#include "builtin.h"
#include "cache.h"
#include "commit.h"
#include "diff.h"
#include "string-list.h"
#include "revision.h"
#include "utf8.h"
#include "mailmap.h"
#include "shortlog.h"
#include "parse-options.h"

static char const * const shortlog_usage[] = {
        "git shortlog [-n] [-s] [-e] [-w] [rev-opts] [--] [<commit-id>... ]",
        "",
        "[rev-opts] are documented in git-rev-list(1)",
        NULL
};

static int compare_by_number(const void *a1, const void *a2)
{
        const struct string_list_item *i1 = a1, *i2 = a2;
        const struct string_list *l1 = i1->util, *l2 = i2->util;

        if (l1->nr < l2->nr)
                return 1;
        else if (l1->nr == l2->nr)
                return 0;
        else
                return -1;
}

const char *format_subject(struct strbuf *sb, const char *msg,
                           const char *line_separator);

static void insert_one_record(struct shortlog *log,
                              const char *author,
                              const char *oneline)
{
        const char *dot3 = log->common_repo_prefix;
        char *buffer, *p;
        struct string_list_item *item;
        char namebuf[1024];
        char emailbuf[1024];
        size_t len;
        const char *eol;
        const char *boemail, *eoemail;
        struct strbuf subject = STRBUF_INIT;

        boemail = strchr(author, '<');
        if (!boemail)
                return;
        eoemail = strchr(boemail, '>');
        if (!eoemail)
                return;

        /* copy author name to namebuf, to support matching on both name and email */
        memcpy(namebuf, author, boemail - author);
        len = boemail - author;
        while (len > 0 && isspace(namebuf[len-1]))
                len--;
        namebuf[len] = 0;

        /* copy email name to emailbuf, to allow email replacement as well */
        memcpy(emailbuf, boemail+1, eoemail - boemail);
        emailbuf[eoemail - boemail - 1] = 0;

        if (!map_user(&log->mailmap, emailbuf, sizeof(emailbuf), namebuf, sizeof(namebuf))) {
                while (author < boemail && isspace(*author))
                        author++;
                for (len = 0;
                     len < sizeof(namebuf) - 1 && author + len < boemail;
                     len++)
                        namebuf[len] = author[len];
                while (0 < len && isspace(namebuf[len-1]))
                        len--;
                namebuf[len] = '\0';
        }
        else
                len = strlen(namebuf);

        if (log->email) {
                size_t room = sizeof(namebuf) - len - 1;
                int maillen = strlen(emailbuf);
                snprintf(namebuf + len, room, " <%.*s>", maillen, emailbuf);
        }

        item = string_list_insert(&log->list, namebuf);
        if (item->util == NULL)
                item->util = xcalloc(1, sizeof(struct string_list));

        /* Skip any leading whitespace, including any blank lines. */
        while (*oneline && isspace(*oneline))
                oneline++;
        eol = strchr(oneline, '\n');
        if (!eol)
                eol = oneline + strlen(oneline);
        if (!prefixcmp(oneline, "[PATCH")) {
                char *eob = strchr(oneline, ']');
                if (eob && (!eol || eob < eol))
                        oneline = eob + 1;
        }
        while (*oneline && isspace(*oneline) && *oneline != '\n')
                oneline++;
        format_subject(&subject, oneline, " ");
        buffer = strbuf_detach(&subject, NULL);

        if (dot3) {
                int dot3len = strlen(dot3);
                if (dot3len > 5) {
                        while ((p = strstr(buffer, dot3)) != NULL) {
                                int taillen = strlen(p) - dot3len;
                                memcpy(p, "/.../", 5);
                                memmove(p + 5, p + dot3len, taillen + 1);
                        }
                }
        }

        string_list_append(item->util, buffer);
}

static void read_from_stdin(struct shortlog *log)
{
        char author[1024], oneline[1024];

