Add human durations and body metric graphs

CHANGELOG.md

@@ -37,8 +37,27 @@ Added:
 
 Planned next:
 
-- human duration input such as `1:30`, `1m30`, `2m`, and `45s`;
+- human duration input such as `1:30`, `1m30`, `2m`, and `45s` (implemented);
-- automatic minute/second display formatting;
+- automatic minute/second display formatting (implemented);
-- history graphs for all body measurements;
+- history graphs for all body measurements (implemented);
-- left/right asymmetry summaries.
+- left/right asymmetry summaries (implemented).
 <!-- TRAINLOG_TUI_V02_CHANGELOG _END -->
+
+<!-- TRAINLOG_GLOBAL_BODY_GRAPH_CHANGELOG -->
+### Current TUI checkpoint
+
+Implemented:
+- human duration input;
+- human minute/second display;
+- graphs for every persisted body metric;
+- recent values for every body metric;
+- left/right asymmetry summaries.
+
+Next:
+- normalized global body overlay graph;
+- metric legend using both colors and symbols;
+- percentage evolution summary;
+- richer dashboard weight graph;
+- dashboard previous-weight delta and min/max;
+- compact body/asymmetry dashboard summary.
+<!-- TRAINLOG_GLOBAL_BODY_GRAPH_CHANGELOG _END -->

docs/reviews/tui_duration_body_checkpoint.md

@@ -0,0 +1,85 @@
+# Human Duration and Body Graph Checkpoint
+
+## Status
+
+```text
+FIRST_USABLE_TUI=PASS
+TUI_V0_2_POLISH=IMPLEMENTED
+TUI_SESSION_DETAILS=IMPLEMENTED
+TUI_DURATION_HUMAN_INPUT=IMPLEMENTED
+TUI_BODY_METRIC_GRAPHS=IMPLEMENTED
+GATE_2=IN_PROGRESS
+TRAINLOG_FORMAT_V1=FROZEN
+```
+
+## Implemented
+
+### Human duration entry
+
+Accepted examples:
+
+```text
+90
+90s
+1:30
+1m30
+1m30s
+2m
+45s
+2:05
+```
+
+Persistence remains canonical seconds.
+Display uses human minute/second formatting.
+
+### Body tracking
+
+`F4 Corps` now provides per-metric history for weight, neck, shoulders, chest,
+waist, hips, left/right arm, left/right forearm, left/right thigh and
+left/right calf.
+
+Each metric has latest value, first value, change, graph and recent dated
+values. Paired limbs expose same-observation asymmetry.
+
+## Next visualization contract
+
+### Global body graph
+
+All available body series are overlaid after normalizing each metric's first
+real value to 100. The global graph is display-only.
+
+### Dashboard graph v2
+
+The home screen remains compact but gains:
+- current weight;
+- first-to-current delta;
+- previous-to-current delta;
+- min/max;
+- richer recent weight graph;
+- latest waist;
+- compact asymmetry status.
+
+## Validation before push
+
+```bash
+meson compile -C build
+meson test -C build --print-errorlogs
+python tools/validate_json.py
+python tools/validate_import_contract.py
+git diff --check
+git diff --cached --check
+```
+
+Sanitizer validation:
+
+```bash
+meson compile -C build-asan
+meson test -C build-asan --print-errorlogs
+```
+
+## Next
+
+```text
+TUI_GLOBAL_BODY_OVERLAY
+DASHBOARD_GRAPH_V2
+```

docs/reviews/tui_duration_body_graphs.md

@@ -0,0 +1,18 @@
+# Human Durations and Body Metric Graphs
+
+## Status
+
+```text
+TUI_DURATION_HUMAN_INPUT=IMPLEMENTED
+TUI_BODY_METRIC_GRAPHS=IMPLEMENTED
+TRAINLOG_FORMAT_V1=FROZEN
+```
+
+Durations accept `90`, `90s`, `1:30`, `1m30`, `1m30s`, `2m`, `45s`
+and `2:05`, while persistence remains integer seconds.
+
+F4 now browses all frozen body measurements with left/right navigation,
+latest/first/change summaries, a graph, recent values, and same-observation
+left/right asymmetry for arms, forearms, thighs, and calves.
+
+No database migration and no JSON v1 change are required.

