import { createWidget } from "discourse/widgets/widget";
import { h } from "virtual-dom";
import { iconNode } from "discourse-common/lib/icon-library";
import RawHtml from "discourse/widgets/raw-html";
import { ajax } from "discourse/lib/ajax";
import { popupAjaxError } from "discourse/lib/ajax-error";
import evenRound from "discourse/plugins/poll/lib/even-round";
import { avatarFor } from "discourse/widgets/post";
import round from "discourse/lib/round";
import { relativeAge } from "discourse/lib/formatter";
import { userPath } from "discourse/lib/url";

function optionHtml(option) {
  return new RawHtml({ html: `<span>${option.html}</span>` });
}

function infoTextHtml(text) {
  return new RawHtml({
    html: `<span class="info-text">${text}</span>`
  });
}

function _fetchVoters(data) {
  return ajax("/polls/voters.json", { data }).catch(error => {
    if (error) {
      popupAjaxError(error);
    } else {
      bootbox.alert(I18n.t("poll.error_while_fetching_voters"));
    }
  });
}

createWidget("discourse-poll-option", {
  tagName: "li",

  buildAttributes(attrs) {
    return { "data-poll-option-id": attrs.option.id };
  },

  html(attrs) {
    const contents = [];
    const { option, vote } = attrs;
    const chosen = vote.includes(option.id);

    if (attrs.isMultiple) {
      contents.push(iconNode(chosen ? "far-check-square" : "far-square"));
    } else {
      contents.push(iconNode(chosen ? "circle" : "far-circle"));
    }

    contents.push(" ");
    contents.push(optionHtml(option));

    return contents;
  },

  click(e) {
    if ($(e.target).closest("a").length === 0) {
      this.sendWidgetAction("toggleOption", this.attrs.option);
    }
  }
});

createWidget("discourse-poll-load-more", {
  tagName: "div.poll-voters-toggle-expand",
  buildKey: attrs => `load-more-${attrs.optionId}`,

  defaultState() {
    return { loading: false };
  },

  html(attrs, state) {
    return state.loading
      ? h("div.spinner.small")
      : h("a", iconNode("chevron-down"));
  },

  click() {
    const { state } = this;

    if (state.loading) return;

    state.loading = true;
    return this.sendWidgetAction("loadMore").finally(
      () => (state.loading = false)
    );
  }
});

createWidget("discourse-poll-voters", {
  tagName: "ul.poll-voters-list",
  buildKey: attrs => `poll-voters-${attrs.optionId}`,

  defaultState() {
    return {
      loaded: "new",
      voters: [],
      page: 1
    };
  },

  fetchVoters() {
    const { attrs, state } = this;

    if (state.loaded === "loading") return;
    state.loaded = "loading";

    return _fetchVoters({
      post_id: attrs.postId,
      poll_name: attrs.pollName,
      option_id: attrs.optionId,
      page: state.page
    }).then(result => {
      state.loaded = "loaded";
      state.page += 1;

      const newVoters =
        attrs.pollType === "number"
          ? result.voters
          : result.voters[attrs.optionId];

      const existingVoters = new Set(state.voters.map(voter => voter.username));

      newVoters.forEach(voter => {
        if (!existingVoters.has(voter.username)) {
          existingVoters.add(voter.username);
          state.voters.push(voter);
        }
      });

      this.scheduleRerender();
    });
  },

  loadMore() {
    return this.fetchVoters();
  },

  html(attrs, state) {
    if (attrs.voters && state.loaded === "new") {
      state.voters = attrs.voters;
    }

    const contents = state.voters.map(user => {
      return h("li", [
        avatarFor("tiny", {
          username: user.username,
          url: this.site.mobileView ? userPath(user.username) : undefined,
          template: user.avatar_template
        }),
        " "
      ]);
    });

    if (state.voters.length < attrs.totalVotes) {
      contents.push(this.attach("discourse-poll-load-more", attrs));
    }

    return h("div.poll-voters", contents);
  }
});

createWidget("discourse-poll-standard-results", {
  tagName: "ul.results",
  buildKey: attrs => `poll-standard-results-${attrs.id}`,

  defaultState() {
    return { loaded: false };
  },

  fetchVoters() {
    const { attrs, state } = this;

    return _fetchVoters({
      post_id: attrs.post.id,
      poll_name: attrs.poll.get("name")
    }).then(result => {
      state.voters = result.voters;
      this.scheduleRerender();
    });
  },

  html(attrs, state) {
    const { poll } = attrs;
    const options = poll.get("options");

