#define DISABLE_SIGN_COMPARE_WARNINGS

#include "git-compat-util.h"

#include "config.h"

#include "column.h"

#include "string-list.h"

#include "pager.h"

#include "parse-options.h"

#include "run-command.h"

#include "utf8.h"

#define XY2LINEAR(d, x, y) (COL_LAYOUT((d)->colopts) == COL_COLUMN ? \

          (x) * (d)->rows + (y) : \

          (y) * (d)->cols + (x))

struct column_data {

  const struct string_list *list;

  unsigned int colopts;

  struct column_options opts;

  int rows, cols;

  int *len;   /* cell length */

  int *width;       /* index to the longest row in column */

};

/* return length of 's' in letters, ANSI escapes stripped */

static int item_length(const char *s)

{

  return utf8_strnwidth(s, strlen(s), 1);

}

/*

 * Calculate cell width, rows and cols for a table of equal cells, given

 * table width and how many spaces between cells.

 */

static void layout(struct column_data *data, int *width)

{

  int i;

  *width = 0;

  for (i = 0; i < data->list->nr; i++)

    if (*width < data->len[i])

      *width = data->len[i];

  *width += data->opts.padding;

  data->cols = (data->opts.width - strlen(data->opts.indent)) / *width;

  if (data->cols == 0)

    data->cols = 1;

  data->rows = DIV_ROUND_UP(data->list->nr, data->cols);

}

static void compute_column_width(struct column_data *data)

{

  int i, x, y;

  for (x = 0; x < data->cols; x++) {

    data->width[x] = XY2LINEAR(data, x, 0);

    for (y = 0; y < data->rows; y++) {

      i = XY2LINEAR(data, x, y);

      if (i < data->list->nr &&

          data->len[data->width[x]] < data->len[i])

        data->width[x] = i;

    }

  }

}

/*

 * Shrink all columns by shortening them one row each time (and adding

 * more columns along the way). Hopefully the longest cell will be

 * moved to the next column, column is shrunk so we have more space

 * for new columns. The process ends when the whole thing no longer

 * fits in data->total_width.

 */

static void shrink_columns(struct column_data *data)

{

  REALLOC_ARRAY(data->width, data->cols);

  while (data->rows > 1) {

    int x, total_width, cols, rows;

    rows = data->rows;

    cols = data->cols;

    data->rows--;

    data->cols = DIV_ROUND_UP(data->list->nr, data->rows);

    if (data->cols != cols)

      REALLOC_ARRAY(data->width, data->cols);

    compute_column_width(data);

    total_width = strlen(data->opts.indent);

    for (x = 0; x < data->cols; x++) {

      total_width += data->len[data->width[x]];

      total_width += data->opts.padding;

    }

    if (total_width > data->opts.width) {

      data->rows = rows;

      data->cols = cols;

      break;

    }

  }

  compute_column_width(data);

}

/* Display without layout when not enabled */

static void display_plain(const struct string_list *list,

        const char *indent, const char *nl)

{

  int i;

  for (i = 0; i < list->nr; i++)

    printf("%s%s%s", indent, list->items[i].string, nl);

}

/* Print a cell to stdout with all necessary leading/trailing space */

static int display_cell(struct column_data *data, int initial_width,

      const char *empty_cell, int x, int y)

{

  int i, len, newline;

  i = XY2LINEAR(data, x, y);

  if (i >= data->list->nr)

    return -1;

  len = data->len[i];

  if (data->width && data->len[data->width[x]] < initial_width) {

    /*

     * empty_cell has initial_width chars, if real column

     * is narrower, increase len a bit so we fill less

     * space.