docs/roadmap.md

@@ -51,8 +51,8 @@ Current state:
 FIRST_USABLE_TUI=PASS
 TUI_V0_2_POLISH=IMPLEMENTED
 TUI_SESSION_DETAILS=IMPLEMENTED
-TUI_DURATION_HUMAN_INPUT=NEXT
+TUI_DURATION_HUMAN_INPUT=IMPLEMENTED
-TUI_BODY_METRIC_GRAPHS=NEXT
+TUI_BODY_METRIC_GRAPHS=IMPLEMENTED
 GATE_2=IN_PROGRESS
 TRAINLOG_FORMAT_V1=FROZEN
 ```
@@ -83,3 +83,34 @@ Next implementation slice:
 
 No incompatible change to frozen Trainlog JSON v1 is required.
 <!-- TRAINLOG_TUI_V02_ROADMAP _END -->
+
+<!-- TRAINLOG_GLOBAL_BODY_GRAPH_ROADMAP -->
+## Next TUI visualization slice
+
+Canonical state after the current checkpoint:
+
+```text
+FIRST_USABLE_TUI=PASS
+TUI_V0_2_POLISH=IMPLEMENTED
+TUI_SESSION_DETAILS=IMPLEMENTED
+TUI_DURATION_HUMAN_INPUT=IMPLEMENTED
+TUI_BODY_METRIC_GRAPHS=IMPLEMENTED
+TUI_GLOBAL_BODY_OVERLAY=NEXT
+DASHBOARD_GRAPH_V2=NEXT
+GATE_2=IN_PROGRESS
+TRAINLOG_FORMAT_V1=FROZEN
+```
+
+Next deliverables:
+1. normalized global body graph in `F4`;
+2. color + symbol identity for every overlaid metric;
+3. global percent-change summary;
+4. richer home weight graph;
+5. previous-measurement delta on dashboard;
+6. dashboard min/max weight;
+7. latest waist summary when available;
+8. compact asymmetry warning when relevant.
+
+No database schema migration is expected.
+No Trainlog JSON v1 change is expected.
+<!-- TRAINLOG_GLOBAL_BODY_GRAPH_ROADMAP _END -->

docs/tui.md

@@ -267,7 +267,7 @@ Inside one workout, left/right or up/down changes the selected exercise.
 Assistance remains direction-aware: more assistance kilograms mean more help,
 not greater strength.
 
-## 18. Duration input and display — next implementation slice
+## 18. Duration input and display — implemented
 
 Persistent duration and rest units remain **seconds**.
 
@@ -313,7 +313,7 @@ The same parser and formatter are reused for:
 
 Invalid malformed forms are rejected before persistence.
 
-## 19. Body screen and measurement graphs — next implementation slice
+## 19. Body screen and measurement graphs — implemented
 
 `F4 Corps` becomes a full history and visualization screen.
 
@@ -388,3 +388,72 @@ Immediate order:
 7. Android recorder and JSON import workflow
 ```
 <!-- TRAINLOG_TUI_V02_CURRENT_AND_NEXT _END -->
+
+<!-- TRAINLOG_GLOBAL_BODY_GRAPH_NEXT -->
+## 21. Global body evolution graph — next implementation slice
+
+`F4 Corps` keeps its current per-metric graph and gains a global normalized
+overlay view.
+
+The global graph must not overlay raw kilograms and centimeters directly.
+
+Each metric is normalized to its own first real observation:
+
+```text
+first recorded value = 100
+```
+
+Examples:
+
+```text
+waist 100 -> 96 = -4 %
+right arm 100 -> 103 = +3 %
+weight 100 -> 98 = -2 %
+```
+
+This makes unlike units visually comparable without changing persisted data.
+
+Rules:
+- no missing observation becomes zero;
+- each metric begins only at its first real value;
+- original dates remain ordered;
+- every series has both a color and a distinct text/symbol identity;
+- left/right limb metrics remain separate;
+- normalization is display-only;
+- canonical SQLite values remain untouched.
+
+The global view is toggled from `F4 Corps` with `g`.
+Per-metric navigation remains left/right.
+
+The global view also shows a compact percentage summary from first to latest
+recorded value for each available metric.
+
+## 22. Dashboard graph v2 — next implementation slice
+
+The dashboard body-weight graph becomes a richer summary.
+
+It will show:
+- current body weight;
+- change from first recorded weight;
+- change from previous recorded weight;
+- minimum recorded weight;
+- maximum recorded weight;
+- recent weight graph;
+- latest waist measurement when available;
+- latest left/right asymmetry alert when meaningful.
+
+The dashboard remains intentionally compact.
+The complete multi-metric overlay belongs to `F4 Corps`.
+
+## 23. Immediate TUI implementation order
+
+```text
+TUI_DURATION_HUMAN_INPUT=IMPLEMENTED
+TUI_BODY_METRIC_GRAPHS=IMPLEMENTED
+TUI_GLOBAL_BODY_OVERLAY=NEXT
+DASHBOARD_GRAPH_V2=NEXT
+EXERCISE_PERFORMANCE_GRAPHS=AFTER
+```
+
+Android remains deferred until these TUI daily-use views are satisfactory.
+<!-- TRAINLOG_GLOBAL_BODY_GRAPH_NEXT _END -->