        while (fgets(author, sizeof(author), stdin) != NULL) {
                if (!(author[0] == 'A' || author[0] == 'a') ||
                    prefixcmp(author + 1, "uthor: "))
                        continue;
                while (fgets(oneline, sizeof(oneline), stdin) &&
                       oneline[0] != '\n')
                        ; /* discard headers */
                while (fgets(oneline, sizeof(oneline), stdin) &&
                       oneline[0] == '\n')
                        ; /* discard blanks */
                insert_one_record(log, author + 8, oneline);
        }
}

void shortlog_add_commit(struct shortlog *log, struct commit *commit)
{
        const char *author = NULL, *buffer;
        struct strbuf buf = STRBUF_INIT;
        struct strbuf ufbuf = STRBUF_INIT;
        struct pretty_print_context ctx = {0};

        pretty_print_commit(CMIT_FMT_RAW, commit, &buf, &ctx);
        buffer = buf.buf;
        while (*buffer && *buffer != '\n') {
                const char *eol = strchr(buffer, '\n');

                if (eol == NULL)
                        eol = buffer + strlen(buffer);
                else
                        eol++;

                if (!prefixcmp(buffer, "author "))
                        author = buffer + 7;
                buffer = eol;
        }
        if (!author)
                die("Missing author: %s",
                    sha1_to_hex(commit->object.sha1));
        if (log->user_format) {
                struct pretty_print_context ctx = {0};
                ctx.abbrev = log->abbrev;
                ctx.subject = "";
                ctx.after_subject = "";
                ctx.date_mode = DATE_NORMAL;
                pretty_print_commit(CMIT_FMT_USERFORMAT, commit, &ufbuf, &ctx);
                buffer = ufbuf.buf;
        } else if (*buffer) {
                buffer++;
        }
        insert_one_record(log, author, !*buffer ? "<none>" : buffer);
        strbuf_release(&ufbuf);
        strbuf_release(&buf);
}

static void get_from_rev(struct rev_info *rev, struct shortlog *log)
{
        struct commit *commit;

        if (prepare_revision_walk(rev))
                die("revision walk setup failed");
        while ((commit = get_revision(rev)) != NULL)
                shortlog_add_commit(log, commit);
}

static int parse_uint(char const **arg, int comma, int defval)
{
        unsigned long ul;
        int ret;
        char *endp;

        ul = strtoul(*arg, &endp, 10);
        if (*endp && *endp != comma)
                return -1;
        if (ul > INT_MAX)
                return -1;
        ret = *arg == endp ? defval : (int)ul;
        *arg = *endp ? endp + 1 : endp;
        return ret;
}

static const char wrap_arg_usage[] = "-w[<width>[,<indent1>[,<indent2>]]]";
#define DEFAULT_WRAPLEN 76
#define DEFAULT_INDENT1 6
#define DEFAULT_INDENT2 9

static int parse_wrap_args(const struct option *opt, const char *arg, int unset)
{
        struct shortlog *log = opt->value;

        log->wrap_lines = !unset;
        if (unset)
                return 0;
        if (!arg) {
                log->wrap = DEFAULT_WRAPLEN;
                log->in1 = DEFAULT_INDENT1;
                log->in2 = DEFAULT_INDENT2;
                return 0;
        }

        log->wrap = parse_uint(&arg, ',', DEFAULT_WRAPLEN);
        log->in1 = parse_uint(&arg, ',', DEFAULT_INDENT1);
        log->in2 = parse_uint(&arg, '\0', DEFAULT_INDENT2);
        if (log->wrap < 0 || log->in1 < 0 || log->in2 < 0)
                return error(wrap_arg_usage);
        if (log->wrap &&
            ((log->in1 && log->wrap <= log->in1) ||
             (log->in2 && log->wrap <= log->in2)))
                return error(wrap_arg_usage);
        return 0;
}

void shortlog_init(struct shortlog *log)
{
        memset(log, 0, sizeof(*log));

        read_mailmap(&log->mailmap, &log->common_repo_prefix);