     */

    len += initial_width - data->len[data->width[x]];

    len -= data->opts.padding;

  }

  if (COL_LAYOUT(data->colopts) == COL_COLUMN)

    newline = i + data->rows >= data->list->nr;

  else

    newline = x == data->cols - 1 || i == data->list->nr - 1;

  printf("%s%s%s",

         x == 0 ? data->opts.indent : "",

         data->list->items[i].string,

         newline ? data->opts.nl : empty_cell + len);

  return 0;

}

/* Display COL_COLUMN or COL_ROW */

static void display_table(const struct string_list *list,

        unsigned int colopts,

        const struct column_options *opts)

{

  struct column_data data;

  int x, y, i, initial_width;

  char *empty_cell;

  memset(&data, 0, sizeof(data));

  data.list = list;

  data.colopts = colopts;

  data.opts = *opts;

  ALLOC_ARRAY(data.len, list->nr);

  for (i = 0; i < list->nr; i++)

    data.len[i] = item_length(list->items[i].string);

  layout(&data, &initial_width);

  if (colopts & COL_DENSE)

    shrink_columns(&data);

  empty_cell = xmallocz(initial_width);

  memset(empty_cell, ' ', initial_width);

  for (y = 0; y < data.rows; y++) {

    for (x = 0; x < data.cols; x++)

      if (display_cell(&data, initial_width, empty_cell, x, y))

        break;

  }

  free(data.len);

  free(data.width);

  free(empty_cell);

}

void print_columns(const struct string_list *list, unsigned int colopts,

       const struct column_options *opts)

{

  struct column_options nopts;

  if (opts && (0 > opts->padding))

    BUG("padding must be non-negative");

  if (!list->nr)

    return;

  assert((colopts & COL_ENABLE_MASK) != COL_AUTO);

  memset(&nopts, 0, sizeof(nopts));

  nopts.indent = opts && opts->indent ? opts->indent : "";

  nopts.nl = opts && opts->nl ? opts->nl : "\n";

  nopts.padding = opts ? opts->padding : 1;

  nopts.width = opts && opts->width ? opts->width : term_columns() - 1;

  if (!column_active(colopts)) {

    display_plain(list, "", "\n");

    return;

  }

  switch (COL_LAYOUT(colopts)) {

  case COL_PLAIN:

    display_plain(list, nopts.indent, nopts.nl);

    break;

  case COL_ROW:

  case COL_COLUMN:

    display_table(list, colopts, &nopts);

    break;

  default:

    BUG("invalid layout mode %d", COL_LAYOUT(colopts));

  }

}

int finalize_colopts(unsigned int *colopts, int stdout_is_tty)

{

  if ((*colopts & COL_ENABLE_MASK) == COL_AUTO) {

    if (stdout_is_tty < 0)

      stdout_is_tty = isatty(1);

    *colopts &= ~COL_ENABLE_MASK;

    if (stdout_is_tty || pager_in_use())

      *colopts |= COL_ENABLED;

  }

  return 0;

}

struct colopt {

  const char *name;

  unsigned int value;

  unsigned int mask;

};

#define LAYOUT_SET 1

#define ENABLE_SET 2

static int parse_option(const char *arg, int len, unsigned int *colopts,

      int *group_set)

{

  struct colopt opts[] = {

    { "always", COL_ENABLED,  COL_ENABLE_MASK },

    { "never",  COL_DISABLED, COL_ENABLE_MASK },

    { "auto",   COL_AUTO,     COL_ENABLE_MASK },

    { "plain",  COL_PLAIN,    COL_LAYOUT_MASK },

    { "column", COL_COLUMN,   COL_LAYOUT_MASK },

    { "row",    COL_ROW,      COL_LAYOUT_MASK },

    { "dense",  COL_DENSE,    0 },

  };

  int i;

  for (i = 0; i < ARRAY_SIZE(opts); i++) {

    int set = 1, arg_len = len, name_len;

    const char *arg_str = arg;

    if (!opts[i].mask) {

      if (arg_len > 2 && !strncmp(arg_str, "no", 2)) {

        arg_str += 2;

        arg_len -= 2;

        set = 0;