tui/include/trainlog/database.h

@@ -124,4 +124,52 @@ TrainlogStatus trainlog_database_get_session_details(
     size_t *output_exercise_count
 );
 
+
+/* TRAINLOG_BODY_METRIC_HISTORY_API */
+
+typedef enum TrainlogBodyMetric {
+    TRAINLOG_BODY_METRIC_WEIGHT = 0,
+    TRAINLOG_BODY_METRIC_NECK,
+    TRAINLOG_BODY_METRIC_SHOULDERS,
+    TRAINLOG_BODY_METRIC_CHEST,
+    TRAINLOG_BODY_METRIC_WAIST,
+    TRAINLOG_BODY_METRIC_HIPS,
+    TRAINLOG_BODY_METRIC_LEFT_ARM,
+    TRAINLOG_BODY_METRIC_RIGHT_ARM,
+    TRAINLOG_BODY_METRIC_LEFT_FOREARM,
+    TRAINLOG_BODY_METRIC_RIGHT_FOREARM,
+    TRAINLOG_BODY_METRIC_LEFT_THIGH,
+    TRAINLOG_BODY_METRIC_RIGHT_THIGH,
+    TRAINLOG_BODY_METRIC_LEFT_CALF,
+    TRAINLOG_BODY_METRIC_RIGHT_CALF,
+    TRAINLOG_BODY_METRIC_COUNT
+} TrainlogBodyMetric;
+
+typedef struct TrainlogBodyMetricPoint {
+    char observed_at[TRAINLOG_TIMESTAMP_MAX + 1U];
+    double value;
+} TrainlogBodyMetricPoint;
+
+typedef struct TrainlogBodyPairPoint {
+    bool found;
+    char observed_at[TRAINLOG_TIMESTAMP_MAX + 1U];
+    double left_value;
+    double right_value;
+} TrainlogBodyPairPoint;
+
+TrainlogStatus trainlog_database_list_body_metric_points(
+    TrainlogDatabase *database,
+    TrainlogBodyMetric metric,
+    TrainlogBodyMetricPoint *output,
+    size_t capacity,
+    size_t *output_count
+);
+
+TrainlogStatus trainlog_database_latest_body_pair(
+    TrainlogDatabase *database,
+    TrainlogBodyMetric left_metric,
+    TrainlogBodyMetric right_metric,
+    TrainlogBodyPairPoint *output
+);
+
 #endif

tui/include/trainlog/duration.h

@@ -0,0 +1,24 @@
+#ifndef TRAINLOG_DURATION_H
+#define TRAINLOG_DURATION_H
+
+/**
+ * @file duration.h
+ * @brief Human duration parsing and formatting for Trainlog.
+ */
+
+#include <stddef.h>
+
+#include "trainlog/status.h"
+
+TrainlogStatus trainlog_duration_parse(
+    const char *text,
+    int *output_seconds
+);
+
+TrainlogStatus trainlog_duration_format(
+    int seconds,
+    char *output,
+    size_t output_size
+);
+
+#endif

tui/meson.build

@@ -27,6 +27,7 @@ strict_c_args = [
 trainlog_core_sources = files(
   'src/catalog.c',
   'src/database.c',
+  'src/duration.c',
   'src/id.c',
   'src/timeutil.c',
 )
@@ -107,3 +108,20 @@ test(
   'session_detail',
   test_session_detail,
 )
+
+test_duration = executable(
+  'test_duration',
+  'tests/test_duration.c',
+  dependencies: trainlog_core_dep,
+  c_args: strict_c_args,
+)
+
+test_body_metrics = executable(
+  'test_body_metrics',
+  'tests/test_body_metrics.c',
+  dependencies: trainlog_core_dep,
+  c_args: strict_c_args,
+)
+
+test('duration', test_duration)
+test('body_metrics', test_body_metrics)

tui/src/database.c

@@ -4,6 +4,7 @@
  */
 
 #include "trainlog/database.h"
+#include "trainlog/duration.h"
 
