#include "../../unity/unity.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

/* Helpers to build and free minimal struct line objects for prjoin. */
static struct line *T_make_line(const char **fields, size_t n)
{
    struct line *l = (struct line *)calloc(1, sizeof(*l));
    TEST_ASSERT_NOT_NULL_MESSAGE(l, "alloc line");
    l->nfields = (idx_t)n;
    l->nfields_allocated = (idx_t)n;
    if (n) {
        l->fields = (struct field *)calloc(n, sizeof(struct field));
        TEST_ASSERT_NOT_NULL_MESSAGE(l->fields, "alloc fields");
        for (size_t i = 0; i < n; ++i) {
            size_t len = strlen(fields[i]);
            char *s = (char *)malloc(len + 1);
            TEST_ASSERT_NOT_NULL_MESSAGE(s, "alloc field string");
            memcpy(s, fields[i], len + 1);
            l->fields[i].beg = s;
            l->fields[i].len = (idx_t)len;
        }
    }
    return l;
}

static void T_free_line(struct line *l)
{
    if (!l) return;
    for (size_t i = 0; i < (size_t)l->nfields; ++i) {
        free(l->fields[i].beg);
    }
    free(l->fields);
    free(l);
}

/* Reset and free the global outlist. */
static void T_reset_outlist(void)
{
    struct outlist *o = outlist_head.next;
    while (o) {
        struct outlist *next = o->next;
        free(o);
        o = next;
    }
    outlist_head.next = NULL;
    outlist_end = &outlist_head;
}

/* Capture stdout while invoking prjoin. Do not use Unity asserts while stdout is redirected. */
typedef struct { char *data; size_t len; } TCap;
static TCap T_capture_prjoin(const struct line *l1, const struct line *l2)
{
    TCap r = {0, 0};
    fflush(stdout);

    int saved_fd = dup(fileno(stdout));
    FILE *tmp = tmpfile();
    if (!tmp || saved_fd < 0) {
        if (tmp) fclose(tmp);
        return r;
    }

    int tmp_fd = fileno(tmp);
    fflush(stdout);
    dup2(tmp_fd, fileno(stdout));

    /* Call the function under test. */
    prjoin(l1, l2);

    fflush(stdout);
    long pos = ftell(tmp);
    if (pos < 0) pos = 0;
    r.len = (size_t)pos;
    r.data = (char *)malloc(r.len + 1);
    if (r.data) {
        memset(r.data, 0, r.len + 1);
        rewind(tmp);
        fread(r.data, 1, r.len, tmp);
    }

    fflush(stdout);
    dup2(saved_fd, fileno(stdout));
    close(saved_fd);
    fclose(tmp);

    return r;
}

static void T_free_cap(TCap *c)
{
    if (!c) return;
    free(c->data);
    c->data = NULL;
    c->len = 0;
}

/* Save/restore selected globals around tests. */
static const char *saved_output_separator;
static idx_t saved_output_seplen;
static char saved_eolchar;
static const char *saved_empty_filler;
static ptrdiff_t saved_join_field_1;
static ptrdiff_t saved_join_field_2;
static bool saved_autoformat;
static idx_t saved_autocount_1;
static idx_t saved_autocount_2;

void setUp(void)
{
    /* Save state */
    saved_output_separator = output_separator;
    saved_output_seplen = output_seplen;
    saved_eolchar = eolchar;
    saved_empty_filler = empty_filler;
    saved_join_field_1 = join_field_1;
    saved_join_field_2 = join_field_2;
    saved_autoformat = autoformat;
    saved_autocount_1 = autocount_1;
    saved_autocount_2 = autocount_2;

    /* Start with a clean outlist for each test. */
    T_reset_outlist();

    /* Default common settings */
    output_separator = " ";
    output_seplen = 1;
    eolchar = '\n';
    empty_filler = NULL;
    join_field_1 = 0;
    join_field_2 = 0;
    autoformat = false;
    autocount_1 = 0;
    autocount_2 = 0;
}

void tearDown(void)
{
    /* Clean any remaining outlist nodes and restore saved state. */
    T_reset_outlist();

    output_separator = saved_output_separator;
    output_seplen = saved_output_seplen;
    eolchar = saved_eolchar;
    empty_filler = saved_empty_filler;
    join_field_1 = saved_join_field_1;
    join_field_2 = saved_join_field_2;
    autoformat = saved_autoformat;
    autocount_1 = saved_autocount_1;
    autocount_2 = saved_autocount_2;
}

/* Test 1: Default format, both lines present. */
static void test_prjoin_default_basic(void)
{
    const char *f1[] = {"join", "a", "b"};
    const char *f2[] = {"join", "c"};
    struct line *l1 = T_make_line(f1, 3);
    struct line *l2 = T_make_line(f2, 2);

    /* Defaults already set in setUp: space separator, '\n', join field 0 */
    TCap cap = T_capture_prjoin(l1, l2);