      }

    }

    name_len = strlen(opts[i].name);

    if (arg_len != name_len ||

        strncmp(arg_str, opts[i].name, name_len))

      continue;

    switch (opts[i].mask) {

    case COL_ENABLE_MASK:

      *group_set |= ENABLE_SET;

      break;

    case COL_LAYOUT_MASK:

      *group_set |= LAYOUT_SET;

      break;

    }

    if (opts[i].mask)

      *colopts = (*colopts & ~opts[i].mask) | opts[i].value;

    else {

      if (set)

        *colopts |= opts[i].value;

      else

        *colopts &= ~opts[i].value;

    }

    return 0;

  }

  return error("unsupported option '%s'", arg);

}

static int parse_config(unsigned int *colopts, const char *value)

{

  const char *sep = " ,";

  int group_set = 0;

  while (*value) {

    int len = strcspn(value, sep);

    if (len) {

      if (parse_option(value, len, colopts, &group_set))

        return -1;

      value += len;

    }

    value += strspn(value, sep);

  }

  /*

   * If none of "always", "never", and "auto" is specified, then setting

   * layout implies "always".

   *

   * Current value in COL_ENABLE_MASK is disregarded. This means if

   * you set column.ui = auto and pass --column=row, then "auto"

   * will become "always".

   */

  if ((group_set & LAYOUT_SET) && !(group_set & ENABLE_SET))

    *colopts = (*colopts & ~COL_ENABLE_MASK) | COL_ENABLED;

  return 0;

}

static int column_config(const char *var, const char *value,

       const char *key, unsigned int *colopts)

{

  if (!value)

    return config_error_nonbool(var);

  if (parse_config(colopts, value))

    return error("invalid column.%s mode %s", key, value);

  return 0;

}

int git_column_config(const char *var, const char *value,

          const char *command, unsigned int *colopts)

{

  const char *it;

  if (!skip_prefix(var, "column.", &it))

    return 0;

  if (!strcmp(it, "ui"))

    return column_config(var, value, "ui", colopts);

  if (command && !strcmp(it, command))

    return column_config(var, value, it, colopts);

  return 0;

}

int parseopt_column_callback(const struct option *opt,

           const char *arg, int unset)

{

  unsigned int *colopts = opt->value;

  *colopts |= COL_PARSEOPT;

  *colopts &= ~COL_ENABLE_MASK;

  if (unset)   /* --no-column == never */

    return 0;

  /* --column == always unless "arg" states otherwise */

  *colopts |= COL_ENABLED;

  if (arg)

    return parse_config(colopts, arg);

  return 0;

}

static int fd_out = -1;

static struct child_process column_process = CHILD_PROCESS_INIT;

int run_column_filter(int colopts, const struct column_options *opts)

{

  struct strvec *argv;

  if (opts && (0 > opts->padding))

    BUG("padding must be non-negative");

  if (fd_out != -1)

    return -1;

  child_process_init(&column_process);

  argv = &column_process.args;

  strvec_push(argv, "column");

  strvec_pushf(argv, "--raw-mode=%d", colopts);

  if (opts && opts->width)

    strvec_pushf(argv, "--width=%d", opts->width);

  if (opts && opts->indent)

    strvec_pushf(argv, "--indent=%s", opts->indent);

  if (opts && opts->padding)

    strvec_pushf(argv, "--padding=%d", opts->padding);

  fflush(stdout);

  column_process.in = -1;

  column_process.out = dup(1);

  column_process.git_cmd = 1;

  if (start_command(&column_process))

    return -2;

  fd_out = dup(1);

  close(1);

  dup2(column_process.in, 1);

  close(column_process.in);

  return 0;

}

int stop_column_filter(void)

{

  if (fd_out == -1)

    return -1;

  fflush(stdout);

  close(1);

  finish_command(&column_process);

  dup2(fd_out, 1);

  close(fd_out);

  fd_out = -1;

  return 0;

}