 #include <stdint.h>
 #include <stdio.h>
@@ -1351,20 +1352,31 @@ static TrainlogStatus detail_fill_sets(
         } else if (has_duration != 0) {
             int duration = sqlite3_column_int(statement, 1);
 
+            char duration_text[64];
+
+            if (trainlog_duration_format(
+                    duration,
+                    duration_text,
+                    sizeof(duration_text)
+                ) != TRAINLOG_STATUS_OK) {
+                (void)sqlite3_finalize(statement);
+                return TRAINLOG_STATUS_DATABASE_ERROR;
+            }
+
             if (has_weight != 0) {
                 written = snprintf(
                     fragment,
                     sizeof(fragment),
-                    "%ds@%.1f",
+                    "%s@%.1f",
-                    duration,
+                    duration_text,
                     sqlite3_column_double(statement, 2)
                 );
             } else {
                 written = snprintf(
                     fragment,
                     sizeof(fragment),
-                    "%ds",
+                    "%s",
-                    duration
+                    duration_text
                 );
             }
         } else {
@@ -1661,3 +1673,240 @@ TrainlogStatus trainlog_database_get_session_details(
 
     return TRAINLOG_STATUS_OK;
 }
+
+/* TRAINLOG_BODY_METRIC_HISTORY_IMPLEMENTATION */
+
+static const char *body_metric_column(TrainlogBodyMetric metric)
+{
+    switch (metric) {
+    case TRAINLOG_BODY_METRIC_WEIGHT:
+        return "body_weight_kg";
+    case TRAINLOG_BODY_METRIC_NECK:
+        return "neck_cm";
+    case TRAINLOG_BODY_METRIC_SHOULDERS:
+        return "shoulders_cm";
+    case TRAINLOG_BODY_METRIC_CHEST:
+        return "chest_cm";
+    case TRAINLOG_BODY_METRIC_WAIST:
+        return "waist_cm";
+    case TRAINLOG_BODY_METRIC_HIPS:
+        return "hips_cm";
+    case TRAINLOG_BODY_METRIC_LEFT_ARM:
+        return "left_arm_cm";
+    case TRAINLOG_BODY_METRIC_RIGHT_ARM:
+        return "right_arm_cm";
+    case TRAINLOG_BODY_METRIC_LEFT_FOREARM:
+        return "left_forearm_cm";
+    case TRAINLOG_BODY_METRIC_RIGHT_FOREARM:
+        return "right_forearm_cm";
+    case TRAINLOG_BODY_METRIC_LEFT_THIGH:
+        return "left_thigh_cm";
+    case TRAINLOG_BODY_METRIC_RIGHT_THIGH:
+        return "right_thigh_cm";
+    case TRAINLOG_BODY_METRIC_LEFT_CALF:
+        return "left_calf_cm";
+    case TRAINLOG_BODY_METRIC_RIGHT_CALF:
+        return "right_calf_cm";
+    case TRAINLOG_BODY_METRIC_COUNT:
+    default:
+        return NULL;
+    }
+}
+
+TrainlogStatus trainlog_database_list_body_metric_points(
+    TrainlogDatabase *database,
+    TrainlogBodyMetric metric,
+    TrainlogBodyMetricPoint *output,
+    size_t capacity,
+    size_t *output_count
+)
+{
+    const char *column;
+    char sql[256];
+    sqlite3_stmt *statement = NULL;
+    size_t count = 0U;
+    int written;
+    int rc;
+
+    if (database == NULL ||
+        database->connection == NULL ||
+        output_count == NULL ||
+        (capacity > 0U && output == NULL)) {
+        return TRAINLOG_STATUS_INVALID_ARGUMENT;
+    }
+
+    column = body_metric_column(metric);
+    if (column == NULL) {
+        return TRAINLOG_STATUS_INVALID_ARGUMENT;
+    }
+
+    written = snprintf(
+        sql,
+        sizeof(sql),
+        "SELECT observed_at, %s "
+        "FROM body_observations "
+        "WHERE %s IS NOT NULL "
+        "ORDER BY observed_at ASC, id ASC;",
+        column,
+        column
+    );
+
+    if (written < 0 ||
+        (size_t)written >= sizeof(sql)) {
+        return TRAINLOG_STATUS_SYSTEM_ERROR;
+    }
+
+    rc = sqlite3_prepare_v2(
+        database->connection,
+        sql,
+        -1,