        log->list.strdup_strings = 1;
        log->wrap = DEFAULT_WRAPLEN;
        log->in1 = DEFAULT_INDENT1;
        log->in2 = DEFAULT_INDENT2;
}

int cmd_shortlog(int argc, const char **argv, const char *prefix)
{
        static struct shortlog log;
        static struct rev_info rev;
        int nongit = !startup_info->have_repository;

        static const struct option options[] = {
                OPT_BOOLEAN('n', "numbered", &log.sort_by_number,
                            "sort output according to the number of commits per author"),
                OPT_BOOLEAN('s', "summary", &log.summary,
                            "Suppress commit descriptions, only provides commit count"),
                OPT_BOOLEAN('e', "email", &log.email,
                            "Show the email address of each author"),
                { OPTION_CALLBACK, 'w', NULL, &log, "w[,i1[,i2]]",
                        "Linewrap output", PARSE_OPT_OPTARG, &parse_wrap_args },
                OPT_END(),
        };

        struct parse_opt_ctx_t ctx;

        git_config(git_default_config, NULL);
        shortlog_init(&log);
        init_revisions(&rev, prefix);
        parse_options_start(&ctx, argc, argv, prefix, PARSE_OPT_KEEP_DASHDASH |
                            PARSE_OPT_KEEP_ARGV0);

        for (;;) {
                switch (parse_options_step(&ctx, options, shortlog_usage)) {
                case PARSE_OPT_HELP:
                        exit(129);
                case PARSE_OPT_DONE:
                        goto parse_done;
                }
                parse_revision_opt(&rev, &ctx, options, shortlog_usage);
        }
parse_done:
        argc = parse_options_end(&ctx);

        if (setup_revisions(argc, argv, &rev, NULL) != 1) {
                error("unrecognized argument: %s", argv[1]);
                usage_with_options(shortlog_usage, options);
        }

        log.user_format = rev.commit_format == CMIT_FMT_USERFORMAT;
        log.abbrev = rev.abbrev;

        /* assume HEAD if from a tty */
        if (!nongit && !rev.pending.nr && isatty(0))
                add_head_to_pending(&rev);
        if (rev.pending.nr == 0) {
                if (isatty(0))
                        fprintf(stderr, "(reading log message from standard input)\n");
                read_from_stdin(&log);
        }
        else
                get_from_rev(&rev, &log);

        shortlog_output(&log);
        return 0;
}

static void add_wrapped_shortlog_msg(struct strbuf *sb, const char *s,
                                     const struct shortlog *log)
{
        int col = strbuf_add_wrapped_text(sb, s, log->in1, log->in2, log->wrap);
        if (col != log->wrap)
                strbuf_addch(sb, '\n');
}

void shortlog_output(struct shortlog *log)
{
        int i, j;
        struct strbuf sb = STRBUF_INIT;

        if (log->sort_by_number)
                qsort(log->list.items, log->list.nr, sizeof(struct string_list_item),
                        compare_by_number);
        for (i = 0; i < log->list.nr; i++) {
                struct string_list *onelines = log->list.items[i].util;

                if (log->summary) {
                        printf("%6d\t%s\n", onelines->nr, log->list.items[i].string);
                } else {
                        printf("%s (%d):\n", log->list.items[i].string, onelines->nr);
                        for (j = onelines->nr - 1; j >= 0; j--) {
                                const char *msg = onelines->items[j].string;

                                if (log->wrap_lines) {
                                        strbuf_reset(&sb);
                                        add_wrapped_shortlog_msg(&sb, msg, log);
                                        fwrite(sb.buf, sb.len, 1, stdout);
                                }
                                else
                                        printf("      %s\n", msg);
                        }
                        putchar('\n');
                }

                onelines->strdup_strings = 1;
                string_list_clear(onelines, 0);
                free(onelines);
                log->list.items[i].util = NULL;
        }

        strbuf_release(&sb);
        log->list.strdup_strings = 1;
        string_list_clear(&log->list, 1);
        clear_mailmap(&log->mailmap);
}