#include <linux/kernel.h>
#include "cache.h"
#include "config.h"
#include <stdlib.h>
#include <stdio.h>
#include "color.h"
#include <math.h>
#include <unistd.h>

int perf_use_color_default = -1;

int perf_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 (!perf_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()) {
                char *term = getenv("TERM");
                if (term && strcmp(term, "dumb"))
                        return 1;
        }
        return 0;
}

int perf_color_default_config(const char *var, const char *value,
                              void *cb __maybe_unused)
{
        if (!strcmp(var, "color.ui")) {
                perf_use_color_default = perf_config_colorbool(var, value, -1);
                return 0;
        }

        return 0;
}

static int __color_vsnprintf(char *bf, size_t size, const char *color,
                             const char *fmt, va_list args, const char *trail)
{
        int r = 0;

        /*
         * Auto-detect:
         */
        if (perf_use_color_default < 0) {
                if (isatty(1) || pager_in_use())
                        perf_use_color_default = 1;
                else
                        perf_use_color_default = 0;
        }

        if (perf_use_color_default && *color)
                r += scnprintf(bf, size, "%s", color);
        r += vscnprintf(bf + r, size - r, fmt, args);
        if (perf_use_color_default && *color)
                r += scnprintf(bf + r, size - r, "%s", PERF_COLOR_RESET);
        if (trail)
                r += scnprintf(bf + r, size - r, "%s", trail);
        return r;
}

/* Colors are not included in return value */
static int __color_vfprintf(FILE *fp, const char *color, const char *fmt,
                va_list args)
{
        int r = 0;

        /*
         * Auto-detect:
         */
        if (perf_use_color_default < 0) {
                if (isatty(fileno(fp)) || pager_in_use())
                        perf_use_color_default = 1;
                else
                        perf_use_color_default = 0;
        }

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

int color_vsnprintf(char *bf, size_t size, const char *color,
                    const char *fmt, va_list args)
{
        return __color_vsnprintf(bf, size, color, fmt, args, NULL);
}

int color_vfprintf(FILE *fp, const char *color, const char *fmt, va_list args)
{
        return __color_vfprintf(fp, color, fmt, args);
}

int color_snprintf(char *bf, size_t size, const char *color,
                   const char *fmt, ...)
{
        va_list args;
        int r;

        va_start(args, fmt);
        r = color_vsnprintf(bf, size, color, fmt, args);
        va_end(args);
        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);
        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 ? (size_t)(p - buf) : count, 1, fp) != 1 ||
                                fputs(PERF_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;
}

const char *get_percent_color(double percent)
{
        const char *color = PERF_COLOR_NORMAL;

        /*
         * We color high-overhead entries in red, mid-overhead
         * entries in green - and keep the low overhead places
         * normal:
         */
        if (fabs(percent) >= MIN_RED)
                color = PERF_COLOR_RED;
        else {
                if (fabs(percent) > MIN_GREEN)
                        color = PERF_COLOR_GREEN;
        }
        return color;
}

int percent_color_fprintf(FILE *fp, const char *fmt, double percent)
{
        int r;
        const char *color;

        color = get_percent_color(percent);
        r = color_fprintf(fp, color, fmt, percent);

        return r;
}

int value_color_snprintf(char *bf, size_t size, const char *fmt, double value)
{
        const char *color = get_percent_color(value);
        return color_snprintf(bf, size, color, fmt, value);
}

int percent_color_snprintf(char *bf, size_t size, const char *fmt, ...)
{
        va_list args;
        double percent;

        va_start(args, fmt);
        percent = va_arg(args, double);
        va_end(args);
        return value_color_snprintf(bf, size, fmt, percent);
}

int percent_color_len_snprintf(char *bf, size_t size, const char *fmt, ...)
{
        va_list args;
        int len;
        double percent;
        const char *color;

        va_start(args, fmt);
        len = va_arg(args, int);
        percent = va_arg(args, double);
        va_end(args);

        color = get_percent_color(percent);
        return color_snprintf(bf, size, color, fmt, len, percent);
}