+        &statement,
+        NULL
+    );
+    if (rc != SQLITE_OK) {
+        return TRAINLOG_STATUS_DATABASE_ERROR;
+    }
+
+    while ((rc = sqlite3_step(statement)) == SQLITE_ROW) {
+        if (count < capacity) {
+            const unsigned char *observed =
+                sqlite3_column_text(statement, 0);
+
+            if (observed == NULL) {
+                (void)sqlite3_finalize(statement);
+                return TRAINLOG_STATUS_DATABASE_ERROR;
+            }
+
+            (void)snprintf(
+                output[count].observed_at,
+                sizeof(output[count].observed_at),
+                "%s",
+                (const char *)observed
+            );
+
+            output[count].value =
+                sqlite3_column_double(statement, 1);
+        }
+
+        ++count;
+    }
+
+    if (rc != SQLITE_DONE) {
+        (void)sqlite3_finalize(statement);
+        return TRAINLOG_STATUS_DATABASE_ERROR;
+    }
+
+    if (sqlite3_finalize(statement) != SQLITE_OK) {
+        return TRAINLOG_STATUS_DATABASE_ERROR;
+    }
+
+    *output_count =
+        count < capacity
+            ? count
+            : capacity;
+
+    return TRAINLOG_STATUS_OK;
+}
+
+TrainlogStatus trainlog_database_latest_body_pair(
+    TrainlogDatabase *database,
+    TrainlogBodyMetric left_metric,
+    TrainlogBodyMetric right_metric,
+    TrainlogBodyPairPoint *output
+)
+{
+    const char *left_column;
+    const char *right_column;
+    char sql[384];
+    sqlite3_stmt *statement = NULL;
+    int written;
+    int rc;
+
+    if (database == NULL ||
+        database->connection == NULL ||
+        output == NULL) {
+        return TRAINLOG_STATUS_INVALID_ARGUMENT;
+    }
+
+    left_column = body_metric_column(left_metric);
+    right_column = body_metric_column(right_metric);
+
+    if (left_column == NULL ||
+        right_column == NULL) {
+        return TRAINLOG_STATUS_INVALID_ARGUMENT;
+    }
+
+    (void)memset(output, 0, sizeof(*output));
+
+    written = snprintf(
+        sql,
+        sizeof(sql),
+        "SELECT observed_at, %s, %s "
+        "FROM body_observations "
+        "WHERE %s IS NOT NULL AND %s IS NOT NULL "
+        "ORDER BY observed_at DESC, id DESC "
+        "LIMIT 1;",
+        left_column,
+        right_column,
+        left_column,
+        right_column
+    );
+
+    if (written < 0 ||
+        (size_t)written >= sizeof(sql)) {
+        return TRAINLOG_STATUS_SYSTEM_ERROR;
+    }
+
+    rc = sqlite3_prepare_v2(
+        database->connection,
+        sql,
+        -1,
+        &statement,
+        NULL
+    );
+    if (rc != SQLITE_OK) {
+        return TRAINLOG_STATUS_DATABASE_ERROR;
+    }
+
+    rc = sqlite3_step(statement);
+
+    if (rc == SQLITE_DONE) {
+        (void)sqlite3_finalize(statement);
+        output->found = false;
+        return TRAINLOG_STATUS_OK;
+    }
+
+    if (rc != SQLITE_ROW) {
+        (void)sqlite3_finalize(statement);
+        return TRAINLOG_STATUS_DATABASE_ERROR;
+    }
+
+    {
+        const unsigned char *observed =
+            sqlite3_column_text(statement, 0);
+
+        if (observed == NULL) {
+            (void)sqlite3_finalize(statement);
+            return TRAINLOG_STATUS_DATABASE_ERROR;
+        }
+
+        output->found = true;
+
+        (void)snprintf(
+            output->observed_at,
+            sizeof(output->observed_at),
+            "%s",
+            (const char *)observed
+        );
+
+        output->left_value =
+            sqlite3_column_double(statement, 1);
+
+        output->right_value =
+            sqlite3_column_double(statement, 2);
+    }
+
+    return sqlite3_finalize(statement) == SQLITE_OK
+        ? TRAINLOG_STATUS_OK
+        : TRAINLOG_STATUS_DATABASE_ERROR;
+}

