#include "cache.h"
#include "color.h"

#define COLOR_RESET "\033[m"

int git_use_color_default = 0;

static int parse_color(const char *name, int len)
{
        static const char * const color_names[] = {
                "normal", "black", "red", "green", "yellow",
                "blue", "magenta", "cyan", "white"
        };
        char *end;
        int i;
        for (i = 0; i < ARRAY_SIZE(color_names); i++) {
                const char *str = color_names[i];
                if (!strncasecmp(name, str, len) && !str[len])
                        return i - 1;
        }
        i = strtol(name, &end, 10);
        if (end - name == len && i >= -1 && i <= 255)
                return i;
        return -2;
}

static int parse_attr(const char *name, int len)
{
        static const int attr_values[] = { 1, 2, 4, 5, 7 };
        static const char * const attr_names[] = {
                "bold", "dim", "ul", "blink", "reverse"
        };
        int i;
        for (i = 0; i < ARRAY_SIZE(attr_names); i++) {
                const char *str = attr_names[i];
                if (!strncasecmp(name, str, len) && !str[len])
                        return attr_values[i];
        }
        return -1;
}

void color_parse(const char *value, const char *var, char *dst)
{
        color_parse_mem(value, strlen(value), var, dst);
}

void color_parse_mem(const char *value, int value_len, const char *var,
                char *dst)
{
        const char *ptr = value;
        int len = value_len;
        unsigned int attr = 0;
        int fg = -2;
        int bg = -2;

        if (!strncasecmp(value, "reset", len)) {
                strcpy(dst, "\033[m");
                return;
        }

        /* [fg [bg]] [attr]... */
        while (len > 0) {
                const char *word = ptr;
                int val, wordlen = 0;

                while (len > 0 && !isspace(word[wordlen])) {
                        wordlen++;
                        len--;
                }

                ptr = word + wordlen;
                while (len > 0 && isspace(*ptr)) {
                        ptr++;
                        len--;
                }

                val = parse_color(word, wordlen);
                if (val >= -1) {
                        if (fg == -2) {
                                fg = val;
                                continue;
                        }
                        if (bg == -2) {
                                bg = val;
                                continue;
                        }
                        goto bad;
                }
                val = parse_attr(word, wordlen);
                if (0 <= val)
                        attr |= (1 << val);
                else
                        goto bad;
        }

        if (attr || fg >= 0 || bg >= 0) {
                int sep = 0;
                int i;

                *dst++ = '\033';
                *dst++ = '[';

                for (i = 0; attr; i++) {
                        unsigned bit = (1 << i);
                        if (!(attr & bit))
                                continue;
                        attr &= ~bit;
                        if (sep++)
                                *dst++ = ';';
                        *dst++ = '0' + i;
                }
                if (fg >= 0) {
                        if (sep++)
                                *dst++ = ';';
                        if (fg < 8) {
                                *dst++ = '3';
                                *dst++ = '0' + fg;
                        } else {
                                dst += sprintf(dst, "38;5;%d", fg);
                        }
                }
                if (bg >= 0) {
                        if (sep++)
                                *dst++ = ';';
                        if (bg < 8) {
                                *dst++ = '4';
                                *dst++ = '0' + bg;
                        } else {
                                dst += sprintf(dst, "48;5;%d", bg);
                        }
                }
                *dst++ = 'm';
        }
        *dst = 0;
        return;
bad:
        die("bad color value '%.*s' for variable '%s'", value_len, value, var);
}

int git_config_colorbool(const char *var, const char *value, int stdout_is_tty)
{
        if (value) {
                if (!strcasecmp(value, "never"))
                        return 0;
                if (!strcasecmp(value, "always"))
                        return 1;
                if (!strcasecmp(value, "auto"))
                        goto auto_color;
        }

        /* Missing or explicit false to turn off colorization */
        if (!git_config_bool(var, value))
                return 0;

        /* any normal truth value defaults to 'auto' */
 auto_color:
        if (stdout_is_tty < 0)
                stdout_is_tty = isatty(1);
        if (stdout_is_tty || (pager_in_use() && pager_use_color)) {
                char *term = getenv("TERM");
                if (term && strcmp(term, "dumb"))
                        return 1;
        }
        return 0;
}

int git_color_default_config(const char *var, const char *value, void *cb)
{
        if (!strcmp(var, "color.ui")) {
                git_use_color_default = git_config_colorbool(var, value, -1);
                return 0;
        }

        return git_default_config(var, value, cb);
}

static int color_vfprintf(FILE *fp, const char *color, const char *fmt,
                va_list args, const char *trail)
{
        int r = 0;

        if (*color)
                r += fprintf(fp, "%s", color);
        r += vfprintf(fp, fmt, args);
        if (*color)
                r += fprintf(fp, "%s", COLOR_RESET);
        if (trail)
                r += fprintf(fp, "%s", trail);
        return r;
}



int color_fprintf(FILE *fp, const char *color, const char *fmt, ...)
{
        va_list args;
        int r;
        va_start(args, fmt);
        r = color_vfprintf(fp, color, fmt, args, NULL);
        va_end(args);
        return r;
}

int color_fprintf_ln(FILE *fp, const char *color, const char *fmt, ...)
{
        va_list args;
        int r;
        va_start(args, fmt);
        r = color_vfprintf(fp, color, fmt, args, "\n");
        va_end(args);
        return r;
}

/*
 * This function splits the buffer by newlines and colors the lines individually.
 *
 * Returns 0 on success.
 */
int color_fwrite_lines(FILE *fp, const char *color,
                size_t count, const char *buf)
{
        if (!*color)
                return fwrite(buf, count, 1, fp) != 1;
        while (count) {
                char *p = memchr(buf, '\n', count);
                if (p != buf && (fputs(color, fp) < 0 ||
                                fwrite(buf, p ? p - buf : count, 1, fp) != 1 ||
                                fputs(COLOR_RESET, fp) < 0))
                        return -1;
                if (!p)
                        return 0;
                if (fputc('\n', fp) < 0)
                        return -1;
                count -= p + 1 - buf;
                buf = p + 1;
        }
        return 0;
}