invoice: render the document as PDF

1 files changed, 205 insertions, 0 deletions

diff --git a/tests/invoice_check.c b/tests/invoice_check.c
new file mode 100644
index 0000000..46b1621
--- /dev/null
+++ b/tests/invoice_check.c
@@ -0,0 +1,205 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "invoice.h"
+
+static int failures;
+
+static void check(int cond, const char *what)
+{
+    if (!cond) {
+        printf("FAIL %s\n", what);
+        failures++;
+    } else {
+        printf("ok %s\n", what);
+    }
+}
+
+static void eq64(const char *what, int64_t got, int64_t want)
+{
+    if (got != want) {
+        printf("FAIL %s: got %lld want %lld\n", what, (long long)got,
+               (long long)want);
+        failures++;
+    } else {
+        printf("ok %s: %lld\n", what, (long long)got);
+    }
+}
+
+static const struct invoice_line synthetic_lines[] = {
+    { "", "Utvecklingsarbete\nPeriod 2026-01-01 tom 2026-01-31", 61000, "tim",
+      120000, 7320000, "", "25" },
+    { "A-1", "Konsult", 12500, "tim", 80000, 1000000, "Omvänd moms", "rc" },
+};
+
+static void make_doc(struct invoice_doc *d)
+{
+    memset(d, 0, sizeof *d);
+    d->seller.name = "Testleverantör AB";
+    d->seller.address = "Testvägen 1";
+    d->seller.postal_code = "12345";
+    d->seller.city = "Teststad";
+    d->seller.phone = "+46(0)70 - 00 00 000";
+    d->seller.email = "test@example.invalid";
+    d->seller.org_nr = "559000-0000";
+    d->seller.vat_nr = "SE559000000001";
+    d->seller.bankgiro = "0000-0000";
+    d->customer.name = "Testkund AB";
+    d->customer.address = "Kundgatan 2";
+    d->customer.postal_code = "54321";
+    d->customer.city = "Kundstad";
+    d->customer.vat_nr = "SE556000000001";
+    d->number = 1001;
+    d->ocr = "100102";
+    d->invoice_date = "2026-02-01";
+    d->due_date = "2026-03-03";
+    d->delivery_date = "2026-02-01";
+    d->our_ref = "Test Person";
+    d->your_ref = "Kund Person";
+    d->payment_days = 30;
+    d->lines = synthetic_lines;
+    d->nlines = 2;
+}
+
+static void test_totals(void)
+{
+    static const struct invoice_line lines[] = {
+        { "", "a", 1000, "st", 1000, 100000, "", "25" },
+        { "", "b", 1000, "st", 1000, 50000, "", "12" },
+        { "", "c", 1000, "st", 1000, 10000, "", "6" },
+        { "", "d", 1000, "st", 1000, 25000, "", "rc" },
+        { "", "e", 1000, "st", 1000, 15000, "", "0" },
+        { "", "f", 1000, "st", 1000, 4000, "", "eu" },
+    };
+    struct invoice_doc d;
+    struct invoice_totals t;
+
+    make_doc(&d);
+    d.lines = lines;
+    d.nlines = sizeof lines / sizeof lines[0];
+    invoice_totals(&d, &t);
+    eq64("net", t.net_ore, 204000);
+    eq64("vat", t.vat_ore, 31600);
+    eq64("total", t.total_ore, 235600);
+    eq64("net 25", t.net_25, 100000);
+    eq64("net 12", t.net_12, 50000);
+    eq64("net 6", t.net_6, 10000);
+    eq64("net free", t.net_free, 44000);
+
+    {
+        static const struct invoice_line half[] = {
+            { "", "half", 1000, "st", 100, 50, "", "25" },
+        };
+
+        d.lines = half;
+        d.nlines = 1;
+        invoice_totals(&d, &t);
+        eq64("vat half up", t.vat_ore, 13);
+    }
+
+    invoice_totals(NULL, &t);
+    eq64("null doc net", t.net_ore, 0);
+    eq64("null doc total", t.total_ore, 0);
+    invoice_totals(&d, NULL);
+    check(1, "null totals accepted");
+}
+
+static void test_ocr(void)
+{
+    check(invoice_ocr_check("7992739871") == 3, "luhn canonical");
+    check(invoice_ocr_check("804") == 5, "luhn 804");
+    check(invoice_ocr_check("13006") == 2, "luhn 13006");
+    check(invoice_ocr_check("23506") == 9, "luhn 23506");
+    check(invoice_ocr_check("0") == 0, "luhn zero");
+    check(invoice_ocr_check("") == 0, "luhn empty");
+    check(invoice_ocr_check("12a") == -1, "luhn non-digit");
+    check(invoice_ocr_check(NULL) == -1, "luhn null");
+}
+
+static int contains(const unsigned char *data, size_t len, const char *needle)
+{
+    size_t n = strlen(needle);
+
+    if (n > len)
+        return 0;
+    for (size_t i = 0; i + n <= len; i++)
+        if (memcmp(data + i, needle, n) == 0)
+            return 1;
+    return 0;
+}
+
+static void test_render(const char *path)
+{
+    struct invoice_doc d;
+    struct invoice_totals t;
+    unsigned char *data = NULL;
+    size_t len = 0;
+
+    make_doc(&d);
+    invoice_totals(&d, &t);
+    eq64("synthetic net", t.net_ore, 8320000);
+    eq64("synthetic vat", t.vat_ore, 1830000);
+    eq64("synthetic total", t.total_ore, 10150000);
+
+    check(invoice_render_pdf(&d, &data, &len) == 0, "render returns 0");
+    check(data != NULL && len > 1000, "render bytes");
+    if (data) {
+        check(memcmp(data, "%PDF-1.4", 8) == 0, "render header");
+        check(contains(data, len, "Testleverant"), "render seller text");
+        check(contains(data, len, "Testkund AB"), "render customer text");
+        check(contains(data, len, "Summa att betala SEK"), "render summary");
+        check(contains(data, len, "Test Person"), "render our ref");
+    }
+    if (path && data) {
+        FILE *f = fopen(path, "wb");
+
+        if (!f) {
+            printf("FAIL cannot write %s\n", path);
+            failures++;
+        } else {
+            fwrite(data, 1, len, f);
+            fclose(f);
+            printf("wrote %s (%zu bytes)\n", path, len);
+        }
+    }
+    free(data);
+
+    {
+        unsigned char *bad = NULL;
+        size_t n = 0;
+
+        check(invoice_render_pdf(NULL, &bad, &n) == -1, "render null doc");
+        check(bad == NULL && n == 0, "render null clears out");
+        check(invoice_render_pdf(&d, NULL, &n) == -1, "render null out");
+        check(invoice_render_pdf(&d, &bad, NULL) == -1, "render null len");
+        d.lines = NULL;
+        d.nlines = 1;
+        check(invoice_render_pdf(&d, &bad, &n) == -1, "render null lines");
+    }
+    {
+        struct invoice_doc many;
+        static struct invoice_line rows[40];
+        unsigned char *bad = NULL;
+        size_t n = 0;
+
+        make_doc(&many);
+        for (size_t i = 0; i < 40; i++)
+            rows[i] = synthetic_lines[0];
+        many.lines = rows;
+        many.nlines = 40;
+        check(invoice_render_pdf(&many, &bad, &n) == -1, "render overflows");
+    }
+}
+
+int main(int argc, char **argv)
+{
+    test_totals();
+    test_ocr();
+    test_render(argc > 1 ? argv[1] : NULL);
+    if (failures)
+        printf("%d failures\n", failures);
+    else
+        puts("all ok");
+    return failures ? 1 : 0;
+}