tui/src/duration.c

@@ -0,0 +1,270 @@
+/**
+ * @file duration.c
+ * @brief Human duration parser/formatter implementation.
+ */
+
+#include "trainlog/duration.h"
+
+#include <limits.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <string.h>
+
+static bool ascii_space(char value)
+{
+    return value == ' ' ||
+           value == '\t' ||
+           value == '\n' ||
+           value == '\r' ||
+           value == '\f' ||
+           value == '\v';
+}
+
+static bool ascii_digit(char value)
+{
+    return value >= '0' && value <= '9';
+}
+
+static bool parse_decimal_range(
+    const char *begin,
+    const char *end,
+    int *output
+)
+{
+    long long value = 0;
+    const char *cursor;
+
+    if (begin == NULL ||
+        end == NULL ||
+        output == NULL ||
+        begin >= end) {
+        return false;
+    }
+
+    for (cursor = begin; cursor < end; ++cursor) {
+        int digit;
+
+        if (!ascii_digit(*cursor)) {
+            return false;
+        }
+
+        digit = *cursor - '0';
+
+        if (value > ((long long)INT_MAX - digit) / 10LL) {
+            return false;
+        }
+
+        value = (value * 10LL) + digit;
+    }
+
+    *output = (int)value;
+    return true;
+}
+
+static bool checked_minutes_seconds(
+    int minutes,
+    int seconds,
+    int *output
+)
+{
+    long long total;
+
+    if (minutes < 0 ||
+        seconds < 0 ||
+        seconds >= 60 ||
+        output == NULL) {
+        return false;
+    }
+
+    total = ((long long)minutes * 60LL) + seconds;
+
+    if (total > (long long)INT_MAX) {
+        return false;
+    }
+
+    *output = (int)total;
+    return true;
+}
+
+TrainlogStatus trainlog_duration_parse(
+    const char *text,
+    int *output_seconds
+)
+{
+    const char *begin;
+    const char *end;
+    const char *cursor;
+    const char *colon = NULL;
+    const char *minute_marker = NULL;
+    int value;
+
+    if (text == NULL || output_seconds == NULL) {
+        return TRAINLOG_STATUS_INVALID_ARGUMENT;
+    }
+
+    begin = text;
+    while (*begin != '\0' && ascii_space(*begin)) {
+        ++begin;
+    }
+
+    end = text + strlen(text);
+    while (end > begin && ascii_space(end[-1])) {
+        --end;
+    }
+
+    if (begin == end ||
+        (size_t)(end - begin) > 63U) {
+        return TRAINLOG_STATUS_INVALID_ARGUMENT;
+    }
+
+    for (cursor = begin; cursor < end; ++cursor) {
+        if (ascii_space(*cursor)) {
+            return TRAINLOG_STATUS_INVALID_ARGUMENT;
+        }
+
+        if (*cursor == ':') {
+            if (colon != NULL) {
+                return TRAINLOG_STATUS_INVALID_ARGUMENT;
+            }
+            colon = cursor;
+        }
+
+        if (*cursor == 'm' || *cursor == 'M') {
+            if (minute_marker != NULL) {
+                return TRAINLOG_STATUS_INVALID_ARGUMENT;
+            }
+            minute_marker = cursor;
+        }
+    }
+
+    if (colon != NULL) {
+        int minutes;
+        int seconds;
+
+        if (minute_marker != NULL ||
+            !parse_decimal_range(begin, colon, &minutes) ||
+            !parse_decimal_range(colon + 1, end, &seconds) ||
+            !checked_minutes_seconds(
+                minutes,
+                seconds,
+                output_seconds
+            )) {
+            return TRAINLOG_STATUS_INVALID_ARGUMENT;
+        }
+
+        return TRAINLOG_STATUS_OK;
+    }
+
+    if (minute_marker != NULL) {
+        int minutes;
+        int seconds = 0;
+        const char *seconds_begin = minute_marker + 1;
+        const char *seconds_end = end;
+
+        if (!parse_decimal_range(
+                begin,
+                minute_marker,
+                &minutes
+            )) {
+            return TRAINLOG_STATUS_INVALID_ARGUMENT;
+        }
+
+        if (seconds_begin < end &&
+            (end[-1] == 's' || end[-1] == 'S')) {
+            seconds_end = end - 1;
+        }
+
+        if (seconds_begin < seconds_end) {
+            if (!parse_decimal_range(
+                    seconds_begin,
+                    seconds_end,
+                    &seconds
+                )) {
+                return TRAINLOG_STATUS_INVALID_ARGUMENT;
+            }
+        } else if (seconds_begin < end) {
+            return TRAINLOG_STATUS_INVALID_ARGUMENT;
+        }
+
+        if (!checked_minutes_seconds(
+                minutes,
+                seconds,
+                output_seconds
+            )) {
+            return TRAINLOG_STATUS_INVALID_ARGUMENT;
+        }
+
+        return TRAINLOG_STATUS_OK;
+    }
+
+    if (end[-1] == 's' || end[-1] == 'S') {
+        if (!parse_decimal_range(
+                begin,
+                end - 1,
+                &value
+            )) {
+            return TRAINLOG_STATUS_INVALID_ARGUMENT;
+        }
+
+        *output_seconds = value;
+        return TRAINLOG_STATUS_OK;
+    }
+
+    if (!parse_decimal_range(begin, end, &value)) {
+        return TRAINLOG_STATUS_INVALID_ARGUMENT;
+    }
+
+    *output_seconds = value;
+    return TRAINLOG_STATUS_OK;
+}
+
+TrainlogStatus trainlog_duration_format(
+    int seconds,
+    char *output,
+    size_t output_size
+)
+{
+    int minutes;
+    int remainder;
+    int written;
+
+    if (seconds < 0 ||
+        output == NULL ||
+        output_size == 0U) {
+        return TRAINLOG_STATUS_INVALID_ARGUMENT;
+    }
+
+    minutes = seconds / 60;
+    remainder = seconds % 60;
+
+    if (minutes == 0) {
+        written = snprintf(
+            output,
+            output_size,
+            "%d s",
+            remainder
+        );
+    } else if (remainder == 0) {
+        written = snprintf(
+            output,
+            output_size,
+            "%d min",
+            minutes
+        );
+    } else {
+        written = snprintf(
+            output,
+            output_size,
+            "%d min %d s",
+            minutes,
+            remainder
+        );
+    }
+
+    if (written < 0 ||
+        (size_t)written >= output_size) {
+        return TRAINLOG_STATUS_SYSTEM_ERROR;
+    }
+
+    return TRAINLOG_STATUS_OK;
+}

