wip:

ats0002/ats0002.c

@@ -1,4 +1,6 @@
 #include "ats0002.h"
+#include <stdarg.h>
+#include <time.h>
 
 /**
  * @brief Normalize the decimal separator in a string from comma to dot.
@@ -60,6 +62,31 @@ static void _get_double_in_range(double *result, double min, double max, const c
  * @param airflow Pointer to the current airflow value
  * @param data Pointer to air passage data containing anchor points (must not be NULL)
  */
+/**
+ * @brief Get the current date as a formatted string (YYYY-MM-DD).
+ *
+ * @param buffer Destination buffer (at least 11 bytes)
+ */
+static void _get_date_string(char *buffer);
+
+/**
+ * @brief Save the test report to a minimal PDF file.
+ *
+ * @see save_report_to_pdf (public API)
+ */
+static void _save_report_to_pdf_impl(const char *heat_exchanger_name,
+                                     const char *part_number,
+                                     const char *side_name,
+                                     double airflow,
+                                     double airflow_pressure,
+                                     const char *unit,
+                                     const double *barometric_pressure,
+                                     const double *airflow_temperature,
+                                     const double *corrected_airflow_pressure,
+                                     double pressure_drop_limit,
+                                     const char *test_result,
+                                     bool recalculated_required);
+
 static void _get_log_interpolated_airflow_pressure_drop_limit(double *limit, const double *airflow, const air_passage_data_t *data);
 