    if (options) {
      const voters = poll.get("voters");
      const isPublic = poll.get("public");

      const ordered = _.clone(options).sort((a, b) => {
        if (a.votes < b.votes) {
          return 1;
        } else if (a.votes === b.votes) {
          if (a.html < b.html) {
            return -1;
          } else {
            return 1;
          }
        } else {
          return -1;
        }
      });

      if (isPublic && !state.loaded) {
        state.voters = poll.get("preloaded_voters");
        state.loaded = true;
      }

      const percentages =
        voters === 0
          ? Array(ordered.length).fill(0)
          : ordered.map(o => (100 * o.votes) / voters);

      const rounded = attrs.isMultiple
        ? percentages.map(Math.floor)
        : evenRound(percentages);

      return ordered.map((option, idx) => {
        const contents = [];
        const per = rounded[idx].toString();
        const chosen = (attrs.vote || []).includes(option.id);

        contents.push(
          h(
            "div.option",
            h("p", [h("span.percentage", `${per}%`), optionHtml(option)])
          )
        );

        contents.push(
          h(
            "div.bar-back",
            h("div.bar", { attributes: { style: `width:${per}%` } })
          )
        );

        if (isPublic) {
          contents.push(
            this.attach("discourse-poll-voters", {
              postId: attrs.post.id,
              optionId: option.id,
              pollName: poll.get("name"),
              totalVotes: option.votes,
              voters: (state.voters && state.voters[option.id]) || []
            })
          );
        }

        return h("li", { className: `${chosen ? "chosen" : ""}` }, contents);
      });
    }
  }
});

createWidget("discourse-poll-number-results", {
  buildKey: attrs => `poll-number-results-${attrs.id}`,

  defaultState() {
    return { loaded: false };
  },

  fetchVoters() {
    const { attrs, state } = this;

    return _fetchVoters({
      post_id: attrs.post.id,
      poll_name: attrs.poll.get("name")
    }).then(result => {
      state.voters = result.voters;
      this.scheduleRerender();
    });
  },

  html(attrs, state) {
    const { poll } = attrs;

    const totalScore = poll.get("options").reduce((total, o) => {
      return total + parseInt(o.html, 10) * parseInt(o.votes, 10);
    }, 0);

    const voters = poll.get("voters");
    const average = voters === 0 ? 0 : round(totalScore / voters, -2);
    const averageRating = I18n.t("poll.average_rating", { average });
    const contents = [
      h(
        "div.poll-results-number-rating",
        new RawHtml({ html: `<span>${averageRating}</span>` })
      )
    ];

    if (poll.get("public")) {
      if (!state.loaded) {
        state.voters = poll.get("preloaded_voters");
        state.loaded = true;
      }

      contents.push(
        this.attach("discourse-poll-voters", {
          totalVotes: poll.get("voters"),
          voters: state.voters || [],
          postId: attrs.post.id,
          pollName: poll.get("name"),
          pollType: poll.get("type")
        })
      );
    }

    return contents;
  }
});

createWidget("discourse-poll-container", {
  tagName: "div.poll-container",

  html(attrs) {
    const { poll } = attrs;
    const options = poll.get("options");

    if (attrs.showResults) {
      const type = poll.get("type") === "number" ? "number" : "standard";
      return this.attach(`discourse-poll-${type}-results`, attrs);
    } else if (options) {
      return h(
        "ul",
        options.map(option => {
          return this.attach("discourse-poll-option", {
            option,
            isMultiple: attrs.isMultiple,
            vote: attrs.vote
          });
        })
      );
    }
  }
});

createWidget("discourse-poll-info", {
  tagName: "div.poll-info",

  multipleHelpText(min, max, options) {
    if (max > 0) {
      if (min === max) {
        if (min > 1) {
          return I18n.t("poll.multiple.help.x_options", { count: min });
        }
      } else if (min > 1) {
        if (max < options) {
          return I18n.t("poll.multiple.help.between_min_and_max_options", {
            min,
            max
          });
        } else {
          return I18n.t("poll.multiple.help.at_least_min_options", {
            count: min
          });
        }
      } else if (max <= options) {
        return I18n.t("poll.multiple.help.up_to_max_options", { count: max });
      }
    }
  },

  html(attrs) {
    const { poll } = attrs;
    const count = poll.get("voters");
    const contents = [
      h("p", [
        h("span.info-number", count.toString()),
        h("span.info-label", I18n.t("poll.voters", { count }))
      ])
    ];