tui/tests/test_body_metrics.c

@@ -0,0 +1,104 @@
+/**
+ * @file test_body_metrics.c
+ * @brief Generic body-metric history tests.
+ */
+
+#include <stdbool.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "trainlog/database.h"
+
+#define CHECK(condition)                                                     \
+    do {                                                                     \
+        if (!(condition)) {                                                  \
+            (void)fprintf(stderr, "CHECK failed at %s:%d: %s\n",             \
+                __FILE__, __LINE__, #condition);                             \
+            return false;                                                    \
+        }                                                                    \
+    } while (0)
+
+static bool test_body_metrics(void)
+{
+    TrainlogDatabase *database = NULL;
+    TrainlogBodyObservationInput observation;
+    TrainlogBodyMetricPoint points[8];
+    TrainlogBodyPairPoint pair;
+    size_t count = 0U;
+
+    CHECK(
+        trainlog_database_open(":memory:", &database) ==
+        TRAINLOG_STATUS_OK
+    );
+
+    (void)memset(&observation, 0, sizeof(observation));
+
+    (void)snprintf(
+        observation.observation_id,
+        sizeof(observation.observation_id),
+        "%s",
+        "bo_metrics"
+    );
+
+    (void)snprintf(
+        observation.observed_at,
+        sizeof(observation.observed_at),
+        "%s",
+        "2026-09-05T08:00:00+02:00"
+    );
+
+    observation.has_body_weight = true;
+    observation.body_weight_kg = 84.1;
+    observation.has_waist = true;
+    observation.waist_cm = 96.4;
+    observation.has_left_arm = true;
+    observation.left_arm_cm = 34.2;
+    observation.has_right_arm = true;
+    observation.right_arm_cm = 34.8;
+
+    CHECK(
+        trainlog_database_insert_body_observation(
+            database,
+            &observation
+        ) == TRAINLOG_STATUS_OK
+    );
+
+    CHECK(
+        trainlog_database_list_body_metric_points(
+            database,
+            TRAINLOG_BODY_METRIC_WAIST,
+            points,
+            8U,
+            &count
+        ) == TRAINLOG_STATUS_OK
+    );
+
+    CHECK(count == 1U);
+    CHECK(points[0].value > 96.39);
+    CHECK(points[0].value < 96.41);
+
+    CHECK(
+        trainlog_database_latest_body_pair(
+            database,
+            TRAINLOG_BODY_METRIC_LEFT_ARM,
+            TRAINLOG_BODY_METRIC_RIGHT_ARM,
+            &pair
+        ) == TRAINLOG_STATUS_OK
+    );
+
+    CHECK(pair.found);
+    CHECK(pair.left_value > 34.19);
+    CHECK(pair.left_value < 34.21);
+    CHECK(pair.right_value > 34.79);
+    CHECK(pair.right_value < 34.81);
+
+    trainlog_database_close(database);
+    return true;
+}
+
+int main(void)
+{
+    CHECK(test_body_metrics());
+    (void)printf("PASS body_metrics\n");
+    return 0;
+}