 /**
@@ -331,3 +358,238 @@ static void _calculate_density_corrected_pressure(double *corrected_airflow_pres
     double value_7 = (0.28443 * value_5) / value_6;
     *corrected_airflow_pressure = *airflow_pressure * value_7;
 }
+
+void get_yes_no(bool *answer, const char *prompt)
+{
+    printf("%s (y/n):\n", prompt);
+    char buf[64];
+    for (;;)
+    {
+        printf("> ");
+        fflush(stdout);
+        if (fgets(buf, sizeof(buf), stdin) == NULL)
+        {
+            *answer = false;
+            return;
+        }
+        buf[strcspn(buf, "\n")] = '\0';
+        if (strcmp(buf, "q") == 0 || strcmp(buf, "Q") == 0)
+        {
+            *answer = false;
+            return;
+        }
+        if (strcmp(buf, "y") == 0 || strcmp(buf, "Y") == 0 ||
+            strcmp(buf, "yes") == 0 || strcmp(buf, "Yes") == 0 || strcmp(buf, "YES") == 0)
+        {
+            *answer = true;
+            return;
+        }
+        if (strcmp(buf, "n") == 0 || strcmp(buf, "N") == 0 ||
+            strcmp(buf, "no") == 0 || strcmp(buf, "No") == 0 || strcmp(buf, "NO") == 0)
+        {
+            *answer = false;
+            return;
+        }
+        printf("Please enter 'y' or 'n':\n");
+    }
+}
+
+/* ======================== PDF Report Generation ======================== */
+
+/**
+ * @brief Escape special characters in PDF string literals.
+ *
+ * PDF strings require backslash-escaping for: \ ( )
+ *
+ * @param[out] dst Destination buffer
+ * @param[in] dst_size Size of destination buffer
+ * @param[in] src Source string
+ */
+static void _pdf_escape_string(char *dst, size_t dst_size, const char *src)
+{
+    size_t di = 0;
+    for (size_t si = 0; src[si] != '\0' && di + 2 < dst_size; si++)
+    {
+        char c = src[si];
+        if (c == 0x5C || c == 0x28 || c == 0x29)
+        {
+            dst[di++] = 0x5C;
+        }
+        dst[di++] = c;
+    }
+    dst[di] = '\0';
+}
+
+/**
+ * @brief Get the current date as a formatted string (YYYY-MM-DD).
+ *
+ * @param buffer Destination buffer (at least 11 bytes)
+ */
+static void _get_date_string(char *buffer)
+{
+    time_t now = time(NULL);
+    struct tm *t = localtime(&now);
+    snprintf(buffer, 11, "%04d-%02d-%02d", t->tm_year + 1900, t->tm_mon + 1, t->tm_mday);
+}
+
+/**
+ * @brief Build a PDF content stream line for a text label.
+ *
+ * Appends a BT/ET text block to the stream buffer and advances the y position.
+ *
+ * @param stream_buf Content stream buffer
+ * @param stream_size Size of the content stream buffer
+ * @param slen Current stream length (updated in-place)
+ * @param y Current y position (updated in-place: decremented by 18)
+ * @param font_size Font size in points
+ * @param fmt printf-style format string for the text
+ */
+static void _pdf_add_text_line(char *stream_buf, size_t stream_size, int *slen, double *y,
+                               int font_size, const char *fmt, ...)
+{
+    char raw_line[512];
+    va_list args;
+    va_start(args, fmt);
+    vsnprintf(raw_line, sizeof(raw_line), fmt, args);
+    va_end(args);
+
+    char escaped[1024];
+    _pdf_escape_string(escaped, sizeof(escaped), raw_line);
+
+    *slen += snprintf(stream_buf + *slen, stream_size - (size_t)*slen,
+                      "BT\n/F1 %d Tf\n50 %.0f Td\n(%s) Tj\nET\n",
+                      font_size, *y, escaped);
+    *y -= 18;
+}
+
+/**
+ * Minimal PDF generator. Creates a single-page PDF with text content.
+ * Uses PDF 1.4 format with Type1 font (Helvetica). No external dependencies.
+ */
+static void _save_report_to_pdf_impl(const char *heat_exchanger_name,
+                                     const char *part_number,
+                                     const char *side_name,
+                                     double airflow,
+                                     double airflow_pressure,
+                                     const char *unit,
+                                     const double *barometric_pressure,
+                                     const double *airflow_temperature,
+                                     const double *corrected_airflow_pressure,
+                                     double pressure_drop_limit,
+                                     const char *test_result,
+                                     bool recalculated_required)
+{
+    char date_str[11];
+    _get_date_string(date_str);
+
+    /* Build filename: <P/N>_<YYYY-MM-DD>.pdf in project root */
+    char filename[256];
+    snprintf(filename, sizeof(filename), "%s_%s.pdf", part_number, date_str);
+
+    FILE *f = fopen(filename, "wb");
+    if (!f)
+    {
+        printf("Error: Cannot create PDF file '%s'\n", filename);
+        return;
+    }
+
+    /* --- Build content stream in memory --- */
+    char stream_buf[4096];
+    int slen = 0;
+    double y = 750;
+
+    /* Title */
+    _pdf_add_text_line(stream_buf, sizeof(stream_buf), &slen, &y, 14, "%s", heat_exchanger_name);
+    /* Separator */
+    slen += snprintf(stream_buf + slen, sizeof(stream_buf) - (size_t)slen,
+                     "50 %.0f m 550 %.0f l 0.5 0.5 0.5 RG 1 w S\n", y + 8, y + 8);
+    y -= 8;
+
+    _pdf_add_text_line(stream_buf, sizeof(stream_buf), &slen, &y, 11, "P/N:  %s", part_number);
+    _pdf_add_text_line(stream_buf, sizeof(stream_buf), &slen, &y, 11, "Side: %s", side_name);
+    _pdf_add_text_line(stream_buf, sizeof(stream_buf), &slen, &y, 11, "Airflow:                   %0.2f LB/MIN", airflow);
+    _pdf_add_text_line(stream_buf, sizeof(stream_buf), &slen, &y, 11, "Static inlet pressure:     %0.2f %s", airflow_pressure, unit);
+
+    if (recalculated_required)
+    {
+        _pdf_add_text_line(stream_buf, sizeof(stream_buf), &slen, &y, 11, "Barometric pressure:       %0.2f MBAR", *barometric_pressure);
+        _pdf_add_text_line(stream_buf, sizeof(stream_buf), &slen, &y, 11, "Airflow temperature:       %0.2f C", *airflow_temperature);
+        _pdf_add_text_line(stream_buf, sizeof(stream_buf), &slen, &y, 11, "Corrected static pressure: %0.2f %s", *corrected_airflow_pressure, unit);
+    }
+
+    _pdf_add_text_line(stream_buf, sizeof(stream_buf), &slen, &y, 11, "Max allowed pressure drop: %0.2f %s", pressure_drop_limit, unit);
+    y -= 6;
+    _pdf_add_text_line(stream_buf, sizeof(stream_buf), &slen, &y, 11, "Test result:               %s", test_result);
+
+    /* Footer */
+    y -= 6;
+    _pdf_add_text_line(stream_buf, sizeof(stream_buf), &slen, &y, 8, "Report date: %s", date_str);
+
+    unsigned int stream_len = (unsigned int)slen;
+
+    /* --- Write PDF file --- */
+    /* Object layout:
+     *   1 0 obj — Catalog
+     *   2 0 obj — Pages
+     *   3 0 obj — Page
+     *   4 0 obj — Content stream
+     *   5 0 obj — Font
+     */
+    fprintf(f, "%%PDF-1.4\n");
+
+    unsigned int offsets[6] = {0};
+
+    offsets[1] = (unsigned int)ftell(f);
+    fprintf(f, "1 0 obj\n<< /Type /Catalog /Pages 2 0 R >>\nendobj\n");
+
+    offsets[2] = (unsigned int)ftell(f);
+    fprintf(f, "2 0 obj\n<< /Type /Pages /Kids [3 0 R] /Count 1 >>\nendobj\n");
+
+    offsets[3] = (unsigned int)ftell(f);
+    fprintf(f, "3 0 obj\n<< /Type /Page /Parent 2 0 R /MediaBox [0 0 612 792] "
+               "/Contents 4 0 R /Resources << /Font << /F1 5 0 R >> >> >>\nendobj\n");
+
+    offsets[4] = (unsigned int)ftell(f);
+    fprintf(f, "4 0 obj\n<< /Length %u >>\nstream\n", stream_len);
+    fwrite(stream_buf, 1, stream_len, f);
+    fprintf(f, "\nendstream\nendobj\n");
+
+    offsets[5] = (unsigned int)ftell(f);
+    fprintf(f, "5 0 obj\n<< /Type /Font /Subtype /Type1 /BaseFont /Helvetica /Encoding /WinAnsiEncoding >>\nendobj\n");
+
+    /* Cross-reference table */
+    unsigned int xref_offset = (unsigned int)ftell(f);
+    fprintf(f, "xref\n");
+    fprintf(f, "0 6\n");
+    fprintf(f, "0000000000 65535 f \n");
+    for (int i = 1; i <= 5; i++)
+    {
+        fprintf(f, "%010u 00000 n \n", offsets[i]);
+    }
+
+    fprintf(f, "trailer\n<< /Size 6 /Root 1 0 R >>\nstartxref\n");
+    fprintf(f, "%u\n%%%%EOF\n", xref_offset);
+
+    fclose(f);
+    printf("Report saved to: %s\n", filename);
+}
+
+void save_report_to_pdf(const char *heat_exchanger_name,
+                        const char *part_number,
+                        const char *side_name,
+                        double airflow,
+                        double airflow_pressure,
+                        const char *unit,
+                        const double *barometric_pressure,
+                        const double *airflow_temperature,
+                        const double *corrected_airflow_pressure,
+                        double pressure_drop_limit,
+                        const char *test_result,
+                        bool recalculated_required)
+{
+    _save_report_to_pdf_impl(heat_exchanger_name, part_number, side_name,
+                             airflow, airflow_pressure, unit,
+                             barometric_pressure, airflow_temperature,
+                             corrected_airflow_pressure, pressure_drop_limit,
+                             test_result, recalculated_required);
+}