    if (attrs.isMultiple) {
      if (attrs.showResults || attrs.isClosed) {
        const totalVotes = poll.get("options").reduce((total, o) => {
          return total + parseInt(o.votes, 10);
        }, 0);

        contents.push(
          h("p", [
            h("span.info-number", totalVotes.toString()),
            h(
              "span.info-label",
              I18n.t("poll.total_votes", { count: totalVotes })
            )
          ])
        );
      } else {
        const help = this.multipleHelpText(
          attrs.min,
          attrs.max,
          poll.get("options.length")
        );
        if (help) {
          contents.push(infoTextHtml(help));
        }
      }
    }

    if (!attrs.isClosed && !attrs.showResults && poll.get("public")) {
      contents.push(infoTextHtml(I18n.t("poll.public.title")));
    }

    return contents;
  }
});

createWidget("discourse-poll-buttons", {
  tagName: "div.poll-buttons",

  html(attrs) {
    const contents = [];
    const { poll, post } = attrs;
    const topicArchived = post.get("topic.archived");
    const closed = attrs.isClosed;
    const hideResultsDisabled = closed || topicArchived;

    if (attrs.isMultiple && !hideResultsDisabled) {
      const castVotesDisabled = !attrs.canCastVotes;
      contents.push(
        this.attach("button", {
          className: `btn cast-votes ${
            castVotesDisabled ? "btn-default" : "btn-primary"
          }`,
          label: "poll.cast-votes.label",
          title: "poll.cast-votes.title",
          disabled: castVotesDisabled,
          action: "castVotes"
        })
      );
      contents.push(" ");
    }

    if (attrs.showResults || hideResultsDisabled) {
      contents.push(
        this.attach("button", {
          className: "btn btn-default toggle-results",
          label: "poll.hide-results.label",
          title: "poll.hide-results.title",
          icon: "far-eye-slash",
          disabled: hideResultsDisabled,
          action: "toggleResults"
        })
      );
    } else {
      if (poll.get("results") === "on_vote" && !attrs.hasVoted) {
        contents.push(infoTextHtml(I18n.t("poll.results.vote.title")));
      } else if (poll.get("results") === "on_close" && !closed) {
        contents.push(infoTextHtml(I18n.t("poll.results.closed.title")));
      } else {
        contents.push(
          this.attach("button", {
            className: "btn btn-default toggle-results",
            label: "poll.show-results.label",
            title: "poll.show-results.title",
            icon: "far-eye",
            disabled: poll.get("voters") === 0,
            action: "toggleResults"
          })
        );
      }
    }

    if (poll.get("close")) {
      const closeDate = moment.utc(poll.get("close"));
      if (closeDate.isValid()) {
        const title = closeDate.format("LLL");
        let label;

        if (attrs.isAutomaticallyClosed) {
          const age = relativeAge(closeDate.toDate(), { addAgo: true });
          label = I18n.t("poll.automatic_close.age", { age });
        } else {
          const timeLeft = moment().to(closeDate.local(), true);
          label = I18n.t("poll.automatic_close.closes_in", { timeLeft });
        }

        contents.push(
          new RawHtml({
            html: `<span class="info-text" title="${title}">${label}</span>`
          })
        );
      }
    }

    if (
      this.currentUser &&
      (this.currentUser.get("id") === post.get("user_id") ||
        this.currentUser.get("staff")) &&
      !topicArchived
    ) {
      if (closed) {
        if (!attrs.isAutomaticallyClosed) {
          contents.push(
            this.attach("button", {
              className: "btn btn-default toggle-status",
              label: "poll.open.label",
              title: "poll.open.title",
              icon: "unlock-alt",
              action: "toggleStatus"
            })
          );
        }
      } else {
        contents.push(
          this.attach("button", {
            className: "btn toggle-status btn-danger",
            label: "poll.close.label",
            title: "poll.close.title",
            icon: "lock",
            action: "toggleStatus"
          })
        );
      }
    }

    return contents;
  }
});

export default createWidget("discourse-poll", {
  tagName: "div.poll",
  buildKey: attrs => `poll-${attrs.id}`,

  buildAttributes(attrs) {
    return {
      "data-poll-name": attrs.poll.get("name"),
      "data-poll-type": attrs.poll.get("type")
    };
  },

  defaultState(attrs) {
    const { post, poll } = attrs;

    const showResults =
      post.get("topic.archived") ||
      this.isClosed() ||
      (poll.get("results") !== "on_close" && this.hasVoted());