    TEST_ASSERT_NOT_NULL(cap.data);
    TEST_ASSERT_EQUAL_STRING("join a b c\n", cap.data);

    T_free_cap(&cap);
    T_free_line(l1);
    T_free_line(l2);
}

/* Test 2: Default format, first line is uni_blank so join field is taken from second line. */
static void test_prjoin_default_blank_first(void)
{
    const char *f2[] = {"K", "x"};
    struct line *l2 = T_make_line(f2, 2);

    /* join_field_2 = 0 already; expect: K x\n */
    TCap cap = T_capture_prjoin(&uni_blank, l2);

    TEST_ASSERT_NOT_NULL(cap.data);
    TEST_ASSERT_EQUAL_STRING("K x\n", cap.data);

    T_free_cap(&cap);
    T_free_line(l2);
}

/* Test 3: Custom outlist ordering, including '0' (join field), with custom separator. */
static void test_prjoin_outlist_custom_order_and_separator(void)
{
    const char *f1[] = {"J", "A", "B"};
    const char *f2[] = {"X", "C"};
    struct line *l1 = T_make_line(f1, 3);
    struct line *l2 = T_make_line(f2, 2);

    output_separator = ",";
    output_seplen = 1;
    join_field_1 = 0; /* '0' should print J from l1 */

    char spec[] = "1.3,0,2.2,1.2"; /* B,J,C,A */
    add_field_list(spec);

    TCap cap = T_capture_prjoin(l1, l2);

    TEST_ASSERT_NOT_NULL(cap.data);
    TEST_ASSERT_EQUAL_STRING("B,J,C,A\n", cap.data);

    T_free_cap(&cap);
    T_free_line(l1);
    T_free_line(l2);
}

/* Test 4: Custom outlist with missing and empty fields, using empty_filler and custom separator. */
static void test_prjoin_outlist_missing_and_empty_filler(void)
{
    const char *f1[] = {"J"};
    const char *f2[] = {"J", ""};
    struct line *l1 = T_make_line(f1, 1);
    struct line *l2 = T_make_line(f2, 2);

    empty_filler = "<EMPTY>";
    output_separator = "|";
    output_seplen = 1;

    char spec[] = "1.2,2.2,2.3"; /* missing in l1, empty in l2, missing in l2 */
    add_field_list(spec);

    TCap cap = T_capture_prjoin(l1, l2);

    TEST_ASSERT_NOT_NULL(cap.data);
    TEST_ASSERT_EQUAL_STRING("<EMPTY>|<EMPTY>|<EMPTY>\n", cap.data);

    T_free_cap(&cap);
    T_free_line(l1);
    T_free_line(l2);
}

/* Test 5: Default format with autoformat limiting the number of fields printed from each line. */
static void test_prjoin_autoformat_limits(void)
{
    const char *f1[] = {"J", "A", "B"};
    const char *f2[] = {"J", "C", "D", "E"};
    struct line *l1 = T_make_line(f1, 3);
    struct line *l2 = T_make_line(f2, 4);

    autoformat = true;
    autocount_1 = 1; /* Only 1 field (index 0) available from line1 */
    autocount_2 = 2; /* Two fields total in line2 => only field 1 gets printed */
    join_field_1 = 0;
    join_field_2 = 0;

    TCap cap = T_capture_prjoin(l1, l2);

    TEST_ASSERT_NOT_NULL(cap.data);
    TEST_ASSERT_EQUAL_STRING("J C\n", cap.data);

    T_free_cap(&cap);
    T_free_line(l1);
    T_free_line(l2);
}

/* Test 6: Zero-terminated records and non-space separator; verify bytes including NUL. */
static void test_prjoin_zero_terminated_eol(void)
{
    const char *f1[] = {"K"};
    const char *f2[] = {"K", "X"};
    struct line *l1 = T_make_line(f1, 1);
    struct line *l2 = T_make_line(f2, 2);

    eolchar = '\0';
    output_separator = "=";
    output_seplen = 1;
    join_field_1 = 0;
    join_field_2 = 0;

    TCap cap = T_capture_prjoin(l1, l2);

    TEST_ASSERT_NOT_NULL(cap.data);
    TEST_ASSERT_EQUAL_UINT32(4, (uint32_t)cap.len);
    const char expected[4] = {'K', '=', 'X', '\0'};
    TEST_ASSERT_EQUAL_INT(0, memcmp(expected, cap.data, 4));

    T_free_cap(&cap);
    T_free_line(l1);
    T_free_line(l2);
}

int main(void)
{
    UNITY_BEGIN();
    RUN_TEST(test_prjoin_default_basic);
    RUN_TEST(test_prjoin_default_blank_first);
    RUN_TEST(test_prjoin_outlist_custom_order_and_separator);
    RUN_TEST(test_prjoin_outlist_missing_and_empty_filler);
    RUN_TEST(test_prjoin_autoformat_limits);
    RUN_TEST(test_prjoin_zero_terminated_eol);
    return UNITY_END();
}