ats0002/ats0002.h

@@ -205,3 +205,46 @@ void get_airflow_temperature(double *airflow_temperature, const air_passage_data
  * @param[in] data Pointer to air passage data containing operational limits (must not be NULL)
  */
 void get_pressure_drop(double *pressure_drop_limit, const double *airflow, const double *airflow_pressure, double *corrected_airflow_pressure, const double *barometric_pressure, const double *airflow_temperature, const air_passage_data_t *data);
+
+/**
+ * @brief Save the test report to a PDF file in the project root.
+ *
+ * Generates a minimal PDF file containing the test summary with P/N and date.
+ * The file is saved as "<P/N>_YYYY-MM-DD.pdf" in the project root directory.
+ *
+ * @param heat_exchanger_name Full heat exchanger description string
+ * @param part_number Part number string (e.g. "182820-1")
+ * @param side_name Air passage side description string
+ * @param airflow Airflow value in LB/MIN
+ * @param airflow_pressure Static inlet pressure value
+ * @param unit Pressure unit string ("KPA" or "PSIG")
+ * @param barometric_pressure Barometric pressure value (may be NULL if not applicable)
+ * @param airflow_temperature Airflow temperature value (may be NULL if not applicable)
+ * @param corrected_airflow_pressure Corrected static inlet pressure (may be NULL if not applicable)
+ * @param pressure_drop_limit Max allowed pressure drop limit
+ * @param test_result "PASSED" or "FAILED"
+ * @param recalculated_required Flag indicating if recalculation was performed
+ */
+void save_report_to_pdf(const char *heat_exchanger_name,
+                        const char *part_number,
+                        const char *side_name,
+                        double airflow,
+                        double airflow_pressure,
+                        const char *unit,
+                        const double *barometric_pressure,
+                        const double *airflow_temperature,
+                        const double *corrected_airflow_pressure,
+                        double pressure_drop_limit,
+                        const char *test_result,
+                        bool recalculated_required);
+
+/**
+ * @brief Ask the user a yes/no question.
+ *
+ * Prompts the user with a yes/no question. Returns true for "yes", false for "no".
+ * Handles EXIT command.
+ *
+ * @param[out] answer Pointer to store the answer (true=yes, false=no, EXIT=quit)
+ * @param[in] prompt Question to display
+ */
+void get_yes_no(bool *answer, const char *prompt);

heat_exchander_airflow_pressure_drop.c

@@ -95,6 +95,26 @@ int main(void)
         printf("Test result:                          %s\n", test_pressure <= pressure_drop_limit ? "PASSED" : "FAILED");
         printf("***************************************************\n");
         printf("\n");
+        /* Offer to save report as PDF */
+        bool save_pdf = false;
+        get_yes_no(&save_pdf, "Save report to PDF?");
+        if (save_pdf)
+        {
+            save_report_to_pdf(
+                he->heat_exchanger_description,
+                he->heat_exchanger_type_data[part_number].part_number_description,
+                hetd->air_passages_data[air_passage_number].air_passage_description,
+                airflow,
+                airflow_pressure,
+                unit,
+                apd->recalculated_required ? &barometric_pressure : NULL,
+                apd->recalculated_required ? &airflow_temperature : NULL,
+                apd->recalculated_required ? &corrected_airflow_pressure : NULL,
+                pressure_drop_limit,
+                test_pressure <= pressure_drop_limit ? "PASSED" : "FAILED",
+                apd->recalculated_required);
+        }
+        printf("\n");
         uint16_t command = 0;
         get_user_command(&command);
         EXIT_CHECK(command);