removal, 0, sizeof(contact));
 }
 
-void draw_contact_form(contact* buffer, bool viewing_only = false)
+void draw_contact_form_ex(contact* buffer, bool viewing_only = false, bool with_autocomplete = false, bool* on_autocomplete = 0)
 {
-    bool with_autocomplete = false;
     const char* selected_country = NULL;
 
     ImGui::Spacing();
@@ -37,12 +36,26 @@ void draw_contact_form(contact* buffer, bool viewing_only = false)
     // 2. Full name
     ImGui::SetNextItemWidth(widthAvailable*0.5f);
     if (with_autocomplete) {
-         contact autocomplete_list[5];
-        int autocomplete_count = 5;
-        char* autocomplete_strings[5] = { "1", "2", "3", "4", "5" };
+        contact autocomplete_list[5];
+        int autocomplete_count = administration_get_contact_recommendations(autocomplete_list, 5, buffer->name);
+        char* autocomplete_strings[5];
+
+        for (int i = 0; i < autocomplete_count; i++)
+        {
+            autocomplete_strings[i] = autocomplete_list[i].name;
+        }
 
-        ui_helper_TextInputWithAutocomplete(localize("contact.form.fullname"), localize("contact.form.fullname"), 
+        int autocomplete_index = ui_helper_TextInputWithAutocomplete(localize("contact.form.fullname"), localize("contact.form.fullname"), 
                                 buffer->name, IM_ARRAYSIZE(buffer->name), (char**)autocomplete_strings, autocomplete_count);
+
+        if (on_autocomplete) {
+            *on_autocomplete = autocomplete_index != -1;
+        }
+
+        if (autocomplete_index != -1)
+        {
+            memcpy(buffer, &autocomplete_list[autocomplete_index], sizeof(contact));
+        }
     }
     else ImGui::InputTextWithHint(localize("contact.form.fullname"), localize("contact.form.fullname"), buffer->name, IM_ARRAYSIZE(buffer->name));
     ImGui::SameLine();ui_helper_draw_required_tag();
@@ -131,6 +144,12 @@ void draw_contact_form(contact* buffer, bool viewing_only = false)
     if (viewing_only) ImGui::EndDisabled();
 }
 
+void draw_contact_form(contact* buffer, bool viewing_only = false)
+{
+    draw_contact_form_ex(buffer, viewing_only, false, 0);
+}
+
+
 static void draw_contact_list()
 {
     const u32 items_per_page = 50;
diff --git a/src/ui/ui_invoices.cpp b/src/ui/ui_invoices.cpp
index fe4f5a8..8ee099c 100644
--- a/src/ui/ui_invoices.cpp
+++ b/src/ui/ui_invoices.cpp
@@ -1,4 +1,7 @@
 #include <stdio.h>
+#include <time.h>
+
+#include "ImGuiDatePicker/ImGuiDatePicker.hpp"
 
 #include "strops.hpp"
 #include "ui.hpp"
@@ -9,7 +12,7 @@
 static view_state current_view_state = view_state::LIST;
 static invoice active_invoice;
 
-extern void draw_contact_form(contact* buffer, bool viewing_only = false);
+void draw_contact_form_ex(contact* buffer, bool viewing_only = false, bool with_autocomplete = false, bool* on_autocomplete = 0);
 
 void ui_setup_invoices()
 {
@@ -17,23 +20,16 @@ void ui_setup_invoices()
     active_invoice = administration_create_empty_invoice();
 }
 
-bool draw_invoice_form(invoice* buffer, bool back_button_enabled = true, bool viewing_only = false)
+void draw_invoice_form(invoice* buffer, bool viewing_only = false)
 {
-    if (back_button_enabled)
-    {
-        if (ImGui::Button(localize("form.back"))) {
-            current_view_state = view_state::LIST;
-            return false;
-        }
-    }
-    ImGui::Spacing();
-    float widthAvailable = ImGui::GetContentRegionAvail().x;
+    //float widthAvailable = ImGui::GetContentRegionAvail().x;
+    ImGui::BeginDisabled();
 