    return { loading: false, showResults };
  },

  html(attrs, state) {
    const showResults =
      state.showResults || attrs.post.get("topic.archived") || this.isClosed();

    const newAttrs = jQuery.extend({}, attrs, {
      canCastVotes: this.canCastVotes(),
      hasVoted: this.hasVoted(),
      isAutomaticallyClosed: this.isAutomaticallyClosed(),
      isClosed: this.isClosed(),
      isMultiple: this.isMultiple(),
      max: this.max(),
      min: this.min(),
      showResults
    });

    return h("div", [
      this.attach("discourse-poll-container", newAttrs),
      this.attach("discourse-poll-info", newAttrs),
      this.attach("discourse-poll-buttons", newAttrs)
    ]);
  },

  min() {
    let min = parseInt(this.attrs.poll.get("min"), 10);
    if (isNaN(min) || min < 0) {
      min = 0;
    }
    return min;
  },

  max() {
    let max = parseInt(this.attrs.poll.get("max"), 10);
    const numOptions = this.attrs.poll.get("options.length");
    if (isNaN(max) || max > numOptions) {
      max = numOptions;
    }
    return max;
  },

  isAutomaticallyClosed() {
    const { poll } = this.attrs;
    return poll.get("close") && moment.utc(poll.get("close")) <= moment();
  },

  isClosed() {
    const { poll } = this.attrs;
    return poll.get("status") === "closed" || this.isAutomaticallyClosed();
  },

  isMultiple() {
    const { poll } = this.attrs;
    return poll.get("type") === "multiple";
  },

  hasVoted() {
    const { vote } = this.attrs;
    return vote && vote.length > 0;
  },

  canCastVotes() {
    const { state, attrs } = this;

    if (this.isClosed() || state.showResults || state.loading) {
      return false;
    }

    const selectedOptionCount = attrs.vote.length;

    if (this.isMultiple()) {
      return (
        selectedOptionCount >= this.min() && selectedOptionCount <= this.max()
      );
    }

    return selectedOptionCount > 0;
  },

  toggleStatus() {
    const { state, attrs } = this;
    const { post, poll } = attrs;

    if (this.isAutomaticallyClosed()) {
      return;
    }

    bootbox.confirm(
      I18n.t(this.isClosed() ? "poll.open.confirm" : "poll.close.confirm"),
      I18n.t("no_value"),
      I18n.t("yes_value"),
      confirmed => {
        if (confirmed) {
          state.loading = true;
          const status = this.isClosed() ? "open" : "closed";

          ajax("/polls/toggle_status", {
            type: "PUT",
            data: {
              post_id: post.get("id"),
              poll_name: poll.get("name"),
              status
            }
          })
            .then(() => {
              poll.set("status", status);
              if (poll.get("results") === "on_close") {
                state.showResults = status === "closed";
              }
              this.scheduleRerender();
            })
            .catch(error => {
              if (error) {
                popupAjaxError(error);
              } else {
                bootbox.alert(I18n.t("poll.error_while_toggling_status"));
              }
            })
            .finally(() => {
              state.loading = false;
            });
        }
      }
    );
  },

  toggleResults() {
    this.state.showResults = !this.state.showResults;
  },

  showLogin() {
    this.register.lookup("route:application").send("showLogin");
  },

  toggleOption(option) {
    const { attrs } = this;

    if (this.isClosed()) return;
    if (!this.currentUser) return this.showLogin();

    const { vote } = attrs;
    const chosenIdx = vote.indexOf(option.id);

    if (!this.isMultiple()) {
      vote.length = 0;
    }

    if (chosenIdx !== -1) {
      vote.splice(chosenIdx, 1);
    } else {
      vote.push(option.id);
    }

    if (!this.isMultiple()) {
      return this.castVotes();
    }
  },

  castVotes() {
    if (!this.canCastVotes()) return;
    if (!this.currentUser) return this.showLogin();

    const { attrs, state } = this;

    state.loading = true;

    return ajax("/polls/vote", {
      type: "PUT",
      data: {
        post_id: attrs.post.id,
        poll_name: attrs.poll.get("name"),
        options: attrs.vote
      }
    })
      .then(({ poll }) => {
        attrs.poll.setProperties(poll);
        if (attrs.poll.get("results") !== "on_close") {
          state.showResults = true;
        }
      })
      .catch(error => {
        if (error) {
          popupAjaxError(error);
        } else {
          bootbox.alert(I18n.t("poll.error_while_casting_votes"));
        }
      })
      .finally(() => {
        state.loading = false;
      });
  }
});