tui/tests/test_duration.c

@@ -0,0 +1,112 @@
+/**
+ * @file test_duration.c
+ * @brief Human duration parser/formatter tests.
+ */
+
+#include <stdbool.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "trainlog/duration.h"
+
+#define CHECK(condition)                                                     \
+    do {                                                                     \
+        if (!(condition)) {                                                  \
+            (void)fprintf(                                                   \
+                stderr,                                                      \
+                "CHECK failed at %s:%d: %s\n",                               \
+                __FILE__,                                                    \
+                __LINE__,                                                    \
+                #condition                                                   \
+            );                                                               \
+            return false;                                                    \
+        }                                                                    \
+    } while (0)
+
+static bool expect_parse(const char *text, int expected)
+{
+    int seconds = -1;
+
+    CHECK(
+        trainlog_duration_parse(text, &seconds) ==
+        TRAINLOG_STATUS_OK
+    );
+    CHECK(seconds == expected);
+    return true;
+}
+
+static bool test_parsing(void)
+{
+    int scratch = 0;
+
+    CHECK(expect_parse("90", 90));
+    CHECK(expect_parse("90s", 90));
+    CHECK(expect_parse("1:30", 90));
+    CHECK(expect_parse("1m30", 90));
+    CHECK(expect_parse("1m30s", 90));
+    CHECK(expect_parse("2m", 120));
+    CHECK(expect_parse("45s", 45));
+    CHECK(expect_parse("2:05", 125));
+    CHECK(expect_parse("  2m  ", 120));
+
+    CHECK(
+        trainlog_duration_parse("1:60", &scratch) ==
+        TRAINLOG_STATUS_INVALID_ARGUMENT
+    );
+    CHECK(
+        trainlog_duration_parse("1m90", &scratch) ==
+        TRAINLOG_STATUS_INVALID_ARGUMENT
+    );
+    CHECK(
+        trainlog_duration_parse("1 m 30", &scratch) ==
+        TRAINLOG_STATUS_INVALID_ARGUMENT
+    );
+    CHECK(
+        trainlog_duration_parse("", &scratch) ==
+        TRAINLOG_STATUS_INVALID_ARGUMENT
+    );
+
+    return true;
+}
+
+static bool test_formatting(void)
+{
+    char buffer[64];
+
+    CHECK(
+        trainlog_duration_format(45, buffer, sizeof(buffer)) ==
+        TRAINLOG_STATUS_OK
+    );
+    CHECK(strcmp(buffer, "45 s") == 0);
+
+    CHECK(
+        trainlog_duration_format(60, buffer, sizeof(buffer)) ==
+        TRAINLOG_STATUS_OK
+    );
+    CHECK(strcmp(buffer, "1 min") == 0);
+
+    CHECK(
+        trainlog_duration_format(90, buffer, sizeof(buffer)) ==
+        TRAINLOG_STATUS_OK
+    );
+    CHECK(strcmp(buffer, "1 min 30 s") == 0);
+
+    CHECK(
+        trainlog_duration_format(125, buffer, sizeof(buffer)) ==
+        TRAINLOG_STATUS_OK
+    );
+    CHECK(strcmp(buffer, "2 min 5 s") == 0);
+
+    return true;
+}
+
+int main(void)
+{
+    CHECK(test_parsing());
+    (void)printf("PASS duration_parsing\n");
+
+    CHECK(test_formatting());
+    (void)printf("PASS duration_formatting\n");
+
+    return 0;
+}