     // 1. Identifier
-    //ImGui::BeginDisabled();
     //ImGui::SetNextItemWidth(widthAvailable*0.2f);
     //ImGui::InputText(localize("contact.form.identifier"), buffer->id, IM_ARRAYSIZE(buffer->id));
-    
+    if (!viewing_only) ImGui::EndDisabled();
+
     // 2. Sequential number
     ImGui::Text("Invoice number: %s", buffer->sequential_number);
 
@@ -42,20 +38,54 @@ bool draw_invoice_form(invoice* buffer, bool back_button_enabled = true, bool vi
 
     ImGui::Separator();
 
+    // 4. Customer information
     ImGui::Text("Customer information");
-    draw_contact_form(&buffer->customer);
-    strops_copy(buffer->customer_id, buffer->customer.id, sizeof(buffer->customer_id));
+    bool on_autocomplete;
+    draw_contact_form_ex(&buffer->customer, false, true, &on_autocomplete);
+
+    if (on_autocomplete) {
+        strops_copy(buffer->customer_id, buffer->customer.id, sizeof(buffer->customer_id));
+    }
 
     ImGui::Separator();
 
+    // 5. Invoice issued at
+    ImGui::BeginDisabled();
+    tm issued_at_date = *gmtime(&buffer->issued_at);
+    if (ImGui::DatePicker("##issuedAt", issued_at_date))
+    {
+        buffer->issued_at = mktime(&issued_at_date);
+    }
+    ImGui::SameLine();
+    ImGui::Text("Invoice issued at");
+    ImGui::EndDisabled();
+
+    // 6. Invoice expires at
+    ImGui::BeginDisabled();
+    tm expires_at_date = *gmtime(&buffer->expires_at);
+    if (ImGui::DatePicker("##expiresAt", expires_at_date))
+    {
+        buffer->expires_at = mktime(&expires_at_date);
+    }
+    ImGui::SameLine();
+    ImGui::Text("Invoice expires at");
+    ImGui::EndDisabled();
+
+    // 7. Product/service delivered at
+    tm delivered_at_date = *gmtime(&buffer->delivered_at);
+    if (ImGui::DatePicker("##deliveredAt", delivered_at_date))
+    {
+        buffer->delivered_at = mktime(&delivered_at_date);
+    }
+    ImGui::SameLine();
+    ImGui::Text("Product/service delivered at");
+
     //ImGui::SetNextItemWidth(widthAvailable*0.5f);
     //ImGui::InputTextWithHint("Invoice number", "Invoice number", buffer->sequential_number, IM_ARRAYSIZE(buffer->sequential_number));
     //ImGui::SameLine();ui_helper_draw_required_tag();
     
     
-    //if (!viewing_only) ImGui::EndDisabled();
-
-    return false;
+    if (viewing_only) ImGui::EndDisabled();
 }
 
 void draw_invoices_list()
@@ -75,12 +105,17 @@ void ui_draw_invoices()
     switch(current_view_state)
     {
         case view_state::LIST: draw_invoices_list(); break;
-        case view_state::CREATE: 
-            if (draw_invoice_form(&active_invoice)) 
-            {
-                //administration_create_invoice(active_invoice);
+        case view_state::CREATE:
+
+            if (ImGui::Button(localize("form.back"))) {
                 current_view_state = view_state::LIST;
-            } 
+            }
+            draw_invoice_form(&active_invoice);
+
+            //if () {
+                //administration_create_invoice(active_invoice);
+                //current_view_state = view_state::LIST;
+            //} 
             break;
         case view_state::EDIT: break;
         case view_state::VIEW: break;
diff --git a/src/ui/ui_projects.cpp b/src/ui/ui_projects.cpp
index 5cb412f..3c550a2 100644
--- a/src/ui/ui_projects.cpp
+++ b/src/ui/ui_projects.cpp
@@ -45,7 +45,7 @@ static void draw_project_form()
     if (viewing_only) ImGui::EndDisabled();
 
     if (!viewing_only) {
-        bool can_save = strlen(active_project.description) > 0;
+        bool can_save = administration_is_project_valid(active_project);
 
         if (!can_save) ImGui::BeginDisabled();
         // Save button